Acute proliferative glomerulonephritis is a disorder of the glomeruli

Glomerulus

A glomerulus is a capillary tuft that is involved in the first step of filtering blood to form urine.A glomerulus is surrounded by Bowman's capsule, the beginning component of nephrons in the vertebrate kidney. A glomerulus receives its blood supply from an afferent arteriole of the renal...

 (glomerulonephritis

Glomerulonephritis

Glomerulonephritis, also known as glomerular nephritis, abbreviated GN, is a renal disease characterized by inflammation of the glomeruli, or small blood vessels in the kidneys...

), or small blood vessels in the kidneys. It is a common complication of infections, typically streptococcal skin infection (impetigo

Impetigo

Impetigo is a highly contagious bacterial skin infection most common among pre-school children. People who play close contact sports such as rugby, American football and wrestling are also susceptible, regardless of age. Impetigo is not as common in adults. The name derives from the Latin impetere...

) rather than streptococcal pharyngitis, for which it is also known as postinfectious or poststreptococcal glomerulonephritis.

It can be a risk factor for future albuminuria

Albuminuria

Albuminuria is a pathological condition wherein albumin is present in the urine. It is a type of proteinuria.Measurement=The amount of protein being lost in the urine can be quantified by collecting the urine for 24 hours, measuring a sample of the pooled urine, and extrapolating to the volume...

.

Causes

Acute proliferative glomerulonephritis can be a complication of streptococcal pharyngitis (strep throat) and impetigo

Impetigo

Impetigo is a highly contagious bacterial skin infection most common among pre-school children. People who play close contact sports such as rugby, American football and wrestling are also susceptible, regardless of age. Impetigo is not as common in adults. The name derives from the Latin impetere...

.

Pathophysiology

The exact pathology remains unclear, but it is believed to be type III hypersensitivity

Type III hypersensitivity

Type III hypersensitivity occurs when antigens and antibodies are present in roughly equal amounts, causing extensive cross-linking.-Presentation:...

 reaction. Immune complexes (antigen-antibody complexes formed during an infection) become lodged in the glomerular basement membrane

Glomerular basement membrane

The glomerular basement membrane is the basal laminal portion of the glomerulus. The Glomerular capillary endothelial cells, the GBM and the filtration slits between the podocytes perform the filtration function of the glomerulus, separating the blood in the capillaries from the filtrate that...

 below the podocyte foot processes. This creates a lumpy bumpy appearance on light microscopy and subepithelial humps on electron microscopy. Complement

Complement system

The complement system helps or “complements” the ability of antibodies and phagocytic cells to clear pathogens from an organism. It is part of the immune system called the innate immune system that is not adaptable and does not change over the course of an individual's lifetime...

 activation leads to destruction of the basement membrane. It has also been proposed that specific antigens from certain nephrotoxic streptococcal infections have a high affinity for basement membrane proteins, giving rise to particularly severe, long lasting antibody response.

Diagnosis

Diagnosis rarely requires a renal biopsy

Renal biopsy

A renal biopsy is a procedure in which a sample of kidney tissue is obtained. Microscopic examination of the tissue can provide information needed to diagnose, monitor or treat a renal disorder.-Indications:...

 since there is usually a classical clinical presentation. There will be elevated levels of ASOT Ab and low complement levels (C3 and C4) in the blood.

Presentation

1) Hematuria

Hematuria

In medicine, hematuria, or haematuria, is the presence of red blood cells in the urine. It may be idiopathic and/or benign, or it can be a sign that there is a kidney stone or a tumor in the urinary tract , ranging from trivial to lethal...

:

• May be microscopic and not identified by the patient.

• May be macroscopic and lead to dark brown or smoky urine.

• Frank hematuria may occur in severe case.

2) Oliguria

Oliguria

Oliguria is the low output of urine, It is clinically classified as an output below 300-500ml/day. The decreased output of urine may be a sign of dehydration, renal failure, hypovolemic shock, HHNS Hyperosmolar Hyperglycemic Nonketotic Syndrome, multiple organ dysfunction syndrome, urinary...

• Urine output is less than 400 ml/day (normally 600 to 2500 ml/day). In children less than 0.5 mL/ kg/ hr

• May not be observed by the patient.

3) Edema

• Acute onset.

• Mild to modest severity.

• Pitting edema.

• Starts in the eyelids and face then the lower and upper limbs then generalized (Hydrocele
  Hydrocele
  A hydrocoele denotes a pathological accumulation of serous fluid in a body cavity. It can also be noted as a minor malformation of newborns due to high levels of lead in the mother's blood during pregnancy....
  
  , ascites
  Ascites
  Ascites is a gastroenterological term for an accumulation of fluid in the peritoneal cavity.The medical condition is also known as peritoneal cavity fluid, peritoneal fluid excess, hydroperitoneum or more archaically as abdominal dropsy. Although most commonly due to cirrhosis and severe liver...
  
  . Pericardial
  Pericardial effusion
  Pericardial effusion is an abnormal accumulation of fluid in the pericardial cavity. Because of the limited amount of space in the pericardial cavity, fluid accumulation will lead to an increased intrapericardial pressure and this can negatively affect heart function...
  
   and pleural effusion
  Pleural effusion
  Pleural effusion is excess fluid that accumulates between the two pleural layers, the fluid-filled space that surrounds the lungs. Excessive amounts of such fluid can impair breathing by limiting the expansion of the lungs during ventilation.-Pathophysiology:...
  
