Basic and Clinical Sciences (BCSE) 2025 – 400 Free Practice Questions to Pass the Exam

The challenge of microbiological diagnosis in children with tuberculosis (TB) is significantly impacted by the prevalence of paucibacillary disease, which leads to smear negativity. In children, TB often presents with fewer bacilli compared to adults, resulting in lower bacterial loads in samples such as sputum. This paucibacillary nature makes it less likely to detect the bacteria through smear microscopy, which relies on finding visible bacilli in the specimen. As a result, even when a child is infected with TB, the diagnostic tests may yield negative results, complicating the identification and confirmation of the disease.

In many cases, particularly in young children, TB can present primarily as extrapulmonary disease, and the absence of a significant amount of bacilli can hinder the ability to obtain reliable cultures. This factor contributes to the challenges faced in accurately diagnosing TB in pediatric patients, making timely and effective treatment more difficult to initiate.