title: Utility of recombinant proteins LID-1 and PADL in screening for Mycobacterium leprae infection and leprosy.
abstract: BACKGROUND
  Despite the widespread use of multidrug therapy, leprosy remains an important public health concern in many regions. Detection is generally limited to clinical exam.
  
  
  METHODS
  As a two-tiered active case finding strategy, we used the LID-1 (leprosy IDRI diagnostic-1), and PADL (protein advances for the diagnosis of leprosy) antigens for serological examination of 2526 individuals randomly selected from 10 472 residents in a leprosy hyperendemic area (Cajazeiras, Paraiba, Brazil). Almost all seropositive (95%) and a subset of seronegative (17%) subjects then underwent clinical evaluations.
  
  
  RESULTS
  Prevalence of clinically apparent leprosy was 2.3% (19 cases among 834 fully examined individuals). LID-1 and PADL demonstrated a high sensitivity for supporting leprosy diagnosis at 89% and 87%, with positive predictive values (PPV) of 3.5% and 3.7%. The specificity for clinically apparent leprosy was low at 42% and 38%, respectively, and was likely reduced due to the presence of many asymptomatic individuals infected with Mycobacterium leprae.
  
  
  CONCLUSIONS
  Our data indicate the utility of the LID-1 and PADL antigens as primary screening tools for the detection of M. leprae infection and identification of leprosy patients. The follow-up of seropositive subjects could clarify the predictive value and utility of detecting anti-LID-1 and PADL antibodies within leprosy control programs.
authors.affiliation: Federal University of Campina Grande, Cajazeiras, Paraíba, 58429-900, Brazil.
authors.forename: Marilena Maria
authors.initials: MM
authors.lastname: de Souza
authors.affiliation: Laboratório de Pesquisa em Infectologia, Federal University of Bahia, Salvador, Bahia, 40110-010, Brazil enetto@ufba.br.
authors.forename: Eduardo M
authors.initials: EM
authors.lastname: Netto
authors.affiliation: Laboratório de Pesquisa em Infectologia, Federal University of Bahia, Salvador, Bahia, 40110-010, Brazil.
authors.forename: Maria
authors.initials: M
authors.lastname: Nakatani
authors.affiliation: Infectious Disease Research Institute, Seattle, WA, 98102, USA.
authors.forename: Malcolm S
authors.initials: MS
authors.lastname: Duthie
mesh_terms: D000328:Adult; D000907:Antibodies, Bacterial / Q000276:immunology*; D000942:Antigens, Bacterial / Q000276:immunology*; D001938:Brazil / Q000453:epidemiology; D005260:Female; D006801:Humans; D007918:Leprosy / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology*; D008297:Male; D009166:Mycobacterium leprae / Q000276:immunology; D015995:Prevalence; D011994:Recombinant Proteins / Q000276:immunology*; D012680:Sensitivity and Specificity
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D011994:Recombinant Proteins
keywords: Brazil; Diagnosis; Leprosy; Mycobacterium leprae; Serology