New features of invasive candidiasis in humans: amyloid formation by fungi and deposition of serum amyloid P component by the host.

BACKGROUND: Invasive candidiasis occurs in the gastrointestinal tract, especially in neutropenic patients. We were interested in determining whether invasive fungi formed amyloid in humans as they are known to do in vitro. We also sought to characterize the consequence(s) of such amyloid formation. METHODS: Tissue from 25 autopsy patients with invasive candidiasis of the gastrointestinal tract was stained with amyloidophilic dyes and for the presence of serum amyloid P component (SAP). Confirmation of the interaction of SAP and Candida was demonstrated using Candida albicans and mutants for amyloid formation. RESULTS: Amyloid was present on the cellular surface of fungi invading gut tissue. Moreover, SAP bound to the fungal cell walls, confirming the presence of amyloid. In vitro observations showed SAP bound avidly to fungi when amyloid formed in fungal cell walls. An unexpected result was the lack of host neutrophils in response to the invading fungi, not only in neutropenic patients but also in patients with normal or increased white blood counts. CONCLUSIONS: We report the first demonstration of functional fungal amyloid in human tissue and the binding of SAP to invading fungi. It is postulated that fungal amyloid, SAP, or a complex of the proteins may inhibit the neutrophil response.

Endoscopic ultrasound with biopsy of omental mass for cholangiocarcinoma diagnosis in cirrhosis.

In this report, a patient had a previous diagnosis of cholangiocarcinoma with an extended cholecystectomy. Three years later, he was evaluated for recurrent ascites. The patient had several large volume paracentesis, without evidence of malignant cells. Subsequently, endoscopic ultrasound (EUS) with fine needle aspiration (FNA) of both lymph and omental nodules was utilized. While the lymph nodes were negative for malignancy, the omental nodule was interrogated with multiple antibodies and was found to be positive for neoplasia. EUS with FNA can safely be used in patients with cirrhosis to spare the patient invasive evaluation such as exploratory laparotomy (ex-lap) for diagnosis and staging of cholangiocarcinoma.

Postmortem candidaemia: marker of disseminated disease.

AIM: The significance of finding Candida species in heart blood cultures obtained at postmortem examination has never been studied. This article describes the findings of autopsy patients with postmortem candidaemia and it compares them with findings in autopsy patients with antemortem candidaemia. METHOD: 23 patients with Candida species isolated from heart blood at autopsy were identified over a 10-year period. These patients were compared with 10 autopsy patients found during the same time period with antemortem blood cultures isolating Candida species, but not positive postmortem heart blood cultures. Antemortem and postmortem records were reviewed. RESULTS: All 23 patients with Candida species isolated from postmortem blood culture had one or more antemortem risk factors for disseminated candidiasis, such as positive antemortem blood cultures, isolation of Candida from sterile internal sites, neutropenia, recent abdominal surgery, broad-spectrum antibiotic administration or the use of central venous catheters or other invasive devices. Eight patients showed histological proof of invasive candidiasis in addition to the positive heart blood cultures. This group did not differ with respect to risk factors from 10 autopsy patients with disseminated candidiasis and antemortem blood cultures with Candida species. However, all the patients with antemortem candidaemia had histological evidence of disseminated candidiasis at autopsy. CONCLUSION: Candidaemia, when documented by heart blood culture performed at autopsy or by antemortem blood culture, is an insensitive, but highly specific, indicator of disseminated candidiasis.