ABO Blood Group Distribution and Sociodemographic Profile of Patients with Pulmonary Tuberculosis in Luanda, Angola

Background: Tuberculosis (TB) remains a major public health problem in sub-Saharan Africa. Although host genetic factors may influence susceptibility to infectious diseases, the relationship between ABO/Rh blood groups and pulmonary TB remains incompletely understood, particularly in African populations. Herein, we characterise the distribution of ABO/Rh blood groups and the demographic profile of patients with pulmonary TB in Luanda, Angola. Methods: This was a cross-sectional study conducted among patients with pulmonary TB treated at Hospital Divina Providência, Luanda, during the second semester of 2020. A total of 110 patients were selected by simple random sampling. Sociodemographic data were collected and ABO/Rh blood groups determined using anti-A, anti-B, and anti-D reagents. Results: Among the 110 participants, O+ was the most prevalent phenotype (51; 46.4%), followed by A+ (29; 26.4%), B+ (25; 22.7%), and AB+ (5; 4.5%). The mean age was 31.5 years, and males accounted for 57.3% of participants. Most participants had non-higher education (89.1%) and resided in Kilamba Kiaxi municipality (75.5%). ABO phenotype was not associated with age (p=0.423) or sex (p=0.522). Also, ABO was not associated with educational level (p=0.125), residence (p=0.769), occupation (p=0.864), alcohol consumption (p=0.748), or associated infections (p=0.365). Conclusion: The O+ blood group was the predominant ABO/Rh phenotype among patients with pulmonary TB in Luanda, followed by A+, B+, and AB+. No associations were identified between ABO phenotype and demographic or clinical characteristics. Larger multicentre studies incorporating appropriate non-TB control groups are warranted to clarify the potential relationship between ABO phenotypes and TB susceptibility in Angola.