HIV-associated nephropathy | |
---|---|
Specialty | Nephrology |
HIV-associated nephropathy (HIVAN) refers to kidney disease developing in association with infection by human immunodeficiency virus, the virus that causes AIDS. The most common, or "classical", type of HIV-associated nephropathy is a collapsing focal segmental glomerulosclerosis (FSGS), though other forms of kidney disease may also occur. [1] Regardless of the underlying histology, kidney disease in HIV-positive patients is associated with an increased risk of death. [2]
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 during HIV infection. Usually occurs only in advanced HIV disease and approximately 80% of patients with HIVAN have a CD4 count of less than 200. HIVAN presents with nephrotic syndrome and progressive kidney failure. Despite being a cause of chronic kidney failure, kidney sizes are usually normal or large.[ citation needed ]
Abnormalities involve all components of the nephron. Typical findings are that of collapsing capillary loops, areas of scarring called focal segmental glomerulosclerosis (FSGS), 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.[ citation needed ]
There are no adequate data from randomised controlled trials.[ citation needed ]
Treatment with highly active antiretroviral therapy and angiotensin converting enzyme inhibitors or angiotensin receptor blockers 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.[ citation needed ]
Corticosteroid treatment can be useful in patients who do not respond to initial treatment. There is some evidence that ciclosporin 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.[ citation needed ]
HIVAN is the third most common cause of end stage kidney failure 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, Stellenbosch University, has shown HIVAN histology in 33/61(54%) biopsies performed in HIV positive patients.[ citation needed ]
Proteinuria is the presence of excess proteins in the urine. In healthy persons, urine contains very little protein; an excess is suggestive of illness. Excess protein in the urine often causes the urine to become foamy. Severe proteinuria can cause nephrotic syndrome in which there is worsening swelling of the body.
Nephrotic syndrome is a collection of symptoms due to kidney damage. This includes protein in the urine, low blood albumin levels, high blood lipids, and significant swelling. Other symptoms may include weight gain, feeling tired, and foamy urine. Complications may include blood clots, infections, and high blood pressure.
Kidney failure, also known as end-stage kidney disease, 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 failure is classified as either acute kidney failure, which develops rapidly and may resolve; and chronic kidney failure, which develops slowly and can often be irreversible. Symptoms may include leg swelling, feeling tired, vomiting, loss of appetite, and confusion. Complications of acute and chronic failure include uremia, hyperkalaemia, and volume overload. Complications of chronic failure also include heart disease, high blood pressure, and anaemia.
Nephritis is inflammation of the kidneys and may involve the glomeruli, tubules, or interstitial tissue surrounding the glomeruli and tubules. It is one of several different types of nephropathy.
Kidney disease, or renal disease, technically referred to as nephropathy, is damage to or disease of a kidney. Nephritis is an inflammatory kidney disease and has several types according to the location of the inflammation. Inflammation can be diagnosed by blood tests. Nephrosis is non-inflammatory kidney disease. Nephritis and nephrosis can give rise to nephritic syndrome and nephrotic syndrome respectively. Kidney disease usually causes a loss of kidney function to some degree and can result in kidney failure, the complete loss of kidney function. Kidney failure is known as the end-stage of kidney disease, where dialysis or a kidney transplant is the only treatment option.
Chronic kidney disease (CKD) is a type of kidney disease in which a gradual loss of kidney function occurs over a period of months to years. Initially generally no symptoms are seen, but later symptoms may include leg swelling, feeling tired, vomiting, loss of appetite, and confusion. Complications can relate to hormonal dysfunction of the kidneys and include high blood pressure, bone disease, and anemia. Additionally CKD patients have markedly increased cardiovascular complications with increased risks of death and hospitalization.
IgA nephropathy (IgAN), also known as Berger's disease, or synpharyngitic glomerulonephritis, is a disease of the kidney and the immune system; specifically it is a form of glomerulonephritis or an inflammation of the glomeruli of the kidney. Aggressive Berger's disease can attack other major organs, such as the liver, skin and heart.
Glomerulonephritis (GN) is a term used to refer to several kidney diseases. Many of the diseases are characterised by inflammation either of the glomeruli or of the small blood vessels in the kidneys, hence the name, but not all diseases necessarily have an inflammatory component.
