Detection of Mycobacterium tuberculosis in sputum from Suruí Indian subjects, Brazilian Amazon

This investigation aimed at the detection of Mycobacterium tuberculosis (MTB) in the sputum of Suruí Indian subjects from Amazonia, Brazil. Polymerase chain reaction analyses were positive for12 samples, five of which were also culture-positive (N = 147). Four MTB genotypes were identified, one of which showed resistance to rifampicin and isoniazid. The study also highlighted one village complex as of particular importance, considering the relatively high number of tuberculosis cases reported and of MTB isolates obtained

<it>Pfatp6 </it>molecular profile of <it>Plasmodium falciparum </it>isolates in the western Brazilian Amazon

<p>Abstract</p> <p>Background</p> <p>Anti-malarial drug resistance has emerged as one of the biggest challenges confronting the worldwide effort to control malaria. The appearance of chloroquine and multi-drug resistance had devastating effects on therapeutic efficacy of former first-line agents. Artemisinin has proven to be an excellent therapeutic alternative to fill the void in chemotherapeutic options left by resistance mechanisms. At the time of introduction, no resistance to artemisinins had been recorded, and artemisinins demonstrated excellent parasite reduction rates. In an attempt to protect artemisinin efficacy, the World Health Organization (WHO) made artemisinin-based combination therapy (ACT) its official first-line treatment recommendation for uncomplicated <it>Plasmodium falciparum </it>in 2006. In Brazil, artemether/lumefantrine became the Brazilian Malaria Control Programme's official treatment recommendation in 2007. The sarco/endoplasmic reticulum Ca^{2+ -}ATPase ortholog of <it>P. falciparum </it>(<it>pfatp</it>6) has been suggested as one of the targets of artemisinins. Consequently, <it>pfatp</it>6 gene polymorphisms are being investigated as markers of artemisinin resistance elsewhere. The goal of this work was to describe the molecular profile of <it>pfatp</it>6 in <it>P. falciparum </it>isolates from different localities in the Amazonas State.</p> <p>Methods</p> <p>DNA polymorphisms of the <it>pfatp6 </it>gene in 80 <it>P. falciparum </it>isolates from 11 municipalities of the Amazonas State (Western Brazilian Amazon), before and after the introduction of ACT in the Brazilian anti-malarial guidelines, were analysed by automatic sequencing. Mutations in the <it>pfatp6 </it>gene were searched using Mutation Surveyor v3.25 software.</p> <p>Results</p> <p>The <it>P. falciparum pfatp6 </it>gene presented polymorphisms at codons 37, 630 and 898. The R37K mutation was found in 16% of the samples, A630S in 32% and I898I in 52%. No S769N mutation, however, was detected in the analysed samples.</p> <p>Conclusion</p> <p>Despite the small number of samples, data presented here provide baseline information about polymorphisms of <it>pfatp6 </it>gene before and after exposure to ACT in a low transmission area, which will help to infer drug selection pressure in this area in the future.</p