Brazil discusses the incorporation of new te

Publicação: 10 de January de 2013

Brasil discute incorporação de nova tecnologia para diagnóstico de tuberculose

The advantage of GeneXpert is its rapid production of test results: 2 hours, compared to the 30 to 60 days required for solid culture and 10 to 20 days for liquid culture

The incorporation of GeneXpert technology, which diagnoses tuberculosis, has been a frequent topic of discussion among several scientific societies and also by the Ministry of Health’s support committee for the National Tuberculosis Program (CTA-TB). The main difference between GeneXpert and the current method used in the country is the speed with which it produces test results. But, despite this, the high financial cost divides opinion regarding its implementation.

“CTA-TB remains fairly critical of the implementation of new technologies. Studies of pragmatic clinical trials, which analyze cost-effectiveness, are needed forBrazil, for different epidemiological situations and populations”, says Dr. Júlio Croda, director of the Faculty of Health Sciences, Federal University of Grande Dourados (UFGD). The doctor, who is also a representative of SBMT in CTA-TB, argues that the meetings are of great relevance, since the program’s technicians and its coordinating team can consult civil society organizations, professionals and researchers in the field, in order to make effective decisions.

“In Brazil, what would be the most effective measure: the implementation of GeneXpert in centers for patients with HIV/ AIDS? In populations with a higher prevalence of infection with MDR strains? At what level of health care?” asks the expert. He says that these are just some still unanswered questions. Croda explains that large health companies lobby for the incorporation of new technologies based only on analyzes of sensitivity and specificity, which hinders the decision of managers with regard to cost.

The day-to-day use of the new methodology is simple. According to Croda, the patient places a sputum sample in a cartridge that has a special compartment containing reagents for the PCR (polymerase chain reaction), in real time. This cartridge is inserted into the machine, which does all the processing and provides the results in approximately two hours. “The only infrastructure required is energy for the machine to function”, he observes. He says that alternatives are being developed, for example using batteries. “The technical training required to use the equipment is simple and of short duration”, he recalls.


GeneXpert is part of an innovative technology based on PCR, in real time, with minimal sample handling. The result is available in two hours and can determine resistance to Rifampicin, and detects MDR (multidrug resistant) strains. Currently, the Ministry of Health recommends the use of smear and culture, which can be solid or liquid.

However, the expert points out that studies have shown the advantage of GeneXpert in relation to other tests. “The biggest difference is in the time of examination: two hours for GeneXpert, while for solid culture it is 30 to 60 days, and for liquid culture it is 10 to 20 days. This time difference is critical, especially with the increase of MDR strains”, says Croda. He says that in the original study, the groups of patients who benefited most from this new methodology were those with MDR strains and those co-infected with HIV/AIDS.

The study for the implementation of the new examination began ??in Brazilin February 2012, inManaus (AM) and in Rio de Janeiro(RJ). The Ministry of Health reckons that GeneXpert is a major technological innovation and will be available in the public health system in the second half of 2013.

New method: reality for few
New methodologies usually bring real benefits to the population. But the expert argues that the big issue is not the acquisition of equipment and cartridges, but the level of attention and the decision over which group of people receives the new technology. “Last year, WHO led a strong movement to reduce production costs related to this new technology. However, each country should decide how it will be implemented”, says Croda, who ensures that if a lack of proper cost assessment could be disastrous in places with limited health resources.

Croda believes it is quite feasible to implement GeneXpert inBrazil. “But first, we need to answer some questions with regard to operational studies so we can decide which situations and populations will benefit from this new technology”, he warns.

The Committee advises the National Tuberculosis Program on decisions concerning the disease inBrazil. It is made up of health professionals, researchers, Program staff, representatives of various scientific societies and members of civil society. Meetings occur twice a year, inBrasilia.…