Acanthamoeba spp. and Balamuthia mandrillaris leading to fatal granulomatous amebic encephalitis.

Acanthamoeba spp. and Balamuthia mandrillaris are free-living amebae known to cause disseminated and fatal central nervous system dysfunction which manifests as granulomatous amebic encephalitis (GAE) with exceedingly rare frequency. We report two lethal cases of infection with free-living amebae: an acute case of Acanthamoeba spp. infection in an immunocompromised female and a subacute case of B. mandrillaris in a Hispanic male. The Acanthamoeba spp. infection presented with an atypical lesion in the thalamus that caused rapid deterioration of the patient while the case of B. mandrillaris had a prolonged clinical course with multifocal lesions beginning in the frontal lobe. Cerebrospinal fluid results were non-specific in both cases, however, post-mortem histology demonstrated the presence of trophozoites along a perivascular distribution of necrosis and infiltrate composed primarily of neutrophils. In addition to detailing the clinical presentations of these infrequent amebic infections, we offer insight into the difficulties surrounding their diagnoses in order to aid the clinician in accurate and timely identification.

Management of periampullary adenocarcinoma by pancreaticoduodenectomy at a regional teaching hospital.

BACKGROUND: Periampullary adenocarcinoma (PA) includes: pancreatic, duodenal and ampullary adenocarcinoma; and cholangiocarcinoma. Pancreaticoduodenectomy (PD) is required for cure of PA. Previous studies demonstrated the likelihood of cure increases when a microscopically negative (R0) margin is achieved. Clearance of the superior mesenteric artery (SMA) margin has been identified as the most critical margin in PD. Some authors have emphasized the importance of certain techniques to clear the SMA margin. Neither the degree to which these techniques have been incorporated nor their impact on margin status and survival has been described. We hypothesized that use of techniques focusing on clearing the SMA margin would result in higher R0 resection rates and improved survival after PD in patients with PA. METHODS: A retrospective study was performed on patients from 1/1/1985 until 7/31/2007. Data on patient demographics, clinical presentation, preoperative treatment, operative technique, margins, and postoperative outcomes were collected. Ninety-three patients were identified for inclusion in the study. Three approximately equal groups were created for analysis. RESULTS: The overall survival (OS) for the entire cohort was 19 months and was not different among the groups studied. Margins were microscopically negative in 81% of cases. The percentage of node-positive cases increased during the time period, as did the number of lymph nodes (LNs) examined (P=0.017). The use of pylorus-preserving PD decreased (P=0.001) while resection of the superior mesenteric/portal vein (SMV/PV) increased during the study period. We observed an increase in descriptions of the clearance of the anterior aspect of the aorta and inferior vena cava (IVC), dissection to the right side of the SMA, dissection to the origin of the SMA and intra-operative identification of the SMA margin. Dissecting to the SMA did not change the likelihood of achieving an R0 margin. OS was improved after R0 resections (R0: 21 months vs. R1/2: 10 months) but this difference was not statistically significant (P=0.099). There was no association between margin status and OS. Changes in the pathology reporting of margins were observed, with statistically significant increases in the percentage of cases in which the SMA, common bile duct and pancreatic neck margins were separately reported. However, the SMA margin was separately reported in only 26% of pathology reports. CONCLUSIONS: The operative techniques used in PD at this institution have changed over time. The increasing frequency of dissection to the SMA and identification of the SMA margin by both surgeon and pathologist suggest an increased attention to the SMA margin. This shift did not result in significant improvements in survival or margin status, but it is consistent with the recognition of the importance of the SMA margin. Our analysis has also identified areas of potential improvement in the ways in which operative and pathology reports for PD are generated.