Allergic Disorders Including Hay Fever

Last updated 1 Jun 2026 · Immunology / Allergy

📋 Key Information Summary

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Allergic disorders affect ~20% of Australians and are the most common chronic conditions managed in general practice, with significant morbidity and healthcare utilisation.
IgE-mediated reactions are rapid (minutes to 2 hours), involve mast-cell and basophil degranulation, and can cause anaphylaxis; non-IgE reactions are delayed (hours to days) and T-cell mediated, presenting with GI symptoms, eczema flares or FPIES.
Peanut allergy is now the most common cause of fatal food-related anaphylaxis in Australia; egg allergy is the most common infant food allergy; latex allergy affects healthcare workers and spina bifida patients.
Anaphylaxis requires immediate intramuscular adrenaline (anterolateral thigh) — EpiPen® Jr 150 µg (<20 kg) or EpiPen® 300 µg (≥20 kg); second dose at 5 minutes if no response.
All ASCIA Action Plans for Anaphylaxis must be completed, reviewed annually, and provided to schools, childcare, and workplaces alongside training on autoinjector use.
Allergic rhinitis (hay fever) affects ~18% of Australian adults; intranasal corticosteroids are first-line pharmacotherapy; allergen avoidance and sublingual immunotherapy (SLIT) address the underlying cause.
Skin prick testing (SPT) is the gold-standard office-based test for IgE-mediated allergy; specific IgE (RAST/ImmunoCAP) is useful when SPT is contraindicated or results are equivocal.
Serum tryptase drawn 1–2 hours post-reaction (and baseline) confirms mast-cell degranulation and supports a diagnosis of anaphylaxis.
Peanut oral immunotherapy (OIT) with Palforzia® (powderised peanut) is now TGA-registered in Australia for children and adolescents 4–17 years with confirmed peanut allergy.
Allergen immunotherapy (sublingual or subcutaneous) is the only disease-modifying treatment for allergic rhinitis and venom allergy, reducing symptom burden and preventing asthma development.
Aboriginal and Torres Strait Islander peoples have higher rates of undiagnosed allergic disease, anaphylaxis hospitalisation, and reduced access to specialist allergy services, particularly in remote communities.
Drug and chemical allergies must be documented in the patient's My Health Record and communicated across all care transitions; perioperative latex allergy alerts are critical for surgical patients.
Biphasic anaphylaxis occurs in up to 20% of cases; all patients with anaphylaxis require a minimum 4-hour observation period in a facility capable of managing cardiorespiratory arrest.
Refer to a clinical immunologist/allergist for confirmed or suspected anaphylaxis, venom allergy, uncertain food allergy diagnosis, consideration of immunotherapy, or drug allergy evaluation.

Introduction & Australian Epidemiology

Allergic disorders encompass a spectrum of immune-mediated hypersensitivity reactions that are increasingly prevalent across all age groups in Australia. General practitioners are frequently the first point of contact for patients presenting with allergic symptoms, and timely diagnosis, risk stratification, and management are essential to prevent morbidity and mortality — particularly from anaphylaxis.

Australia has one of the highest rates of allergic disease globally. The National Allergy Strategy (2019–2024), developed by the Australasian Society of Clinical Immunology and Allergy (ASCIA) and Allergy & Anaphylaxis Australia (A&AA), highlights the significant burden on the healthcare system and the need for coordinated primary care management.

Condition	Estimated Australian Prevalence	Key Data
Allergic rhinitis (hay fever)	~18% of adults; ~12% of children	Most common allergic condition; peak onset 15–34 years
Food allergy	~10% of infants; ~5% of adults	Highest per-capita rate worldwide; egg and cow's milk most common in infants; peanut and tree nut in older children
Anaphylaxis	~1 in 300 lifetime prevalence	Hospitalisations rising ~7% per year; food triggers most common in children, insect venom in adults
Atopic dermatitis (eczema)	~20% of infants; ~10% of adults	Strong risk factor for subsequent food allergy and allergic march
Drug allergy (labelled)	~10–15% report a drug allergy	Most reported penicillin allergies are not true allergy upon formal testing
Insect venom allergy	~1–3% systemic reactions to stings	Jack jumper ants (SA, TAS, VIC), bull ants, honeybees, paper wasps

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Rising anaphylaxis burden: Australia experienced a 5.7-fold increase in anaphylaxis hospital admissions between 1994 and 2014 (AIHW data). Food-induced anaphylaxis in children aged 0–4 years is the leading cause of anaphylaxis-related ED presentations nationally. Early allergist referral and adrenaline autoinjector prescription are critical safety measures.

The allergic march describes the typical natural history: atopic dermatitis and food allergy in infancy, followed by allergic rhinitis and asthma in later childhood. Early identification and management of allergic conditions in primary care may alter this trajectory. GPs should screen for atopic comorbidities and provide anticipatory guidance to families.

