title: A comparison of ML Flow serology and slit skin smears to assess the bacterial load in newly diagnosed leprosy patients in Brazil.
abstract: BACKGROUND
  The ML Flow test is an immunochromatographic assay that detects IgM antibodies against M. leprae-specific anti-phenolic glycolipid I (PGL-I). In addition to slit skin smears stained by the Ziehl-Neelsen technique, it can be helpful in the operational classification of leprosy patients for treatment purposes.
  
  
  OBJECTIVE
  This work studied the relationship between antibody levels as detected by semi-quantitative ML Flow serologic test and bacterial load as quantified by slit skin smear.
  
  
  METHODS
  135 patients with newly detected leprosy at the reference service in Sanitary Dermatology in Brazil had slit skin smears (registered as bacillary index - BI) and an ML Flow test (registered qualitatively and semi-quantitatively) performed at admission. A logistic regression and agreement measures (kappa index) were calculated.
  
  
  RESULTS
  Slit skin smears were positive in 35.9% of patients and 57% of patients were seropositive for PGL-1 antibodies. Among the seropositive patients, 416% had five or fewer skin lesions, and 65.8% had more than one peripheral nerve involved. Slit skin smears were positive in only three seronegative patients (5.6%), and negative in 41.9% of seropositive patients. Patients with a BI of 4 + had an OR of 33 for being seropositive in comparison to those with a low BI.
  
  
  CONCLUSIONS
  There is a correlation between serologic test and slit skin smear results. Therefore, an ML Flow test may become a useful tool in the clinical classification of leprosy, besides slit skin smears, which require a proper laboratory infrastructure and experienced personnel.
authors: Sanitary Dermatology Service, Hospital Eduardo de Menezes, Fundação Hospitalar do Estado de Minas Gerais, Belo Horizonte, Brazil. sandralyon@ig.com.br
authors: Sandra
authors: S
authors: Lyon
authors: Ana Claudia
authors: AC
authors: Lyon
authors: Rozana Castorina
authors: RC
authors: Da Silva
authors: Maria Aparecida De Faria
authors: MA
authors: Grossi
authors: Silvia Helena
authors: SH
authors: Lyon
authors: Samira
authors: S
authors: Bührer-Sékula
authors: Manoel O C
authors: MO
authors: Rocha
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D000942:Antigens, Bacterial / Q000378:metabolism; D001431:Bacteriological Techniques; D001938:Brazil / Q000453:epidemiology; D005260:Female; D006017:Glycolipids / Q000378:metabolism; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D007918:Leprosy / Q000382:microbiology*; D008297:Male; D025202:Molecular Diagnostic Techniques; D009166:Mycobacterium leprae / Q000276:immunology / Q000502:physiology*; D012867:Skin / Q000382:microbiology / Q000473:pathology*; D013194:Staining and Labeling
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D006017:Glycolipids; D007075:Immunoglobulin M; C045169:phenolic glycolipid I, Mycobacterium leprae