Using polymerase chain reaction in early diagnosis of re-activated Trypanosoma cruzi infection after heart transplantation.
BACKGROUND
Heart transplantation is an effective treatment for patients with end-stage Chagas' heart disease. Re-activation of Chagas' disease in transplant recipients is frequent, triggered by immunosuppression level. Therefore, highly sensitive methods for early diagnosis of Chagas' disease relapse are necessary to initiate appropriate therapy. We analyzed the use of polymerase chain reaction (PCR) in the clinical follow-up of heart transplant recipients.


METHODS
We prospectively evaluated 4 heart transplant recipients at the Hospital Privado, Cordoba, Argentina, who had terminal Chagas' disease. The parameters analyzed were presence of parasites in the blood (blood culture, Strout) and in endomyocardial biopsy (EMB) samples, and PCR was performed with oligonucleotides directed to a nuclear repetitive sequence of Trypanosoma cruzi. We evaluated these parameters weekly from the day of transplantation until results were negative and then during regular follow-up visits.


RESULTS
In 2 patients, we detected T cruzi using PCR in peripheral blood 30 days before clinical evidence of re-activation. In the 3rd case, PCR results in peripheral blood were positive from the day before transplantation, followed by positive results in EMB and sub-cutaneous chagomas biopsy specimens. Only 1 patient had positive Strout results for parasites in skin lesions, and none showed amastigotes in the biopsy specimens. After clinical diagnosis, all patients received 5 mg/kg/day benzimidazole for 6 months, with acceptable tolerance and good clinical outcome. All patients had negative peripheral blood PRC results after 30 days of treatment. One patient had intermittent positive PCR results during follow-up, with no evidence of clinical re-activation.


CONCLUSIONS
Polymerase chain reaction detection of T Cruzi in heart transplant recipients is a more sensitive and specific procedure in diagnosing Chagas' disease re-activation.
Maldonado
Cecilia
C
Molecular Diagnosis Laboratory, Fundación para el Progreso de la Medicina, Córdoba, Argentina.
Albano
Susana
S
Vettorazzi
Lorena
L
Salomone
Oscar
O
Zlocowski
Juan C
JC
Abiega
Claudio
C
Amuchastegui
Marcos
M
Córdoba
Roque
R
Alvarellos
Teresita
T
D000818:Animals; D002598:Chagas Cardiomyopathy / Q000175:diagnosis* / Q000601:surgery; D005260:Female; D016027:Heart Transplantation; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012008:Recurrence; D012680:Sensitivity and Specificity; D014349:Trypanosoma cruzi / Q000302:isolation & purification*
D007166:Immunosuppressive Agents