Effect of Lincomycin on Anaerobic Bacterial Infections in Otolaryngological Patients

Abstract

To evaluate the effects of lincomycin on anaerobic bacterial infections, lincomycin hydrochloride was administered to 20 outpatients (12 with acute pharyngitis, 2 with acute sinusitis, 1 with chronic sinusitis, 2 with chronic otitis media, 1 with acute otitis media, 1 with perichondritis auriculae and 1 with peritonsillar abscess).
The patients were given intramuscularly injections of 300-1200mg of lincomycin 1-2 times a day for 1 to 5 days.
Cultures yielded 22 bacterial strains (8 Peptococcus sp., 5 Peptostreptococcus sp., 5 Bacteroides fragilis, 3 Bacteroides melaninogenicus and 1 Fusobacterium sp.).
Minimal inhibitory concentrations (MIC) of lincomycin for anaerobes were determined by the agar dilution method.
Efficacy was determined by clinical improvement and eradication of bacteria at the time the drug was discontinued.
The overall efficacy rate was 73.7%.
Bacteria eradication rates were: Peptococcus sp. 83.3%, Peptostreptococcus sp. 60.0%, B. fragilis 100%, in 1 case both Peptococcus sp. and B, melaninogenicus, and in another both Peptococcus and B. fragilis were eradicated. Lincomycin was ineffective in a case of B. melaninogenicus and one of Fusobacterium sp. infection.
In this trial, the effectiveness of lincomycin against Peptostreptococcus sp. was 60.0% which is rather low compared with its usual high effectiveness against this strain reported elsewhere. This can be attributed to the fact that most of these patients had received other antibiotics possibly including macrolides such as erythromycin and oleandomycin which are known to induce cross resistance to lincomycin in other medical institutions before visiting us, and that may have produced induced resistance.