Strategy successfully identified high proportion of MDR-TB cases in Peru

Velasquez G. Emerg Infect Dis. 2011. doi10.3201/eid1703.101553.

Guidelines from the Peruvian National Tuberculosis Control Program specifying criteria for culture and drug-susceptibility testing in combination with decentralized, district-level screening effectively helped to identify a significant proportion of patients with multi-drug resistant tuberculosis in the country between 2005 and 2008, according to recent findings published in Emerging Infectious Diseases.

Gustavo E. Velasquez, MD, of Brigham and Women’s Hospital in Boston, and colleagues said, “The strategy implemented in Lima was especially effective in detecting MDR-TB among patients with new smear-positive TB.”

In the prospective study, the researchers monitored all patients with suspected TB and respiratory symptoms originally referred for culture and drug-susceptibility testing at two sites in Lima. All patients met Peruvian National Tuberculosis Control Program guidelines for drug-susceptibility referral.

Of 1,846 participants, 67.2% had complete drug-susceptibility testing results; 33.8% had MDR-TB at time of referral; 46.5% had never been treated for TB; and 53.5% were previously treated for TB. Patients with MDR-TB were more likely to be younger, single, less likely to have ever smoked, and had higher education when compared with patients with drug-susceptible TB.

In addition, the researchers observed a significantly higher relative risk for MDR-TB among patients with new smear-positive TB who had diabetes (16.8%), were adult or child patients with household contacts with MDR-TB (33.5% and 53.9%, respectively), and those with a positive smear or culture during the second or third month of category I therapy (66.7%).

“Peru has had considerable success designing a strategy to detect cases with MDR-TB by targeting individuals who have specific risk factors,” Sonya S. Shin, MD, study researcher in the division of global health equity at Brigham and Women’s Hospital, told Infectious Disease News. “This strategy could serve as a strong model for other settings where the epidemiology of MDR-TB is understood, although other considerations, such as simplicity of implementation, resources for drug susceptibility testing, and treatment algorithms for suspected and confirmed MDR-TB cases must be taken into account. It is important to consider screening for MDR in all of these groups or assess whether these groups are at risk for MDR across other sites.”

Disclosure: Dr. Shin reports financial support from Eli Lilly Foundation for TB research in Russia.

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