Traitements antibiotiques des angines. Indications, modalités, durées

[Rapid antigen detection tests for diagnosis of group A streptococcal pharyngitis: comparative evaluation of sensitivity and practicability of 16 in vitro diagnostics medical devices performed in July 2002 by the French health products safety agency (Afssaps) as part of its market control mission]

Within the scope of its health products control mission, the French Health Products Safety Agency (Afssaps) collaborating with two expert's sites, has assessed the 16 tests available on the French market in 2002 for rapid diagnosis of the Streptococcus A tonsillitis. The purpose of this study was to verify the reliability and rapidity of these tests and to give some information to the users about their analytical criteria and practicability characteristics. The analytical study has been performed on a same panel of four reference strains of Streptococcus pyogenes dilutions to determine the limit of detection of all the reagents in the same condition of methodology. The limit of detection has been calculated with the results expressed in colony forming unit by ml (CFU/ml). The practicability study has permitted to analyze the quality of the presentation, the easiness of the final reading and of performing tests. A score has been established for each rapid test. A classification of the analytical sensitivity (limit of detection) and practicability (score) of these 16 devices has been established. The limit of detection of the reagents giving the best results allows the detection of the lowest bacterial concentration of the panel which is 10(5) CFU/ml. Regarding practicability, the results suggest that, the immunochromatographic strip methods have the best score in a view with the use by a non medical laboratory.

[Treatment of acute group A beta-hemolytic streptococcal tonsillitis in children with a 5-day course of josamycin]

MATERIAL AND METHODS

In this randomized open study, 325 children aged two to 15 years with acute tonsillitis and a positive test of GA beta H streptococcal antigen were treated with josamycin 50 mg.kg-1.day-1 b.i.d for 5 days, or penicillin 50,000 to 100,000 IU/day t.i.d for 10 days. Clinical assessments and throat cultures for GA beta HS isolation were performed at the inclusion visit (V1), at the end of treatment visit (V2: day 12 for all patients) and at the follow-up visit (V3: day 30). In case of positive GA beta HS culture, the bacterial DNA by RFLP was performed to differentiate between the persistence (presence of original strain at V2), relapse (eradication at V2 and acquisition of same strain at V3) and reinfection (eradication at V2 and acquisition of different strain at V3).

RESULTS

Two hundred and twenty-three patients were included in the bacteriological and clinical criteria per protocol analysis. At V2, eradication rates were comparable: 82% in josamycin and 80% in penicillin patients; clinical cure rates were 90% and 89%. At V3, relapse of GAS assessed only on clinically and bacteriologically cured patients at V2 occurred in 12% of josamycin patients and 12.8% of penicillin patients. Tolerance was good; 14% and 10% of josamycin and penicillin patients respectively experienced an adverse event.

CONCLUSION

In this non-inferiority study, the efficacy of a 5-day course of josamycin is comparable to reference treatment in GA beta HS tonsillitis in children.