Non-neoplastic diseases of the gallbladder

Follicular Cholecystitis: Reappraisal of Incidence, Definition, and Clinicopathologic Associations in an Analysis of 2550 Cholecystectomies

CONTEXT.

Follicular cholecystitis (FC) is a poorly characterized entity.

OBJECTIVE.

To determine its frequency/clinicopathologic associations.

DESIGN.

A total of 2550 cholecystectomy specimens were examined. Two hundred three of these were consecutive routine cholecystectomies submitted entirely for microscopic examination to determine the relative frequency of incidental pathologies in gallbladders (GBs). The remainder had representative sampling. Underlying conditions were nonobstructive pathologies (1270 nonspecific cholecystitis), obstructive (62 distal biliary tract tumors, 35 primary sclerosing cholangitis, and 31 autoimmune pancreatitis), and neoplastic (n = 949). FC was defined as 3 distinct lymphoid follicles (LFs)/centimeter.

RESULTS.

In the GBs totally submitted for microscopic examination, the true frequency of FC was found to be 2.5% (5/203), and in the representatively sampled group, it was 1.9%, with similar frequencies in nonobstructive, obstructive, and neoplastic cases (2.3%, 3.1%, and 1.3%, respectively, P = .77). When the 39 FC in nonneoplastic GBs contrasted with ordinary chronic cholecystitis, they were associated with older age (68 vs 49 years, P < .0001), similar gallstone frequency (68 vs 81%), female/male ratio (2.7 vs 2.6), and wall thickness (4 mm for both). None had lymphoma/parasites/Salmonella infection. Of 17 cases who had undergone gastric biopsy, 5 had chronic gastritis (2 with Helicobacter pylori). Microscopically, the LFs were the main inflammatory process often with minimal intervening inflammation. IgG4-positive plasma cell density was low (<10/high-power field) in 21/24(87.5%) cases.

CONCLUSIONS.

Follicular cholecystitis is seen in 2% of cholecystectomies, typically in significantly older patients, suggesting a deranged immune response. A third of the patients reveal biopsy-proven gastritis. FC does not seem to be associated with autoimmunity, lymphoma, or obstructive pathologies.

The Cumulative Risk Assessment of Hepatotoxic Chemicals: A Hepatic Histopathology Perspective

The increased concern on the consequence of exposure to multiple chemical combinations has led national regulatory authorities to develop different concepts to conduct risk assessments on chemical mixtures. Pesticide residues were identified as "problem formulation" in the respective European regulations and in this context, the European Food and Safety Authority has suggested to group pesticidal active ingredients (AIs) into cumulative assessment groups (CAGs) based on the toxicological properties of each AI. One proposed CAG, on the liver, currently consists of 15 subgroups, each representing a specific hepatotoxic effect observed in toxicity studies. Dietary cumulative risk assessments would then have to be conducted assuming dose additivity of all members of each CAG subgroup. The purpose of this publication is to group AIs based upon the knowledge of the pathogenesis of liver effects to discriminate between primary end points (direct consequence of chemical interaction with a biological target) and secondary end points (which are a consequence of, or that arise out of, a previous pathological change). Focusing on the relevant primary end points strengthens and simplifies the selection of compounds for cumulative risk assessment regarding the liver and better rationalizes the basis for chemical grouping. Relevant dose additivity is to be expected at the level of the primary/leading pathological end points and not at the level of the secondary end points. We recognize, however, that special consideration is needed for substances provoking neoplasia, and this category is included in the group of primary end points for which chemicals inducing them are grouped for risk assessment. Using the pathological basis for defining the respective CAGs, 6 liver subgroups and 2 gallbladder/bile duct groups are proposed. This approach simplifies the cumulative assessment calculation without obviously affecting consumer safety.