जर्नल ऑफ़ मेडिकल डायग्नोस्टिक मेथड्स
खुला एक्सेस

अमूर्त

Diagnostic performance of a multiplex PCR in identifying pneumonia micro-organisms in sputum of HIV positive patients in Uganda

Daniel Orit, William Worodria, Alfred Andama, Henry Kajumbula, Emmanuel Mande, Richard Kwizera

Background: Pneumonia remains a frequent cause of morbidity and mortality among HIV infected people in sub- Saharan Africa. A disease with such a burden requires an appropriate diagnostic modality to allow a logical approach to guide treatment. Conventional diagnostic methods although available are not fully utilized due to associated diagnostic limitations, and as such present challenges in the successful management of pneumonia. It is therefore necessary to evaluate a multiplex Polymerase Chain Reaction (PCR) assay that is rapid, sensitive and specific in detection of pneumonia microorganisms hence improving time to antimicrobial therapy.

Objective: We aimed to compare the performance of the Bio Fire^® Film Array^® pneumonia multiplex PCR panel against a composite reference standard.

Methods: Between November 2019 to February 2020, we conducted a diagnostic cross-sectional study among HIV positive clients accessing care at Mulago national referral hospital in Kampala. All consenting patients meeting the inclusion criteria were educated on quality sputum collection and two sputum samples obtained from them for analysis. Bartlett’s grading was done on sputum samples prior to bacterial culture. Multiplex PCR tests were done on the second sputum samples. Data was analysed using STATA V14. A composite reference was used as the Gold standard.

Results: Compared to the composite reference standard, the sensitivity was 90.3%, specificity of 44.6%, positive predictive value of 36.8%, negative predictive value of 91.3%, Area under the ROC Curve of 0.680, the Kappa statistic was 0.23 and a 57% agreement between the two tests.

Conclusions: A high sensitivity and low specificity demonstrated by Multiplex PCR makes it a good screening test but not a confirmatory test for detecting pneumonia microorganisms in sputum.