Fluoresan İn Situ Hibridizasyon (FISH) Yöntemi ile Saptanan Yüksek Oranda Çoklu Kandidemi: Klinik ve Prognostik Anlamı Nedir?

Abstract

Objective: The fluorescence in situ hybridization (FISH) with rRNA-targeted probes is a molecular method that allows identification of microorganisms in mixed assemblages from direct clinical samples without cultivitation. The aim of this study was to investigate the clinical features and risk factors in patients with single and multiple-species candidemia detected with FISH method and also to evaluate the episodes of breakthrough candidemia. Material and Methods: A total of 325 positive blood culture samples were examined between January and August 2004 in medical microbiology laboratory of Mersin University Hospital. The demographic and clinical data of 45 patients with candidemia detected with conventional culture methods, FISH and PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) were analyzed retrospectively, single and multiple-species candidemia were investigated among patients with candidemia and these patients were compared with respect to risk factors. Results: Thirty five (77.8%) of 45 patients with candidemia had a single Candida species and 10 (22.2%) had multiple-species detected by FISH method. Of these 45 cases, 31.1% had associated solid and hematologic malignancies. The mean duration of hospitalization was 27 (2-180) days. All patients had at least one indwelling catheter (urinary catheter: 80%, peripheric venous catheter: 55.6%, central venous catheter: 26.7%). Most of the patients (95.6%) had been treated with broad spectrum antibiotics. The candidemias were mostly caused by non-albicans Candida spp., particularly Candida parapsilosis (71.1%). The rate of breakthrough candidemia was detected in 11.1% of the patients with candidemia and all of these were in patients with single species candidemia. Surprisingly, in case of single-species candidemia, the mortality rate (77.8%) was higher than that of multiple-species candidemia (22.2%). Conclusion: According to our data, the indwelling catheters and treatment with multiple antibiotics were considered as the risk factors for single and multiple-species candidemia. Although the rate of multiple-species candidemia detected with FISH method was found to be high, clinical and prognostic significance of multiple-species candidemia are still debatable.