Renal Infectious Diseases

Infectious diseases are a major cause of morbidity and mortaLity in humans throughout the world. Renal involvement by a variety of infectious etiologies either in isolation or during widespread dissemination can result in significant organ dysfunction. Viruses, such as human polyomavirus or adenovirus, can directly infect kidney tubular epitheLial cells and induce tubulointerstitial inflammatory responses. Alternatively, the immune response of the host to offending viruses, such as hepatitis B, hepatitis C virus, or human immunodeficiency virus, can lead to immune complex formation resulting in a variety of glomerular patterns of injury. Fungal and mycobacterial infections injure primarily through direct colonization of the kidney, which may be exacerbated by the associated inflammatory response to the initial infection. The kidney has a Limited number of ways to respond to the wide array of infectious agents. Therefore, there are many overlapping histopathologic features, and definitive identification of the offending microorganism based on a kidney biopsy can be a diagnostic challenge. The wide spectrum of renal diseases in humans caused by common viral, fungal, and mycobacterial pathogens will be reviewed. Bacterial infections involving the kidney will be discussed elsewhere.