Leptospirosis and Chronic Kidney Disease

Leptospirosis is the most prevalent zoonosis affecting more than 1 million people worldwide. Acute leptospirosis induces multiple organ dysfunctions including acute kidney injury. Interestingly, the endemic regions of leptospirosis coincide with chronic kidney disease of unknown (CKDu) etiology hotspots. Histology findings of leptospirosis renal disease include tubulointerstitial nephritis, interstitial fibrosis, and tubular atrophy. Proximal tubule dysfunction and hypokalemia are observed in adult male workers with leptospirosis, a characteristic similar to CKDu. Leptospirosis has been considered as a risk factor for CKDu in Sri Lanka and in Mesoamerican area. In fact, populations with anti-leptospira seropositivity are associated with lower estimated glomerular filtration rate and higher prevalence of CKD in endemic areas. Together, evidence suggests that for field workers with leptospiral colonization in the kidneys, exposure to extreme heat and dehydration may serve as a "second hit" in the development of CKD. The precise mechanism for chronic leptospira colonization is still under investigation, and recent research has suggested Treg to play a role in leptospira tolerance. The fact that most of the leptospiral infections are presented as subclinical symptoms makes diagnosis and early intervention difficult, predisposing the patients to possible chronic carrier state and increased risk for renal fibrosis and CKDu. Thus, leptospirosis is an emerging culprit of CKDu that deserves further in-depth investigation.