Diarrhoea

Last updated 31 May 2026 · Gastroenterology

📋 Key Information Summary

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Acute diarrhoea lasts <14 days; chronic diarrhoea persists ≥4 weeks and demands a structured diagnostic workup including FBC, CRP, faecal calprotectin, coeliac serology, and stool microscopy/culture.
Bacterial food poisoning typically presents within 72 hours of ingestion with prominent vomiting and/or bloody stool; viral gastroenteritis (norovirus, rotavirus) is the most common cause of acute diarrhoea in Australia, usually self-limiting within 3–5 days.
Oral rehydration solution (ORS) is first-line for mild–moderate dehydration in all age groups; IV normal saline or Hartmann's solution is reserved for severe dehydration or inability to tolerate oral intake.
Campylobacter spp. is the most frequently notified enteric pathogen in Australia; antibiotic treatment (azithromycin 500 mg PO daily for 3 days) is recommended for severe or systemic infection, not routine cases.
Inflammatory bowel disease (IBD) — Crohn's disease and ulcerative colitis — accounts for a significant burden of chronic diarrhoea in young Australians; faecal calprotectin >250 μg/g strongly suggests inflammatory aetiology and warrants urgent gastroenterology referral.
Clostridioides difficile infection (CDI) should be suspected in any patient with diarrhoea and recent antibiotic exposure (within 12 weeks); first-line treatment is oral vancomycin 125 mg QDS for 10 days (PBS Authority Required).
Chronic diarrhoea requires exclusion of coeliac disease (anti-tTG IgA), microscopic colitis (colonoscopic biopsies), bile acid malabsorption (SeHCAT or therapeutic trial of cholestyramine), and pancreatic insufficiency (faecal elastase-1).
Antimotility agents (loperamide) are safe in non-invasive, non-bloody diarrhoea but contraindicated in suspected invasive bacterial infection, C. difficile, and children <2 years.
Aboriginal and Torres Strait Islander peoples experience 3–5 times the rate of gastroenteritis hospitalisations compared with non-Indigenous Australians; access to clean water, sanitation, and timely primary care are critical determinants.
Red-flag features requiring urgent assessment: signs of severe dehydration, bloody diarrhoea, fever >38.5°C with systemic toxicity, immunocompromised state, age >65 years with comorbidities, and diarrhoea lasting >7 days.
IBD flare management involves corticosteroid induction (prednisolone 40 mg PO daily, weaned over 8 weeks), 5-ASA agents for maintenance, and biologic therapy (infliximab, vedolizumab) for moderate–severe disease, guided by a gastroenterologist.
Notification requirements under state/territory public health legislation: Salmonella, Shigella, Campylobacter, C. difficile (in some jurisdictions), STEC, and Giardia are notifiable diseases in Australia.

Introduction & Australian Epidemiology

Diarrhoea — defined as the passage of three or more loose or watery stools per day, or an increase in stool weight above 200 g/day — is one of the most common presentations in Australian general practice and emergency departments. It is broadly classified as acute (<14 days), persistent (14–28 days), or chronic (≥4 weeks), with aetiologies ranging from self-limiting viral infections to life-threatening inflammatory and infectious conditions.

In Australia, gastroenteritis accounts for approximately 17.2 million cases annually, resulting in an estimated 15,000 hospital admissions per year. The annual economic burden exceeds 0 million in direct healthcare costs. Norovirus is the leading cause of acute gastroenteritis outbreaks in the community and healthcare facilities, while Campylobacter remains the most commonly notified enteric pathogen nationally (~33,000 notifications per year), followed by Salmonella species (~16,000 notifications/year).

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Notification burden: Australia has one of the highest rates of campylobacteriosis in the developed world, with peak incidence in children under 5 years and young adults aged 20–29 years. Southeast Asian travel-related infections account for a significant proportion of enteric fever and shigellosis cases.

Chronic diarrhoea affects approximately 5% of the Australian adult population at any given time. Inflammatory bowel disease (IBD) — encompassing Crohn's disease and ulcerative colitis — has an increasing incidence in Australia, with current prevalence estimated at 1 in 250 individuals (approximately 100,000 people). Australia has among the highest incidence rates of IBD globally, particularly in the paediatric population.

Clostridioides difficile infection (CDI) remains a significant healthcare-associated threat, with approximately 4,000–5,000 cases reported annually in Australian hospitals. The hypervirulent ribotype 027 has been increasingly identified, and recurrent CDI (occurring in 20–30% of cases) poses a substantial management challenge. Faecal microbiota transplantation (FMT) is now established as standard-of-care for multiply recurrent CDI, available through specialist centres across Australia.

This guideline provides a structured approach to the diagnosis and management of diarrhoea in Australian primary and secondary care, encompassing acute infectious causes, inflammatory bowel disease, C. difficile infection, and chronic diarrhoeal syndromes.

Diarrhoea Diagnostic Model

A systematic approach to the patient presenting with diarrhoea is essential to differentiate benign self-limiting illness from conditions requiring urgent intervention. The diagnostic model below integrates history, examination findings, and targeted investigations to guide clinical decision-making.

Step 1: Characterise the Diarrhoea

Feature	Questions to Ask	Diagnostic Significance
Duration	<14 days vs ≥4 weeks	Acute: infectious most likely. Chronic: IBD, coeliac, functional (IBS-D), microscopic colitis
Stool consistency & volume	Watery vs mucoid vs greasy vs bloody	Watery: secretory/osmotic. Bloody: invasive organism or IBD. Greasy: malabsorption (coeliac, pancreatic)
Frequency	Number of stools per 24 hours	>6 stools/day with blood suggests severe colitis or dysentery
Nocturnal symptoms	Does diarrhoea wake the patient?	Nocturnal diarrhoea suggests organic disease (IBD, microscopic colitis, diabetic autonomic neuropathy), not IBS
Systemic symptoms	Fever, weight loss, arthralgia, rash	Fever + bloody stool: invasive bacteria or IBD flare. Weight loss: IBD, coeliac, malignancy
Dietary / travel / contacts	Recent food history, overseas travel, sick contacts	Travel: consider Salmonella, Shigella, Campylobacter, parasites. Raw shellfish: Vibrio, norovirus
Medications	Recent antibiotics, NSAIDs, metformin, PPIs, SSRIs	Antibiotics: C. difficile. Metformin: common cause of osmotic diarrhoea. PPIs: C. difficile risk factor

Step 2: Clinical Assessment & Severity Grading

Mild

Mild Dehydration

Thirst, slightly dry mucous membranes, normal vital signs, urine output mildly reduced (>1 mL/kg/hr). No blood in stool. Alert and oriented.

