Trypanosoma cruzi discrete typing units in Chagas disease patients from endemic and non-endemic regions of Argentina.

Genetic diversity of Trypanosoma cruzi may play a role in pathogenesis of Chagas disease forms. Natural populations are classified into 6 Discrete Typing Units (DTUs) Tc I-VI with taxonomical status. This study aimed to identify T. cruzi DTUs in bloodstream and tissue samples of Argentinean patients with Chagas disease. PCR-based strategies allowed DTU identification in 256 clinical samples from 239 Argentinean patients. Tc V prevailed in blood from both asymptomatic and symptomatic cases and Tc I was more frequent in bloodstream, cardiac tissues and chagoma samples from immunosuppressed patients. Tc II and VI were identified in a minority of cases, while Tc III and Tc IV were not detected in the studied population. Interestingly, Tc I and Tc II/VI sequences were amplified from the same skin biopsy slice from a kidney transplant patient suffering Chagas disease reactivation. Further data also revealed the occurrence of mixed DTU populations in the human chronic infection. In conclusion, our findings provide evidence of the complexity of the dynamics of T. cruzi diversity in the natural history of human Chagas disease and allege the pathogenic role of DTUs I, II, V and VI in the studied population.

Status and development of allied health personnel in cardiothoracic surgery in Latin America.

INTRODUCTION: The role of allied health personnel (not physician) in cardiothoracic surgery has evolved substantially since the beginnings of this discipline in the 70´s, especially in developed countries. METHODS: To explore the status of allied health personnel in cardiothoracic surgery in Latin America, a research was geared to know the general context of human resources in public health and specifically in cardiothoracic surgery. Official data from the World Health Organization and the Pan American Health Organization were acquired. An on-line survey was sent to Latin-American cardiothoracic surgeons through either scientific societies or personal e-mail, to get direct information on human resources management of the surgical services. RESULTS: There is lack of information on the medical literature regarding the allied health personnel activities in the region. Sixty one Latin American cardiothoracic centers answered the survey. The survey revealed that the profile of the allied health personnel is outlined by nurses, perfusion and anesthesiology technicians; whose routine activities are restricted to minor controls. CONCLUSIONS: At the moment, the lack of information and official data generates difficulties in analyzing the development status of allied health personnel in cardiothoracic surgery departments in the region of Latin America. In the light of the results and growing interest of developed countries in incorporating the allied health personnel to improve the work capacity and the quality of care in cardiothoracic surgery centers, it would be sensible to develop policies oriented to train and organize this activity in Latin America.

Usefulness of PCR strategies for early diagnosis of Chagas' disease reactivation and treatment follow-up in heart transplantation.

Heart transplantation (HTx) is a useful therapy for end-stage Chagas cardiomyopathy; however, Chagas reactivation remains a mayor complication. Parasitological methods offer poor diagnostic sensitivity, and use of more sensitive tools such as the Polymerase chain reaction (PCR) is usually necessary. In the present study, reactivation incidence and PCR usefulness for early reactivation diagnosis, as well as for treatment response evaluation during follow-up, were analyzed using Strout parasite detection test, in 10 of 222 consecutive HTx patients suffering Chagas cardiomyopathy. PCR strategies targeted to minicircle sequences (kDNA, detection limit 1 parasite/ 10 mL blood) and miniexon genes (SL-DNA, 200 parasite/10 mL) were performed to compare parasite burdens between samples. No patients received prophylactic antiprotozoal therapy (benznidazole). Five patients (50%) exhibited clinical reactivation within a mean period of 71.6 days; positive Strout results were observed in most cases presenting clinical manifestations. kDNA-PCR was positive 38-85 days before reactivation, whereas SLDNA-PCR became positive only 7-21 days later, revealing post-HTx parasitic load enhancement present prior to clinical reactivation development. Reactivations were successfully treated with benznidazole and generated negative PCR results. Results observed in this study indicate the value of PCR testing for an early diagnosis of Chagas reactivation as well as for monitoring treatment efficacy.

