Clinical efficacy and antimicrobial pharmacodynamics

Randomized, comparative efficacy trial of oral penicillin versus cefuroxime for perianal streptococcal dermatitis in children

OBJECTIVE

To investigate the efficacy of penicillin compared with cefuroxime for group A beta-hemolytic Streptococcus pyogenes (GABHS) perianal dermatitis.

STUDY DESIGN

Children 1 to 16 years of age with signs and symptoms of perianal dermatitis and a positive anal swab were randomized to penicillin or cefuroxime treatment and were clinically re-evaluated on day 3 and at the end of treatment (cefuroxime, day 7; penicillin, day 10). An anal swab was obtained to document eradication of GABHS at the end of treatment. Severity of disease was assessed with a clinical score (perianal erythema, 5 points; perianal itch, 3 points; painful defecation, 3 points; constipation, 2 points).

RESULTS

Patients were enrolled and randomly assigned to penicillin (n = 18) or cefuroxime (n = 17) treatment. Treatment with penicillin was inferior to cefuroxime, which led to premature study termination after consultation with the ethics committee. Clinical improvement was more rapid in the cefuroxime group (P = .028) and GAHBS was not isolated from the anus the last day of therapy in 13 of 14 patients treated with cefuroxime compared with 7 of 15 patients treated with penicillin (P < .01).

CONCLUSIONS

Cefuroxime was more effective than penicillin and therefore should be considered as the treatment of choice for perianal dermatitis due to GABHS.

Pharmacokinetics and tissue penetration of linezolid following multiple oral doses

The pharmacokinetics of multiple-dose linezolid were determined following administration of five 600-mg oral doses given every 12 h to each of six healthy male volunteers. Concentrations of the drug were determined in plasma and inflammatory blister fluid using high-pressure liquid chromatography. A mean peak concentration in plasma of 18.3 microg/ml (standard deviation [SD], 6.0) was attained at a mean time of 0.7 h (SD, 0.3) after the final dose. The penetration into the inflammatory fluid was 104% (SD, 20.7). A mean peak concentration of 16.4 microg/ml (SD, 10.6) was attained in the inflammatory fluid at 3 h (SD, 0.6) after the final dose. The elimination half-life from serum and inflammatory fluid was 4.9 (SD, 1.8) and 5.7 (SD, 1.7) h, respectively. The area under the concentration-time curve in plasma and blister fluid was 140.3 (SD, 73.1) and 155.3 (SD, 80.1) microg x h/ml, respectively. These data suggest that linezolid has good tissue penetration, and we can predict that it will be successful in the treatment of a variety of gram-positive infections.