High infection rates ofTriatoma dimidiataare associated with low levels ofTrypanosoma cruziseroprevalence in Pedro Carbo, Ecuador. Use of atc24 gene-based PCR approach

In control programs for vectorial transmission of Chagas' disease, conventional microscopic procedures are generally performed to determine baseline levels of infectivity of vectors. Reported here are data using Polymerase Chain Reaction in the detection of Trypanosoma cruzi in Triatoma dimidiata, one of the principal vectors of Chagas' disease in Ecuador. The microscopy and PCR techniques showed a high percentage of vector infection in Pedro Carbo, province of Guayas (Ecuador), with 44.16% and 46.13% positive insects, respectively. This contrasted with the very low Chagas seropositivity recorded (0.5%). Since T. dimidiata was the only vector of the Chagas' disease found in Pedro Carbo and looking at the vector behavior, our data suggest that despite the high T. dimidiata infection, the low Chagas seropositivity detected is closely associated with the epidemiological and ecological context of T. dimidiata in Pedro Carbo.

[Myocardial perfusion SPET in the detection of coronary artery disease in orthotopic heart transplantation]

The incidence of atherosclerosis of the heart transplant in long term survivors is 38% at 5 years. In the present work, myocardial perfusion 201Tl-SPET was assessed as a non-invasive diagnostic method for the detection of postransplant coronary artery disease, as well as its efficiency with regard to other techniques. Twenty patients, aged (47 +/- 9) years old, who underwent heart transplantation at least 3 years earlier, were studied by 201Tl-SPET. Qualitative and quantitative analysis of the images were performed. It was found ischemia in 6 patients, 4 of them asymptomatics. In 5 of the 6 positive cases by SPET coronary stenosis was found by angiography. Kappa coefficient and percent of agreement were k = 0. 76 and Pe = 90%, respectively. There were no relationships among rejection crisis, sepsis by cytomegalovirus and coronary artery disease detected by using 201Tl-SPET (p > 0.05). The most relevant risk factors in the sample were hypertension and hyperlipidemia. Two patients died because of coronary artery disease. It was confirmed by necropsy findings. These results suggest that thallium-201 myocardial perfusion tomography could be useful to detect coronary artery disease in the transplanted heart.