WASHINGTON — Metronidazole is effective in the treatment of non-β-hemolytic streptococcal tonsillitis, Itzhak Brook, M.D., reported in a poster presentation at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.
Although group A β-hemolytic streptococcus (GABHS) is one of the major causes of tonsillitis, other aerobic as well as anaerobic organisms have been isolated from both normal and inflamed tonsils. Some of these organisms are believed to be part of the normal flora, said Dr. Brook, professor of pediatrics at Georgetown University, Washington.
The option of using metronidazole (250 mg every 12 hours for 10 days) was offered to 40 children (mean age 9 years) who presented with sore throat and massive tonsillar enlargement plus at least one of the following: anterior cervical adenitis, temperature higher than 38.3° C, and pharyngeal or tonsillar exudates or pharyngeal injection.
Rapid streptococcal antigen tests were negative in all the patients, and cultures of the tonsils showed no growth of β-hemolytic streptococci, including group A. None of the children had Epstein-Barr antibodies on immunofluorescence.
The 20 who chose metronidazole were similar to the 20 who did not with respect to age, race, sex, family size, current clinical findings, and previous antibiotic use.
Compared with the children who remained untreated, those given metronidazole had significantly lower rates of fevers over 38° C after 1 day (11 vs. 17 children) and after 2 days (3 vs. 9 children), fewer sore throats after 1 day (12 vs. 19) and 2 days (9 vs. 16), and lower rates of tonsillar enlargement after 3 days (11 vs. 16) and 5 days (8 vs. 14). Pharyngeal injection at 2 days also was reduced with metronidazole, Dr. Brook reported at the conference, sponsored by the American Society for Microbiology.
One patient who received metronidazole complained of metallic taste, and three had dark urine.
Metronidazole was chosen for this study because it is effective against anaerobic bacteria, which are thought cause inflammation in the tonsils, but has virtually no activity against facultative and aerobic bacteria.