Acute renal failure with hypocreatininemia in Guillain-Barré syndrome.

A 68-year-old woman with Guillain-Barré syndrome had profoundly depressed serum creatinine concentration and 24-hour urinary creatinine excretion despite maintenance of her weight by hyperalimentation. Because of hypocreatininemia, the development of aminoglycoside-induced acute renal failure was initially missed. A retrospective study of seven patients with Guillain-Barré syndrome who were treated with hyperalimentation to maintain nutritional status showed a significant decrease in serum creatinine concentration but no significant decline in weight or blood urea nitrogen level. Because the serum creatinine is decreased in patients with Guillain-Barré syndrome, caution must be exercised in using serum creatinine determination as an estimate of glomerular filtration rate.