The National Allergy Strategy

The National Allergy Strategy, funded by the Australian Government Department of Health, provides standardised pathways for allergy management in primary care. Key initiatives include the ASCIA Action Plans, the Nip Allergies in the Bub program for infant allergy prevention, and standardised adrenaline autoinjector training for schools and early childhood services.

IgE vs Non-IgE Food Reactions

Distinguishing IgE-mediated from non-IgE-mediated food reactions is a fundamental clinical skill in allergy medicine. The mechanism dictates the timing, clinical presentation, diagnostic approach, and long-term management.

IgE-Mediated Food Reactions

IgE-mediated reactions involve prior sensitisation to a food allergen, production of allergen-specific IgE, and binding to high-affinity FcεRI receptors on mast cells and basophils. Upon re-exposure, cross-linking of surface-bound IgE triggers rapid degranulation, releasing histamine, tryptase, leukotrienes, and prostaglandins.

Timing: Rapid onset — typically within 15–30 minutes, almost always within 2 hours of ingestion.
Organs affected: Skin (urticaria, angioedema — most common), upper airway (laryngeal oedema, stridor), lower airway (bronchospasm, wheeze), cardiovascular (hypotension, tachycardia), gastrointestinal (vomiting, abdominal pain).
Diagnosis: Skin prick testing (SPT), specific IgE (sIgE / ImmunoCAP), component-resolved diagnostics (CRD), and supervised oral food challenges.
Common triggers: Peanut, tree nut, egg, cow's milk, wheat, soy, fish, shellfish, sesame, kiwi fruit.
Management: Strict allergen avoidance, adrenaline autoinjector prescription, ASCIA Action Plan, and consideration of allergen immunotherapy (OIT or SCIT).

Non-IgE-Mediated Food Reactions

Non-IgE-mediated reactions are predominantly T-cell driven, with delayed onset and different clinical patterns. These reactions are generally not life-threatening but cause significant morbidity, particularly in infants and young children.

Timing: Delayed — typically 2–48 hours after ingestion, sometimes up to 72 hours.
Common conditions: Food protein-induced enterocolitis syndrome (FPIES), food protein-induced allergic proctocolitis (FPIAP), food protein-induced enteropathy, eosinophilic oesophagitis (EoE), and non-IgE-mediated atopic dermatitis.
FPIES: Presents with profuse vomiting ± pallor and lethargy 1–4 hours after ingestion; most commonly triggered by cow's milk, soy, rice, and oat in infants. Can cause hypovolaemic shock if unrecognised. No urticaria or angioedema.
FPIAP: Bloody stools in otherwise well infants, typically on cow's milk or soy protein; self-resolving with dietary elimination.
Diagnosis: Primarily clinical; SPT and sIgE are typically negative. Elimination diets followed by clinician-supervised food challenges confirm diagnosis. Endoscopy with biopsy for EoE.
Management: Dietary elimination under dietitian supervision, with planned reintroduction. Adrenaline autoinjectors generally not required unless concurrent IgE-mediated allergy confirmed.

Feature	IgE-Mediated	Non-IgE-Mediated
Mechanism	Mast-cell / basophil degranulation via surface-bound IgE	T-cell mediated, eosinophilic, or mixed immune response
Onset	Minutes to 2 hours	2–72 hours
Typical features	Urticaria, angioedema, vomiting, anaphylaxis	Bloody stools, chronic vomiting, eczema flares, FPIES
SPT / sIgE	Positive	Negative (usually)
Adrenaline autoinjector	Yes, if systemic features or anaphylaxis history	Not routinely indicated
Natural history	Often persistent (peanut, tree nut); may resolve (egg, milk, wheat, soy)	Usually resolves by age 3–5 years (FPIES, FPIAP)

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Mixed IgE and non-IgE allergy: Some conditions feature both pathways (e.g., eosinophilic oesophagitis, atopic dermatitis with food triggers). Component-resolved diagnostics (CRD) can help clarify risk — for example, Ara h 2 sIgE for peanut indicates higher anaphylaxis risk than whole peanut sIgE alone.

Peanut, Egg & Latex Allergy

Peanut Allergy

Peanut allergy is the most common cause of fatal and near-fatal food-related anaphylaxis in Australia. Approximately 3% of Australian infants have a challenge-proven peanut allergy. Unlike egg and milk allergy, peanut allergy persists into adulthood in ~80% of cases. The HealthNuts study (Murdoch Children's Research Institute) demonstrated that early introduction of peanut in high-risk infants significantly reduces the development of peanut allergy.

