RENAL LESIONS IN SCLERODERMA : CLINICAL AND PATHOLOGICAL FEATURES

SUMMARY The significant renal lesion in scleroderma is a mucoid or loose fibrous swelling of the walls of the intralobular arteries involving the entire wall or the intima alone without inflammatory cell reaction ; the lumen is substantially narrowed or obliterated. Interference with cortical blood flow leads to necrosis and thrombosis of the afferent arterioles and focal infarcts of the cortex. Clinically, these changes are mirrored by rapidly progressive renal failure or by severe hypertension or both. Duration of the illness is short. Lesions in other organs are infrequent and relatively mild. The clinical features and the renal lesions closely resemble those described in malignant or rapidly progressive hypertension. Cortico‐steroids accelerate the progress of the hypertension or may even determine its appearance. Thickening of the basement membranes of the glomerular capillaries is found independently of these arterial lesions. The histories of patients showing this glomerular change suggest that it is probably related clinically to the occurrence of a trace of albumin in the urine, and that the appearance of albuminuria does not necessarily presage the onset of severe hypertension and renal failure.