Utility of PCR in diagnosis of invasive fungal infections: real-life data from a multicenter study.

Prospective studies addressing the clinical value of broad-range PCR using the internal transcribed spacer region (ITS) for diagnosis of microscopy-negative fungal infections in nonselected patient populations are lacking. We first assessed the diagnostic performance of ITS rRNA gene PCR compared with that of routine microscopic immunofluorescence examination. Second, we addressed prospectively the impact and clinical value of broad-range PCR for the diagnosis of infections using samples that tested negative by routine microscopy; the corresponding patients' data were evaluated by detailed medical record reviews. Results from 371 specimens showed a high concordance of >80% for broad-range PCR and routine conventional methods, indicating that the diagnostic performance of PCR for fungal infections is comparable to that of microscopy, which is currently considered part of the "gold standard." In this prospective study, 206 specimens with a negative result on routine microscopy were analyzed with PCR, and patients' clinical data were reviewed according to the criteria of the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group. We found that broad-range PCR showed a sensitivity, specificity, positive predictive value, and negative predictive value of 57.1%, 97.0%, 80%, and 91.7%, respectively, for microscopy-negative fungal infections. This study defines a possible helpful role of broad-range PCR for diagnosis of microscopy-negative fungal infections in conjunction with other tests.

Enterocolitis due to simultaneous infection with rotavirus and Clostridium difficile in adult and pediatric solid organ transplantation.

Diarrhea is a well-known complication of immunosuppression but is also frequently caused by pathogens such as Clostridium difficile (CD) and rotavirus (RV). Three adult and five pediatric solid organ recipients (SORs) developed diarrhea with simultaneous identification of CD and RV. Rotavirus was identified using an immunochromatografic- or enzyme-linked immunosorbent assay; CD was identified using a rapid immunoassay or enzyme immunoassay. One adult renal, one adult kidney-pancreas, one adult liver, and five pediatric liver recipients were affected. Onset of RV/CD infection ranged from 2 weeks to 4 years posttransplant. All patients presented with enterocolitis causing significant fluid and electrolyte loss. In adults, CD was treated with metronidazole and in children with oral vancomycin. RV infection was treated with fluid/electrolyte replacement. During diarrhea, a significant rise in tacrolimus serum level was noted. All patients cleared CD. One child developed recurrent episodes of RV infection and died from bacterial sepsis; the renal recipient died 6 months posttransplant from myocardial infarction. The remaining six patients are currently alive with well-functioning grafts. Simultaneous infection with CD and RV may lead to severe diarrhea in SORs. Both pathogens should be considered in SOR presenting with diarrhea.

Group milleri streptococci: significant pathogens in solid organ recipients.

Group milleri streptococci (GMS) comprise a heterogeneous group of streptococci including the species intermedius, constellatus and anginosus. They may cause chronic intra-abdominal and intrathoracic abscesses, which are difficult to treat. This is a retrospective analysis including 45 transplant recipients in whom GMS were isolated. The epidemiology, clinical significance and the impact on the outcome in all transplant patients with infections caused by GMS during a 4-year period (2001-2004) was evaluated. The 45 solid organ recipients (88 isolates) included 34 liver-, four kidney/pancreas-, one kidney-, two small bowel-, three combined liver/kidney- and one combined kidney/small bowel transplant recipient. In 42 cases GMS caused intra-abdominal infection, in two cases pleural empyema and in one case soft tissue infection. Only a single isolate of GMS was cultured from blood. In 54 of the 88 specimens (61%), which grew GMS, other pathogens were also isolated. GMS frequently caused recurrent cholangitis (n = 17) associated with anastomotic and nonanastomotic biliary strictures. These cases were managed by repeated stenting or surgical intervention and prolonged antibiotic therapy. No patient died directly related to GMS infection and all except one case responded to combined surgical/antibiotic treatment. One pancreas graft was lost because of erosion haemorrhage associated with an abscess. GMS were susceptible to penicillin G, carbapenems and clindamycin, whereas cephalosporins and quinolones showed intermediate activity or resistance in some cases, and GMS in general were found resistant to aminoglycosides. GMS may cause serious infections in transplant recipients which are difficult to treat. Their prevalence in transplant surgical site infections thus far may have been underestimated.