title: Utility of Loop-mediated Isothermal Amplification Assay, Polymerase Chain Reaction, and ELISA for Diagnosis of Leptospirosis in South Indian Patients.
abstract: BACKGROUND
  Leptospirosis is a zoonotic disease which requires laboratory diagnosis for confirmation.
  
  
  METHODS
  In this study serum samples from adults with acute undifferentiated fever (duration ≤15 days) were tested for IgM antibodies toLeptospiraby ELISA, PCR forrrsgene and loop-mediated isothermal amplification (LAMP) assay for LipL32 and LipL41.
  
  
  RESULTS
  Among the 150 sera tested, three were positive by PCR, LAMP and IgM ELISA/modified Faines' criteria, two by only PCR; seven only by LAMP assay and forty fulfilled modified Faine's criteria (illness clinically compatible and IgM ELISA positive for leptospirosis). Clinical correlation revealed renal compromise, low platelet count and severe jaundice were significantly related to leptospirosis (P< 0.05).
  
  
  CONCLUSIONS
  This study suggests that LAMP assay could be useful for diagnosis of leptospirosis during the 1stweek of illness whereas IgM ELISA forms the mainstay of diagnosis from the 2ndweek onward. Further studies especially community based, comparing ELISA, PCR, LAMP, culture and microscopic agglutination test are required to evaluate the veracity of these findings.
authors.affiliation: Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Mallika
authors.initials: M
authors.lastname: Sengupta
authors.affiliation: Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Abhilash Kundavaram Paul
authors.initials: AK
authors.lastname: Prabhakar
authors.affiliation: Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Sowmya
authors.initials: S
authors.lastname: Satyendra
authors.affiliation: Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: David
authors.initials: D
authors.lastname: Thambu
authors.affiliation: Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Ooriapadickal Cherian
authors.initials: OC
authors.lastname: Abraham
authors.affiliation: Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: Veeraraghavan
authors.initials: V
authors.lastname: Balaji
authors.affiliation: Viral and Rickettsial Diseases Department, Infectious Diseases Directorate, Naval Medical Research Center, Silver Spring, MD 20910, USA.
authors.forename: Hua-Wei
authors.initials: HW
authors.lastname: Chen
authors.affiliation: Viral and Rickettsial Diseases Department, Infectious Diseases Directorate, Naval Medical Research Center, Silver Spring, MD 20910, USA.
authors.forename: Chien-Chung
authors.initials: CC
authors.lastname: Chao
authors.affiliation: Viral and Rickettsial Diseases Department, Infectious Diseases Directorate, Naval Medical Research Center, Silver Spring, MD 20910, USA.
authors.forename: Wei-Mei
authors.initials: WM
authors.lastname: Ching
authors.affiliation: Department of Clinical Microbiology, Christian Medical College, Vellore, Tamil Nadu, India.
authors.forename: John Antony Jude
authors.initials: JA
authors.lastname: Prakash
keywords: Diagnosis; IgM ELISA; leptospirosis; loop-mediated isothermal amplification; polymerase chain reaction; serum