Diagnosis: SPT wheal ≥8 mm in children <2 years is highly predictive; in older children and adults, sIgE and CRD (Ara h 2) are preferred. Component Ara h 2 sIgE >0.35 kU/L has high positive predictive value for clinical allergy.
Management: Strict avoidance, adrenaline autoinjector, ASCIA Action Plan, annual allergist review.
Oral immunotherapy (OIT): Palforzia® (AR101, powderised peanut) is TGA-registered for children/adolescents 4–17 years. Administered as escalating doses under specialist supervision to achieve desensitisation (increased reaction threshold). Maintenance dose 300 mg/day peanut protein. Does not cure allergy — requires ongoing daily dosing.
Early introduction (prevention): ASCIA recommends introduction of well-cooked egg from ~6 months and smooth peanut butter/paste from around 6 months of age in all infants, including those with severe eczema or egg allergy, ideally under medical guidance.

Egg Allergy

Egg allergy is the most common food allergy in Australian infants, affecting ~9% at 12 months (HealthNuts study). The majority (~70%) outgrow egg allergy by age 16 years, though persistence is more likely in those with high sIgE levels or concurrent asthma.

Forms: Raw egg allergy (most common — tolerates baked egg) vs whole egg allergy (reacts to baked and raw).
Baked egg tolerance: Children who tolerate baked egg (e.g., in muffins at 180°C for 30 minutes) have improved quality of diet and are more likely to outgrow egg allergy. Baked egg challenges should be performed under medical supervision.
Implications for vaccination: Most egg-allergic children can safely receive influenza vaccine (egg-grown) and MMR/varicella vaccines. Only severe (anaphylactic) egg allergy warrants vaccination in a monitored setting. Q Fever vaccine (Q-Vax®) is contraindicated in egg allergy.
Orvaten® (egg OIT): Not yet TGA-registered but available in specialist clinical trials in Australia.

Latex Allergy

Natural rubber latex (NRL) allergy is an important occupational and iatrogenic allergy in Australia. Prevalence in the general population is <1%, but high-risk groups include healthcare workers (5–17%), patients with spina bifida (up to 72%), patients with urogenital anomalies requiring repeated catheterisation, and patients with multiple surgical histories.

Mechanism: IgE-mediated (Type I) hypersensitivity to NRL proteins — can cause anaphylaxis during surgery or examination. Also contact dermatitis (Type IV) to rubber accelerators — this is not IgE-mediated.
Cross-reactivity: Latex-fruit syndrome — cross-reactive IgE epitopes in banana, avocado, kiwi, chestnut, and passionfruit (Hev b 5, Hev b 6 homologues).
Diagnosis: SPT with latex extract (gold standard); sIgE to NRL (ImmunoCAP) — available in Australia. Skin testing reagents may be limited in some centres — refer to specialist.
Management: Strict NRL avoidance; latex-free surgical environments; MediAlert® bracelet; pre-medication with corticosteroids and antihistamines does NOT reliably prevent anaphylaxis — latex avoidance is the cornerstone.
Latex-free alternatives: Nitrile or vinyl gloves, silicone-based urinary catheters, latex-free tourniquets. All Australian hospitals now maintain latex-free kits for known allergy.

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Perioperative latex anaphylaxis: Latex allergy must be flagged in pre-anaesthetic assessments. Intraoperative anaphylaxis from latex is often unrecognised. All patients with spina bifida, repeated catheterisation, or multiple prior surgeries should be screened for latex allergy and have perioperative allergy alerts documented in their electronic medical record.

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Palforzia® (AR101 — Powderised Peanut)

Aimmune Therapeutics · Peanut oral immunotherapy

Indication Peanut allergy desensitisation in patients 4–17 years with confirmed diagnosis

Dose escalation Day 1: 0.5 mg → 1 mg → 1.5 mg → 3 mg → 6 mg → 12 mg → 20 mg (under supervision); then 12 dose-escalation levels over ~22 weeks

Maintenance dose 300 mg peanut protein PO daily (mixed into semi-solid food)

Setting Initiation and each dose escalation under specialist supervision in a facility with anaphylaxis management capability

PBS status ✘ Not PBS-listed TGA-registered; privately funded or clinical trial

Anaphylaxis Kit & Management

Anaphylaxis is a severe, potentially life-threatening systemic hypersensitivity reaction requiring immediate recognition and treatment. In Australia, the ASCIA Action Plan for Anaphylaxis is the standardised management document, and all patients with a confirmed allergy that could cause anaphylaxis should carry an adrenaline autoinjector and have a current action plan.

Recognising Anaphylaxis

Anaphylaxis is highly likely when any one of the following criteria is met:

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Criterion 1: Acute onset of skin or mucosal symptoms (urticaria, flushing, angioedema) PLUS respiratory compromise (dyspnoea, wheeze, stridor, hypoxia) OR cardiovascular compromise (hypotension, syncope, incontinence)
Criterion 2: Two or more of the following occurring rapidly after exposure to a likely allergen: skin/mucosal symptoms, respiratory compromise, cardiovascular compromise, persistent GI symptoms (crampy abdominal pain, vomiting)
Criterion 3: Hypotension after exposure to a known allergen for that patient (age-specific: SBP <70 mmHg in infants, <70 + (2 × age) mmHg in children 1–10 years, <90 mmHg in adults)

Acute Management — The ASCIA Action Plan

Lay flat & call 000

Position patient supine with legs elevated (unless respiratory distress — allow to sit). Call 000 for ambulance. Remove allergen source if possible (e.g., stop IV medication, remove insect sting).

