Epidemiology and prophylaxis of rheumatic fever in Delhi--a five year follow-up. Three- versus four-week administration of benzathine penicillin G: effects on incidence of streptococcal infections and recurrences of rheumatic fever. Prophylaxis of recurrences of rheumatic fever with penicillin given orally; final report of a five year study. Rheumatic fever prophylaxis using benzathine penicillin G (BPG): two- week versus four-week regimens: comparison of two brands of BPG. Discontinuation of antistreptococcal prophylaxis. A double-blind study in rheumatic patients free of heart disease. Prophylaxis of recurrent rheumatic fever. Therapeutic-continuous oral penicillin vs monthly injections.
nan To investigate the effects of 3-week versus 4-week administration of benzathine penicillin G (BPG) on the incidence of Group A streptococcal infections and the recurrences of rheumatic fever (RF).
                We started, in 1979, randomly allocating all patients with RF to a 3-week or 4-week BPG prophylaxis program. They were examined at the RF clinic, every 3 to 6 months, and at any time they did not feel well. During 1979 to 1989, throat cultures and sera for antistreptolysin O and streptozyme titers were obtained at each clinic visit. Chest radiographs, electrocardiogram, color Doppler echocardiograms, and acute phase reactants were obtained.
                Two hundred forty-nine patients fulfilled the revised Jones criteria and were followed until December 1991: 124 in the 3-week and 125 in the 4-week program. Their age, sex, weight, percentage with history of RF, severity of cardiac involvement, follow-up duration, and compliance to program were comparable. Eight hundred eighty throat cultures were collected in the 3-week program and 770 were collected in the 4-week program. Six hundred sixteen and 627 sera were determined in each program for antistreptolysin O, and 582 and 592 sera for streptozyme titers.
                True streptococcal infections occurred in both programs: 39 infections in the 3-week program, and 59 infections in the 4-week program (7.5 vs 12.7 per 100 patient-years). Four infections with no antibody response occurred in the 3-week program, and three such infections in the 4-week program. Nine RF recurrences occurred in 8 patients in the 3-week program, and 16 recurrences in 16 patients in the 4-week program. Prophylaxis failure occurred in 2 of 124 patients in the 3-week program, and in 10 of 125 patients in the 4-week program (0.25 vs 1.29 per 100 patient-years). The overall recurrences/infections rate in each program was comparable, 13.6% vs 15.5%, but the recurrences/ infections rate due to prophylaxis failure was higher in the 4-week program than in the 3-week program, 3.0% versus 9.7%.
                This 12-year prospective and controlled study documented that streptococcal infections and RF recurrences occurred more often in the 4-week program than in the 3-week program. The risk of prophylaxis failure was fivefold greater in the 4-week program than in the 3-week program. nan This prospective study was aimed at answering two important questions: 1) Is a biweekly schedule of 1.2 million U intramuscular benzathine penicillin G (BPG) superior to a 4-week one in the prevention of upper respiratory Group A beta-hemolytic streptococcal (GABHS) infections and rheumatic fever (RF) recurrences? 2) Is there a difference in the bioavailability of BPG obtained from different manufacturers?
                Three hundred sixty rheumatic patients aged 4 to 20 years were randomly assigned to either a biweekly (190 patients) or 4-week (160 patients) BPG prophylactic schedule and were followed-up monthly for 2 years by clinical examination, throat swab culture for GABHS and measurement of antistreptolysin O titer to detect GABHS infection and/or recurrences of RF (according to revised Jones' Criteria). Thereafter, 34 rheumatic subjects, aged 8 to 16 years were randomly assigned to receive a 4-week injection of 1.2 million U of either a locally manufactured BPG brand (22 patients) or an imported one (12 patients). Sera of all patients were tested for penicillin level by plate diffusion method on days 1, 2, 3, 4, 5, 6, 7, 14, 21, and 28 after the intramuscular injection of BPG.
                The GABHS infection rate was found to be 0.2% and 0.3% for patients on the biweekly and 4-week BPG schedules, respectively, with no significant differences between them. However, the RF recurrence rate/patient/year for the 4-week schedule patients (0.12) was double that for the biweekly schedule ones (0.06). Estimation of the bioavailability of the two different brands of BPG demonstrated a difference in their pharmacokinetics and a decrease in the serum penicillin concentration below the minimum inhibitory concentration 3 weeks after the injection of either brand.
                Although a biweekly schedule may not be superior in preventing upper respiratory GABHS infection, it may play a role in preventing the sequelae of such infections. The short duration of penicillinemia explains the superiority of the 2-week schedule in RF prophylais. The difference in the pharmacokinetics of penicillin brands might contribute to the high recurrence rate of RF reported in Egypt. nan nan
Intramuscular penicillin seemed to be more effective than oral penicillin in preventing rheumatic fever recurrence and streptococcal throat infections. Two-weekly or 3-weekly injections appeared to be more effective than 4-weekly injections. However, the evidence is based on poor quality of trials.