Volume 14, Issue 2 (2-2026)                   JoMMID 2026, 14(2): 168-177 | Back to browse issues page

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Nkem Awujo C, Gaina E, Brown S. Isolation of Cryptococcus Species from Sputum of Patients with Presumptive Pulmonary Tuberculosis Attending a Referral Hospital in Cross River State, Nigeria. JoMMID 2026; 14 (2) :168-177
URL: http://jommid.pasteur.ac.ir/article-1-769-en.html
Isolation of Cryptococcus Species from Sputum of Patients with Presumptive Pulmonary Tuberculosis Attending a Referral Hospital in Cross River State, Nigeria
Chinedu Nkem Awujo * , Emmanuel Gaina , Samuel Brown
Department of Microbiology, Faculty of Biosciences, Federal University Wukari, P.M.B. 1020, Wukari, Taraba State, Nigeria
Abstract:   (12 Views)
Introduction: The differential diagnosis of pulmonary tuberculosis (TB) and fungal infections is important in influencing treatment strategies and enhancing therapeutic success. Therefore, this study aimed to investigate the prevalence of Cryptococcus species among presumptive tuberculosis patients in a referral hospital in Nigeria. Methods: This cross-sectional, hospital-based study was carried out between October 2024 and January 2025. A total of 174 sputum samples were tested for the presence of Mycobacterium tuberculosis using Ziehl-Neelsen staining and the molecular GeneXpert MTB/RIF assay; Cryptococcus species were isolated by culture on Sabouraud Dextrose Agar (SDA) and presumptively identified as encapsulated yeasts using India ink staining. Results: None of the samples (0%) obtained from presumptive tuberculosis patients were positive for M. tuberculosis, highlighting the importance of investigating other pathogens, such as Cryptococcus species, in patients presenting with TB-like symptoms. Cryptococcus species were isolated from 21 of 174 patients, giving an overall prevalence of 12.1%. A significant gender disparity was observed, with females showing a much higher prevalence (35.2%) compared with males (1.7%). Age was not significantly associated with infection status, although individuals aged 50–59 years had the highest age-specific prevalence, with 4 out of 20 patients (20.0%) testing positive. Statistical analysis confirmed the significant gender difference (χ² = 39.426, P < 0.001), while the association with age was not statistically significant (Fisher–Freeman–Halton exact test statistic = 7.681, P = 0.199). No Cryptococcus isolates were recovered from participants aged 1–9 years, 40–49 years, and ≥ 60 years. Conclusion: The moderate prevalence of Cryptococcus species observed in this study suggests their potential as a lower respiratory tract pathogen in presumptive tuberculosis patients. The results of this study show the need to integrate fungal screening into routine diagnostic protocols for tuberculosis, especially where fungi such as Cryptococcus species are often neglected.
Keywords: Cryptococcus species, Presumptive, Pulmonary, Tuberculosis, Prevalence, Cross River State, Nigeria
Full-Text [PDF 1066 kb]   (4 Downloads)    
Type of Study: Original article | Subject: Infectious diseases and public health
Received: 2025/08/16 | Accepted: 2026/02/21 | Published: 2026/09/7
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Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

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This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.