tent forms with high crystallization rate in multiple cho-Besides classical plate-like cholesterol monohydrate lesterol stone patients. Tubules and spirals are transient crystals, a variety of crystal shapes have recently been forms that are associated with more extensive crystallidescribed in model biles but their relevance for human zation. Patients treated with ursodeoxycholate often gallstone formation is unknown. We therefore studied have atypical crystals in their fresh bile. (HEPATOLOGY crystallization behavior in gallbladder bile from choles-1996;23:738-748.) terol stone patients (54 untreated, 13 ursodeoxycholatetreated) and 6 pigment stone patients. Bile preparation by ultrafiltration or ultracentrifugation left biliary lipid composition unchanged but plates and their aggregates,
Nucleation of cholesterol crystals is a prerequisite for and arcs and needles crystallized more extensively while the formation of cholesterol gallstones. 1 Several studies spirals and tubules crystallized less extensively in ultrahave recently focused on factors that might contribute centrifuged bile than in ultrafiltered bile. Plates, aggreto cholesterol nucleation. An excess of nucleation progates, and arcs/needles were seen in 90%, 36%, and 18% moting proteins 2 or a shortage of nucleation inhibiting of the cases respectively of fresh unfiltered biles of unproteins 3 in bile has been suggested to be important. treated cholesterol stone patients, while spirals and tu-Patients with multiple cholesterol stones have faster bules were always absent. In ultrafiltered biles arcs/needles, plates and aggregates progressively developed as nucleation 4,5 and a higher risk of gallstone recurrence persistent forms. Spirals and tubules occurred tranafter successful nonsurgical therapy 6 than patients siently and were associated with increased deoxycholic with solitary cholesterol stones. This has been sugacid (/41%, P Γ
.039) and with more extensive cholesgested to relate to increased amount of nucleation proterol crystallization. Rate/extent of crystallization of all moting proteins in bile of patients with multiple crystal forms was higher (P Γ΅ .0001) for multiple than stones. 7 Other factors possibly involved in cholesterol solitary cholesterol stone patients. Ursodeoxycholategallstone formation include increased concentration of treated patients had atypical platelike cholesterol crysgallbladder bile, 4,8,9 greater biliary supersaturation of tals in fresh unfiltered biles that decreased in size at cholesterol, 4,10 impaired gallbladder emptying, [11][12][13] as prolonged observation and in 2 cases even dissolved well as an increased amount of more hydrophobic bile after 15 and 20 days. No crystals ever developed in ultrafiltered bile of ursodeoxycholic acid (UDCA)-treated pa-salts. 14,15 Conventionally, the crystal observation time tients during 21 days. Pigment stone patients seldom (previously referred to as nucleation time) is defined developed crystals. as the earliest time required for detection of classical Thus, plates, aggregates and arcs/needles are persisplatelike cholesterol monohydrate (rectangular, birefrangent, often notched) crystals in bile, as determined by daily microscopical examination of a drop of bile. A Abbreviations: CSI, cholesterol saturation index; UDCA, ursodeoxycholic short crystal observation time provides a better disacid.
crimination than cholesterol saturation index (CSI) be-
From the