Elevated Serum Procalcitonin an Adjunct for Early detection of Infant Tuberculosis in Paediatric HIV/AIDS

Abstract

In countries with a high tuberculosis (TB) burden, Mycobacterium tuberculosis is a frequent cause of acquired pneumonia (AP) amongst people living with HIV/AIDS and the differential and early diagnosis of TB from common bacterial pneumonia is difficult. The varying clinical and radiographic presentation of Acquired Pneumonia and Tuberculosis according to patient age and comorbidity and the low sensitivity of acid-fast bacillus microscopy make it even more difficult to distinguish TB from common bacterial pneumonia. Therefore, an adjunct diagnostic method that can determine early pulmonary tuberculosis in infants living with HIV/AIDS in order to differentiate it from other bacterial pathogens causing acquired pneumonia. Although a confirmatory microscopy test for Tuberculosis detection was carried out which would have a clinical role in terms of isolating patients with TB and administering appropriate anti-TB medication or antibiotic treatment at an early stage. The use of serum procalcitonin (PCT) for early detection of pulmonary tuberculosis (TB) from infants with paediatric HIV/AIDS in Adamawa state, Nigeria a country with an intermediate TB burden and one with the highest number of people living with HIV/IADS in West-Africa. A prospective study, enrolling 50 infants with paediatric HIV/AIDs with suspected Pulmonary Tuberculosis in a community-based referral hospital. A clinical assessment was performed before treatment, serum and PCT were measured. The test results were compared to the final diagnoses 50 patients, 35 had Pulmonary Tuberculosis and 15 had bacterial associated pneumonia TB. The median PCT level was 0.564 ng/mL (range, 0.01 to 27.75) with bacterial acquired pneumonia and 0.044 ng/mL (range, 0.01 to 0.87) with pulmonary TB (p<0.001). No difference was detected in the discriminative values of PCT (p=0.733).The concentrations of PCT differed significantly in patients with pulmonary TB and bacterial acquired Pneumonia. The high sensitivity and negative predictive value for early detection pulmonary TB when compared to bacterial acquired pneumonia suggest a supplementary role of PCT in the diagnostic exclusion of pulmonary TB from bacterial AP in areas with an intermediate prevalence of pulmonary TB.