Diabetic nephropathy, also known as diabetic kidney disease, is the chronic loss of kidney function occurring in those with diabetes mellitus. Diabetic nephropathy is the leading causes of chronic kidney disease (CKD) and end-stage renal disease (ESRD) globally. The triad of protein leaking into the urine, rising blood pressure with hypertension and then falling renal function is common to many forms of CKD. Protein loss in the urine due to damage of the glomeruli may become massive, and cause a low serum albumin with resulting generalized body swelling (edema) so called nephrotic syndrome. Likewise, the estimated glomerular filtration rate (eGFR) may progressively fall from a normal of over 90 ml/min/1.73m2 to less than 15, at which point the patient is said to have end-stage renal disease. It usually is slowly progressive over years.
Nephrotoxicity is toxicity in the kidneys. It is a poisonous effect of some substances, both toxic chemicals and medications, on kidney function. There are various forms, and some drugs may affect kidney function in more than one way. Nephrotoxins are substances displaying nephrotoxicity.
Hypertensive kidney disease is a medical condition referring to damage to the kidney due to chronic high blood pressure. It manifests as hypertensive nephrosclerosis. It should be distinguished from renovascular hypertension, which is a form of secondary hypertension, and thus has opposite direction of causation.
Membranous glomerulonephritis (MGN) is a slowly progressive disease of the kidney affecting mostly people between ages of 30 and 50 years, usually white people.
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 loss in the urine. FSGS is a leading cause of excess protein loss—nephrotic syndrome—in children and adults. Signs and symptoms include proteinuria, water retention, and edema. Kidney failure is a common long-term complication of disease. FSGS can be classified as primary versus secondary depending on whether a particular toxic or pathologic stressor can be identified as the cause. Diagnosis is established by renal biopsy, and treatment consists of glucocorticoids and other immune-modulatory drugs. Response to therapy is variable, with a significant portion of patients progressing to end-stage kidney failure. FSGS is estimated to occur in 2-3 persons per million, with males and African peoples at higher risk.
Congenital nephrotic syndrome is a rare kidney disease which manifests in infants during the first 3 months of life, and is characterized by high levels of protein in the urine (proteinuria), low levels of protein in the blood, and swelling. This disease is primarily caused by genetic mutations which result in damage to components of the glomerular filtration barrier and allow for leakage of plasma proteins into the urinary space.
Glomerulosclerosis is the hardening of the glomeruli in the kidney. It is a general term to describe scarring of the kidneys' tiny blood vessels, the glomeruli, the functional units in the kidney that filter urea from the blood.
Loin pain hematuria syndrome (LPHS) is the combination of debilitating unilateral or bilateral flank pain and microscopic or macroscopic amounts of blood in the urine that is otherwise unexplained.
Mesangial proliferative glomerulonephritis (MesPGN) is a morphological pattern characterized by a numerical increase in mesangial cells and expansion of the extracellular matrix within the mesangium of the glomerulus. The increase in the number of mesangial cells can be diffuse or local and immunoglobulin and/or complement deposition can also occur. MesPGN is associated with a variety of disease processes affecting the glomerulus, though can be idiopathic. The clinical presentation of MesPGN usually consists of hematuria or nephrotic syndrome. Treatment is often consistent with the histologic pattern of and/or disease process contributing to mesangial proliferative glomerulonephritis, and usually involves some form of immunosuppressant.
Glomerulonephrosis is a non-inflammatory disease of the kidney (nephrosis) presenting primarily in the glomerulus as Nephrotic Syndrome. The nephron is the functional unit of the kidney and it contains the glomerulus, which acts as a filter for blood to retain proteins and blood lipids. Damage to these filtration units results in important blood contents being released as waste in urine. This disease can be characterized by symptoms such as fatigue, swelling, and foamy urine, and can lead to chronic kidney disease and ultimately end-stage renal disease, as well as cardiovascular diseases. Glomerulonephrosis can present as either primary glomerulonephrosis or secondary glomerulonephrosis.
Diffuse proliferative glomerulonephritis (DPGN) is a type of glomerulonephritis that is the most serious form of renal lesions in SLE and is also the most common, occurring in 35% to 60% of patients. In absence of SLE, DPGN pathology looks more like Membranoproliferative glomerulonephritis
Sickle cell nephropathy is a type of nephropathy associated with sickle cell disease which causes kidney complications as a result of sickling of red blood cells in the small blood vessels. The hypertonic and relatively hypoxic environment of the renal medulla, coupled with the slow blood flow in the vasa recta, favors sickling of red blood cells, with resultant local infarction. Functional tubule defects in patients with sickle cell disease are likely the result of partial ischemic injury to the renal tubules.