Comparative study of different methods of diagnosis of invasive fungal infection in immunocompromised patients

ABSTRACT

Fungal infection is still a major cause of morbidity and mortality in cancer patients. Our study was conducted on 50 patients attending Al-Hussein university hospital complaining from different types of cancer were suffering from low grade fever, night sweat, weight loss, lassitude and easy fatigability. The cases were matched with 10 healthy controls of the same age and sex. Blood samples were collected and cultured to isolate fungal pathogens using conventional methods and BACTEC system. Positive cases were subcultured on Sabouraud dextrose Agar [SDA]. We describe a multiplex polymerase chain reaction [PCR] based approach to the detection and identification of pathogenic fungi which has potential for the diagnosis of invasive mycoses. PCR allowed the detection [universal PCR] and identification [species-specific PCR] of a fungal pathogen within 6 h from blood samples. Fungal isolates detected and identified using conventional and confirmatory methods were 7 cases [14%], while fungal isolates detected using PCR were 8 cases [18%]. Sensitivity and specificity of conventional methods in relation to PCR was; sensitivity [87.5%] and specificity [98.1%]. In our study Candida species were the only fungal pathogens with different frequency; Candida albicans [4 isolates], Candida tropicalis [2 isolates], Candida glabrata [1 isolate] and Candida parapsilosis [1 isolate]