A disorder of uric acid crystals deposition in joints
Primary Gout (90% of cases)
Enzyme defects unknown (85%–90% of primary gout): Overproduction of uric acid
Underexcretion of uric acid with normal production
Secondary Gout (10% of cases)
Associated with increased nucleic acid turnover—e.g., leukemias and tumor lysis syndrome
Chronic renal disease: Reduced excretion of uric acid
Inborn errors of metabolism—e.g., complete HGPRT
Hypoxanthine-guanine phosphoribosyltransferase deficiency (Lesch-Nyhan syndrome).