Setting: Community / GP management

Moderate

Moderate Dehydration

Tachycardia (HR >100 bpm), sunken eyes, skin turgor reduced (tenting >2 sec), reduced urine output (0.5–1 mL/kg/hr). May have blood or mucus in stool. Postural hypotension present.

Setting: ED assessment / short-stay

Severe

Severe Dehydration / Toxicity

Hypotension (SBP <90 mmHg), tachycardia (HR >120 bpm), oliguria (<0.5 mL/kg/hr), altered consciousness, significant bloody diarrhoea, fever >39°C, signs of sepsis.

Setting: Emergency resuscitation / inpatient admission

Step 3: Initial Investigations (Bedside & Laboratory)

Essential Stool microscopy, culture & sensitivity (MC&S) All patients with bloody diarrhoea, fever >38°C, duration >7 days, immunocompromised, or recent hospitalisation. MBS Item 69313.

Essential Faecal multiplex PCR (GI pathogen panel) Rapid syndromic testing for bacteria, viruses, and parasites. Available at major Australian pathology services (e.g., Sullivan Nicolaides, Pathology Queensland). Replaces traditional stool O&P in most settings.

Essential Full blood count (FBC), CRP, UEC, LFTs Assess for leucocytosis, renal impairment, electrolyte derangement, raised inflammatory markers. MBS Item 65070.

Available Faecal calprotectin Sensitivity 95% for intestinal inflammation. >50 μg/g suggestive; >250 μg/g highly suggestive of IBD. Distinguish inflammatory from functional diarrhoea. MBS Item 66924.

Available C. difficile toxin (GDH + toxin A/B EIA ± PCR) Two-step algorithm: GDH screen → toxin EIA confirmation. Nucleic acid amplification test (NAAT/PCR) if clinical suspicion remains high. MBS Item 69437.

Available Coeliac serology (anti-tTG IgA + total IgA) Screen all patients with chronic diarrhoea, iron deficiency, weight loss, or family history. Patient must be on gluten-containing diet. MBS Item 66812.

Specialist Colonoscopy with ileoscopy and random biopsies Indicated for chronic diarrhoea with positive faecal calprotectin, suspected IBD, microscopic colitis, or colorectal malignancy. MBS Item 32222.

Specialist Faecal elastase-1 Screen for pancreatic exocrine insufficiency. <200 μg/g indicates moderate insufficiency; <100 μg/g indicates severe insufficiency. Available through reference laboratories.

Step 4: Diagnostic Decision Pathway

Duration <14 days?

Acute diarrhoea → assess hydration, stool character, systemic signs. Most are viral and self-limiting. Test for C. difficile if antibiotic exposure. Stool MC&S if bloody, febrile, or >7 days.

Duration 14–28 days?

Persistent diarrhoea → faecal calprotectin, coeliac serology, stool PCR, C. difficile toxin. Consider Giardia, post-infectious IBS, or developing IBD. Refer for colonoscopy if inflammatory markers elevated.

Duration ≥4 weeks?

Chronic diarrhoea → comprehensive workup. Check FBC, CRP, TFT, coeliac serology, faecal calprotectin, faecal elastase, 24-hour stool fat if steatorrhoea. Colonoscopy with biopsies if alarm features or positive screen.

All screens negative?

Consider bile acid malabsorption (SeHCAT scan or therapeutic trial of cholestyramine), microscopic colitis (requires colonoscopic biopsies), medication-induced diarrhoea, or functional diarrhoea (IBS-D, Rome IV criteria).

Bacterial Food Poisoning vs Viral Gastroenteritis

Distinguishing between bacterial food poisoning and viral gastroenteritis is a cornerstone of diarrhoea management. While most cases are self-limiting and require only supportive care, correct aetiological classification guides the need for antimicrobial therapy, infection control measures, and public health notification.

Feature	Bacterial Food Poisoning	Viral Gastroenteritis
Incubation	1–72 hours (toxin-mediated: 1–6 hrs; invasive: 12–72 hrs)	12–48 hours (norovirus: 12–48 hrs; rotavirus: 1–3 days)
Onset	Often acute, may follow a recognised meal/event	Subacute; household/community spread common
Vomiting	Prominent in toxin-mediated (S. aureus, B. cereus); less prominent in invasive	Often prominent, especially norovirus. Projectile in rotavirus paediatric cases
Stool character	Invasive: bloody/mucoid. Toxin: watery. C. perfringens: watery, profuse	Watery, non-bloody. Green or yellow in rotavirus
Fever	Common in invasive infection (38.5–40°C). Absent in toxin-mediated	Low-grade (37.5–38.5°C) or absent
Duration	Toxin: 12–24 hrs. Invasive: 3–7 days. Campylobacter: up to 10 days	Typically 3–5 days; norovirus 1–3 days
Key organisms	Campylobacter, Salmonella, Shigella, STEC, S. aureus, B. cereus, C. perfringens	Norovirus, rotavirus, adenovirus 40/41, astrovirus
Treatment	Supportive ± antibiotics for severe/systemic illness. See drug cards below	Supportive care only. ORS + early refeeding. Antiemetics (ondansetron) if significant vomiting

Common Bacterial Causes in Australia

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Campylobacter jejuni

Most common notifiable enteric pathogen in Australia

Source Undercooked poultry, unpasteurised milk, contaminated water

Incubation 2–5 days

Presentation Prodromal malaise → bloody/mucoid diarrhoea, severe crampy abdominal pain, fever. May mimic appendicitis (mesenteric adenitis)

Antibiotic (if severe) Azithromycin 500 mg PO OD for 3 days (eTG first-line)

PBS status ✔ PBS General Benefit

Complication Guillain–Barré syndrome (1 in 1,000), reactive arthritis, post-infectious IBS

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Salmonella species

Non-typhoidal: S. Typhimurium (most common in AU)

Source Eggs, poultry, reptile/amphibian contact, sprouts

Incubation 6–72 hours

Presentation Watery → bloody diarrhoea, fever, nausea, vomiting. Duration 4–7 days

Antibiotic (if severe/invasive) Ciprofloxacin 500 mg PO BD or azithromycin 500 mg PO OD for 3–5 days

PBS status ✔ PBS General Benefit (ciprofloxacin); ✔ PBS General Benefit (azithromycin)

Note Antibiotics NOT recommended for uncomplicated non-typhoidal salmonellosis — may prolong carriage

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Shigella species

Shigella sonnei most common in Australia

Source Person-to-person faecal–oral, contaminated food/water. Increasing in MSM populations

