Renal disease-a sixth cardinal feature of the Laurence-Moon-Biedl syndrome.

A 39 year old man with 4 of the 5 cardinal features of the Laurence-Moon-Biedl syndrome (LMBS) had proteinuria and moderate renal failure. Excretory urography showed small cysts communicating with the dilated calyceal system. Renal biopsy showed diffuse mesangial sclerosis and cellular proliferation. Excretory urograms in 22 of 24 reported patients demonstrated similar findings. Review of renal pathology reports on 16 patients revealed either chronic glomerulonephritis or severe tubulo-interstitial disease with cysts or both in 8 of 9 who died from uremia and 2 of 7 who died from other causes. The abnormalities seen on excretory urography occur more frequently than 2 of the cardinal features, and as uremia is often the cause of death for these patients, renal disease should be considered a cardinal feature of LMBS.