Failure of BACTEC™ MGIT 960™ to detect Mycobacterium tuberculosis complex within a 42-day incubation period

Sharana Mahomed; Nomonde R Dlamini-Mvelase; Moses Dlamini; Koleka Mlisana

doi:10.4102/ajlm.v6i1.537

Failure of BACTEC™ MGIT 960™ to detect Mycobacterium tuberculosis complex within a 42-day incubation period

Afr J Lab Med. 2017 Apr 26;6(1):537. doi: 10.4102/ajlm.v6i1.537. eCollection 2017.

Authors

Sharana Mahomed^{1

2}, Nomonde R Dlamini-Mvelase^{1

2}, Moses Dlamini¹, Koleka Mlisana^{1

2}

Affiliations

¹ National Health Laboratory Services, Inkosi Albert Luthuli Central Hospital, Durban, KwaZulu Natal, South Africa.
² Department of Medical Microbiology, University of KwaZulu-Natal, Durban, South Africa.

Abstract

For the optimal recovery of Mycobacterium tuberculosis from the BACTEC™ Mycobacterium Growth Indicator Tube 960™ system, an incubation period of 42-56 days is recommended by the manufacturer. Due to logistical reasons, it is common practice to follow an incubation period of 42 days. We undertook a retrospective study to document positive Mycobacterium Growth Indicator Tube cultures beyond the 42-day incubation period. In total, 98/110 (89%) were positive for M. tuberculosis complex. This alerted us to M. tuberculosis growth detection failure at 42 days.