Incubation 1–3 days

Presentation Acute bloody diarrhoea (dysentery), high fever, tenesmus, abdominal cramps. Stools may contain mucus and blood

Antibiotic Azithromycin 500 mg PO OD for 3 days (first-line). Ciprofloxacin 500 mg PO BD for 3 days if susceptibility confirmed

PBS status ✔ PBS General Benefit

Notification Notifiable in all Australian states/territories

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Shiga toxin-producing E. coli (STEC)

Includes O157:H7. Haemolytic uraemic syndrome (HUS) risk

Source Undercooked beef, raw milk, contaminated produce, petting zoos

Presentation Watery diarrhoea progressing to bloody diarrhoea (haemorrhagic colitis). 5–10% develop HUS (paediatric/elderly)

Treatment Supportive care ONLY. No antibiotics — may increase HUS risk. No antimotility agents

Monitoring FBC (schistocytes), UEC (creatinine), LDH, haptoglobin — screen for HUS

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STEC / HUS Warning: Do NOT prescribe antibiotics or antimotility agents (loperamide) for suspected STEC infection. Antibiotics may trigger Shiga toxin release and precipitate haemolytic uraemic syndrome (HUS). Any child with bloody diarrhoea, pallor, or reduced urine output should be assessed urgently for HUS.

Viral Gastroenteritis Management

Viral gastroenteritis is the most common cause of acute diarrhoea in all age groups in Australia. Norovirus is responsible for >90% of non-bacterial gastroenteritis outbreaks and the majority of gastroenteritis-related emergency presentations during winter months. Rotavirus, though now largely prevented by vaccination (Rotarix® or RotaTeq® on the National Immunisation Program for infants), still causes significant disease in unvaccinated or incompletely vaccinated children.

Supportive Care (All Viral GE)

Oral rehydration solution (WHO-ORS or Gastrolyte®) — small frequent sips
Early refeeding with age-appropriate diet when tolerated (avoid prolonged fasting)
Ondansetron 4 mg wafer PO (adults) / weight-based for children to reduce vomiting and facilitate ORS intake
Loperamide 4 mg PO stat then 2 mg after each loose stool (max 16 mg/day) for adults with non-bloody, non-febrile diarrhoea — NOT for children <12 years
No antibiotics indicated

When to Escalate

Unable to tolerate oral fluids for >4–6 hours
Signs of moderate–severe dehydration (sunken eyes, poor turgor, tachycardia)
Immunocompromised patient (HIV, transplant, chemotherapy)
Age >65 with multiple comorbidities
Bloody diarrhoea or high fever (>38.5°C)
Duration >7 days without improvement

Inflammatory Bowel Disease (Crohn's Disease & Ulcerative Colitis)

Inflammatory bowel disease (IBD) is a chronic, relapsing inflammatory condition of the gastrointestinal tract with an increasing incidence in Australia. Approximately 100,000 Australians live with IBD, with peak onset between 15 and 35 years of age. Crohn's disease and ulcerative colitis have distinct pathological features, distributions, and management approaches, but both commonly present with chronic or recurrent diarrhoea.

Feature	Crohn's Disease	Ulcerative Colitis
Distribution	Any part of GI tract (mouth → anus). Most commonly terminal ileum and colon (ileocolonic ~40%)	Colon and rectum only. Continuous inflammation starting at rectum, extending proximally
Pattern	Transmural, skip lesions, cobblestoning	Mucosal and submucosal only, continuous, diffuse erythema and friability
Diarrhoea character	Watery or semi-formed. Bloody stool less common unless colonic involvement. Steatorrhoea if small bowel disease	Bloody diarrhoea with mucus is hallmark. Urgency, tenesmus, nocturnal symptoms
Complications	Strictures, fistulae (perianal, enterocutaneous, entero-enteric), abscesses, malnutrition	Toxic megacolon, massive haemorrhage, colorectal cancer risk (↑ after 8–10 years of extensive colitis)
Extra-intestinal manifestations	Both: arthritis (peripheral and axial), erythema nodosum, pyoderma gangrenosum, uveitis/episcleritis, primary sclerosing cholangitis (more common in UC)	Same spectrum; PSC more associated with UC
Serology	ASCA positive (60–70%), pANCA negative	pANCA positive (60–70%), ASCA negative
Gold standard diagnosis	Ileocolonoscopy + biopsies showing non-caseating granulomas, transmural inflammation. MR enterography for small bowel assessment	Colonoscopy + biopsies showing continuous mucosal inflammation, crypt abscesses, goblet cell depletion

IBD Severity Assessment

Mild–Moderate

Outpatient Managed

<4 stools/day, no blood (or intermittent), no systemic toxicity, ESR/CRP mildly elevated or normal. No weight loss >5%.

Setting: GP + Gastroenterologist outpatient

Moderate–Severe

Specialist Management

≥4 stools/day with blood, moderate abdominal pain, mild fever, ESR/CRP elevated, haemoglobin <100 g/L, weight loss 5–10%.

Setting: Gastroenterologist ± hospital inpatient

Severe / Fulminant

Hospital Admission Required

>6 bloody stools/day, temperature >38°C, HR >90 bpm, Hb <100 g/L, albumin <30 g/L. May include toxic megacolon (colon >6 cm on AXR).

Setting: Gastroenterology inpatient unit

Pharmacological Management

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Mesalazine (5-ASA)

Pentasa®, Salofalk®, Mesasal® · Aminosalicylate

Adult dose (UC) Mild–moderate: 1.5–3 g PO OD (oral) + 1 g PR OD (rectal, for distal disease)

Adult dose (Crohn's) Limited role; occasionally for mild ileo-caecal Crohn's (controversial evidence)

Maintenance 1–2 g PO OD long-term for UC

Renal adjustment Use with caution if eGFR <30; monitor renal function regularly

PBS status ⚠️ PBS Authority Required

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Prednisolone

Sone®, Panafcortelone® · Corticosteroid

Adult dose (induction) 40 mg PO OD for moderate–severe flare, weaned over 8 weeks (e.g., reduce by 5 mg/week)

Paediatric dose 1–2 mg/kg/day PO (max 40 mg), weaned over 8–12 weeks

Severe UC (hospital) IV hydrocortisone 100 mg QDS or IV methylprednisolone 60 mg OD

Duration Induction only — NOT for maintenance. Use steroid-sparing agents long-term

PBS status ✔ PBS General Benefit

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Azathioprine

Imuran® · Immunomodulator (thiopurine)

