V. Rickerts

Prevalence of Aspergillus fumigatus and other fungal species in the sputum of adult patients with cystic fibrosis.

Summary Aspergillus fumigatus is often found in the respiratory tract secretions of patients with cystic fibrosis (CF), although the role of the fungus for progression of pulmonary disease remains unclear. This study aimed to investigate the frequency of A. fumigatus and other fungi in sputum of adult CF patients using different methods for culture and microscopy. Results from the analysis of 369 samples from 94 patients showed that A. fumigatus could be isolated in 45.7% of patients. Other moulds were rare, but the yeast Candida albicans was another frequent isolate, detected in 75.5% of patients. A comparison of different culture media showed no difference between a selective medium developed to specifically inhibit Pseudomonas aeruginosa and a standard fungal culture medium for growth of A. fumigatus, although both were more efficient for detection of fungi than other bacterial culture media. Fluorescent microscopy with calcofluor white was more sensitive for detection of fungal hyphae in undiluted sputum than standard methylene blue staining. This study shows that A. fumigatus and C. albicans have a high frequency in adult CF patients. Microbiological analysis should routinely include methods for specific identification of fungi to monitor for potential complications arising from fungal disease in these patients.

Diagnosis of invasive aspergillosis and mucormycosis in immunocompromised patients by seminested PCR assay of tissue samples

Aspergillosis and mucormycosis are the most common mold infections in patients with hematological malignancies. Infections caused by species of the genus Aspergillus and the order Mucorales require different antifungal treatments depending on the in vitro susceptibility of the causative strain. Cultures from biopsy specimens frequently do not grow fungal pathogens, even from histopathologically proven cases of invasive fungal infection. Two seminested PCR assays were evaluated by amplifying DNA of zygomycetes and Aspergillus spp. from organ biopsies of 21 immunocompromised patients. The PCR assays correctly identified five cases of invasive aspergillosis and six cases of mucormycosis. They showed evidence of double mold infection in two cases. Both assays were negative in five negative controls and in two patients with yeast infections. Sequencing of the PCR products was in accordance with culture results in all culture-positive cases. In six patients without positive cultures but with positive histopathology, sequencing suggested a causative organism. Detection of fungal DNA from biopsy specimens allows rapid identification of the causative organism of invasive aspergillosis and mucormycosis. The use of these PCR assays may allow guided antifungal treatment in patients with invasive mold infections.

Diagnosis and therapy of Candida infections: joint recommendations of the German Speaking Mycological Society and the Paul‐Ehrlich‐Society for Chemotherapy

Invasive Candida infections are important causes of morbidity and mortality in immunocompromised and hospitalised patients. This article provides the joint recommendations of the German‐speaking Mycological Society (Deutschsprachige Mykologische Gesellschaft, DMyKG) and the Paul‐Ehrlich‐Society for Chemotherapy (PEG) for diagnosis and treatment of invasive and superficial Candida infections. The recommendations are based on published results of clinical trials, case‐series and expert opinion using the evidence criteria set forth by the Infectious Diseases Society of America (IDSA). Key recommendations are summarised here: The cornerstone of diagnosis remains the detection of the organism by culture with identification of the isolate at the species level; in vitro susceptibility testing is mandatory for invasive isolates. Options for initial therapy of candidaemia and other invasive Candida infections in non‐granulocytopenic patients include fluconazole or one of the three approved echinocandin compounds; liposomal amphotericin B and voriconazole are secondary alternatives because of their less favourable pharmacological properties. In granulocytopenic patients, an echinocandin or liposomal amphotericin B is recommended as initial therapy based on the fungicidal mode of action. Indwelling central venous catheters serve as a main source of infection independent of the pathogenesis of candidaemia in the individual patients and should be removed whenever feasible. Pre‐existing immunosuppressive treatment, particularly by glucocorticosteroids, ought to be discontinued, if feasible, or reduced. The duration of treatment for uncomplicated candidaemia is 14 days following the first negative blood culture and resolution of all associated symptoms and findings. Ophthalmoscopy is recommended prior to the discontinuation of antifungal chemotherapy to rule out endophthalmitis or chorioretinitis. Beyond these key recommendations, this article provides detailed recommendations for specific disease entities, for antifungal treatment in paediatric patients as well as a comprehensive discussion of epidemiology, clinical presentation and emerging diagnostic options of invasive and superficial Candida infections.

Cluster of pulmonary infections caused by Cunninghamella bertholletiae in immunocompromised patients.

Cunninghamella bertholletiae is a rare cause of pulmonary mucormycosis. We describe a cluster of invasive pulmonary infections caused by C. bertholletiae in 4 immunocompromised patients that occurred during a 2-year period at 1 center. Three of the patients were receiving antifungal prophylaxis with itraconazole. Presenting symptoms were fever unresponsive to antibacterial chemotherapy, hemoptysis, and infiltrates on chest radiograms. Three patients were treated with liposomal amphotericin B. Only 1 patient survived.

