[Gallbladder sludge: a sonographically recognizable stage of lithogenesis].

The appearance and the natural course of gallbladder sludge were studied by ultrasonography in 82 patients. Sludge was found in conditions with a functional or organic disturbance of gallbladder emptying: alcoholic cirrhosis and an atonic gallbladder in the fasting state, e.g., extrahepatic ductal obstruction and obstruction of the cystic duct. No clinical complaints could be attributed to sludge. After the normal bile flow had re-established the sludge disappeared in many cases. In 9 of 82 sludge-positive patients (10,9 per cent) ultrasonography revealed gallstone formation. Newly-formed stones obtained from 2 patients had the aspect of pigment stones and were analyzed by infrared spectroscopy. They consisted of calcium bilirubinate. This material constitutes the pigment granules which are suspended in the sludge. It was concluded that sludge was an early phase of stone formation. Alcoholic cirrhosis, obstruction of the biliary tract, gastrectomy, celiac sprue and prolonged fasting may predispose to lithiasis secondary to the precipitation of sludge in a large, atonic or distended gallbladder. Ultrasonography is instrumental to detect an early state of gallstone formation in those patients who carry a risk.