Adult dose 2–2.5 mg/kg/day PO OD. Start at 50 mg and titrate based on TPMT/NUDT15 genotype and tolerance

Monitoring FBC fortnightly for first 8 weeks, then 3-monthly. LFTs 3-monthly. TPMT/NUDT15 testing before initiation

Onset of effect 8–12 weeks (used as steroid-sparing maintenance agent)

PBS status ⚠️ PBS Authority Required

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Infliximab

Remicade®, Inflectra®, Renflexis® · Anti-TNFα biologic

Adult dose 5 mg/kg IV at weeks 0, 2, 6 (induction), then every 8 weeks (maintenance)

Indications Moderate–severe Crohn's disease and UC refractory to conventional therapy. Acute severe UC (accelerated induction: 5 mg/kg at day 0 and day 3 if non-response)

Pre-treatment Screen for TB (IGRA + CXR), hepatitis B (HBsAg, anti-HBc), varicella status. Exclude sepsis

PBS status 🔒 PBS Authority Required (Specialist only)

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Vedolizumab

Entyvio® · Anti-α4β7 integrin biologic

Adult dose 300 mg IV at weeks 0, 2, 6, then every 8 weeks. Subcutaneous maintenance option available (108 mg SC every 2 weeks)

Advantages Gut-selective mechanism — lower systemic immunosuppression risk. Preferred in patients with recurrent infections or malignancy history

PBS status 🔒 PBS Authority Required (Specialist only)

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Metronidazole + Ciprofloxacin

Flagyl® + Ciproxin® · Antibiotics (perianal Crohn's)

Adult dose Metronidazole 400 mg PO BD + Ciprofloxacin 500 mg PO BD for perianal fistulating Crohn's disease

Duration 4–8 weeks (monitor for peripheral neuropathy with prolonged metronidazole use)

PBS status ✔ PBS General Benefit

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Steroid dependency warning: Patients requiring more than two courses of corticosteroids per year, or who relapse on tapering, should be escalated to steroid-sparing agents (azathioprine, methotrexate, or biologics). Prolonged steroid use is associated with osteoporosis, diabetes, adrenal suppression, and increased infection risk.

IBD Monitoring Targets

Modern IBD management targets deep remission — clinical remission (symptom resolution) plus biochemical remission (normal CRP and faecal calprotectin <150 μg/g) plus endoscopic remission (mucosal healing on colonoscopy). Treatment decisions are increasingly guided by objective biomarkers rather than symptoms alone, given the discordance between symptom severity and mucosal inflammation.

Faecal calprotectin: Monitor every 3–6 months. Target <150 μg/g. Rising levels prompt treatment adjustment even in asymptomatic patients.
CRP: Monitor monthly during flares, every 3–6 months during remission.
Drug levels: Trough infliximab levels 3–7 μg/mL during maintenance. Anti-drug antibody testing if loss of response.
Colonoscopy: Surveillance colonoscopy for CRC screening in extensive UC/Crohn's colitis starting 8 years after diagnosis, every 1–3 years depending on risk factors.

C. difficile Infection & Chronic Diarrhoea

Clostridioides difficile Infection (CDI)

Clostridioides difficile infection is the leading cause of healthcare-associated diarrhoea in Australia, accounting for an estimated 15,000–20,000 bed-days per year. CDI occurs when disruption of normal colonic flora (most commonly by antibiotics) allows overgrowth of toxin-producing C. difficile strains. The organism produces toxins A (enterotoxin) and B (cytotoxin), which cause mucosal inflammation, fluid secretion, and pseudomembrane formation.

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Critical safety point: Never use antimotility agents (loperamide, codeine) in suspected or confirmed CDI. They impair toxin clearance, increase toxin contact with mucosa, and significantly increase the risk of toxic megacolon, colonic perforation, and death.

Risk Factor	Details
Antibiotic exposure	Any antibiotic within 12 weeks. Highest risk: clindamycin, fluoroquinolones, broad-spectrum cephalosporins, carbapenems
Proton pump inhibitors	Omeprazole, esomeprazole, pantoprazole — associated with increased CDI risk (consider deprescribing in hospital)
Age ≥65 years	Significantly increased risk of severe/fulminant CDI and mortality
Immunosuppression	Chemotherapy, solid organ transplant, IBD patients on immunomodulators/biologics, HIV
Hospitalisation	Prolonged inpatient stay, ICU admission, nasogastric feeding, GI surgery
Previous CDI	20–30% recurrence rate after first episode; higher after each subsequent episode

CDI Severity Classification & Treatment

Non-severe

Initial Episode — Mild/Moderate

Diarrhoea (≥3 unformed stools/day), WCC ≤15 × 10⁹/L, serum creatinine <1.5 × baseline, no peritonitis.

Setting: Ward / ambulatory

Severe

Initial Episode — Severe

WCC >15 × 10⁹/L, serum creatinine ≥1.5 × baseline, albumin <30 g/L. ± Abdominal tenderness.

Setting: Inpatient, consider HDU

Fulminant

Fulminant CDI

Hypotension, ileus, toxic megacolon, peritonitis, lactate >2.2 mmol/L, WCC >35 or <2 × 10⁹/L. High mortality risk.

Setting: ICU admission. Urgent surgical review

CDI Treatment Algorithm

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Vancomycin

Vancocin® · Glycopeptide antibiotic (oral)

Non-severe CDI Vancomycin 125 mg PO QDS for 10 days (first-line, replaces metronidazole per IDSA 2021/SHEA guidelines)

Severe CDI Vancomycin 125–500 mg PO QDS for 10 days. Consider vancomycin 500 mg QDS + metronidazole 500 mg IV TDS if ileus

Fulminant CDI Vancomycin 500 mg PO/NG QDS + metronidazole 500 mg IV TDS. Add vancomycin 500 mg in 100 mL saline PR QDS if ileus. Early surgical consultation for subtotal colectomy if non-response within 48–72 hours

Note Oral vancomycin is NOT absorbed systemically — high intracolonic concentration. IV vancomycin is ineffective for CDI

PBS status 🔒 PBS Authority Required

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Fidaxomicin

Dificid® · Macrolide antibiotic (narrow-spectrum)

Adult dose 200 mg PO BD for 10 days

Advantage Narrow-spectrum — does not significantly disrupt commensal flora. Lower recurrence rate than vancomycin (15% vs 25%)

Indication First-line alternative or preferred for patients at high risk of recurrence (age ≥65, immunocompromised, severe CDI). Can also use as vancomycin step-down

