Evaluation of the Same Day Diagnosis of TB Microscopy in Comparison with Spot-Morning-Spot Method in Selected Public Health Institutions, Addis Ababa, Ethiopia

Abstract

Background: The need to collect serial sputum specimens over multiple patient visits for pulmonary tuberculosis results in a protected diagnostic process with rates of patients with high rates of patient dropout. Recent studies on Spot Morning Spot (SMS) method of examination PTB reported that the first two specimens have high smear positivity in line with this WHO changed its policy to minimize the number of sputum specimens from three to two. Methods and Materials: Across-sectional study was conducted in 16 conveniently selected private clinics, governmental health centers, public and private hospitals from September 2017-December 2018. Individuals attending the selected health institutions for the diagnosis of MTB submitted three sputum samples for routine diagnosis (the standard approach). One additional sample was collected 1 h after the first sputum (the same-day approach). One sputum sample was cultured. The diagnosis was performed using ZN sputum smear microscopy and Light-Emitting Diodes Fluorescent Microscopy (LED-FM) technique. Data were entered and analyzed using SPSS version 16. We used sensitivity, specificity and predictive values for the different methods. Result: A total of 209 participants enrolled, 43 (21%) were identified culture positive, 39 (18.7%) were detected by the same day approach and 40 (19.1%) by the standard approach. On the other hand, LED-FM and ZN microscopy detected 39 (18.1%) and 48 (23%) tuberculosis cases respectively. Sensitivity was 88.4% for ZN microscopy and 95.3% for LED-FM and the specificity was 99.4% and 95.9% for ZN and LED-FM microscopy respectively. Conclusion: Using the same day approach together with LED-FM would reduce workload, TAT, patient drop out and increase the smear detection rate. Therefore it is necessary to give in-service and off service training for health personnel towards the use of LED-FM, conventional approach and the same day approach in the diagnosis of TB.