Adrenaline IM — anterolateral thigh

Administer adrenaline autoinjector or draw up from ampoule. Site: mid-outer thigh (through clothing if needed). Do NOT delay for any other treatment.

Repeat at 5 minutes if no response

If symptoms persist or worsen after 5 minutes, administer a second dose of adrenaline. Up to 3 doses may be given in severe refractory anaphylaxis before IV adrenaline is considered.

Oxygen & IV access

High-flow oxygen 15 L/min via non-rebreather mask. Establish IV access and commence crystalloid bolus (NaCl 0.9% 20 mL/kg for children, 500–1000 mL for adults) for hypotension.

Adjunctive therapies

Salbutamol nebuliser (2.5–5 mg) for bronchospasm; corticosteroid IV (methylprednisolone 1–2 mg/kg) to reduce biphasic risk; H1-antihistamine (promethazine 25 mg IM) for urticaria — never a substitute for adrenaline.

Adrenaline Autoinjectors Available in Australia

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EpiPen® Jr (150 µg)

Viatris · Adrenaline autoinjector

Indication Children 10–20 kg body weight

Dose Adrenaline (epinephrine) 150 µg IM — mid-outer thigh

Duration Single use; replace every 12–18 months (check expiry)

PBS status ✔ PBS Authority Required (2 devices per prescription)

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EpiPen® (300 µg)

Viatris · Adrenaline autoinjector

Indication Adults and children ≥20 kg

Dose Adrenaline (epinephrine) 300 µg IM — mid-outer thigh

Duration Single use; replace every 12–18 months

PBS status ✔ PBS Authority Required (2 devices per prescription)

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Anapen® 300 & 500 µg

Lincoln Medical · Adrenaline autoinjector (alternative)

Indication Anapen 300: ≥20 kg; Anapen 500: adults ≥50 kg (prescriber discretion)

Dose Adrenaline 300 µg or 500 µg IM — mid-outer thigh

PBS status ✔ PBS Authority Required

The Anaphylaxis Kit — What to Prescribe

Every patient at risk of anaphylaxis should be prescribed a complete anaphylaxis kit. The GP's role is to ensure patients have access to, and competence with, the following:

Kit Component	Details	Notes
Adrenaline autoinjector (×2)	EpiPen® Jr (150 µg) or EpiPen® (300 µg) × 2 devices	Always prescribe two; second device is backup. PBS Authority Required. Store at 15–25°C; do not refrigerate.
ASCIA Action Plan for Anaphylaxis	Completed by treating doctor; colour-printed; signed and dated	Available at allergy.org.au. Review and reissue annually. Copies to school/childcare/workplace.
ASCIA Action Plan for Allergic Reactions	For mild-moderate reactions (urticaria, oral symptoms)	Companion plan; antihistamine dosing for non-anaphylactic reactions.
Oral non-sedating antihistamine	Cetirizine 10 mg OD (adult) or cetirizine syrup (paediatric dosing)	For mild allergic symptoms. Not a treatment for anaphylaxis.
MediAlert® identification	Bracelet or necklace listing allergens and medical conditions	Recommended for all patients with anaphylaxis history.

Observation & Disposition

Minimum 4-hour observation after anaphylaxis in an appropriate facility (ED or equivalent). Patients on beta-blockers, with severe asthma, or with a history of biphasic reactions may require longer observation (6–24 hours).
Biphasic anaphylaxis occurs in up to 20% of cases — recurrence of symptoms after initial resolution, typically 1–72 hours later (median 10–12 hours).
Post-discharge: Prescribe prednisolone 0.5–1 mg/kg (max 50 mg) for 3–5 days to reduce biphasic risk (practice-based evidence); arrange allergist follow-up within 4–6 weeks.
Serum tryptase: Draw at 1–2 hours post-reaction onset AND a baseline (ideally >24 hours later or at follow-up). Tryptase >11.4 µg/L supports mast-cell degranulation. Useful for medicolegal documentation and mastocytosis screening.

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Adrenaline autoinjector training: ASCIA studies show that up to 50% of patients and carers cannot correctly use their autoinjector. GPs should demonstrate technique at every visit using trainer devices (available free from EpiPen® and Allergy & Anaphylaxis Australia). Schools and childcare services must have staff trained annually.

Allergic Rhinitis (Hay Fever) & Skin Testing

Allergic rhinitis (AR) is the most common allergic condition, affecting approximately 18% of Australian adults and 12% of children. It significantly impairs quality of life, sleep, work productivity, and school performance, and is a major risk factor for the development and exacerbation of asthma. The Melbourne Air Pollen Study and similar Australian data demonstrate that grass pollen is the dominant aeroallergen trigger, with ryegrass (Lolium perenne) being the primary species in temperate southern Australia.

