title: Overlooked Risk for Chronic Kidney Disease after Leptospiral Infection: A Population-Based Survey and Epidemiological Cohort Evidence.
abstract: BACKGROUND
  Leptospirosis is the most widespread zoonosis. Chronic human infection and asymptomatic colonization have been reported. However, renal involvement in those with leptospira chronic exposure remains undetermined.
  
  
  RESULTS
  In 2007, a multistage sampling survey for chronic kidney disease (CKD) was conducted in a southern county of Taiwan, an area with a high prevalence of dialysis. Additionally, an independent cohort of 88 participants from a leptospira-endemic town was followed for two years after a flooding in 2009. Risks of CKD, stages of CKD, associated risk factors as well as kidney injury markers were compared among adults with anti-leptospira antibody as defined by titers of microscopic agglutination test (MAT). Of 3045 survey participants, the individuals with previous leptospira exposure disclosed a lower level of eGFR (98.3 ± 0.4 vs 100.8 ± 0.6 ml/min per 1.73 m2, P < 0.001) and a higher percentage of CKD, particularly at stage 3a-5 (14.4% vs 8.5%), than those without leptospira exposure. Multivariable linear regression analyses indicated the association of leptospiral infection and lower eGFR (95% CI -4.15 to -1.93, P < 0.001). In a leptospiral endemic town, subjects with a MAT titer ≥ 400 showed a decreased eGFR and higher urinary kidney injury molecule-1 creatinine ratio (KIM1/Cr) level as compared with those having lower titers of MAT (P < 0.05). Furthermore, two participants with persistently high MAT titers had positive urine leptospira DNA and deteriorating renal function.
  
  
  CONCLUSIONS
  Our data are the first to show that chronic human exposure of leptospirosis is associated significantly with prevalence and severity of CKD and may lead to deterioration of renal function. This study also shed light on the search of underlying factors in areas experiencing CKD of unknown aetiology (CKDu) such as Mesoamerican Nephropathy.
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan; Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America.
authors.forename: Huang-Yu
authors.initials: HY
authors.lastname: Yang
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Cheng-Chieh
authors.initials: CC
authors.lastname: Hung
authors.affiliation: Department of Family Medicine, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Taoyuan, Taiwan.
authors.forename: Su-Hsun
authors.initials: SH
authors.lastname: Liu
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Yi-Gen
authors.initials: YG
authors.lastname: Guo
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Yung-Chang
authors.initials: YC
authors.lastname: Chen
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Yi-Ching
authors.initials: YC
authors.lastname: Ko
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Chiung-Tseng
authors.initials: CT
authors.lastname: Huang
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Li-Fang
authors.initials: LF
authors.lastname: Chou
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Ya-Chung
authors.initials: YC
authors.lastname: Tian
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Ming-Yang
authors.initials: MY
authors.lastname: Chang
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Hsiang-Hao
authors.initials: HH
authors.lastname: Hsu
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors.forename: Ming-Yen
authors.initials: MY
authors.lastname: Lin
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
authors.forename: Shang-Jyh
authors.initials: SJ
authors.lastname: Hwang
authors.affiliation: Kidney Research Center, Department of Nephrology, Chang Gung Memorial Hospital, Chang Gung University, College of Medicine, Taoyuan, Taiwan.
authors.forename: Chih-Wei
authors.initials: CW
authors.lastname: Yang
mesh_terms: D000328:Adult; D000372:Agglutination Tests; D015331:Cohort Studies; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007922:Leptospirosis / Q000150:complications*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000209:etiology*; D012306:Risk