HIV-associated nephropathy (HIVAN) refers to

kidney disease Kidney disease, or renal disease, technically referred to as nephropathy, is damage to or disease of a kidney. Nephritis is an Inflammation, inflammatory kidney disease and has several types according to the location of the inflammation. Infla ...

developing in association with infection by

human immunodeficiency virus The human immunodeficiency viruses (HIV) are two species of ''Lentivirus'' (a subgroup of retrovirus) that infect humans. Over time, they cause AIDS, acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of th ...

, the virus that causes

AIDS The HIV, human immunodeficiency virus (HIV) is a retrovirus that attacks the immune system. Without treatment, it can lead to a spectrum of conditions including acquired immunodeficiency syndrome (AIDS). It is a Preventive healthcare, pr ...

. The most common, or "classical", type of HIV-associated nephropathy is a collapsing

focal segmental glomerulosclerosis Focal segmental glomerulosclerosis (FSGS) is a histopathologic finding of scarring (sclerosis) of glomeruli and damage to renal podocytes. This process damages the filtration function of the kidney, resulting in protein presence in the urine du ...

(FSGS), though other forms of kidney disease may also occur. Regardless of the underlying

histology Histology, also known as microscopic anatomy or microanatomy, is the branch of biology that studies the microscopic anatomy of biological tissue (biology), tissues. Histology is the microscopic counterpart to gross anatomy, which looks at large ...

, kidney disease in HIV-positive patients is associated with an increased risk of death.

Cause

HIVAN may be caused by direct infection of the kidney cells by HIV, with resulting kidney damage through the viral gene products. It could also be caused by the release of

cytokines Cytokines () are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Cytokines are produced by a broad range of cells, including immune cells like macrophages, B cell, B lymphocytes, T cell, T lymphocytes ...

during HIV infection. Usually occurs only in advanced HIV disease and approximately 80% of patients with HIVAN have a

CD4 In molecular biology, CD4 (cluster of differentiation 4) is a glycoprotein that serves as a co-receptor for the T-cell receptor (TCR). CD4 is found on the surface of immune cells such as helper T cells, monocytes, macrophages, and dendritic c ...

count of less than 200. HIVAN presents with

nephrotic syndrome Nephrotic syndrome is a collection of symptoms due to kidney damage. This includes proteinuria, protein in the urine, hypoalbuminemia, low blood albumin levels, hyperlipidemia, high blood lipids, and significant edema, swelling. Other symptoms ...

and progressive

kidney failure Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney fa ...

. Despite being a cause of chronic kidney failure, kidney sizes are usually normal or large.

Pathology

Abnormalities involve all components of the

nephron The nephron is the minute or microscopic structural and functional unit of the kidney. It is composed of a renal corpuscle and a renal tubule. The renal corpuscle consists of a tuft of capillaries called a glomerulus and a cup-shaped structu ...

. Typical findings are that of collapsing capillary loops, areas of scarring called focal segmental glomerulosclerosis (

FSGS Focal segmental glomerulosclerosis (FSGS) is a histopathologic finding of scarring Sclerosis (medicine), (sclerosis) of Glomerulus (kidney), glomeruli and damage to renal podocytes. This process damages the filtration function of the kidney, resul ...

), microcystic tubular dilatation that is highly echogenic, and prominent podocytes.The characteristic feature of collapsing glomerulopathy is collapse of glomerular tuft and proliferation and hyperplasia of glomerular visceral epithelial cells. Its prognosis is always poor, as it rapidly progresses to

chronic kidney disease Chronic kidney disease (CKD) is a type of long-term kidney disease, defined by the sustained presence of abnormal kidney function and/or abnormal kidney structure. To meet criteria for CKD, the abnormalities must be present for at least three mo ...

Treatment

There are no adequate data from randomised controlled trials. Treatment with

highly active antiretroviral therapy The management of HIV/AIDS normally includes the use of multiple antiretroviral drugs as a strategy to control HIV infection. There are several classes of antiretroviral agents that act on different stages of the HIV life-cycle. The use of mul ...

and

angiotensin converting enzyme inhibitors Angiotensin-converting-enzyme inhibitors (ACE inhibitors) are a class of medication used primarily for the treatment of high blood pressure and heart failure. This class of medicine works by causing relaxation of blood vessels as well as a decr ...

angiotensin receptor blockers Angiotensin II receptor blockers (ARBs), formally angiotensin II receptor type 1 (AT1) antagonists, also known as angiotensin receptor blockers, angiotensin II receptor antagonists, or AT1 receptor antagonists, are a group of pharmaceuticals tha ...

has been shown to be beneficial and should be given to all patients unless otherwise contraindicated. General renoprotective measures and the treatment of the complications of nephrotic syndrome and kidney failure are adjunctive.

Corticosteroid Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are invo ...

treatment can be useful in patients who do not respond to initial treatment. There is some evidence that

ciclosporin Ciclosporin, also spelled cyclosporine and cyclosporin, is a calcineurin inhibitor, used as an immunosuppressant medication. It is taken Oral administration, orally or intravenously for rheumatoid arthritis, psoriasis, Crohn's disease, nephr ...

might be helpful in selective cases, however further study of both steroids and ciclosporin is needed before these types of drugs can be considered standard treatment.

Incidence

HIVAN is the third most common cause of end stage

among African Americans, and commonly seen in African-American patients with HIV compared to other ethnic groups. In the USA 12% of patients dying with AIDS have histologically proven HIVAN, the worldwide incidence amongst AIDS patients appears to be similar. A South African study at

Tygerberg Hospital Tygerberg Hospital is a tertiary public hospital located in Parow. The hospital was officially opened in 1976 and is the largest district general hospital in the Western Cape and the second largest hospital in South Africa, with the capacity fo ...

Stellenbosch University Stellenbosch University (SU) (, ) is a public research university situated in Stellenbosch, a town in the Western Cape province of South Africa. Stellenbosch is the oldest university in South Africa and the oldest extant university in Sub-Sahara ...

, has shown HIVAN histology in 33/61(54%)

biopsies A biopsy is a medical test commonly performed by a surgeon, an interventional radiologist, or an interventional cardiologist. The process involves the extraction of sample cells or tissues for examination to determine the presence or extent of ...

performed in HIV positive patients.

References

External links

{{AIDS Kidney diseases HIV/AIDS