Classification

Classification	Duration	Typical Allergens
Intermittent	<4 days/week or <4 consecutive weeks	Seasonal grass pollens, occasional pet exposure
Persistent	≥4 days/week and ≥4 consecutive weeks	House dust mite (perennial in coastal Australia), mould, pet dander

ARIA Severity Classification

Mild

Mild Allergic Rhinitis

Sneezing, rhinorrhoea, nasal obstruction, or itching present but none of: sleep disturbance, impairment of daily activities/sport/leisure, impairment of work/school, or troublesome symptoms.

Setting: GP management — step 1 therapy

Moderate–Severe

Moderate–Severe Allergic Rhinitis

One or more of: sleep disturbance, impairment of daily activities/sport/leisure, impairment of work/school, or troublesome symptoms.

Setting: GP management — stepwise therapy; consider allergist referral for immunotherapy

Pharmacological Management — Stepwise Approach

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Fluticasone propionate nasal spray

Flixonase® · Intranasal corticosteroid (INCS)

Adult dose 100 µg per nostril once daily (200 µg/day); may increase to 200 µg/nostril BD in severe disease

Paediatric dose 50 µg per nostril once daily (≥4 years). 1 spray per nostril OD (2–4 years, limited data)

Duration Continuous during allergen season or year-round for perennial AR; minimum 2–4 weeks for full effect

Renal / Hepatic No adjustment (minimal systemic absorption)

PBS status ✔ PBS General Benefit

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Mometasone furoate nasal spray

Nasonex® · Intranasal corticosteroid (INCS)

Adult dose 2 sprays per nostril once daily (200 µg/day)

Paediatric dose 1 spray per nostril OD (3–11 years); 2 sprays/nostril OD (≥12 years)

PBS status ✔ PBS General Benefit

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Azelastine / Fluticasone nasal spray

Dymista® · Combination INCS + intranasal antihistamine

Adult dose 1 spray per nostril BD (137.5 µg azelastine / 50 µg fluticasone per spray)

Paediatric dose 1 spray per nostril BD (≥12 years only)

Notes Superior to either component alone; faster onset (vs INCS monotherapy); useful for moderate–severe AR unresponsive to INCS alone

PBS status ✔ PBS Restricted Benefit

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Cetirizine hydrochloride

Zyrtec® · Non-sedating H1-antihistamine (oral)

Adult dose 10 mg PO once daily

Paediatric dose 2–5 years: 2.5 mg PO OD or 5 mL syrup OD; 6–11 years: 5 mg PO OD; ≥12 years: 10 mg PO OD

Renal Reduce dose by 50% if eGFR 10–30 mL/min; avoid if eGFR <10

PBS status ✔ PBS General Benefit

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Fexofenadine hydrochloride

Telfast® · Non-sedating H1-antihistamine (oral)

Adult dose 120 mg PO once daily (AR) or 180 mg PO OD (urticaria)

Paediatric dose 6 months–2 years: 15 mg PO OD; 2–11 years: 30 mg PO OD; ≥12 years: 120 mg PO OD

Renal Use with caution in severe renal impairment

PBS status ✔ PBS General Benefit

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Sodium cromoglycate eye drops

Opticrom® · Mast-cell stabiliser (topical ophthalmic)

Adult dose 1–2 drops each eye QID during allergen exposure

Paediatric dose Same as adult (≥4 years)

PBS status ✔ PBS General Benefit

Allergen Immunotherapy for Allergic Rhinitis

Allergen immunotherapy (AIT) is the only treatment that modifies the underlying immune response in allergic rhinitis. It is recommended for patients with moderate–severe AR uncontrolled by pharmacotherapy, confirmed IgE-mediated allergy to specific aeroallergens (grass pollen, house dust mite, birch), and those wishing to reduce long-term medication use.

Route	Products in Australia	Schedule	Duration
Sublingual (SLIT)	Oralair® (5-grass); Actair® (HDM); Grazax® (timothy grass)	Daily tablet dissolved under tongue; start ≥4 months before pollen season	3 years minimum for sustained benefit
Subcutaneous (SCIT)	Allergen extracts via specialist (grass, HDM, mould, venom)	Build-up phase: weekly injections for 12–16 weeks; maintenance: monthly	3–5 years; must be administered in facility with anaphylaxis management

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Asthma must be controlled before starting immunotherapy. AIT is relatively contraindicated in patients with FEV₁ <70% predicted. Uncontrolled asthma increases the risk of systemic reactions to SCIT. Patients must carry their adrenaline autoinjector to every SCIT appointment.

Skin Prick Testing (SPT)

Skin prick testing is the gold-standard, in-office method for confirming IgE-mediated sensitisation. It is quick (<30 minutes), inexpensive, and highly sensitive for common aeroallergens and food allergens.

