Dissecting aneurysms of the aorta, and pancreatic islet cell hyperplasia with diabetes in corticosteroid- and chlorothiazid- treated hamsters

Acute enlargement and subsequent rupture of an abdominal aortic aneurysm in a patient receiving chemotherapy for pancreatic carcinoma

We report a case of ruptured abdominal aortic aneurysm (AAA) in a patient receiving chemotherapy for pancreatic cancer. We reviewed the literature on the effects of corticosteroids and chemotherapy on aaa formation and discuss possible mechanisms for drug action to promote aneurysm expansion and rupture. If cancer and AAA coincide and curative chemotherapy is possible, a potential impact of chemotherapy on AAA expansion should be considered.

Diagnosis and management of 17 consecutive patients with inflammatory abdominal aortic aneurysm

This report reviews the authors' experience in diagnosing and managing 17 consecutive patients with inflammatory abdominal aortic aneurysm (AAA). Among 491 patients undergoing repair for AAA during a 10-year period, 17 (3%) had evidence of associated periaortic fibrosis, which was confirmed histologically. No patient had acute rupture, and two patients (12%) had chronic contained rupture. Ureteral obstruction was evident in seven patients. In 41% of the patients, available surgical correlation demonstrated that computed tomographic (CT) scan accurately delineated the extent of the disease. Sixteen patients underwent aneurysm resection. Ureteral obstruction was relieved by ureterolysis in three patients treated early in this series. In the last period of the study, well-documented hydronephrosis spontaneously subsided in two patients without special treatment. Of these 17 patients, 15 (88%) were early (30-day) survivors. There were two late deaths at 2 months and 5 years; 12 (71%) patients are still alive and free of symptoms up to 10 years after operation. On the basis of our study, we conclude the following: (1) precise preoperative diagnosis and detailed anatomic information are widely available with CT; (2) aneurysm resection is the treatment of choice because the risk of rupture still exists, and this procedure seems to reverse the inflammatory process; (3) good early and late results can be expected with proper surgical technique; and (4) routine follow-up with CT is recommended to document resolution or progression of the fibrotic process after aneurysm resection.

Cortisone-induced islet cell hyperplasia in hamsters

Pancreatic islet cell hyperplasia was studied in hamsters during one to eight weeks of cortisone treatment. Measurement of serum glucose and insulin; pancreatic insulin, glucagon, somatostatin, pancreatic polypeptide as well as islet tissue morphometry were performed. Serum glucose was highest at week 2, followed by mild to moderate hyperglycemia. Serum insulin was increasingly higher from week 1 to week 8. Pancreatic insulin was maximal at week 5 then declined through week 8 in the presence of beta cell neurosis in markedly hyperplastic islets. Pancreatic concentration of somatostatin and pancreatic polypeptide moderately increased more than the control levels; however, compared with the controls, glucagon was reduced by cortisone treatment. Effect of cortisone in the four types of islet cells is discussed, particularly on beta cell hyperplasia, which appears to be a response to decreased insulin binding to the target organs with no changes in receptor concentration.

Immunosuppression and toxoplasmic encephalitis: clinical and experimental aspects

Encephalitis developing after prolonged antineoplastic therapy in two patients with Hodgkin's disease and in one with multiple myeloma was found at autopsy to be caused by toxoplasmosis. To better understand the pathogenesis of the brain lesions, ranging from microscopic foci to some having a diameter of 6 cm. and characterized by proliferation of the organisms at the margins of expanding necrosis, an animal model was studied. Similar lesions were produced in hamsters by inducing relapse of chronic latent toxoplasmosis through administration of cortisone, cyclophosphamide, or whole body irradiation, but toxic doses of nitrogen mustard and urethane did not precipitate relapse. Notably, relapsing toxoplasmosis generally involves the brain exclusively, suggesting a special susceptibility related to immune mechanisms. The roles of cells and of antibodies in immune surveillance against this chronic infection in otherwise normal hosts are considered. In man the suppression of cellular immunities by certain antineoplastic agents would seem to be decisive in causing relapse of toxoplasmosis, rather than the replacement of immunologically active cells by neoplasm. Because the infection can be controlled with sulfadiazine and pyrimethamine, a high index of suspicion is essential to detect incipient cerebral toxoplasmosis. serial serologic testing is helpful by demonstrating titer elevations; however, poor antibody production or transferred antibody may be misleading clinically when single tests are evaluated. Similarly, a poor inflammatory cell response can make it difficult for the histopathologist to detect small lesions in these patients.