Nephrotic syndrome is a collection of findings resulting from glomerular dysfunction with an increase in glomerular capillary wall permeability associated with pronounced proteinuria. Nephrotic syndrome refers to the constellation of clinical findings that result from severe renal loss of protein, with Proteinuria and hypoalbuminemia, edema, and hyperlipidemia.

A reduction in the level of performance of the kidneys in areas of function comprising the concentration of urine, removal of wastes, the maintenance of electrolyte balance, homeostasis of blood pressure, and calcium metabolism.

An increased susceptibility to pneumonia as manifested by a history of recurrent episodes of pneumonia.

A type of glomerulonephritis characterized by diffuse mesangial cell proliferation and the thickening of capillary walls due to subendothelial extension of the mesangium. The term membranoproliferative glomerulonephritis is often employed to denote a general pattern of glomerular injury seen in a variety of disease processes that share a common pathogenetic mechanism, rather than to describe a single disease entity

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by production of autoantibodies against nuclear, cytoplasmic, and cell surface molecules that transcend organ-specific boundaries. Tissue deposition of antibodies or immune complexes induces inflammation and subsequent injury of multiple organs and finally results in clinical manifestations of SLE, including glomerulonephritis, dermatitis, thrombosis, vasculitis, seizures, and arthritis. Evidence strongly suggests the involvement of genetic components in SLE susceptibility (summary by Oishi et al., 2008). Genetic Heterogeneity of Systemic Lupus Erythematosus An autosomal recessive form of systemic lupus erythematosus (SLEB16; 614420) is caused by mutation in the DNASE1L3 gene (602244) on chromosome 3p14.3. An X-linked dominant form of SLE (SLEB17; 301080) is caused by heterozygous mutation in the TLR7 gene (300365) on chromosome Xp22. See MAPPING and MOLECULAR GENETICS sections for a discussion of genetic heterogeneity of susceptibility to SLE.

Inflammation of the tonsils that has occurred repeatedly. The definition of recurrent may vary somewhat, but the criteria used recently as a measure of severity were five or more episodes of true tonsillitis per year, symptoms recurring for at least a year, and episodes that are disabling and that prevent normal functioning. In some cases recurrent tonsillitis may be related to immunosusceptibility. Evidence exists for a genetic predisposition for recurrent tonsillitis.

Concentration of the complement component C3 in the blood circulation below the lower limit of normal.

Increased susceptibility to bacterial infections, as manifested by recurrent episodes of bacterial infection.

Periodic (episodic or recurrent) bouts of fever.