Dramatic Rise in Extensively Drug-Resistant Tuberculosis

Uncategorized Comments Off

Almost half (43.7%) of patients with multidrug-resistant (MDR) tuberculosis in 8 countries studied were resistant to at least 1 second-line drug, and 6.7% had extensively drug-resistant (XDR) tuberculosis, according to a study published online August 30 in the Lancet by Tracy Dalton, PhD, a senior service fellow in the Division of Tuberculosis Elimination at the Centers for Disease Control and Prevention in Atlanta, Georgia. MDR tuberculosis is caused by Mycobacterium tuberculosis that is resistant to at least isoniazid and rifampicin. XDR tuberculosis is caused by M tuberculosis strains that are resistant to isoniazid, rifampicin, and at least 1 drug within the fluoroquinolones and 1 antituberculosis injectable drug. Fluoroquinolones and injectable drugs are second-line antituberculosis drugs.

Most international recommendations for tuberculosis control have been developed for [MDR] tuberculosis prevalence of up to around 5%. Yet we now face prevalence up to 10 times higher in some places, where almost half of the patients with infectious disease are transmitting MDR strains of Mycobacterium tuberculosis.

According to data from the World Health Organization, 5.4% of patients with MDR tuberculosis have XDR tuberculosis.