Investigation of ergosterol and chitin for the diagnosis of invasive fungal infections
Also available in printed version
| 第一著者: | |
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| その他の著者: | |
| フォーマット: | Doctoral thesis |
| 言語: | 英語 |
| 出版事項: |
Universiti Teknologi Malaysia
2025
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| 主題: | |
| オンライン･アクセス: | https://utmik.utm.my/handle/123456789/47758 |
| Abstract | Abstract here |
| _version_ | 1854975059640188928 |
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| author | Ahmad Sh. Ahmad Al-Ani |
| author2 | Fahrul Zaman Huyop, supervisor |
| author_facet | Fahrul Zaman Huyop, supervisor Ahmad Sh. Ahmad Al-Ani |
| author_sort | Ahmad Sh. Ahmad Al-Ani |
| description | Also available in printed version |
| format | Doctoral thesis |
| id | utm-123456789-47758 |
| institution | Universiti Teknologi Malaysia |
| language | English |
| publishDate | 2025 |
| publisher | Universiti Teknologi Malaysia |
| record_format | dspace |
| record_pdf | Abstract |
| spelling | utm-123456789-477582025-08-20T21:43:28Z Investigation of ergosterol and chitin for the diagnosis of invasive fungal infections Ahmad Sh. Ahmad Al-Ani Fahrul Zaman Huyop, supervisor Biosciences and medical engineering Also available in printed version Invasive fungal infections (IFIs) have grown in importance over the last three decades, largely because of the growing size of the community at risk. Current methods for diagnosing these infections are lack with accuracy, sensitivity, specificity and time consuming. In this study, two fungal components namely ergosterol, a fungus-specific part associated with the cell plasma membrane and chitin, a skeletal cell polysaccharide derived from the inner cell wall of fungi were investigated for their possible use as biomarkers of IFI. A novel method using High Performance Liquid Chromatography (HPLC) technology was developed for detection of these components in fungal cell extracts and clinical samples. Routine evaluation of the optimized HPLC method was designed in terms of specificity, linearity, detection and quantification limits, precision and accuracy. Ergosterol and chitin were extracted from broth cultures of 10 pathogenic fungal species (Aspergillus fumigatus, Aspergillus niger, Candida albicans, Candida tropicalis, Cryptococcus gattii, Cryptococcus neoformans, Fusarium solani, Penicillium sp., Mucor sp., Rhizopus sp.) representing three different fungal phyla (Ascomycota, Basidiomycota & Zygomycota) while ergosterol was also detected in spiked human whole blood and serum samples. Thereafter, determination of ergosterol in serum samples of patients from Hospital Sultanah Aminah (HSA) and Hospital Canselor Tuanku Muhriz (HCTM) was performed using the optimized and validated HPLC methodology. The ergosterol content in the mycelium of pathogenic fungal species ranged from 4.62 �g/mg in Aspergillus niger to 22.84 �g/mg in Candida tropicalis. The chitin content was varied from 18.61 (� 0.09) to 47.12 (� 0.50) �g per mg dry mycelial weight. Candida albicans and Cryptococcus neoformans exhibited the highest and lowest levels of chitin, respectively. The presence of ergosterol and chitin in all the major pathogenic fungal species tested indicates their possible use as biomarkers for diagnosis and prognosis of fungal infection in patients. The ergosterol levels in spiked whole blood samples were demonstrated to be lower than in serum, indicating that serum samples would provide more sensitive diagnosis of IFI in patients. The presence of fungal infection as determined by ergosterol detection in 96 clinical serum samples from HSA in Johor Bahru and HCTM in Kuala Lumpur, resulted in 38 true positive samples, 7 false negative samples, 25 false positive samples, and 26 true negative samples, compared to routine laboratory diagnostic tests that included both serology and culture. The sensitivity for the ergosterol detection assay was 84.45 %, specificity was 50.99 %, positive predictive value (PPV) was 0.607 and negative predictive value (NPV) was 0.788. The relatively low specificity value may be due to the higher sensitivity of ergosterol detection compared to culture and serology in detecting IFI. Remarkably, those 22 serum samples that had no indication for fungal infection (control negative samples) showed no presence of ergosterol either. It was concluded that ergosterol may be used as a biomarker to diagnose invasive fungal infections in clinical serum samples, while chitin needs to be investigated further to evaluate its diagnostic utility. fahmimoksen UTM 255 p. Thesis (Doktor Falsafah (Kejuruteraan Bioperubatan)) - Universiti Teknologi Malaysia, 2019 2025-03-12T05:58:51Z 2025-03-12T05:58:51Z 2019 Doctoral thesis https://utmik.utm.my/handle/123456789/47758 vital:130177 valet-20191104-11490 ENG Closed Access UTM Complete Unpublished Completion application/pdf Universiti Teknologi Malaysia |
| spellingShingle | Biosciences and medical engineering Ahmad Sh. Ahmad Al-Ani Investigation of ergosterol and chitin for the diagnosis of invasive fungal infections |
| thesis_level | PhD |
| title | Investigation of ergosterol and chitin for the diagnosis of invasive fungal infections |
| title_full | Investigation of ergosterol and chitin for the diagnosis of invasive fungal infections |
| title_fullStr | Investigation of ergosterol and chitin for the diagnosis of invasive fungal infections |
| title_full_unstemmed | Investigation of ergosterol and chitin for the diagnosis of invasive fungal infections |
| title_short | Investigation of ergosterol and chitin for the diagnosis of invasive fungal infections |
| title_sort | investigation of ergosterol and chitin for the diagnosis of invasive fungal infections |
| topic | Biosciences and medical engineering |
| url | https://utmik.utm.my/handle/123456789/47758 |
| work_keys_str_mv | AT ahmadshahmadalani investigationofergosterolandchitinforthediagnosisofinvasivefungalinfections |