Trasplante pulmonar en la enfermedad respiratoria avanzada. Características poblacionales y evolución de los pacientes en evaluación y espera pre-trasplante / Lung transplantation for end-staged lung disease. Population characteristics and evolution of patients for evaluation and in transplant waiting list

El número de pacientes que se incluyen en programas de transplante pulmonar es creciente y su sobrevida en lista de espera depende de la posibilidad de acceder a un TxP así como de la progresión de la enfermedad de base. El objetivo de este trabajo es analizar la evolución y sobrevida de los pacientes con enfermedad respiratoria avanzada (ERA) evaluados para trasplante uni y bipulmonar

Trasplante pulmonar en la enfermedad respiratoria avanzada. Características poblacionales y evolución de los pacientes en evaluación y espera pre-trasplante / Lung transplantation for end-staged lung disease. Population characteristics and evolution of patients for evaluation and in transplant waiting list

El número de pacientes que se incluyen en programas de transplante pulmonar es creciente y su sobrevida en lista de espera depende de la posibilidad de acceder a un TxP así como de la progresión de la enfermedad de base. El objetivo de este trabajo es analizar la evolución y sobrevida de los pacientes con enfermedad respiratoria avanzada (ERA) evaluados para trasplante uni y bipulmonar

[Coronary surgery in elderly patients. In-hospital and long-term results]. / Cirugía coronaria en pacientes ancianos. Resultados hospitalarios y a largo plazo.

BACKGROUND: Taking into account the steady increase in the number of elderly patients requiring coronary artery bypass grafting, we sought to analyze the in-hospital and long-term evolution of a group of elderly patients (>/= 75 years) who underwent coronary artery bypass grafting, and to identify clinical predictors of mortality and long-term symptoms. METHODS: Between April 1996 and February 2000, 207 patients older than 75 years of age who had undergone coronary bypass grafting were prospectively and consecutively analyze. Mean age was 78.4 +/- 2.7. RESULTS: An average of 2.6 grafts/patients was constructed. Left mammary artery was used in 93% of patients. The in-hospital incidence of heart failure, atrial fibrillation, preoperative infarction and stroke was 38%, 29%, 4.8% and 2.8% respectively. The in-hospital mortality rate was 5.8%. Mean follow-up was 18 months (25th an 75th percentiles 9-29). Late mortality rate was 4.1% in eight patients. Excluding the in-hospital deaths, the estimated probability of survival (Kaplan-Meier) at 3 years was 94% and the survival freedom from symptoms was 86%. A multivariate analysis showed that only age was predictor of in-hospital mortality (OR 1.16, p = 0.009). Only peripheral vascular disease was found as a predictor of symptoms during the long-term follow-up (p = 0.001). CONCLUSIONS: In this series of senile patients who underwent coronary surgery, those of an older age (> 80 years) showed a higher risk of in-hospital mortality. The presence of peripheral vascular disease is useful in the prognosis assessment of the group.

Myocardial revascularization with radial and mammary arteries: initial and mid-term results.

BACKGROUND: The radial artery is being used with increasing frequency instead of the saphenous vein in coronary artery bypass grafts. We analyzed the in-hospital and midterm results in patients undergoing coronary artery bypass surgery in whom a combination of arterial grafts was used, including radial artery and one or both internal mammary arteries. METHODS: Between 1995 and 1998, 1,023 patients underwent coronary artery bypass surgery using arterial conduits. The left internal mammary artery and the right internal mammary artery were employed in combination with the radial artery. RESULTS: An average of 3.2 grafts per patient were done. The left internal mammary artery and radial artery were used in 100% of patients, the right internal mammary artery in 21.7%, and a venous graft in 31%. The operative mortality rate was 2.5%. On repeat angiography performed in 62 patients before their discharge, the arterial conduits were patent in 98.4%. Mean follow-up was 25.0 +/- 9.6 months (1 to 48 months). The probability of survival was 92.8%. CONCLUSIONS: Revascularization using mammary and radial artery grafts is safe. Complications are not higher than those observed with saphenous vein grafting. It was possible to use arterial conduits in all the patients, even in those with impaired left ventricular function.

[Coronary revascularization surgery with arterial conduits. The technic, results and 4-year follow-up in 1023 consecutive patients]. / Cirugía de revascularización coronaria con conductos arteriales. Técnica, resultados y seguimiento a cuatro años en 1,023 pacientes consecutivos.

OBJECTIVE: The main objective of the present study was to analyze the in-hospital and mid term results obtained in 1,023 consecutive patients undergoing coronary artery bypass surgery (CABG) in whom a combination of arterial grafts was used: radial arteries (RA) and one or both internal mammary arteries (IMA). METHODS: From May 1995 to May 1998, 1,023 consecutive patients underwent CABG alone, using arterial conduits (AC) (one or two IMA and RA) for myocardial revascularization. The left internal mammary artery (LIMA) was employed as an "in situ" graft, and the right internal mammary artery (RIMA) as a free graft or "in situ" both in combination with the RA. The latter was connected to the LIMA through a T or Y anastomosis, or emerged directly from the ascending portion of the aorta. RESULTS: An average of 3.2 bypasses per patient were performed. The LIMA was used in 100% of the patients. The RIMA was used in 21.7% and the RA in 100% of the cases. Operative mortality was 2.5% (26 patients) and 32 (3.1%) suffered perioperative acute myocardial infarction. The first 62 patients were angiographically re-studied before discharge, and a 98.4% patency of the AC used was found. Mean follow up time was 25.0 +/- 9.6 months (range, 1 to 48 months). CONCLUSIONS: a) myocardial revascularization procedures using a combination of mammary and RA grafts are safe; b) in-hospital and mid term morbidity and mortality are not higher than those observed with saphenous vein grafts; c) it is possible to achieve complete myocardial revascularization with only AC, even in patients with impaired left ventricular function, and d) AC can be used in elderly patients.