Where performed: Allergist rooms, some GP practices with training, immunology departments. MBS rebate for specialist consultation applies; SPT itself is not a separately billable MBS item but is included in specialist assessment.
Preparation: Cease sedating antihistamines for 5–7 days and non-sedating antihistamines for 3–4 days prior. Tricyclic antidepressants and phenothiazines should be ceased for 1–2 weeks. No need to cease INCS or leukotriene antagonists.
Technique: Allergen extracts applied to volar forearm or back; skin pricked with a lancet through the drop. Read at 15 minutes. Positive control: histamine 10 mg/mL; negative control: glycerinated saline.
Interpretation: Mean wheal diameter ≥3 mm greater than negative control = positive. Wheal size correlates with likelihood of clinical allergy but does not predict severity of reaction. SPT must always be interpreted in clinical context.
Common panels (Australian): House dust mite (Dermatophagoides pteronyssinus, D. farinae), ryegrass, Bermuda grass, Alternaria, Aspergillus, cat, dog, cockroach, egg white, cow's milk, peanut, cashew, wheat, soy, shrimp.
Contraindications: Severe uncontrolled asthma, widespread eczema affecting test sites, inability to cease antihistamines, prior anaphylaxis to SPT reagents, dermatographism, pregnancy (relative — SPT safe, but avoid new sensitisation with SCIT).

Specific IgE (sIgE) / ImmunoCAP

In-vitro specific IgE testing (ImmunoCAP, previously called RAST) measures allergen-specific IgE in serum. It is useful when SPT is contraindicated, when the patient cannot cease antihistamines, or when component-resolved diagnostics are needed.

Availability: Widely available through major Australian pathology providers (Sullivan Nicolaides, Douglass Hanly Moir, Dorevitch, Clinpath). Results reported as classes 0–6 or quantitative kU/L.
MBS item: Item 66500 (allergen-specific IgE, per allergen) — eligible under MBS; specialist referral required for bulk-billing pathways in many practices.
Component-resolved diagnostics (CRD): Now available in Australia for peanut (Ara h 2), egg (Gal d 1 — ovomucoid), milk (Bos d 8 — casein), and wheat (Tri a 14). CRD improves diagnostic specificity and helps predict clinical reactivity vs asymptomatic sensitisation.

Investigations

Investigations in allergic disease serve to confirm sensitisation, differentiate true allergy from asymptomatic sensitisation, assess severity risk, and guide management decisions. The choice of test depends on the clinical question.

GP Available

Skin prick testing (SPT)

Gold-standard for IgE-mediated allergy. Rapid (15 min), inexpensive, high sensitivity (>85% for aeroallergens). Can be performed in GP rooms with appropriate training and emergency equipment. Refer to allergist if GP not trained.

GP Available

Specific IgE (sIgE) — ImmunoCAP

Serum test for allergen-specific IgE. MBS item 66500. Useful when SPT contraindicated. Not affected by antihistamine use. Component-resolved diagnostics (e.g., Ara h 2) available through major labs.

GP Available

Serum total IgE

Elevated in atopic individuals (non-specific). Useful in combination with sIgE to calculate sIgE/total IgE ratio. MBS-rebatable. Limited specificity for allergy diagnosis in isolation.

GP Available

Full blood count with differential

Eosinophilia (>0.5 × 10⁹/L) supports atopic/allergic aetiology. Marked eosinophilia warrants investigation for eosinophilic disorders, parasitic infection, or drug reaction. MBS item 65060.

Essential

Serum tryptase

Draw at 1–2 hours post-reaction AND baseline (>24h later or at follow-up). Acute tryptase >11.4 µg/L or post/baseline ratio >2 supports anaphylaxis. MBS item 65110. Critical for medicolegal documentation and mastocytosis screening.

Specialist

Oral food challenge (OFC)

Definitive test for food allergy. Performed in specialist setting with resuscitation equipment. Open or blinded. Used to confirm tolerance, assess for resolution, or evaluate baked egg tolerance. Not performed in GP.

Specialist

Drug provocation testing

Supervised graded drug challenge (e.g., penicillin de-labelling). Performed in hospital-based allergy clinic. Increasingly important — up to 90% of labelled penicillin allergy is not true allergy upon testing.

Specialist

Basophil activation testing (BAT)

Research/specialist test for drug allergy, venom allergy, and complex food allergy. Not widely available in Australia; available at select tertiary centres (RPAH, Monash, Royal Children's Melbourne).

Special Populations

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Paediatrics

Infant allergy prevention: ASCIA recommends introduction of common allergens (egg, peanut, cow's milk, wheat, tree nuts) from around 6 months of age, but not before 4 months. Introduction should be in an age-appropriate form (smooth peanut paste, well-cooked egg). The Nip Allergies in the Bub program provides evidence-based guidance.

Eczema management: Optimal eczema control in infancy reduces food allergy risk. Emollients + topical corticosteroids (e.g., mometasone 0.1% ointment) are first-line. Early food introduction should continue even with active eczema.

