Definition: ASOM is an acute inflammation of the mucosal lining of the middle ear cleft (middle ear, Eustachian tube and mastoid air cells).
Route of infection:
1.Via the Eustachian tube from:
- The nose: (Sinusitis, acute rhinitis).
- The nasopharynx (Adenoiditis, nasal pack, vomitus, milk regurge).
- The Oropharynx (Tonsillitis, Pharyngitis).
2. Through a drum perforation (swimming and bathing).
Causative organisms:
1. Bacterial:
- Beta haemolytic streptococcus.
- Staphylococcus aureus.
- Streptococcus pneumoniae.
- Haemophilus influenzae.
2. Viral:
Viruses play a role paving the way for pyococcal invasion e.g influenza and exanthema.
Stages of ASOM (Pathology)
- Stage of Eustachian tube obstruction (Tubal catarrh): Oedema and congestion obstructing the Eustachian tube. Air gets absorbed from the middle ear with failure of Eustachian tube opening to equalize the negative pressure.
- Stage of acute catarrhal otitis media: congestion and oedema of the middle ear mucosa with serous exudation.
- Stage of suppuration: The exudate becomes mucopurulent and pus accumulates under tension.
- Stage of perforation: Necrosis of the drum causes perforation.
Incidence: more in infant & children.
Clinical picture of Acute Suppurative Otitis media:
1- Stage of eustachian tube obstruction (tubal catarrh)
Pathology: Tubal obstruction due to congestion, then air is absorbed.
Signs:
- Retracted Tympanic membrane (T.M).
- Prominent lat. process of malleus.
- Exaggerated malleolar folds.
- Shortened handle of malleus.
- Distorted cone of light.
- Limited mobility by siegle.
- Conductive deafness
2- Stage of hyperaemia & congestion : (catarrhal O.M)
Pathology: Oedema & congestion of ME & serous exudate.
Symptoms:
- Starting general symptoms.
- Deafness, tinnitus, pain.
Signs:
- T.M is congested with prominent vascularity, lost cone of light.
- Conductive deafness.
3. Stage of suppuration:
Pathology: Pus accumulates under tension.
Symptoms:
- More severe general symptoms.
- Deafness increase.
- Tinnitus increase.
- Pain: severe, throbbing.
Signs:
- T.M is congested markedly & bulging with lost cone of light.
- Conductive deafness.
4- Stage of perforation
Pathology: Necrosis of part of T.M.
Symptoms:
- General symptoms start to subside.
- Aural discharge.
- Deafness.
- Pain starts to subside.
Signs:
- Mucopurulent, bloody, pulsating discharge.
- Perforated T.M: usually anteroinferior, if large ME mucosa appears congested.
- Conductive deafness.
Investigations:
- Culture and sensitivity.
- Hearing tests: Conductive deafness.
Treatment of Acute Suppurative Otitis media
I- Before perforation treatment:
a- Medical:
- Rest, light diet, fluids.
- Systemic antibiotics, for 10 days.
- Analgesics.
- Nasal decongestants.
- local antibiotic drops or warm glycerin phenol to decrease edema &pain.
b- Surgical: myringotomy
Indications of myringotomy:
- Failed medical ttt for 48 hours.
- Bulging T.M (pus under tension).
- Complications. -Immunosuppressed patients,for fear of complications.
- Infants and children (don’t wait for bulging to occur).
After myringotomy, Doctor should give:
- Antibiotics according to Culture and sensitivity.
- Local ear drops.
- Avoid water entry.
- Aural toilet.
II- After perforation treatment:
a- Medical:
As done "after myringotomy".
b- Surgical:
Myringotomy if perforation is small or high.
Prognosis of ASOM:
- Cure: middle ear mucosa & hearing return normal.
- Chronicity: suppurative or non suppurative.
- Complications.