Primary pulmonary artery sarcoma resembling chronic thromboembolic pulmonary disease.

Two cases of primary pulmonary artery sarcoma resembling chronic thromboembolic disease features are presented. Tumour identification was achieved after pulmonarv thromboendarterectomy, which was indicated by documentation of a prothrombotic state in both patients. A doubtful history of pulmonary emboli or deep venous thrombosis should alert medical personnel to the possible presence of a primary pulmonary artery sarcoma. Advanced imaging methods such as gadolinium-enhanced magnetic resonance imaging could be useful in considering pulmonary thromboendarterectomy. If a tumour is detected, its surgical resection should be considered with caution, taking into account the poor survival results. Invasion of the adventitia or the right ventricle, as documented in the present cases, is unusual. As far as the present authors know, this is the first report of this kind of tumour and its coexistence with an activated protein C resistance state and type II heparin-induced thrombocytopenia.

Anti-skeletal muscle glycolipid antibodies in human heart transplantation as predictors of acute rejection: comparison with other risk factors.

In forty-five patients who underwent orthotopic heart transplantation, the titer of anti-human skeletal muscle glycolipid antibodies (AGA) present in the sera at the moment of transplantation was correlated with the number of histologically diagnosed cellular grade 3A and humoral acute rejection episodes during the first 120 days after transplantation. Determination of a cutoff value of 0.800 for the AGA level was determined by a receiver operating characteristic curve. Thirteen of 19 patients (68.4%) with an AGA titer above 0.800 developed 24 severe rejection episodes, and of the 26 patients with an AGA titer below 0.800, only 4 (15.3%) presented 6 severe rejection episodes during that time. This was especially evident for the humoral rejection episodes, which were diagnosed in only 1 of the 26 patients with AGA below 0.800 and in 7 of the 19 with AGA above 0.800. Comparison by univariate analysis of other well-known risk factors for a greater number of rejection episodes during the early posttransplant period with the AGA level at the moment of transplantation revealed that the latter distinguished a greater number of patients at risk than the other factors, such as a female donor, the lymphocyte direct cross-match, or the status of the patients at transplantation; the odds ratios were 6.33 for the AGA level, 3.17 for the direct cross-match, and 2.76 for the status at transplantation. By multiple logistic regression analysis, the only relevant risk factors in our group of patients were the AGA level (P=0.0009) and the status at transplantation (P=0.0285). These results indicate that determination of the AGA level at the moment of transplantation could represent a useful method for distinguishing which patients are at risk for a greater number of rejection episodes during the early posttransplant period, with a greater sensitivity than other risk factors.

Anti-skeletal muscle glycolipid antibodies in human heart transplantation as markers of acute rejection. Correlation with endomyocardial biopsy.

In seventeen patients the result of the histological study of 153 endomyocardial biopsies (EMB) was compared with the ELISA titer of anti-human skeletal muscle glycolipid antibodies (AGA) present in serum samples collected simultaneously with the EMB procedure during the first four months following cardiac transplantation. The glycolipids were extracted from the quadriceps femoralis of blood group O patients. In the serum samples corresponding to the histological rejection grades with myocyte necrosis (greater than or equal to 2, International Society for Heart and Lung Transplantation grading) the AGA titer was significantly higher (P<0.005) than in the less severe rejection grades. The follow-up in each patient showed that the AGA titer raised in the serum samples collected immediately after, before, or coincidentally with a histological diagnosis of rejection grade 2 or 3A. In only one rejection grade 3A case was a false-negative result observed. Determination of the cut-off of the AGA level versus rejection grades 2 and 3A was determined by a relative-operating characteristic curve. An optical density (OD) of 0.040 showed maximum efficiency with sensitivity 53% and specificity 79%. Four patients who had AGA with an OD above 0.040 at the time of transplant had a significantly higher number of rejection grade 2 and 3A episodes than eleven patients with low pre-transplant AGA titers (P<0.05). These results indicate that search of anti-skeletal muscle glycolipid antibodies may represent a useful noninvasive method for monitoring heart rejection, and suggest that its investigation prior transplant may be a predictor of the number of grades 2 and 3A rejection episodes.