Successful treatment of disseminated mucormycosis with a combination of liposomal amphotericin B and posaconazole in a patient with acute myeloid leukaemia.

The combination of resection of infected tissue and antifungal therapy is the treatment of choice in mucormycosis. In disseminated mucormycosis, where surgery is impossible, the mortality is almost 90%. We report the first case of disseminated mucormycosis that was cured with a combination therapy of liposomal amphotericin B and posaconazole without surgical intervention.

Rapid PCR-Based Diagnosis of Disseminated Histoplasmosis in an AIDS Patient

Abstract.Disseminated histoplasmosis is an unusual opportunistic infection in patients with advanced HIV infection living outside endemic areas. Diagnosis usually is made on the basis of isolation of Histoplasma capsulatum from clinical specimens or histologic examination. Reported is the case of an HIV-infected Columbian individual in whom the diagnosis of histoplasmosis was established within 24 h of collection of an adequate bronchoalveolar lavage specimen. The diagnosis was made by detection of specific fungal DNA and confirmed by isolation of Histoplasma capsulatum from blood, bone marrow and respiratory specimens 10 days later. The patient recovered under antifungal treatment and remained asymptomatic up to the last follow-up visit 6 months later. The polymerase chain reaction assay might be a powerful and rapid diagnostic tool for the diagnosis of non-European invasive fungal infections and should be further evaluated.

Breakthrough zygomycosis on posaconazole prophylaxis after allogeneic stem cell transplantation

S. Mousset, G. Bug, W.J. Heinz, K. Tintelnot, V. Rickerts. Breakthrough zygomycosis on posaconazole prophylaxis after allogeneic stem cell transplantation.
Transpl Infect Dis 2010: 12: 261–264. All rights reserved

Diagnosis of Disseminated Zygomycosis Using a Polymerase Chain Reaction Assay

Abstract.Invasive pulmonary zygomycosis is an uncommon opportunistic infection in patients with haematological malignancies. Clinical manifestations are indistinguishable from the more frequent invasive aspergillosis. Standard diagnostic methods like culture and microscopy from respiratory secretions have a low diagnostic sensitivity. A case in which proven invasive pulmonary zygomycosis was confirmed using a panfungal polymerase chain reaction assay in blood is presented. Since zygomycosis requires more aggressive treatment than aspergillosis (high-dose amphotericin B and surgical intervention), the polymerase chain reaction assay may improve the outcome of these often fatal infections by guiding the therapeutic approach through an early, noninvasive diagnosis.

Rhinocerebral zygomycosis in a young girl undergoing allogeneic stem cell transplantation for severe aplastic anaemia

We report on a 10‐year‐old girl with severe aplastic anaemia who developed rhinocerebral infection caused by Absidia corymbifera and a possible co‐infection caused by Alternaria alternata. Despite prolonged neutropenia, therapy with liposomal amphotericin B and posaconazole improved the clinical condition. Subsequently, the girl underwent allogeneic haematopoietic stem cell transplantation (HSCT) for the underlying disease, but the fungal infection remained under control with the antifungal treatment. No severe side effect of the antifungal drugs was noted. Unfortunately, the girl died 5 months after HSCT due to disseminated adenovirus infection.

Molekularbiologische Identifizierung von Cunninghamella spec.

Zusammenfassung. Mit den klassischen mikrobiologischen Verfahren ist eine eindeutige Identifizierung der bislang einzigen klinisch relevanten Cunninghamella‐Art, C. bertholletiae, nicht möglich. Mittels PCR und Sequenzierung der Internal‐transcribed‐spacer‐(ITS)‐DNA‐Region konnten von neun klinischen Isolaten der Gattung Cunninghamella sieben als C. bertholletiae und zwei als C. echinulata identifiziert werden. Ein Umgebungsisolat eines mit C. echinulata infizierten Patienten konnte ebenfalls als C. echinulata identifiziert werden. Alle Isolate der Spezies C. bertholletiae zeigten eine hohe Sequenzhomologie der ITS‐Region. Innerhalb der Spezies C. echinulata und C. elegans konnte aufgrund unterschiedlicher Restriktionsfragmentlängen‐Profile nach Inkubation der ITS‐Amplifikate mit TaqI und HinfI eine Subspeziesdifferenzierung erreicht werden. Ähnliche Ergebnisse wurden auch mittels PCR fingerprinting der Gesamt‐DNA mit den Microsatellit‐DNA‐Primern (GTG)5 and (GAC)5 erhalten. Erstmalig konnte C. echinulata als Erreger einer Zygomykose beim Menschen identifiziert werden.