​Assessment For Performance Of Middlebrook 7h9 With Oleic-Albumin-Dextrose-Catalase Culture Media For Isolation Of Mycobacterium Tuberculosis In Ziehl–Neelsen Smear-Positive Sputum Samples In Clinically Suspected Cases Of Tuberculosis

ABSTRACT

Introduction: Pulmonary tuberculosis (TB) is a second foremost cause of death from a communicable disease, after the HIV.Being communicable should be diagnosed at the earliest. Smear examination is preliminary step for the confirm diagnosis, butculture is still a gold standard method.Materials and Methods: The present study was carried out in the Department of Microbiology on a total of 600 smear sputumsamples from clinically suspected cases of pulmonary TB attending the outpatient and inpatient departments of MMIMSR,Mullana, Ambala, from December 2016 to June 2018. Specimens were subjected to ZN and LED staining before and afterdecontamination. After microscopy, specimens were subjected to culture on LJ and Middlebrook 7H9.Results: Mycobacterium tuberculosis was isolated in 23.33% of samples. 110 (78.57%) were detected by microscopy (ZN andLED), respectively. ZN smear positivity before and after decontamination was maximum in mucopurulent 78% and 76.63% andLED 73.63% and 72.03%. Culture positivity on Middlebrook 7H9 was 100% while 87.85% on LJ media. The rate of contaminationwas 5% and 7% on Middlebrook 7H9 and LJ media, respectively.Conclusions: Middlebrook media was superior to the conventional LJ medium in being rapid, easy to use and interpret, andsignificantly low time-to-growth detection and had lesser contamination rate because the liquid media contains growth supplementoleic-albumin–dextrose-catalase, provides additional nutrition.