Otitis media

Otitis media(OM)

Acute suppurative otitis media(ASOM)
Def : it is an acute inflammatory reaction of mucosal lining of middle ear cleft the type of this reaction and its progress to become non-suppurative depend on :
? Virulence of M.O invading the cleft.
? Resistance of patients, age of patients.
? Drainage mechanism of cleft, pneumatization .
? AB therapy.
Aetiology
1.rhinosinusitis .
2.nasophyrngitis.
3.tonsillitis.
4.influenza and acute infectious diseases.
5.nasopharyngeal tumor.
6.traumatic perforation of TM.
7.operation on nose & throat.
Bacteriology
1.haemolytic streptococcus.
2.stre. pneumoniea.
3.staph. aureous.
4.H. influenzae.

Histopathology
The accepted sequel of events in ASOM is the deposit of causal MO at the nasopharyngeal end of Eustachian tube followed by spread of inflammation throughout the cleft , the progress sometime vary rapid so need only one night from the onset till perforation of TM and pus discharge.
The 1st effect of tubal infection is the inflammation and occlusion of the tube, air in the middle ear absorbed and not replaced so exudation lead to collection of fluid(effusion) and that is good culture for growth of M.O =lead to suppuration then resolution with or without perforation of TM.