PBS status 🔒 PBS Authority Required

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Bezlotoxumab

Zinplava® · Anti-toxin B monoclonal antibody

Adult dose 10 mg/kg IV single dose (infused over 60 minutes) alongside standard-of-care antibiotic therapy

Indication Prevention of CDI recurrence in high-risk adults (age ≥65, immunocompromised, previous CDI episode, severe CDI)

PBS status 🔒 Not PBS-listed (Special Access Scheme available)

Recurrent CDI & Faecal Microbiota Transplantation (FMT)

Recurrent CDI (defined as recurrence of diarrhoea within 8 weeks of completing treatment for a prior episode) occurs in 20–30% of patients after first-line treatment and increases with each subsequent recurrence. Management involves:

First recurrence: Vancomycin 125 mg PO QDS for 10 days, then taper and pulse regimen (125 mg PO BD × 7 days → 125 mg PO OD × 7 days → 125 mg PO every 2–3 days for 2–8 weeks). OR fidaxomicin 200 mg PO BD for 10 days.
Second or subsequent recurrence: Faecal microbiota transplantation (FMT) is recommended by Australian and international guidelines. Delivered via colonoscopy, enema, or oral capsules. Success rates 80–90%. Available at major Australian tertiary centres (e.g., St Vincent's Melbourne, Royal Adelaide, Mater Brisbane).
Alternative: Vancozyme (fecal microbiota, live-jslm) oral capsules — recently TGA-approved for recurrent CDI. Check current availability and PBS status with hospital pharmacy.

Chronic Diarrhoea — Differential Diagnosis & Workup

Chronic diarrhoea (≥4 weeks) requires a structured, stepwise evaluation to identify the underlying cause and direct treatment. The following table outlines the major aetiologies, distinguishing features, and diagnostic approach.

Aetiology	Key Features	Investigation	Treatment
Coeliac disease	Chronic diarrhoea, bloating, weight loss, iron deficiency, dermatitis herpetiformis. Affects ~1 in 70 Australians	Anti-tTG IgA + total IgA. Positive → gastroscopy with duodenal biopsies (≥4 biopsies). HLA-DQ2/DQ8 to exclude	Strict lifelong gluten-free diet. Dietitian referral essential
Microscopic colitis	Watery, non-bloody diarrhoea in older adults (peak 60–70 years). F:M ratio 5:1. Normal macroscopic colonoscopy. Associated with PPIs, NSAIDs, SSRIs	Colonoscopy with random biopsies (must take biopsies even if mucosa appears normal). Collagenous vs lymphocytic subtype	Budesonide 9 mg PO OD for 6–8 weeks (induction), then 3–6 mg OD maintenance. First-line. ⚠️ PBS Authority Required
Bile acid malabsorption (BAM)	Watery diarrhoea, often worse after fatty meals. Post-cholecystectomy, post-ileal resection, or idiopathic. Under-recognised cause in Australia	SeHCAT scan (limited availability in AU) or therapeutic trial of cholestyramine. Elevated serum C4 or 7α-hydroxy-4-cholesten-3-one	Cholestyramine (Questran Lite®) 4 g PO OD–BD before meals. Titrate to response. ✔ PBS General Benefit
Pancreatic exocrine insufficiency	Steatorrhoea (bulky, pale, foul-smelling stools), weight loss, fat-soluble vitamin deficiency. Post-pancreatitis, pancreatic cancer, cystic fibrosis	Faecal elastase-1 (<200 μg/g). 72-hour faecal fat (>7 g/day abnormal). CT abdomen if structural cause suspected	Pancreatic enzyme replacement therapy (PERT): Creon® 25,000 units PO with meals. Titrate based on symptoms. ⚠️ PBS Authority Required
Medication-induced	Metformin (very common), magnesium-containing antacids, NSAIDs, colchicine, SSRIs/SNRIs, PPIs, acarbose, ARBs	Temporal relationship with medication initiation/change. Diagnosis of exclusion	Review and adjust medications. Trial cessation if safe and alternative available
IBS-D (functional)	Recurrent abdominal pain associated with defecation (Rome IV criteria). Onset ≥6 months ago. No nocturnal symptoms, no weight loss, no blood. Often young adults	Diagnosis of exclusion. FBC, CRP, coeliac serology, faecal calprotectin normal. Consider FIT if age >45	Low FODMAP diet (dietitian-guided), loperamide PRN, eluxadoline (Viberzi® — specialist), rifaximin 550 mg TDS for 14 days (specialist use)

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Giardia lamblia: Consider in chronic diarrhoea with bloating, flatulence, and malabsorption, especially with travel history (Southeast Asia, Papua New Guinea), childcare exposure, or drinking untreated water. Diagnosis: stool Giardia antigen (EIA) or multiplex PCR. Treatment: tinidazole 2 g PO single dose (first-line) or metronidazole 400 mg PO TDS for 5–7 days. Both ✔ PBS General Benefit.

Special Populations

🤰 Pregnancy

Oral rehydration ORS is first-line. Avoid bismuth subsalicylate (Pepto-Bismol®) — aspirin component contraindicated in pregnancy.

Loperamide Generally considered safe in pregnancy (Category B1). Short courses for non-bloody diarrhoea.

Antibiotics Azithromycin (Category B1) is first-line for bacterial gastroenteritis in pregnancy. Ciprofloxacin (Category B3) — avoid if possible. Metronidazole (Category B2) — avoid in first trimester.

IBD management 5-ASA agents and azathioprine are considered safe in pregnancy. Biologics (infliximab, vedolizumab) can be continued until 22–24 weeks gestation. Active IBD flares in pregnancy require urgent specialist management.

Key risk Listeriosis (Listeria monocytogenes) from contaminated food — can cause miscarriage/stillbirth. Avoid soft cheeses, deli meats, pre-prepared salads when immunocompromised or pregnant.

👶 Paediatrics

Dehydration assessment Use the WHO dehydration scale. Mild (<5%): alert, thirsty. Moderate (5–10%): restless, irritable, sunken eyes, skin turgor reduced. Severe (>10%): lethargic, unconscious, weak pulse.

ORS WHO-ORS: 50–100 mL/kg over 4 hours for moderate dehydration. Gastrolyte® available as sachets or frozen ice blocks (preferred by children). Avoid fruit juice, soft drinks, flat lemonade (high osmolality).

Ondansetron 4–8 mg orally disintegrating wafer for children >2 years (weight-based: 2–4 mg for 8–15 kg). Reduces vomiting, facilitates ORS intake, reduces ED admissions. ✔ PBS General Benefit (ODT formulation).

Loperamide Contraindicated in children <12 years. Risk of paralytic ileus, toxic megacolon, and respiratory depression.

