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Alkaptonuria, an autosomal recessive metabolic disorder due to deficiency of the enzyme homogentisate dioxygenase[1] results in deposit of oxidized deposits of homogentisic acid with special affinity for cartilage, joints and soft tissue[2,3] giving them an ochre or yellow hue grossly as well as histologically.[4] Virchow, who histologically described the connective tissue in alkaptonuria, coined the word ochronosis.[5]

We present here the first case in world literature to illustrate the coexistence of ochronosis and renal cell carcinoma in a 53-year-old female who presented with the complaints of recurrent hematuria, dysuria and hypertension since 1-year but totally asymptomatic of ochronosis. Radiology of the abdominal mass palpable in the right iliac fossa showed a tumor mass measuring 16 cm × 10 cm in the lower pole of the right kidney. A radical nephrectomy was performed, and the right 9th and 10th rib were resected as they were coal black in color[Figure 1a and b]. The renal mass showed features of a unifocal clear cell carcinoma[Figure 2a], Fuhrman nuclear grade II, stage T2N0M0. The adjacent normal renal parenchyma showed pigment deposits in the tubules[Figure 2a] inset. The bone fragments showed diffuse brown discoloration of the bone matrix, osteocytes with a few deposits in soft tissue[Figure 2b].