OBJECTIVE : The recurrence of rheumatic fever and rheumatic heart disease (RHD) are still big problem nowadays. These recurrences could be prevented by injection of benzathine penicillin G as secondary prophylaxis. The problem is that most of the health centers have different timing of injection given namely every three or four weeks. The aim of this study to assess proportion difference of benzathine penicillin G (BPG) serum level which beyond the minimum concentration by the end of the third and fourth week post injection of benzathine penicillin G among the rheumatic fever or rheumatic heart disease patients as well as factors that affect the BPG serum level.
METHOD : The study conducted clinical trial towards the rheumatic fever or rheumatic heart disease patients of Cardiology Division, Department of Child Health, Mohammad Hoesin Hospital, from August to November 2017. The BPG serum levels were measured by using HPLC method at the end of the third and fourth weeks post injection of benzathine penicillin G. Statistical analysis with Spearman and Pearson Correlation, Mann Whitney U test were used.
RESULT : 49 researched subjects were involved with age in average around 11.79 years old. The mean level of benzathine penicillin G serum at the end of the third and fourth week was 8.51 (SD 3.26) ?g/ml and 6.64 (SD 3.26) ?g/ml. There was a significant relationship between duration of therapy, age, and level severity of the disease with BPG serum level at the fourth-week post injection. On the other hand, gender and nutritional status have no significant relationship towards BPG serum level at the fourth-week post injection.
CONCLUSION : The proportion of BPG serum level which beyond the minimum concentration at the end of the third-week post injection had lower concentration compared to at the fourth-week post injection. It was recommended to use the fourth week interval for secondary prophylaxis. The main factor that affects the BPG serum level was duration of therapy.