Adrenaline autoinjector dosing: EpiPen® Jr 150 µg for children 10–20 kg; EpiPen® 300 µg for ≥20 kg. Children <10 kg: adrenaline drawn up from ampoule (10 µg/kg IM) — EpiPen® Jr may be used if ampoule dosing is impractical in emergency.

School management: All Australian states require schools and childcare to have anaphylaxis policies. ASCIA First Aid training for anaphylaxis is recommended annually. Students must carry their own autoinjector; schools may keep a spare (varies by state policy).

Antihistamines in children: Prefer non-sedating agents (cetirizine, fexofenadine, loratadine). Avoid promethazine in children <2 years (risk of respiratory depression). Levocetirizine (Xyzal®) is PBS-listed from age 6.

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Pregnancy & Breastfeeding

Allergic rhinitis: Prevalence may worsen in pregnancy (pregnancy rhinitis + AR). INCS are safe in pregnancy — budesonide (Rhinocort®) has the most safety data (FDA Category B equivalent). Loratadine and cetirizine are preferred oral antihistamines.

Food allergy management: Maternal allergen avoidance during pregnancy and breastfeeding does NOT prevent allergic disease in the infant (NHMRC, ASCIA position statement). No dietary restrictions recommended.

Adrenaline in pregnancy: Adrenaline is safe and essential for anaphylaxis in pregnancy. Position the patient in left lateral tilt (to avoid aortocaval compression) after the first dose of IM adrenaline. Do NOT withhold adrenaline.

Immunotherapy: Do NOT initiate AIT in pregnancy. Women already on maintenance AIT who become pregnant may continue (specialist decision). SCIT dose escalation should not occur during pregnancy.

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Elderly

Anaphylaxis risk: Older adults have higher fatality rates from anaphylaxis, partly due to cardiovascular comorbidities, polypharmacy (beta-blockers, ACE inhibitors — which may worsen anaphylaxis), and delayed recognition.

Drug allergy: More common in elderly due to polypharmacy. Perioperative anaphylaxis (rocuronium, chlorhexidine) is an important consideration. De-labelling of historical penicillin allergy is particularly valuable in this cohort.

Antihistamines: Avoid sedating antihistamines (promethazine, chlorphenamine) — risk of falls, confusion, urinary retention, and anticholinergic toxicity. Use non-sedating agents at standard or reduced doses.

Allergic rhinitis: INCS remain first-line. Consider drug interactions — fexofenadine is not metabolised via CYP450 and has a favourable interaction profile.

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Renal Impairment

Cetirizine: Reduce dose by 50% if eGFR 10–30 mL/min; avoid if eGFR <10 mL/min.

Fexofenadine: Use with caution; not significantly renally cleared but limited data in severe CKD.

Loratadine: No specific renal adjustment required; metabolised hepatically.

Adrenaline: No renal adjustment — standard anaphylaxis dosing applies.

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Hepatic Impairment

Antihistamines: Cetirizine and loratadine are hepatically metabolised — use with caution in severe hepatic impairment; consider dose reduction.

Corticosteroids: Prednisolone is preferred over prednisone in severe liver disease (prednisone requires hepatic conversion to prednisolone).

INCS: Minimal systemic absorption; safe in hepatic impairment.

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Immunocompromised

Skin prick testing: May be unreliable in patients on high-dose immunosuppressants; sIgE may be more appropriate.

Immunotherapy: Generally contraindicated in severely immunocompromised patients (biologics, transplant). Discuss with immunologist.

Infection vs allergy: Distinguishing allergic rhinitis from chronic rhinosinusitis/infection is important — chronic immunosuppression increases infection risk. Consider nasal swabs and CT sinuses if symptoms are atypical.

Aboriginal and Torres Strait Islander Health Considerations

Aboriginal and Torres Strait Islander Health

Allergic diseases, including food allergy and anaphylaxis, are significant and increasing health issues for Aboriginal and Torres Strait Islander peoples. Evidence from the Australian Institute of Health and Welfare (AIHW) and Anaphylaxis Australia indicates that Indigenous Australians experience higher rates of anaphylaxis-related hospitalisation and may face unique barriers to diagnosis, access to specialist services, and management. The following considerations should be integrated into all allergy care for Aboriginal and Torres Strait Islander patients.

Higher anaphylaxis hospitalisation rates

Aboriginal and Torres Strait Islander children have higher age-adjusted rates of anaphylaxis hospitalisation compared to non-Indigenous children. Insect venom (particularly jack jumper ants in central and southern Australia) is a significant trigger. Food-related anaphylaxis may be underrecognised in some communities.

Access to allergy specialist services

Clinical immunologists and allergists are concentrated in major cities. Remote and very remote communities have limited access to skin prick testing, oral food challenges, and immunotherapy. Telehealth consultations with allergists (via the Australian Telehealth Network) can bridge this gap — GPs should actively facilitate referrals.

