Calcium bilirubinate stones

As is often the case for biological products, the term pure is a misnomer no stones are made of pure cholesterol or concentric layers of pure cholesterol and calcium bilirubinate. Stones often contain other components such as iron, proteins, and mucopolysaccharides. In fact, even the purest cholesterol stones seem to contain small amounts of protein or polysaccharide at their center, a finding that is in keeping with the concept that gallstones, like kidney... 

Examples of secretions appear in bile (Sato, 1962 Matsushiro, 1963) Tenhunen, 1965) and intestinal juice (Karunairatnum and Levvy, 1951 and sometimes in salivary secretions (Yamanaka et al., 1965 Murata and Miyaji, 1966 Harvey et at., 1966). Judging from its properties, e.g., pH, -glucuronidase activity in these fluids is probably due in part to bacterial infection. /S-G ueuronidase in bile probably plays some role in the entero-hepatic circulation of drugs (Williams el al., 1965) and hormones (Paschkis and llakoff, 1950 Knapstein et cU., 1966, 1967), and also may induce the formation of calcium bilirubinate stones (Maki el al., 1962 Saito, 1964 Sato el al., 1964 Maki, 1966). 

The mechanism of calcium bilirubinate stone formation by bacterial jS-glucuronidase has been proposed by iUaki et al. (Maki, 1966 Haki and Sato, 1966) as follows the enzyme hydrolyzes bilirubin glucuronide to yield free glucuronic acid and bilirubin, and calcium in bile at the carboxyl radical of liberated bilirubin forms calcium bilirubinate stone. 

Biliary sludge A deposit of tiny stones or crystals made up of cholesterol, calcium bilirubinate, and other calcium salts. The cholesterol and calcium bilirubinate crystals in biliary sludge can lead to gallstone formation. 

Recent advances in infrared spectroscopy have allowed rapid and simple determination of some gallstone ingredients (Chihara et al., 1958) with a minimum quantity of specimen. Of various absorptions characteristic of calcium bilirubinate, the one at 1624 cm , which is due to Vc c of pyrrole nuclei (Suzuki and Toyoda, 1966), was chosen as the key band for quantitative analysis. In analyses of 10 gallstone specimens (Toyoda, 1966) the infrared-determined calcium bilirubinate content was found to lie in between values from two kinds of chemical data those obtained for extracts of the stones with (a) chloroform after HCl treatment, plus a 5 % ammonia extraction, and (b) those obtained for extracts with chloroform, but no ammonia extraction. Toyoda claims that the infrared data show satisfactory proportionality with both types of data. 

Calcium has been recognized as a constituent of gallstones since the earliest chemical studies (see reference 118). It occurs as calcium carbonate (either calcite or aragonite), calcium phosphate (apatite), calcium bilirubinate, or the salts of bile acids and fatty acids. In normal hepatic bile, the calcium concentration is about 21 mg %. It is about 45 mg % in normal gallbladder bile and about twice that in the gallbladder bile of patients with cholesterol stones (119). The concentration of calcium is said to vary with the concentration of bile salts (3). Apparently, calcium in bile is bound in part to bile salt micelles, and under normal conditions this complex remains stable and soluble (120). However, under appropriate conditions of pH, calcium concentration, and anion concentration, calcium salts may precipitate. 

Usuki (169) raised rabbits on a diet deficient in fat-soluble vitamins and found a 9% incidence of gallstones after 6-8 weeks. Qualitative analysis revealed that these small sandlike stones contained calcium, bilirubin, and traces of cholesterol. 

Constituents of human gall stones are cholesterol and calcium bilirubinate. 

Grossly, there are two major types of gallstones pure cholesterol or cholesterol hydrate stones and mixed stones. The first type are yellowish, friable, and primarily composed of radiating cholesterol crystals. The mixed stones include various calcium salts such as carbonates, bilirubinates, and phosphates. Often the major components, cholesterol and pigmented salt, are arranged in successive, concentric layers. An example of gallstone is shown in Fig. 9-19. 

The pathogenesis of gallstones can essentially be reduced to a matter of solubility of the various solutes that constitute the stone—cholesterol in cholesterol stones and cholesterol, calcium carbonate, phosphate, or bilirubinate in mixed stones. 

This is a stone which may be formed in secreting organs or their ducts. They have been found in the salivary gland, pancreas and prostate but are most frequently encountered in the urinary tract and gall bladder. Urinary calculi usually consist of calcium, magnesium, oxalate, carbonate or phosphate but occasionally uric acid, cystine and xanthine stones occur as a result of a metabolic disease. Cholesterol and bilirubin are found in biliary stones. 

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