Manormoney Pillay1, A Willem Sturm. 1. Department of Medical Microbiology, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, South Africa.
Abstract
BACKGROUND: Although several hot spots of multidrug-resistant tuberculosis have been identified on the African continent, extensive drug resistance (XDR) has not been reported until recently, when a large number of XDR cases were identified in KwaZulu-Natal. The majority of the patients involved were infected with the same strain of Mycobacterium tuberculosis (F15/LAM4/KZN). We report this strain's development from multidrug resistance to XDR. METHODS: We searched databases for studies performed during the period 1994-2005 that involved the resistance patterns of isolates of M. tuberculosis with the F15/LAM4/KZN strain fingerprint. RESULTS: As early as 1994, the F15/LAM4/KZN strain was responsible for a number of cases of multidrug-resistant tuberculosis, indicating the ability of the strain to cause cases of primary resistant tuberculosis. Some of the isolates were also resistant to streptomycin. From 1994 onwards, multidrug-resistant isolates with resistance to additional drugs were found, and the first XDR isolate was discovered in 2001. CONCLUSIONS: Drug resistance to as many as 7 drugs developed in a local strain of M. tuberculosis in slightly more than a decade. This coincided with the introduction of the directly observed therapy-based and directly observed therapy-plus-based tuberculosis-control programs. It is postulated that the introduction of these programs in the absence of susceptibility testing or drug resistance surveillance has been instrumental in the development of XDR in this highly transmissible F15/LAM4/KZN strain. The expanding pool of human immunodeficiency virus-infected, tuberculosis-susceptible individuals has likely contributed to this development.
BACKGROUND: Although several hot spots of multidrug-resistant tuberculosis have been identified on the African continent, extensive drug resistance (XDR) has not been reported until recently, when a large number of XDR cases were identified in KwaZulu-Natal. The majority of the patients involved were infected with the same strain of Mycobacterium tuberculosis (F15/LAM4/KZN). We report this strain's development from multidrug resistance to XDR. METHODS: We searched databases for studies performed during the period 1994-2005 that involved the resistance patterns of isolates of M. tuberculosis with the F15/LAM4/KZN strain fingerprint. RESULTS: As early as 1994, the F15/LAM4/KZN strain was responsible for a number of cases of multidrug-resistant tuberculosis, indicating the ability of the strain to cause cases of primary resistant tuberculosis. Some of the isolates were also resistant to streptomycin. From 1994 onwards, multidrug-resistant isolates with resistance to additional drugs were found, and the first XDR isolate was discovered in 2001. CONCLUSIONS: Drug resistance to as many as 7 drugs developed in a local strain of M. tuberculosis in slightly more than a decade. This coincided with the introduction of the directly observed therapy-based and directly observed therapy-plus-based tuberculosis-control programs. It is postulated that the introduction of these programs in the absence of susceptibility testing or drug resistance surveillance has been instrumental in the development of XDR in this highly transmissible F15/LAM4/KZN strain. The expanding pool of human immunodeficiency virus-infected, tuberculosis-susceptible individuals has likely contributed to this development.
Authors: Sanjay Basu; Gerald H Friedland; Jan Medlock; Jason R Andrews; N Sarita Shah; Neel R Gandhi; Anthony Moll; Prashini Moodley; A Willem Sturm; Alison P Galvani Journal: Proc Natl Acad Sci U S A Date: 2009-04-13 Impact factor: 11.205
Authors: Elis Regina Dalla Costa; Luiz Claudio Oliveira Lazzarini; Paulo Fernado Perizzolo; Chyntia Acosta Díaz; Fernanda S Spies; Lucas Laux Costa; Andrezza W Ribeiro; Caroline Barroco; Sandra Jungblut Schuh; Marcia Aparecida da Silva Pereira; Claudia F Dias; Harrison M Gomes; Gisela Unis; Arnaldo Zaha; Pedro E Almeida da Silva; Philip N Suffys; Maria L R Rossetti Journal: J Clin Microbiol Date: 2013-01-16 Impact factor: 5.948
Authors: Alistair D Calver; Alecia A Falmer; Megan Murray; Odelia J Strauss; Elizabeth M Streicher; Madelene Hanekom; Thelma Liversage; Mothusi Masibi; Paul D van Helden; Robin M Warren; Thomas C Victor Journal: Emerg Infect Dis Date: 2010-02 Impact factor: 6.883
Authors: Thomas R Ioerger; Sunwoo Koo; Eun-Gyu No; Xiaohua Chen; Michelle H Larsen; William R Jacobs; Manormoney Pillay; A Willem Sturm; James C Sacchettini Journal: PLoS One Date: 2009-11-05 Impact factor: 3.240