الفهرس 
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Abstract
This hospital based descriptive study was conducted over a period of 21 months from September 2014 to May 2016 to include 135 patients who were admitted to different intensive care units (ICUs) and Oncology Department at Assiut University Hospitals.
This work was designed to identify the common fungal species causing pulmonary infection in immunocomprimised patients and their in vitro antifungal sensitivity pattern, to determine enzymatic and toxigenic ability of isolated fungi and also, to detect 1,3 β-D glucan in serum.
Out of 135 patients included in the current study; 90 (66.7%) patients were males while the other 45 (33.3%) patients were females. Mean age was 48.97 ± 14.49 years with a range of the age between 16 and 83 years.
Analysis of different risk factors revealed that the most common frequent risk factor was antibiotic therapy, presented in 69 (51.1%) patients, followed by malignant disease and diabetes mellitus presented in 46 (34.1%) and 37 (27.1%) patients respectively.
The clinical manifestations in the studied groups were non-specific and there were no significant differences between those with positive fungal infections versus those with negative fungal infection. The most frequent manifestation was cough that presented in 119 (88.1%) patients followed by fever, expectoration and hemoptysis in 55 (40.7%), 41 (30.4%) and 10 (7.4%) patients respectively.
Chest x-ray findings had insignificant differences between both positive and negative fungal cultures where consolidation was the most frequent finding in 43 (31.8%) patients followed by cavitary lesion in 33 (24.4%).
Direct microscopic examination showed that 17 samples were diagnosed as positive for fungal infection while 80 samples were positive for fungal growth when inoculated on Sabouraud Dextrose Agar. Out of these 80 positive samples, 13 (8.9%) showed mixed fungal infection while in the remaining 67 (50.4%) were caused by a single fungus.
For yeast identification, Conventional phenotypic methods including culture on chromogenic media (Brilliance Candida agar and chrOMAgarTM Candida), biochemical characteristics (included in API strips), germ tube test and chlamydospore production on cornmeal agar were used which identified 98.5% of yeast isolates. Sequencing of rRNA gene were used both for confirmation of the results and identification of the unidentified isolates.
C. albicans represented 57.6% of yeast isolates. Candida non albicans (CnA) isolates were: C. glabrata (15.1%), C. tropicalis (15.1%), C. krusei (6.1%), C. Kefyr (1.5%). Yeasts other than Candida included: Saccharomyces paradoxus (3%) and Hanseniaspora guilliermondii (1.5 %).
For moulds, identification was primarily on the basis of their macroscopic and microscopic morphologic features and confirmed by sequencing of rRNA gene. The most frequent mould isolates were A. flavus (35.5%) and A. niger (32.1%).
Determination of in vitro antifungal susceptibility pattern for yeast strains showed that Amphotericine B followed by Nystatin and fluconazole were the most active drugs affecting 90.9%, 78.8% and 39.4% of strains. Antifungal resistance was mainly related to azoles as 65.2% & 57.6% of strains were resistant to itraconazole and fluconazole respectively. For mould isolates the most active drugs were voriconazole (71.4%), amphotericin B (57.1%) then nystatin (50%). Higher rates of resistance were observed in moulds as 92.8%, 75% and 57.1% of strains were resistant to fluconazole, itraconazole and ketoconazole respectively.
Determination of the enzymatic and toxigenic ability of isolated fungal pathogens revealed that 78.6% of the tested mould strains were able to produce mycotoxins at variable levels. For yeast strains 65.2% of isolated yeasts possessed proteolytic activity and 91.9% had lipolytic activity. For mould strains 78.6% were urease positive while 100% and 89.3% of isolated strains had proteolytic and lipolytic activity respectively.
Finally, (1-3)-β-D glucan ELISA assay was used as supportive evidence for the presence of an IFI. Results showed that out of 80 serum samples; only 16 (20%) samples were positive for 1, 3 β D glucan while the remaining 80% were negative