  .)

• It may be migratory: appear in eyelid in the morning, disappear in the afternoon and reappear around the ankle in the ambulant patients by the end of the day.

4) Hypertension.

• It is usually mild to moderate.

• Hypertensive encephalopathy
  Encephalopathy
  Encephalopathy means disorder or disease of the brain. In modern usage, encephalopathy does not refer to a single disease, but rather to a syndrome of global brain dysfunction; this syndrome can be caused by many different illnesses.-Terminology:...
  
  , heart failure and acute pulmonary edema
  Pulmonary edema
  Pulmonary edema , or oedema , is fluid accumulation in the air spaces and parenchyma of the lungs. It leads to impaired gas exchange and may cause respiratory failure...
  
   may occur in severe cases.

• Pulmonary congestion and congested neck veins may be present, but usually due to salt and water retention and less commonly heart failure.

5) General

• Fever, headache, malaise
  Malaise
  Malaise is a feeling of general discomfort or uneasiness, of being "out of sorts", often the first indication of an infection or other disease. Malaise is often defined in medicinal research as a "general feeling of being unwell"...
  
  , anorexia, nausea and vomiting.

• Pallor due to edema and/or anemia.

6) Acute renal necrosis due to injury of capillary or capillary thrombosis.

• Acute tubular obstruction by cast.

Mechanism of edema

Diffuse Proliferative Glomerulonephritis (DPGN) is a nephritic syndrome; therefore, it causes edema through an increase in hydrostatic pressure and fluid overload secondary to inflammatory damage. Examples of nephritic syndrome include: DPGN, IgA nephropathy, Lupus nephritis, and MPGN.

Hypoalbuminemia is the cause of edema in nephrotic syndrome (characterized by heavy proteinuria—greater than 3.5g/day). Examples include: Minimal Change Disease (MCD), Membranous Glomerulonephritis (MGN), Focal Segmental Glomerulosclerosis (FSGS), Lupus, Amyloidosis, and Diabetes.

Differential diagnosis

1. Other causes of acute glomerulonephritis:
   • IgA Nephropathy
   • Lupus nephritis
     Lupus nephritis
     Lupus nephritis is an inflammation of the kidney caused by systemic lupus erythematosus , a disease of the immune system. Apart from the kidneys, SLE can also damage the skin, joints, nervous system and virtually any organ or system in the body....
     
     
   • Type 1 membranoproliferative glomerulonephritis
   • Bacterial endocarditis
     Endocarditis
     Endocarditis is an inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves . Other structures that may be involved include the interventricular septum, the chordae tendineae, the mural endocardium, or even on intracardiac devices...
     
     
   • Shunt nephritis
     Shunt nephritis
     Shunt nephritis is a rare disease of the kidney that can occur in patients being treated for hydrocephalus with a cerebral shunt. It usually results from an infected shunt that produces a long-standing blood infection, particularly by the bacterium Staphylococcus epidermidis. Kidney disease results...
     
     
   • Cryoglobulinemia
     Cryoglobulinemia
     Cryoglobulinemia is a medical condition in which the blood contains large amounts of cryoglobulins - proteins that become insoluble at reduced temperatures. Cryoglobulins typically precipitate at temperatures below normal body temperature and will dissolve again if the blood is heated...
     
     
2. Nephrotic syndrome
3. Other causes of generalized edema:
   • Malnutrition
   • Malabsorption
   • Renal affection
   • Liver cell failure
   • Right side heart failure
   • Angioedema
     Angioedema
     Angioedema or Quincke's edema is the rapid swelling of the dermis, subcutaneous tissue, mucosa and submucosal tissues. It is very similar to urticaria, but urticaria, commonly known as hives, occurs in the upper dermis...
     
     
4. Other causes of hematuria

Complications

Possible complications of acute proliferative glomerulonephritis include renal failure

Renal failure

Renal failure or kidney failure describes a medical condition in which the kidneys fail to adequately filter toxins and waste products from the blood...

 and hypertensive encephalopathy

Hypertensive encephalopathy

Hypertensive encephalopathy is a neurological dysfunction induced by malignant hypertension. The term "hypertensive encephalopathy" was introduced to describe this type of encephalopathy by Oppenheimer and Fishberg in 1928. It describes cerebral conditions, typically reversible, caused by sudden...

.

External links

• Post-infectious glomerulonephritis - Mayo Clinic
  Mayo Clinic
  Mayo Clinic is a not-for-profit medical practice and medical research group specializing in treating difficult patients . Patients are referred to Mayo Clinic from across the U.S. and the world, and it is known for innovative and effective treatments. Mayo Clinic is known for being at the top of...
  
  
• Group A Streptococcal Infections - National Institute of Allergy and Infectious Diseases
  National Institute of Allergy and Infectious Diseases
  The National Institute of Allergy and Infectious Diseases is one of the 27 institutes and centers that make up the National Institutes of Health , an agency of the United States Department of Health and Human Services...