TITLE:
Clinical Factors Predictive of High Bacillary Load in Pulmonary Tuberculosis
AUTHORS:
Dianguina Soumaré, Bocar Baya, Khadidia Ouattara, Tenin Kanoute, Salif Kone, Fatoumata B. Sanogo, Ibrahima Guindo, Salif Satao, Souleymane Koné, Yacouba Toloba
KEYWORDS:
Tuberculosis, High Bacterial Load, Clinical, Predictors, Mali
JOURNAL NAME:
Journal of Tuberculosis Research,
Vol.14 No.1,
January
15,
2026
ABSTRACT: Introduction: Tuberculosis (TB) remains the leading cause of preventable death from an infectious agent. Sputum smear-positive pulmonary tuberculosis (SSB) is the primary vehicle of transmission. TB contagiousness and patient prognosis are influenced by the bacterial load of the index case. This study aimed to identify clinical signs predictive of a High Bacterial Load (HBL) defined as a sputum smear microscopy result at 3+ that could guide treatment decisions or shorten the time to treatment initiation. Materials and Methods: This was a cross-sectional, analytical study conducted in the Pneumology Department of the Point G University Hospital between January 2022 and November 2025. The study population consisted of new cases of smear positive and culture-confirmed pulmonary tuberculosis (PTB+). Sociodemographic, clinical, and bacteriological data were collected in an Excel file and then analyzed using SPSS 25. Descriptive analyses, association analyses, and logistic regression were performed. The significance level was set at a 5% to 95% confidence interval. Results: A total of 464 culture-confirmed PTB+ patients were analyzed, of whom 72.0% were male, and 28.0% were female. The mean age was 33.7 ± 12.7 years, and 63.6% were ≤35 years old. HIV co-infection was present in 9.7% of cases, smoking was reported in 36.0%, and 9.9% consumed alcohol. Tuberculosis contact was reported in 23.5%, hemoptysis in 9.9%, and fever in 13.1%. Patients with High Bacterial Load (HBL) represented 74.1% of the study sample. Univariate analysis showed an association between HBL and male sex with an OR of 2.08, p = 0.001; smoking with an OR of 1.96, p = 0.004. Fever (OR = 2.24, p = 0.023) and hemoptysis (OR = 3.62, p = 0.003) were predictors of HBL. Conversely, the presence of chronic conditions and HIV infection was associated with a low risk of HBL, with ORs of 0.38 (p = 0.001) and 0.31 (p = 0.0003), respectively. Logistic regression identified smoking (OR = 1.74, p = 0.036), fever (OR = 2.19, p = 0.047), and hemoptysis (OR = 2.95, p = 0.032) as predictors of HBL. HIV was a predictor of paucibacillary sputum (OR = 0.30, p = 0.046). Conclusion: The study identified clinical predictors of a high bacillary load as determined by Sputum Smear Microscopy (SSM). These predictors could assist clinicians in triage and isolate highly contagious TB cases, as well as provide rapid care to improve patient outcomes.