Glomerulonephritis (GN) is a term used to refer to several kidney diseases (usually affecting both kidneys). 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. As it is not strictly a single disease, its presentation depends on the specific disease entity: it may present with isolated hematuria and/or proteinuria (blood or protein in the urine); or as a nephrotic syndrome, a nephritic syndrome, acute kidney injury, or chronic kidney disease. They are categorized into several different pathological patterns, which are broadly grouped into non-proliferative or proliferative types. Diagnosing the pattern of GN is important because the outcome and treatment differ in different types. Primary causes are intrinsic to the kidney. Secondary causes are associated with certain infections (bacterial, viral or parasitic pathogens), drugs, systemic disorders (SLE, vasculitis), or diabetes. Signs and symptoms
Glomerulonephritis refers to an inflammation of the glomerulus, which is the unit involved in filtration in the kidney. This inflammation typically results in one or both of the nephrotic or nephritic syndromes. : 500

Nephrotic syndrome
The nephrotic syndrome is characterised by the finding of edema in a person with increased protein in the urine and decreased protein in the blood, with increased fat in the blood. Inflammation that affects the cells surrounding the glomerulus, podocytes, increases the permeability to proteins, resulting in an increase in excreted proteins.
Diagnosis
Types
Granuloma annulare may be divided into the following types:: 703–5 
Localized granuloma annulare
Generalized granuloma annulare
Patch-type granuloma annulare
Subcutaneous granuloma annulare
Perforating granuloma annulare

Treatment
Because granuloma annulare is usually asymptomatic and self-limiting with a course of about 2 years, initial treatment is generally topical steroids or calcineurin inhibitors; if unimproved with topical treatments, it may be treated with intradermal injections of steroids. If local treatment fails it may be treated with systemic corticosteroids. Treatment success varies widely, with most patients finding only brief success with the above-mentioned treatments. Most lesions of granuloma annulare disappear in pre-pubertal patients with no treatment within two years while older patients (50+) have rings for upwards of 20 years. The appearance of new rings years later is not uncommon. History
The disease was first described in 1895 by Thomas Colcott Fox as a "ringed eruption of the fingers", and it was named granuloma annulare by Henry Radcliffe Crocker in 1902. See also
Granuloma
Necrobiosis lipoidica

References
External links
DermNet dermal-infiltrative/granuloma-annulare