[Mixed type amyloidomas, beta2 microglobulin and AL lambda, in a long term hemodialysis patient]. / Amyloïdomes fessiers de type mixte, beta 2-microglobuline et AL lambda, chez une patiente hémodialysée au long cours.

A frequent complication of hemodialysis is deposition of beta 2-microglobulin amyloid in tendons and joints. Soft tissues involvement is exceptional. A 74 year-old woman on hemodialysis for 21 years developed two bilateral and symmetric tumours in gluteal regions causing discomfort when sitting. Histology, immunohistochemistry and electron microscopy showed that deposit consisted of predominant beta 2-microglobulin and lambda light chain. This is an unusual localisation of amyloidosis developing late in the course of hemodialysis. It may be perhaps initiated by chronic traumatism and be promoted by the light chain lambda of immunoglobulin.

[Alveolar rhabdomyosarcoma: apropos of a rare location]. / Rhabdomyosarcome alvéolaire: à propos d'une localisation exceptionnelle.

Rhabdomyosarcoma is a soft tissue tumor of striated muscle origin. It is observed mainly in children and adolescents. Rhabdomyosarcoma predominantly occurs in three regions: head and neck, genito-urinary tract and retroperitoneum, and upper and lower extremities. We report a case of primary alveolar rhabdomyosarcoma of the mesentery occurring in a 68-year-old man. Rhabdomyosarcomas can be diagnosed on microscopic findings and immunohistochemical features. Cytogenetic findings can be helpful in the diagnosis.

[Cholesterol embolism: unusual cause of small intestine occlusion]. / Embolie de cholestérol: une cause rare d'occlusion de l'intestin grêle.

We describe a case of small bowel obstruction secondary to cholesterol crystal embolism in a 83-year-old man. Clinical symptoms were dominated by weight loss and vomiting. Small bowel barrium X-ray displayed a short and unique stricture of the jejunum. Atheromatous embolism was suspected in the presence of an aortic aneurysm. At laparotomy, a 2 cm stricture of jejunum was identified and a 6 cm length segment of small bowel was resected. Pathological features were consistent with cholesterol crystal embolism. The patient did well 3 months after surgery. This observation points out the nonspecific clinical presentation of gastrointestinal cholesterol embolism.

Use of immunoblot assay to define serum antibody patterns associated with Helicobacter pylori infection and with H. pylori-related ulcers.

Serology has been used worldwide to detect Helicobacter pylori infection. Using an immunoblot assay with an antigen from strain ATCC 43579, we sought to determine the antibodies which were good markers of colonization and the antibody patterns associated with ulcers or atrophy. Out of 98 dyspeptic patients, 41 were colonized by H. pylori, based on a positive culture or on positive results of both a urease test and direct examination. These 41 patients were seropositive by an enzyme immunoassay, and 12 of them had ulcers and 29 had evidence of atrophy. Fifty-seven of the 98 patients were noncolonized. Twenty-five of the 57 had evidence of gastric atrophy, and 10 were seropositive; 5 of these 10 had ulcers. By Western blot analysis, 12 antibodies were significantly more frequent in sera from colonized patients, and they produced immunoreactive bands at 125, 87, 74, 66, 54, 48, 46, 42, 35, 30, 16 and 14 kDa. The presence of at least one band at 54, 35, or 42 kDa was the best marker of infection (sensitivity, 95%; specificity, 82%). In the group of colonized patients, none of the antibody patterns were correlated to gastric atrophy. Conversely, the presence of a band at 125, 87, or 35 kDa was statistically associated with the presence of an ulcer. The simultaneous presence of bands at 87 and 35 kDa predicted the risk of ulcers with 83% sensitivity and 69% specificity. By using CagA-positive and VacA-positive strains and CagA-negative and VacA-negative isogenic mutants, the antigens corresponding to the bands at 125 and 87 kDa were shown to be CagA and VacA, respectively. On the other hand, the 35-kDa antigen is a novel uncharacterized component of H. pylori. These results may help to optimize the composition of antigenic preparations for serologic detection of H. pylori colonization. Immunoblot assay would be useful for screening patients at high risk of ulcers.