Viral infections are important causative agents in renal disease and are responsible for significant morbidity and mortality. Of particular interest are those viral infections with productive replication in the kidney, which often occur in immunocompromized hosts such as renal allograft recipients. Epstein-Barr virus, cytomegalovirus, adenovirus and polyomavirus (type BK) are prominent members of this group causing specific diseases. Other viruses lack direct histological evidence of viral replication in the kidney, such as hepatitis C or human immunodeficiency virus (HIV). They are associated with renal disorders in immunocompetent and/or immunocompromised hosts, and glomerular or tubulo-interstitial¹¹ injury can be caused via indirect pathways, such as the deposition of immune complexes or cryoglobulins. Glomerular or tubulo-interstitial injury is frequently caused via indirect pathways, such as circulating immune complexes or cryoglobulins. This review will highlight selected viral diseases affecting the kidneys. Emphasis is placed on key morphological criteria, the use of ancillary studies (immunohistochemical staining, electron microscopy) and serologic techniques useful for the histopathologist to establish a step-wise diagnostic approach.

Viral infections can cause various renal diseases; however, it is often difficult to establish a clear pathogenetic link. Disease is well defined for viruses replicating in the renal parenchyma, such as Cytomegalovirus or Epstein-Barr virus whereas for others, a causative role in renal disease has not been firmly established, such as mumps and measles. The criteria for establishing a diagnosis are complex and, in most instances, involve correlation of clinical and laboratory data with the histomorphologic, immunohistochemical, and electron microscopical findings. Occasionally, polymerase chain reaction (PCR) and in situ hybridization techniques are required to confirm a specific diagnosis.

Symptoms of a kidney infection might include:

• Fever

• Chills

• A burning feeling or pain when urinating

• Having to urinate often

• A strong, lasting urge to urinate

• Back, side or groin pain

• Nausea and vomiting

• Pus or blood in the urine

• Urine that smells bad or is cloudy

• Belly pain

Urinalysis. This test checks urine for red and white blood cells, infection, or too much protein. Blood tests. Tests to measure the levels of waste products to find out how well the kidneys are filtering. Ultrasound of the kidney. This test uses high-frequency sound waves and a computer to make images of blood vessels, tissues, and organs.

Treatments focus on slowing the progression of the disease and preventing complications. Treatment may include: Blood pressure medicines such as ACE (angiotensin-converting enzymes) inhibitors that protect blood flow into the kidneys.

Unfortunately, kidney disease cannot be cured.Treatments focus on slowing the progression of the disease and preventing complications.Treatment may include: Blood pressure medicines such as ACE (angiotensin-converting enzymes) inhibitors that protect blood flow into the kidneys.

• May be entitled to special monthly compensation where the Veteran has a single service-connected disability rated as 100% with additional service-connected disability or disabilities independently ratable at 60% or more, which are separate and distinct from the 100% service-connected disability and involves different anatomical segments or bodily systems. See  38 CFR 3.350(i)(1) – Special Monthly Compensation (SMC).

• A report of the Institute of Medicine of the National Academy of Sciences has identified some long-term health effects, listed in the table embedded within 38 CFR 3.317(d), that potentially are associated with the infectious diseases listed in 38 CFR 3.317(c)(2). These health effects and diseases are listed alphabetically and are not categorized by the level of association stated in the National Academy of Sciences report. If a Veteran who has or had an infectious disease identified in column A also has a condition identified in column B as potentially related to that infectious disease, VA must determine, based on the evidence in each case, whether the column B condition was caused by the infectious disease for purposes of paying disability compensation. This does not preclude a finding that other manifestations of disability or secondary conditions were caused by an infectious disease. See 38 CFR 3.317(d) - Long-term health effects potentially associated with infectious diseases.

• If a Veteran presumed service connected for one of the diseases listed in 38 CFR 3.317(c)(2) is diagnosed with one of the diseases listed in column “B” in the table embedded within 38 CFR 3.317(d)  within the time period specified for the disease in the same table, if a time period is specified or, otherwise, at any time, VA will request a medical opinion as to whether it is at least as likely as not that the condition was caused by the Veteran having had the associated disease in column “A” in that same table. See 38 CFR 3.317(d) - Long-term health effects potentially associated with infectious diseases.

• When evaluating any claim involving loss or loss of use of one or more creative organs, refer to 38 CFR 3.350 of this chapter to determine whether the Veteran may be entitled to special monthly compensation. Footnotes in the schedule indicate conditions which potentially establish entitlement to special monthly compensation; however, there are other conditions in this section which under certain circumstances also establish entitlement to special monthly compensation.

• GFR, estimated GFR (eGFR), and creatinine-based approximations of GFR will be accepted for evaluation purposes when determined to be appropriate and calculated by a medical professional.