[Nail-patella syndrome associated with monoclonal gammopathy. Review regarding a case].

A 54 years old female with significant impairment of renal function is presented. On physical examination, the presence of dystrophic nails, elbow dysplasia and prominent iliac horns. Familial study showed similar nail and bone deformities in 3 of six sons. The nail patella syndrome diagnosis was based on these findings. This is a rare autosomal dominant hereditary disease, probably related to congenital alterations in collagen metabolism. Clinical characteristics include bone abnormalities that principally involve knees and elbows, nail alterations and the presence of iliac horns, that are considered pathognomonic of the syndrome. Renal involvement is observed in 30 to 55% of cases. This patient had also an IgA-lambda paraprotein, whose relationship to the above mentioned syndrome is uncertain, since no evidences of malignant plasma cell dyscrasia were demonstrated.