Rotavirus vaccination On the NIP: Rotarix® (2 doses at 2 and 4 months) or RotaTeq® (3 doses at 2, 4, 6 months). Significantly reduces rotavirus hospitalisations in Australia.

Paediatric IBD Increasing incidence in Australia. More aggressive phenotype than adult-onset. Requires specialist paediatric gastroenterology management. Exclusive enteral nutrition (EEN) is first-line induction for paediatric Crohn's disease (8-week liquid diet, equivalent efficacy to corticosteroids with mucosal healing benefit).

👴 Elderly (≥65 years)

Dehydration risk Significantly higher risk due to reduced thirst response, polypharmacy, and comorbidities. Lower threshold for IV rehydration and hospital assessment.

C. difficile risk Age ≥65 is an independent risk factor for CDI, severe CDI, and CDI-related mortality. Maintain high index of suspicion with any antibiotic-associated diarrhoea in elderly patients.

Medication review Polypharmacy is a common cause. Review metformin, PPIs, laxatives, NSAIDs, colchicine, magnesium, ARBs. Deprescribe where possible.

Microscopic colitis Peak incidence in 60–70 year age group. Often misdiagnosed as IBS. Biopsies required during colonoscopy for diagnosis (mucosa appears normal macroscopically).

Red flags New-onset bloody diarrhoea in patients >50 years requires urgent colonoscopy to exclude colorectal malignancy, ischaemic colitis, or diverticular disease.

🫘 Renal Impairment

Dehydration Diarrhoea-induced dehydration can precipitate acute kidney injury (AKI) or worsen existing CKD. Monitor UEC closely. IV fluid resuscitation with isotonic crystalloid (Hartmann's preferred; avoid lactate if L-lactic acidosis).

Electrolyte monitoring Watch for hypokalaemia, hypomagnesaemia, hyponatraemia. Replace as needed. Particularly dangerous in patients on digoxin or those with cardiac comorbidities.

Drug dose adjustments Metronidazole: no adjustment needed. Ciprofloxacin: reduce dose if eGFR <30 (250 mg BD). Vancomycin oral: no renal adjustment (not absorbed). Azithromycin: no adjustment. Loperamide: no adjustment.

🫁 Hepatic Impairment

Diarrhoea in cirrhosis May precipitate hepatic encephalopathy (increased ammonia production from gut bacterial overgrowth and protein malabsorption). Consider lactulose to maintain 2–3 soft stools/day. Monitor ammonia levels if encephalopathy suspected.

Drug considerations Metronidazole: reduce dose in severe hepatic impairment (Child-Pugh C). Azithromycin: caution in severe liver disease. Loperamide: caution — reduced first-pass metabolism may increase CNS effects.

🛡️ Immunocompromised

Broader differential Include CMV colitis, Cryptosporidium, Microsporidium, Mycobacterium avium complex (MAC), Isospora belli, and drug-induced diarrhoea (mycophenolate, everolimus, irinotecan). HIV patients with CD4 <200 require extended stool evaluation.

CMV colitis Suspect in transplant recipients or HIV+ patients with bloody diarrhoea, high fever, and abdominal pain. Diagnose with colonoscopic biopsy (histopathology + CMV immunohistochemistry). Treat: IV ganciclovir 5 mg/kg BD for 2–3 weeks → valganciclovir 900 mg PO BD.

IBD on biologics Patients on anti-TNF or vedolizumab are at increased risk of opportunistic infections. Always consider opportunistic causes before empiric corticosteroid escalation for presumed IBD flare.

Neutropenic enterocolitis Typhlitis — necrotising inflammation of caecum in neutropenic patients (ANC <0.5 × 10⁹/L). Right iliac fossa pain + bloody diarrhoea + neutropenia. CT abdomen for diagnosis. Broad-spectrum antibiotics (piperacillin-tazobactam) + supportive care. Urgent haematology review.

Aboriginal and Torres Strait Islander Health Considerations

Aboriginal and Torres Strait Islander Health

Disproportionate burden

Aboriginal and Torres Strait Islander peoples experience gastroenteritis hospitalisation rates 3–5 times higher than non-Indigenous Australians, with the greatest disparity in children under 5 years and those living in remote and very remote communities. Invasive gastroenteritis (requiring hospitalisation) is particularly high in the Northern Territory, with rates up to 7 times the national average in some remote communities.

Environmental determinants

Overcrowded housing, limited access to clean water and functioning sanitation infrastructure, and reduced access to hygiene facilities contribute significantly to the burden of diarrhoeal disease. The Australian Government's Closing the Gap framework includes targets for improved housing and infrastructure, but progress has been uneven. Trachoma and gastroenteritis share overlapping environmental risk factors.

Access to healthcare

Remote communities often rely on Aboriginal Community Controlled Health Organisations (ACCHOs) with visiting GP and specialist services. Delays in presentation due to geographic remoteness can lead to severe dehydration, particularly in children and elderly patients. Aeromedical retrieval (RFDS, CareFlight) is critical for severe cases. Telehealth-supported assessment has improved triage capacity in many remote NT and WA communities.

Zoonotic and environmental infections

Campylobacter and Salmonella rates are significantly higher in remote Indigenous communities, linked to animal husbandry (dogs, cats), food storage limitations in hot climates, and limited cold-chain infrastructure. Cattle-associated STEC infections also occur in pastoral communities. Environmental enteropathy (subclinical chronic gut inflammation from repeated enteric infections) contributes to growth faltering and impaired cognitive development in children.

Giardia and parasitic infections

Giardia lamblia is endemic in many remote Aboriginal and Torres Strait Islander communities, particularly in the NT and northern WA. Chronic giardiasis contributes to malabsorption, failure to thrive in children, and chronic diarrhoea in adults. Mass drug administration programs (MDAs) for Strongyloides and other soil-transmitted helminths are in place in some regions and should be considered for patients presenting with diarrhoea and eosinophilia.

Cultural safety in management

Engage Aboriginal and Torres Strait Islander health workers and liaison officers in all aspects of care. Use culturally appropriate health education materials (available through ACCHOs and the Lowitja Institute). "Sorry Business" and cultural obligations may affect treatment adherence and follow-up attendance. Facilitate flexible appointment scheduling and community-based follow-up where possible.

Prevention strategies

Rotavirus vaccination coverage is high in Aboriginal and Torres Strait Islander children (>85% completed schedule). Hand hygiene promotion, safe water programs, housing improvement initiatives, and community-based gastroenteritis education campaigns (e.g., "Wash 'em, cook 'em, cool 'em" messaging) are critical. The Australian Institute of Health and Welfare (AIHW) and the Menzies School of Health Research provide ongoing surveillance and intervention data for diarrhoeal disease in Indigenous populations.

