急性化脓性中耳炎课件_1.pptVIP

Acute suppurative Otitis Media First Affiliated Hospital of Chongqing Medical University Yu Lin Acute suppurative otitis media (ASOM) is inflammation of the middle ear cleft due to bacterial infection. It is also referred to as acute otitis media . ASOM is most common in children between the ages of 3 to 7 years. Such infants have a short, wide, more horizonally placed eustachian tube than adults, allowing contamination from the regurgitation of feed. Poor sanitation, over-crowding and malnutrition are all risk factors in children. Risk factors in all age groups include recurrent or chronic rhinosinusitis, chest disease and eustachian tube dysfunction . ASOM is a bacterial disease caused by pus forming organisms. Pathogenic bacteria have been isolated from the nasopharynx in up to 97% of children with ASOM. The bacterial infection may be a primary infection, or secondary following a viral acute non-suppurative otitis media. Bacteria enter the middle ear cleft via the eustachian tube, a tympanic membrane perforation or are blood-borne. Common organisms include: Beta haemolytic streptococcus (40%) Haemophilus influenzae (30%) Moraxella catarrhalis (10%) organisms mucous membrane inflammation suppurative stage catarrhal stage infection resolves rupture of tympanic infection resolves chronicity Sources of infection in otitis mediathe Eustachian tube is the chief routea. upper respiratory tract infection frequently a complication of viral infection common cold, acute rhinitis ,acute tonsillitis acute adenoiditis b. acute infection measles, scarlet fever or influenza c. swimming and diving d. anatomical factors the Eustachian tube is shorter , wider and more horizontal in child the external auditory meatus