Role of T. cruzi exposure in the pattern of T cell cytokines among chronically infected HIV and Chagas disease patients

Clinical profile and mortality in patients with T. cruzi/HIV co-infection from the multicenter data base of the "Network for healthcare and study of Trypanosoma cruzi/HIV co-infection and other immunosuppression conditions"

OBJECTIVE

Chagas disease (CD) globalization facilitated the co-infection with Human Immunodeficiency Virus (HIV) in endemic and non-endemic areas. Considering the underestimation of Trypanosoma cruzi (T. cruzi)-HIV co-infection and the risk of life-threatening Chagas Disease Reactivation (CDR), this study aimed to analyze the major co-infection clinical characteristics and its mortality rates.

METHODS

This is a cross-sectional retrospective multicenter study of patients with CD confirmed by two serological or one parasitological tests, and HIV infection confirmed by immunoblot. CDR was diagnosed by direct microscopy with detection of trypomastigote forms in the blood or other biological fluids and/or amastigote forms in inflammatory lesions.

RESULTS

Out of 241 patients with co-infection, 86.7% were from Brazil, 47.5% had <200 CD4+ T cells/μL and median viral load was 17,000 copies/μL. Sixty CDR cases were observed. Death was more frequent in patients with reactivation and was mainly caused by CDR. Other causes of death unrelated to CDR were the manifestation of opportunistic infections in those with Acquired Immunodeficiency Syndrome. The time between the co-infection diagnosis to death was shorter in patients with CDR. Lower CD4+ cells count at co-infection diagnosis was independently associated with reactivation. Similarly, lower CD4+ cells numbers at co-infection diagnosis and male sex were associated with higher lethality in CDR. Additionally, CD4+ cells were lower in meningoencephalitis than in myocarditis and milder forms.

CONCLUSION

This study showed major features on T. cruzi-HIV co-infection and highlighted the prognostic role of CD4+ cells for reactivation and mortality. Since lethality was high in meningoencephalitis and all untreated patients died shortly after the diagnosis, early diagnosis, immediate antiparasitic treatment, patient follow-up and epidemiological surveillance are essentials in T. cruzi/HIV co-infection and CDR managements.

Disagreement between PCR and serological diagnosis of Trypanosoma cruzi infection in blood donors from a Colombian endemic region

Introduction:

Chagas' disease is the leading cause of infectious myocarditis worldwide. This infection caused by Trypanosoma cruzi is usually life-long and asymptomatic; however, the third part of infected people can develop severe or even fatal cardiomyopathy. As the parasitemia in the chronic phase is both low-grade and intermittent, T. cruzi infection is principally detected by serology, although this method has sensitivity and specificity limitations.

Objective:

To determine the level of agreement between serologic and molecular tests in 658 voluntary blood donors from six provinces in the Colombian department of Santander.

Materials and methods:

We evaluated an array of diagnostic technologies by cross-section sampling performing a serological double diagnostic test for T. cruzi antibody detection (Chagas III ELISA™, BiosChile Group, and ARCHITECT Chagas CMIA™, Abbott;, and DNA detection by polymerase chain reaction (PCR). We collected the demographic, clinical, and epidemiological information of participants. The sample size was calculated using Epidat™ and the statistical analysis was done with Stata 12.1™.

Results:

PCR was six times more sensitive in detecting T. cruzi infection than ELISA/CMIA with prevalence values of 1.8% (12/658) and 0.3% (2/658), respectively, and kappa=0.28 (95%CI: -0.03 - 0.59). In contrast, serology showed a sensitivity of 16.7% (95%CI: 2.09 -48.4) and a specificity of 100% (95%CI: 99.4 - 100). All seropositive samples were found to be positive by PCR.

Conclusions:

The implementation of PCR as a complementary method for screening donors could reduce the probability of false negative and the consequent risk of transfusional-transmission of Chagas' disease, especially in endemic regions.