Antibiotic choice in acute and complicated sinusitis.

The microbiology of 87 patients admitted to hospital, over a five-year period, with acute sinusitis was retrospectively analysed. Sixty-three patients had one or more of an orbital, intracranial, soft tissue or bony complication. Eighty-four patients had maxillary sinus washouts, while 48 required a surgical procedure to their sinuses, and 33, drainage of an empyema. Streptococcus milleri and Haemophilus influenzae were the commonest organisms isolated from sinus aspirates (44 per cent), with a noticeable absence of Streptococcus pneumoniae (10 per cent). Organisms cultured from intracranial, soft tissue or orbitral empyemas were predominantly Streptococcus milleri (50 per cent) and Staphylococcus aureus (25 per cent) with an absence of Haemophilus influenzae (four per cent) and Streptococcus pneumoniae (four per cent). Ampicillin is an appropriate first line antimicrobial agent in patients with acute complicated sinusitis with the addition of cloxacillin in cases with an empyema. Chloramphenicol or ceftriaxone is used in cases with an intracranial complication.