📚 References

1. Australian Institute of Health and Welfare (AIHW). Gastrointestinal infection in Australia — Aboriginal and Torres Strait Islander people. Canberra: AIHW; 2023.
2. Communicable Diseases Network Australia (CDNA). Australian national notifiable diseases case definitions — Gastrointestinal infections. Australian Government Department of Health and Aged Care; 2023.
3. GBD 2019 Diarrhoeal Diseases Collaborators. The global, regional, and national burden of diarrhoeal diseases, 1990–2019. Lancet Infect Dis. 2023;23(5):594–611.
4. Kelly CP, LaMont JT. Clostridioides difficile infection in adults: Clinical manifestations and diagnosis. UpToDate. Wolters Kluwer; 2024.
5. Lamb CA, Kennedy NA, Raine T, et al. British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults. Gut. 2019;68(Suppl 3):s1–s106.
6. McDonald LC, Gerding DN, Johnson S, et al. Clinical practice guidelines for Clostridioides difficile infection in adults and children: 2017 update by IDSA and SHEA. Clin Infect Dis. 2018;66(7):e1–e48.
7. Menzies School of Health Research. Childhood gastroenteritis and environmental health in remote Indigenous communities. Darwin: Menzies School of Health Research; 2022.
8. National Health and Medical Research Council (NHMRC). Australian guidelines for the prevention and control of infection in healthcare. Canberra: NHMRC; 2019.
9. RACGP. Prescribing drugs of dependence in general practice, Part B: Opioids — antimotility agents and diarrhoea management. Melbourne: Royal Australian College of General Practitioners; 2022.
10. Torres J, Bonovas S, Doherty G, et al. ECCO guidelines on therapeutics in Crohn's disease: Medical treatment. J Crohns Colitis. 2020;14(1):4–22.
11. Rubin DT, Ananthakrishnan AN, Siegel CA, et al. ACG clinical guideline: Ulcerative colitis in adults. Am J Gastroenterol. 2019;114(3):384–413.
12. Shane AL, Mody RK, Crump JA, et al. 2017 Infectious Diseases Society of America clinical practice guidelines for the diagnosis and management of infectious diarrhoea. Clin Infect Dis. 2017;65(12):e45–e80.
13. TGA (Therapeutic Goods Administration). Vedolizumab and infliximab — Product Information (Australian approved). Department of Health and Aged Care; 2024.
14. Kirk MD, Pires SM, Black RE, et al. World Health Organization estimates of the global and regional disease burden of 22 foodborne bacterial, protozoal, and viral diseases, 2010. PLoS Med. 2015;12(12):e1001921.

for PBS scripts. Utilise ACCHS pharmacies and Remote Area Aboriginal Health Worker programs for medication supply in remote areas. Avoid initiating benzodiazepines; support holistic pain management including community-based exercise programs.

Preventive health

Promote bone health: encourage vitamin D supplementation (1000 IU daily in deficient individuals), smoking cessation support, reduction of alcohol intake, and weight-bearing exercise. MBS Item 715 health checks provide a structured opportunity to assess bone health, screen for osteoporosis risk factors, and discuss musculoskeletal health in a culturally safe context.

Quick Reference: Differential Diagnosis at a Glance

Costovertebral dysfunction

Paracetamol ± NSAID; manual therapy

2–6 weeks

Provocable on palpation; no red flags

Thoracic compression fracture

Paracetamol; ± calcitonin; DXA + osteoporosis Rx

6–12 weeks healing

Elderly; osteoporosis; acute onset

ACS (posterior MI)

Aspirin 300 mg, GTN, heparin; urgent PCI

Time-critical

ECG, troponin; CV risk factors

Aortic dissection

IV labetalol; urgent CT aortogram; surgery (Type A)

Time-critical

Tearing pain; BP differential >20 mmHg

Vertebral osteomyelitis

IV antibiotics (vancomycin + ceftriaxone initially); ID consult

6 weeks IV antibiotics

Fever, elevated CRP, IV drug use

Biliary colic / cholecystitis

Paracetamol ± morphine; lap cholecystectomy

Surgical within 72 h (cholecystitis)

RUQ/infrascapular; post-prandial; RUQ US

📚 References

1. Briggs AM, Smith AJ, Straker LM, Bragge P. Thoracic spine pain in the general population: prevalence, incidence and associated factors in children, adolescents and adults. A systematic review. BMC Musculoskelet Disord. 2009;10:77.
2. National Health and Medical Research Council (NHMRC). Evidence-based management of acute musculoskeletal pain. Canberra: NHMRC; 2003 (updated 2020).
3. Australian Institute of Health and Welfare (AIHW). Aboriginal and Torres Strait Islander Health Performance Framework: Summary report 2023. Canberra: AIHW; 2023.
4. Deyo RA, Rainville J, Kent DL. What can the history and physical examination tell us about low back pain? JAMA. 1992;268(6):760–765.
5. Stochkendahl MJ, Kjaer P, Hartvigsen J, et al. National Clinical Guidelines for non-surgical treatment of patients with recent onset low back pain or lumbar radiculopathy. Europ Spine J. 2018;27(1):60–75.
6. Erwin WM, Jackson PC, Homonko DA. Innervation of the human costovertebral joint: implications for clinical back pain syndromes. J Manipulative Physiol Ther. 2000;23(6):395–403.
7. Royal Australian College of General Practitioners (RACGP). Guidelines for preventive activities in general practice. 9th edn. Melbourne: RACGP; 2018 (updated 2023).
8. Hirsch JA, Singh V, Falco FJE, et al. Thoracic facet joint interventions. Pain Physician. 2016;19(4):E581–E593.
9. Erwin WM, Jackson PC. The costovertebral joint: anatomy, biomechanics, and clinical significance in thoracic back pain syndromes. J Can Chiropr Assoc. 2003;47(2):112–120.
10. Strayer RJ, Gunnerson JM, Brown LH, et al. Aortic dissection: clinical features, diagnosis, and management. Aust Crit Care. 2019;32(2):144–153.
11. Ombregt L. A system of orthopaedic medicine. 3rd edn. Edinburgh: Churchill Livingstone Elsevier; 2013. Chapter 18: Thoracic spine.
12. Lin CC, Chen KH, Li DM, et al. Characteristics and outcomes of patients presenting with thoracic back pain to the emergency department. Emerg Med Australas. 2020;32(5):805–811.

for PBS-listed medicines at participating pharmacies.

