Long-term Efficacy of 2 Year WHO Multiple Drug Therapy (MDT) in Multibacillary (MB) Leprosy Patients

Abstract

Relapse rate estimates after 2 year WHO multiple drug therapy (MDT) in multi-bacillary (MB) leprosy vary. Between 1987 and 1994, 500 MB leprosy patients completing 2 year MDT were enrolled in a prospective relapse study. The majority of patients (N = 316) were treated and followed at the physician-staffed Cebu Skin Clinic (CSC), whereas others (N = 184) received therapy from government clinics and were followed by CSC technicians in the field. Relapse definition was an increased bacteriologic index (BI) and new skin lesions, supplemented with mouse footpad inoculations. Through 2002, follow-up was 5368 person-years, with a mean of 10.8 years per patient. The absolute relapse rate was 3% (15/498; 0.28/100 person-years), with a cumulative risk estimate of 3.9% at 15 yrs. For a subset of 217 patients followed for >or=12 yrs or until relapse, relapses occurred in 9% (13/142) attending the CSC, versus 3% (2/75) assessed in the field (p = 0.09). The rate for patients followed at CSC for >or=12 yrs and a pre-treatment BI >or=2.7+ was 13% (13/98). All relapses were BL or LL, with pre-treatment BI's of >or=2.7+. Relapses occurred long after completion of therapy, between 3 and 11 yrs from the midpoint of the examination without relapse to detection, or between 6 to 13 yrs to the actual year of detection, 7 occurring at >or=10 yrs. Lesion material from all relapses contained M. leprae that was rifampin and clofazimine sensitive, whereas 3 showed partial or full dapsone resistance. [Follow-up rigor and time], medical expertise, and pre-treatment bacterial load influence relapse rates after 2 yr MDT.

Fatores associados à recidiva em hanseníase em Mato Grosso

“…This can be explained by disease severity possibly associated with bacterial persistence and specifi c immune response. 4,8,9,16 MB cases treated with 24 doses have higher risk of relapse and are associated with borderline-lepromatous and lepromatous leprosy and high BI (≥2+) in initial treatment. 4,8 The use of alternative drugs to replace the standard regimen for leprosy treatment should be considered.…”

“…4,8,9,16 MB cases treated with 24 doses have higher risk of relapse and are associated with borderline-lepromatous and lepromatous leprosy and high BI (≥2+) in initial treatment. 4,8 The use of alternative drugs to replace the standard regimen for leprosy treatment should be considered. 4,8,18 Antimicrobial combinations seem to be effective but minocycline plus rifampicin only have proven to eliminate all M. leprae; antimicrobial combinations that include rifampin and either ofl oxacin, clarithromycin or minocycline can improve treatment effectiveness.…”

“…4,8 The use of alternative drugs to replace the standard regimen for leprosy treatment should be considered. 4,8,18 Antimicrobial combinations seem to be effective but minocycline plus rifampicin only have proven to eliminate all M. leprae; antimicrobial combinations that include rifampin and either ofl oxacin, clarithromycin or minocycline can improve treatment effectiveness. 4,8,18 However, these more severe cases should receive treatment in specialized centers.…”

“…Relapse rates are between 3% and 17% with 2 to 15 years for relapse. 4,8,9,21 There are major differences in the relapse rates among Brazilian regions such as the Brazilian legal Amazon border. d The state of Mato Grosso, central-western Brazil, accounted for 6% to 20% of relapsed cases between 2004 and 2006.…”

“…6 Studies on factors associated with relapsed leprosy are relatively scant in Brazil and most have focused on clinical/laboratory and treatment factors overlooking socioeconomic aspects and those related to health services. They have pointed out the following determinant factors: household contacts, 10,24 persistence of bacillus (bacterial index [BI] ≥2+), 4,9,10,24 interval between initial treatment and relapse, clinical form of leprosy, duration/type of MDT and drug reaction events. 4,8,10,21,24 The present study aimed to describe factors associated with relapse of leprosy.…”