[Clinical and microbiological study of otitis media in infants]

The objective of this study was to determine the prevalence of bacteria isolated from middle ear effusions in infants with otitis media in our environment. Data collected from 50 patients of the Infant Section of the Unidad Integrada Hospital Clínico-San Juan de Dios were evaluated prospectively from October 1, 1992 to March 7, 1994. Patients between 1 month and 1 year of age, with unilateral or bilateral otitis media diagnosed by otoscopy criteria and positive myringotomy, were recruited for study. Those who had received any antibiotic during the previous 3 days or had been admitted to the hospital more than 5 days before were excluded. We found that failure to thrive (18%) is a common form of onset of otitis media in children under one year of age. Rhinorrhea and nasal obstruction (60%), cough (50%) and fever (46%) were the most frequent symptoms at the moment of diagnosis. Blood analysis does not add any information for diagnosing otitis media. The difference between acute otitis media and otitis media with effusion is likely to be more clinical rather than microbiological. The recovery of pathogens from 62% of the ear cultures correlates with the figures reported in the literature. The predominance of S. pneumoniae (38%), followed by H. influenzae (25%), is in agreement with previous findings internationally. In our study, there is no evidence of viruses alone causing otitis media in infants. Consequently, antibiotic therapy should be indicated in every child with otitis media.