Cultural safety

Engagement with Aboriginal Community Controlled Health Organisations (ACCHOs) is essential. Cultural safety training for non-Indigenous clinicians, use of Aboriginal Health Workers and Liaison Officers, and incorporation of traditional healing practices alongside Western medicine improve treatment adherence and outcomes. Avoidance of eye contact, respect for gender-sensitive examination practices, and understanding of sorry business protocols are critical elements of culturally safe care.

Medication adherence

Complex DMARD regimens with frequent monitoring requirements present adherence challenges. Long-acting depot injections (e.g., methotrexate SC) may improve adherence compared to oral regimens. Community pharmacy partnerships through the Indigenous Pharmacy Programmes improve medication management.

Specific conditions

Rheumatic heart disease (RHD) requires secondary prophylaxis with benzathine penicillin G (BPG) 1.2 MU IM every 3–4 weeks for a minimum of 10 years or until age 21 (whichever is longer). RHD registers (e.g., NT RHD Register) facilitate recall and follow-up. The Australian RHD Endgame Strategy targets elimination by 2031.

Referral pathways

Referral through ACCHOs and Aboriginal Hospital Liaison Officers (AHLOs) improves engagement. The Specialist Outreach Assistance Programme provides funded specialist visits to remote communities. NT, WA, and QLD have specific rheumatology outreach programmes targeting Indigenous communities.

📚 References

1. Australian Institute of Health and Welfare (AIHW). Autoimmune disease in Australia. Cat. no. PHE 312. Canberra: AIHW; 2023.
2. Fraenkel L, Bathon JM, England BR, et al. 2021 American College of Rheumatology guideline for the treatment of rheumatoid arthritis. Arthritis Care Res. 2021;73(7):924–939.
3. Fanouriakis A, Kostopoulou M, Alber K, et al. 2019 update of the EULAR recommendations for the management of systemic lupus erythematosus. Ann Rheum Dis. 2019;78(6):736–745.
4. Chung SA, Langford CA, Maz M, et al. 2021 American College of Rheumatology/Vasculitis Foundation guideline for the management of antineutrophil cytoplasmic antibody-associated vasculitis. Arthritis Care Res. 2021;73(11):1583–1599.
5. Smolen JS, Landewé RBM, Bijlsma JWJ, et al. EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2022 update. Ann Rheum Dis. 2023;82(1):3–18.
6. Australian Technical Advisory Group on Immunisation (ATAGI). Australian Immunisation Handbook. Australian Government Department of Health; 2024. Available from: immunisationhandbook.health.gov.au.
7. Rheumatic Heart Disease Australia (RHDAustralia). The 2020 Australian guideline for prevention, diagnosis, and management of acute rheumatic fever and rheumatic heart disease. 3rd ed. Darwin: Menzies School of Health Research; 2020.
8. Pharmaceutical Benefits Scheme (PBS). PBS Schedule. Australian Government Department of Health. Available from: pbs.gov.au. Accessed 2024.
9. Agarwal S, Cunnington J, Nossent J. Autoimmune disease in Indigenous Australians: a systematic review. Int J Rheum Dis. 2021;24(12):1487–1498.
10. Pisetsky DS. Antinuclear antibody testing — misunderstood or misused? Clin Immunol. 2023;255:109717.
11. Bertsias GK, Tektonidou M, Amoura Z, et al. Joint European League Against Rheumatism and European Renal Association–European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of adult and paediatric lupus nephritis. Ann Rheum Dis. 2012;71(11):1771–1782.
12. Ledingham J, Deighton C; British Society for Rheumatology Standards, Audit and Guidelines Working Group. Update on the British Society for Rheumatology guidelines for prescribing TNFα blockers in adults with rheumatoid arthritis. Rheumatology. 2005;44(2):155–158.
13. National Health and Medical Research Council (NHMRC). National statement on ethical conduct in human research. Canberra: NHMRC; 2023 (updated).

for PBS-listed medicines at participating pharmacies.

Cultural safety

Medication adherence

Specific conditions

Referral pathways

📚 References

1. Australian Institute of Health and Welfare (AIHW). Autoimmune disease in Australia. Cat. no. PHE 312. Canberra: AIHW; 2023.
2. Fraenkel L, Bathon JM, England BR, et al. 2021 American College of Rheumatology guideline for the treatment of rheumatoid arthritis. Arthritis Care Res. 2021;73(7):924–939.
3. Fanouriakis A, Kostopoulou M, Alber K, et al. 2019 update of the EULAR recommendations for the management of systemic lupus erythematosus. Ann Rheum Dis. 2019;78(6):736–745.
4. Chung SA, Langford CA, Maz M, et al. 2021 American College of Rheumatology/Vasculitis Foundation guideline for the management of antineutrophil cytoplasmic antibody-associated vasculitis. Arthritis Care Res. 2021;73(11):1583–1599.
5. Smolen JS, Landewé RBM, Bijlsma JWJ, et al. EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2022 update. Ann Rheum Dis. 2023;82(1):3–18.
6. Australian Technical Advisory Group on Immunisation (ATAGI). Australian Immunisation Handbook. Australian Government Department of Health; 2024. Available from: immunisationhandbook.health.gov.au.
7. Rheumatic Heart Disease Australia (RHDAustralia). The 2020 Australian guideline for prevention, diagnosis, and management of acute rheumatic fever and rheumatic heart disease. 3rd ed. Darwin: Menzies School of Health Research; 2020.
8. Pharmaceutical Benefits Scheme (PBS). PBS Schedule. Australian Government Department of Health. Available from: pbs.gov.au. Accessed 2024.
9. Agarwal S, Cunnington J, Nossent J. Autoimmune disease in Indigenous Australians: a systematic review. Int J Rheum Dis. 2021;24(12):1487–1498.
10. Pisetsky DS. Antinuclear antibody testing — misunderstood or misused? Clin Immunol. 2023;255:109717.
11. Bertsias GK, Tektonidou M, Amoura Z, et al. Joint European League Against Rheumatism and European Renal Association–European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of adult and paediatric lupus nephritis. Ann Rheum Dis. 2012;71(11):1771–1782.
12. Ledingham J, Deighton C; British Society for Rheumatology Standards, Audit and Guidelines Working Group. Update on the British Society for Rheumatology guidelines for prescribing TNFα blockers in adults with rheumatoid arthritis. Rheumatology. 2005;44(2):155–158.
13. National Health and Medical Research Council (NHMRC). National statement on ethical conduct in human research. Canberra: NHMRC; 2023 (updated).