||It has been suggested that this article be merged into Diseases of the biliary tree. (Discuss) Proposed since December 2013.|
|Classification and external resources|
Gallbladder diseases are diseases involving the gallbladder.
Gallstones may develop in the gallbladder as well as elsewhere in the biliary tract. If gallstones in the gallbladder are symptomatic, surgical removal of the gallbladder, known as cholecystectomy may be indicated.
Gallstones form when the tenuous balance of solubility of biliary lipids tips in favor of precipitation of cholesterol, unconjugated bilirubin, or bacterial degradation products of biliary lipids. For cholesterol gallstones, metabolic alterations in hepatic cholesterol secretion combine with changes in gallbladder motility and intestinal bacterial degradation of bile salts to destabilize cholesterol carriers in bile and produce cholesterol crystals. For black pigment gallstones, changes in heme metabolism or bilirubin absorption lead to increased bilirubin concentrations and precipitation of calcium bilirubinate. In contrast, mechanical obstruction of the biliary tract is the major factor leading to bacterial degradation and precipitation of biliary lipids in brown pigment stones.
Xanthogranulomatous cholecystitis (XGC) is a rare form of gallbladder disease which mimics gallbladder cancer although it is not cancerous. It was first discovered and reported in the medical literature in 1976 by J.J. McCoy, Jr., and colleagues.
Gallbladder Disease During Pregnancy
During pregnancy when female sex hormones are endogenously raised, biliary sludge (particulate material that is composed of cholesterol, calcium bilirubinate, and mucin) appears in 5% to 30% of women. Resolution frequently transpires during the post-partum period: sludge disappears in two-thirds; small (<1 cm) gallstones (microlithiasis) vanish in one-third, but definitive gallstones become established in ~5%. Additional risk factors for stone formation during pregnancy include obesity (prior to the pregnancy), reduced high density lipoprotein (HDL) cholesterol and the metabolic syndrome.
Links to Hormonal, Orally Administered Contraceptives
The female sex has a most compelling association with gallstone disease, especially during the fertile years. Women are almost twice as likely as men to form stones; the gap narrows following menopause after which men begin to catch up. The underlying mechanism is female sex hormones; parity, oral contraceptive use and estrogen replacement therapy are established risk factors for cholesterol gallstone formation. Female sex hormones adversely influence hepatic bile secretion and gallbladder function. Estrogens increase cholesterol secretion and diminish bile salt secretion, while progestins act by reducing bile salt secretion and impairing gallbladder emptying leading to stasis. A new 4th generation progestin, drospirenone, used in some oral contraceptives may further heighten the risk of gallstone disease and cholecystectomy; however, the increased risk is quite modest and not likely to be clinically meaningful.
A retrospective (historical) cohort study was performed on a very large data base including 1980 and 1981 Medicaid billing data from the states of Michigan and Minnesota in which 138,943 users of OCs were compared with 341,478 nonusers. Oral contraceptives were shown as risk factors for gallbladder disease, although the risk is of sufficient magnitude to be of potential clinical importance only in young women.
The 1984 Royal College of General Practitioners' Oral Contraception Study suggests that, in the long-term, oral contraceptives are not associated with any increased risk of gallbladder disease, although there is an acceleration of the disease in those women susceptible to it.
Newer research suggests otherwise. A 1993 meta-analysis concludes that oral contraceptive use is associated with a slightly and transiently increased rate of gallbladder disease, but laters confirms that modern low-dose oral contraceptives are safer than older formulas, though an effect cannot be excluded.
A 2001 comparative study of the IMS LifeLink Health Plan Claims Database interpreted that in a large cohort of women using oral contraceptives, there was found a small, statistically significant increase in the risk of gallbladder disease associated with desogestrel, drospirenone and norethindrone compared with levonorgestre. No statistically significant increase in risk was associated with the other formulations of oral contraceptive (ethynodiol diacetate, norgestrel and norgestimate).
Other Risk Factors
A prospective study in 1994 noted that body mass index remains the strongest predictor of symptomatic gallstones among young women, and included number of pregnancies over four, weight gain, and cigarette smoke as additional risk factors. Alcohol was shown to have an inverse relationship between use and gallbladder disease.
- Makino, Isamu; Yamaguchi, T; Sato, N; Yasui, T; Kita, I (2009). "Xanthogranulomatous cholecystitis mimicking gallbladder carcinoma with a false-positive result on fluorodeoxyglucose PET". World Journal of Gastroenterology 15 (29): 3691–3. doi:10.3748/wjg.15.3691. PMC 2721248. PMID 19653352.
- Rao, RV; Kumar, A; Sikora, SS; Saxena, R; Kapoor, VK (2005). "Xanthogranulomatous cholecystitis: Differentiation from associated gall bladder carcinoma". Tropical Gastroenterology 26 (1): 31–3. PMID 15974235.
- McCoy Jr, JJ; Vila, R; Petrossian, G; McCall, RA; Reddy, KS (1976). "Xanthogranulomatous cholecystitis. Report of two cases". Journal of the South Carolina Medical Association 72 (3): 78–9. PMID 1063276.