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Antifungal prophylaxis with posaconazole (POS) has been shown to decrease the mortality associated with invasive fungal infections in high-risk patients. We report on a patient, with severe graft-versus-host disease after allogeneic stem cell transplantation, who developed proven pneumonia due to Rhizopus microsporus after 40 days of POS prophylaxis (fasting serum levels: 691-904 ng/mL). Despite combination treatment with liposomal amphotericin B and POS for 39 days, the patient died from pulmonary hemorrhage. This case highlights the need for continued awareness of breakthrough zygomycosis in patients receiving POS.

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.

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.

Background: Invasive fungal infections are often diagnosed by histopathology without identification of the causative fungi, which show significantly different antifungal susceptibilities., Aims: To establish and evaluate a system of two seminested polymerase chain reaction (PCR) assays to identify and discriminate between agents of aspergillosis and mucormycosis in paraffin wax embedded tissue samples., Methods: DNA of 52 blinded samples from five different centres was extracted and used as a template in two PCR assays targeting the mitochondrial aspergillosis DNA and the 18S ribosomal DNA of zygomycetes., Results: Specific fungal DNA was identified in 27 of 44 samples in accordance with a histopathological diagnosis of zygomycosis or aspergillosis, respectively. Aspergillus fumigatus DNA was amplified from one specimen of zygomycosis (diagnosed by histopathology). In four of 16 PCR negative samples no human DNA was amplified, possibly as a result of the destruction of DNA before paraffin wax embedding. In addition, eight samples from clinically suspected fungal infections (without histopathological proof) were examined. The two PCR assays detected a concomitant infection with Absidia corymbifera and A fumigatus in one, and infections with Rhizopus arrhizus and A fumigatus in another two cases., Conclusions: The two seminested PCR assays described here can support a histopathological diagnosis of mucormycosis or aspergillosis, and can identify the infective agent, thereby optimising antifungal treatment.

Zygomycosis (mucormycosis) is a relatively uncommon infection in immunocompromised patients most often diagnosed in patients with haematological malignancies and neutropenia. Postmortem series demonstrate a high mortality rate up to 80%. Pulmonary involvement mimicking the more frequently diagnosed invasive aspergillosis is the typical clinical presentation. Other risk factors for the development of zygomycosis that have been described in other patient populations include diabetic ketoacidosis, iron overload, use of deferoxamine and steroids. If these factors are also associated with zygomycosis in patients with haematological malignancies has not been described. In a retrospective case-control study including 13 patients with zygomycosis and 13 control patients with the same underlying diseases, without zygomycosis we determined the frequency of various risk factors. Patients with zygomycosis experienced a longer period of neutropenia (17 vs. 13 days) and lymphopenia (23 vs. 20 days). A relapse of their underlying disease was diagnosed more frequently in patients with zygomycosis (7/13 vs. 3/13) as were a diagnosis of diabetes mellitus (6/13 vs. 3/13) and a cardiovascular disease (6/13 vs. 1/13). The previous use of steroids was more frequent in patients with zygomycosis (8/13 vs. 4/13) as was a systemic antifungal prophylaxis with itraconazole (9/13 vs. 4/13). Knowledge of these risk factors may be of benefit in diagnosing and monitoring zygomycosis in patients with haematological malignancies.

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.

Establishing the etiology of invasive fungal infections is important to guide therapeutic options and for epidemiologic purposes. Formalin-fixed, paraffin-embedded (FFPE) tissue specimens from patients with proven invasive fungal infections are valuable to determine the etiology of systemic fungal infections. We compared different polymerase chain reaction (PCR) amplification strategies from FFPE tissue blocks to identify agents of invasive fungal infections. We found that specific PCR assays show superior sensitivity in the identification of DNA of Mucorales and Aspergillus and mixed infections caused by both as compared to broad-range PCR assays. Shorter amplicon lengths and less detection of contaminating fungal DNA are potential factors involved. However, detection of fungal DNA by highly sensitive specific PCR assays in the absence of demonstration of fungal elements in tissue suggests that PCR results should be interpreted in the context of the histopathology and clinical findings. [ABSTRACT FROM AUTHOR]

Zygomykosen (Mucormykosen) sind seltene Erkrankungen bei immunsupprimierten Patienten meist infolge von zytostatischer Therapie hämatologischer Neoplasien. Klinik und Pathogenese ähneln weitgehend denen einer invasiven Aspergillose. In retrospektiven Studien wird eine hohe Mortalität von etwa 80% berichtet. Als weitere Risikofaktoren wurden bei Patienten mit anderen Grunderkrankungen eine Eisenüberladung, die Therapie mit Glucokortikosteroiden oder Chelatbildnern und eine diabetische Ketoazidose beschrieben. Ob diesen Faktoren eine zusätzliche Bedeutung bei hämatologischen Patienten zukommt, ist wenig untersucht worden. In einer Fall-Kontrollstudie wurde die Häufigkeit verschiedener Risikofaktoren bei 13 Patienten mit Zygomykose und 13 Kontrollpatienten mit gleicher Grunderkrankung, gleicher Therapie ohne Zygomykose untersucht. Patienten mit Zygomykose waren länger neutropen (17 vs. 13 Tage) und lymphopen (23 vs 20 Tage). Sie hatten häufiger ein Rezidiv ihrer Grunderkrankung (7/13 vs. 3/13), wurden häufiger mit Kortikosteroiden behandelt (8/13 vs. 4/13). Ebenso fand sich häufiger eine kardiovaskuläre Grunderkrankung (6/13 vs. 1/13), ein Diabetes mellitus (6/13 vs. 3/13) und eine systemische Prophylaxe mit Itraconazol (9/13 vs. 4/13). Die Kenntnis von Risikofaktoren für eine Zygomykose sollte eine raschere Diagnose, eine konsequente Therapie mit hochdosiertem Amphotericin B und gegebenenfalls eine chirurgische Intervention ermöglichen und damit die Prognose dieser Infektion verbessern. Zygomycosis (mucormycosis) is a relatively uncommon infection in immunocompromised patients most often diagnosed in patients with haematological malignancies and neutropenia. Postmortem series demonstrate a high mortality rate up to 80%. Pulmonary involvement mimicking the more frequently diagnosed invasive aspergillosis is the typical clinical presentation. Other risk factors for the development of zygomycosis that have been described in other patient populations include diabetic ketoacidosis, iron overload, use of deferoxamine and steroids. If these factors are also associated with zygomycosis in patients with haematological malignancies has not been described. In a retrospective case-control study including 13 patients with zygomycosis and 13 control patients with the same underlying diseases, without zygomycosis we determined the frequency of various risk factors. Patients with zygomycosis experienced a longer period of neutropenia (17 vs. 13 days) and lymphopenia (23 vs. 20 days). A relapse of their underlying disease was diagnosed more frequently in patients with zygomycosis (7/13 vs. 3/13) as were a diagnosis of diabetes mellitus (6/13 vs. 3/13) and a cardiovascular disease (6/13 vs. 1/13). The previous use of steroids was more frequent in patients with zygomycosis (8/13 vs. 4/13) as was a systemic antifungal prophylaxis with itraconazole (9/13 vs. 4/13). Knowledge of these risk factors may be of benefit in diagnosing and monitoring zygomycosis in patients with haematological malignancies. [ABSTRACT FROM AUTHOR]