Clinical features of atypical gout:
(1) It occurs in elderly patients > 60 years of age.
(2) The onset is often insidious.
(3) Chronic polyarthritis is common.
(4) Tophi are frequent at presentation. These may occur as microtophi in the finger pads or over Heberden nodes in patients with concurrent osteoarthritis.
(5) Acute flare ups may be misdiagnosed as cellulitis or septic arthritis, but patients may also develop septic arthritis.
(6) Many patients have a history of diuretic therapy.
(7) Many patients have a mild decrease in renal function.
Diagnosis depends on demonstration of sodium urate monohydrate crystals in an aspirate from a joint or tophus.
Additional features:
(1) It affects both men and women.
(2) The arthritis may be symmetric or asymmetric.
(3) The serum urate may or may not be elevated.
(4) It may involve any joint in the upper and/or lower extremity.
(5) A small percentage of patients have a family history of gout.
(6) Patients may be misdiagnosed as having osteoarthritis or rheumatoid arthritis, or it may occur together with osteoarthritis or rheumatoid arthritis.
