Bacterial etiology of conjunctivitis-otitis media syndrome.

Simultaneous cultures of conjunctivae and middle ear exudates were obtained from 20 episodes of the syndrome of purulent conjunctivitis and otitis media. Paired cultures from 18 episodes yielded Haemophilus influenzae at both sites. In two cases with prior topical antibacterial therapy of the conjunctivitis, H influenzae was isolated from the middle ear exudate only. Biotyping and outer membrane protein analysis of H influenzae isolates from five patients demonstrated that: conjunctival and middle ear strains were concordant in all cases, and all five patients had different strains. The conjunctivitis-otitis media syndrome is most often caused by strains of nontypable H influenzae of diverse clonotype.