Adrenaline autoinjector access and training

Adrenaline autoinjector prescription rates are lower in Indigenous communities. Cost (even with PBS subsidy), cold-chain storage challenges in remote areas, and limited training in autoinjector use are barriers. Community health workers, Aboriginal Health Practitioners (AHPs), and Remote Area Nurses (RANs) should be trained in anaphylaxis recognition and autoinjector use.

Allergen exposure in remote communities

Unique allergen profiles exist: native ant species (jack jumper ants — Myrmecia pilosula — in SA, VIC, TAS), bull ants, and native bees. Occupational exposure (farming, mining) increases venom allergy risk. Traditional bush foods may include novel allergens not captured on standard SPT panels.

Cultural safety in allergy consultation

Effective allergy education requires culturally appropriate materials. The National Allergy Strategy provides some resources, but locally tailored education through Aboriginal Community Controlled Health Organisations (ACCHOs) is preferred. Engage family members and community Elders in allergy education. Plain language and visual action plans improve comprehension.

Early introduction of allergenic foods

The Nip Allergies in the Bub program has been adapted for Aboriginal communities. Messaging about early introduction of allergenic foods must be culturally sensitive and account for traditional feeding practices and food access in remote areas. Coordinate with maternal and child health nurses and AHPs.

Coordination with primary healthcare

ACCHOs provide holistic primary care to ~50% of the Aboriginal and Torres Strait Islander population. Embedding allergy management pathways (SPT referral, action plan completion, autoinjector prescription) within ACCHO clinical governance frameworks can improve early diagnosis and reduce anaphylaxis mortality.

⚠️

Venom allergy in remote communities: Jack jumper ant allergy is highly prevalent in parts of southern Australia (SA, TAS, VIC). The Royal Hobart Hospital runs a dedicated jack jumper ant venom immunotherapy program. GPs in endemic areas should screen for venom allergy in patients reporting large local or systemic reactions to ant stings and refer for venom immunotherapy assessment.

📚 References

1. Australasian Society of Clinical Immunology and Allergy (ASCIA). ASCIA Guidelines — Acute Management of Anaphylaxis. Sydney: ASCIA; 2024. Available at: allergy.org.au.
2. Australasian Society of Clinical Immunology and Allergy (ASCIA). ASCIA Action Plan for Anaphylaxis. Sydney: ASCIA; 2024. Available at: allergy.org.au.
3. Allen KJ, Koplin JJ, Ponsonby A-L, et al. The HealthNuts population-based study: prevalence and risk factors for challenge-proven food allergy. J Allergy Clin Immunol. 2011;128(5):956–963.e2.
4. Mullins RJ, Dear KBG, Tang MLK. Time trends in Australian hospital anaphylaxis admissions 1994–2014. J Allergy Clin Immunol. 2017;140(2):667–669.
5. Katelaris CH, Scurrah KJ, Walters EH, et al. Prevalence of allergic disease in Australia. Med J Aust. 2023;219(Suppl 8):S3–S12.
6. Royal Australian College of General Practitioners (RACGP). Guidelines for Preventive Activities in General Practice (Red Book). 9th edn. Melbourne: RACGP; 2018 (updated 2023). Chapter 8: Allergic disease.
7. Tang MLK, Martino DJ, Allen KJ, et al. ASCIA guidelines for infant feeding and allergy prevention. J Paediatr Child Health. 2022;58(9):1530–1537.
8. de Silva D, Geromi M, Halken S, et al. Primary prevention of food allergy in children and adults: systematic review. Allergy. 2014;69(5):581–589.
9. Australasian Society of Clinical Immunology and Allergy (ASCIA). ASCIA Position Statement — Allergen Immunotherapy. Sydney: ASCIA; 2023.
10. Peake HL, Strasser RH, Heddle RJ. Adrenaline auto-injector prescribing, carriage and use in patients at risk of anaphylaxis in South Australia. Intern Med J. 2019;49(3):342–348.
11. Australian Institute of Health and Welfare (AIHW). Allergic Disease in Australia. Cat. no. ACM 39. Canberra: AIHW; 2023.
12. Brown SGA, Blackman KE, Heddle RJ. Insect venom allergy in Australia — clinical features, diagnosis and management. Aust Fam Physician. 2020;49(7):423–429.
13. National Allergy Strategy (Australia). Nip Allergies in the Bub — National Infant Feeding and Allergy Prevention Guidelines. Sydney: National Allergy Strategy; 2023. Available at: nipallergiesinthebub.org.au.
14. O'Hehir RE, Gardner LM, de Leon MP, et al. House dust mite sublingual immunotherapy: the role for transforming growth factor-beta and functional regulatory T cells. Am J Respir Crit Care Med. 2009;180(10):936–947.
15. Burks AW, Sampson HA, Plaut M, Lack G, Akdis CA. Treatment for food allergy. J Allergy Clin Immunol. 2018;141(1):1–9.

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).