Perfil de parámetros hematológicos en el HIV pediátrico y los cambios asociados al tratamiento antirretroviral / Hematological parameters profile in pediatric HIV and changes associated with antiretroviral treatment / Perfil de parâmetros hematológicos no HIV pediátrico e as alterações associadas ao tratamento anti-retroviral

Resumen Las alteraciones hematológicas son comunes durante la infección por el virus de la inmunodeficiencia humana (HIV). El objetivo de este trabajo fue describir los perfiles hematológicos e inmunológicos de niños infectados, antes y después de 36 meses de implementado el tratamiento antirretroviral (TARV). Se revisaron historias clínicas de niños expuestos, atendidos en este hospital en el período 2008-2018, con edades entre 6 meses y 14 años. Fueron empleados un contador hematológico (ADVIA 2120), un citómetro de flujo (FACScalibur BD) y una PCR en tiempo real Nuclisens EasyQ (bioMérieux). En 486 historias clínicas se encontraron 58 pacientes sin TARV, 30 por diagnóstico reciente y 28 por adherencia incorrecta o abandono de tratamiento. En ambos grupos se observó disminución porcentual de hemoglobina (Hb) (53% y 43%), volumen corpuscular medio (VCM) (43% y 7%) y LTCD4+ (37% y 57%), respectivamente, sin alteraciones significativas en otros parámetros hematológicos. Veintidós niños con correcta adherencia al TARV incrementaron significativamente los niveles de LTCD4+ (t0:18,8±9%, t1:32,7±6%), Hb (t0:10,9±1,6 g/dL, t1:12,6±1,1g/dL) y VCM (t0:78,7±4,5 fL, t1:101,9±5,6 fL), con disminución simultánea de la carga viral (CV) (t0:4,4±0,75 log t1:<1,70 log) después del seguimiento. La disminución de Hb observada aproximadamente en el 50% de los pacientes sin TARV estaría asociada a la acción viral y al tiempo de evolución de la infección. El incremento en los niveles, asociados a macrocitosis, se relacionaría con el aumento de LTCD4+ y disminución de la CV.

Abstract Hematologic abnormalities are common during human immunodeficiency virus (HIV) infection. Our aim was to describe hematological and immunological profiles present in antiretroviral treatment (ART)-naïve infected children and the changes observed after 36 months of ART initiation. Medical records of exposed children attended at this hospital in the 2008-2018 period were reviewed. Children between 6 months and 14 years were included. An automated blood analyser ADVIA 2120, a FACScalibur BD flow cytometer, and a Nuclisens EasyQ bioMérieux real-time PCR were used to determine different parameters. In 486 medical records evaluated, 58 patients ART-naïve were found, 30 due to recent diagnosis and 28 for incorrect adherence or abandoned treatment. In both groups, a percentage decrease in hemoglobin (Hb) (53% and 43%), mean corpuscular volume (MCV) (43% and 7%) and LTCD4+ (37% and 57%) levels respectively, was observed, without significant alterations in other hematological parameters. Twenty-two children with ART correct adherence increased significantly CD4+T cells (t0:18.8±9%, t1:32.7±6%), Hb (t0:10.9±1.6 g/dL, t1:12.6±1.1 g/dL) and MCV (t0:78.7±4.5 fL, t1:101.9±5.6 fL) levels, with simultaneous decrease of viral load (VL), (t0:4.4±0.75 log, t1:<1.70 log), after 36 months of follow-up. The reduction in Hb levels observed in 50% approximately of patients without ART would be associated with viral action and time of evolution of the infection. The increase in Hb levels and an associated macrocytosis would be related to the CD4+ T cells increase and VL decrease.

Resumo Alterações hematológicas são comuns durante a infecção pelo vírus da imunodeficiência humana (HIV). Nosso objetivo foi descrever os perfis hematológicos e imunológicos em crianças infectadas, antes e após 36 meses de implementar o tratamento antirretroviral (TARV). Foram revisados os prontuários das crianças expostas atendidas neste hospital no período 2008-2018, com idade entre 6 meses e 14 anos. Um contador hematológico (ADVIA 2120), um citômetro de fluxo (FACScalibur BD) e um PCR em tempo real Nuclisens EasyQ (bioMérieux), foram usados. Em 486 prontuários foram encontrados 58 pacientes livres de TARV, 30 por diagnóstico recente e 28 por adesão incorreta ou abandono do tratamento. Em ambos os grupos, observou-se diminuição percentual de hemoglobina (Hb) (53% e 43%), volume corpuscular médio (VCM) (43% e 7%) e LTCD4+ (37% e 57%), respectivamente, sem alterações significativas nos demais parâmetros hematológicos. Vinte e duas crianças com adesão correta ao TARV aumentaram significativamente os níveis de LTCD4+ (t0:18,8±9%, t1:32,7±6%), Hb (t0:10,9±1,6 g/dL, t1:12,6±1,1 g/dL) e VCM (t0:78,7±4,5 fL, t1:101,9±5,6 fL), com diminuição simultânea da carga viral (CV) (t0:4,4±0,75 log, t1:<1,70 log), depois do seguimento. A diminuição dos níveis de Hb observada em aproximadamente 50% dos pacientes sem TARV estaria associada à ação viral e ao tempo de evolução da infecção. O aumento nos níveis, associados a macrocitose, estaria relacionado com o aumento de LTCD4+ e diminuição da CV.

Modulation of Trypanosoma cruzi-specific T-cell responses after chemotherapy for chronic Chagas disease

The aim of this review is to describe the contributions of the knowledge of T-cell responses to the understanding of the physiopathology and the responsiveness to etiological treatment during the chronic phase of Chagas disease. T-helper (Th)1 and interleukin (IL)-10 Trypanosoma cruzi-specific T-cells have been linked to the asymptomatic phase or to severe clinical forms of the disease, respectively or vice versa, depending on the T. cruzi antigen source, the patient’s location and the performed immunological assays. Parasite-specific T-cell responses are modulated after benznidazole (BZ) treatment in chronically T. cruzi-infected subjects in association with a significant decrease in T. cruzi-specific antibodies. Accumulating evidence has indicated that treatment efficacy during experimental infection with T. cruzi results from the combined action of BZ and the activation of appropriate immune responses in the host. However, strong support of this interaction in T. cruzi-infected humans remains lacking. Overall, the quality of T-cell responses might be a key factor in not only disease evolution, but also chemotherapy responsiveness. Immunological parameters are potential indicators of treatment response regardless of achievement of cure. Providing tools to monitor and provide early predictions of treatment success will allow the development of new therapeutic options.

Evaluación inmunológica del tratamiento con benznidazol en la enfermedad de Chagas crónica / Immunological Assessment of Benznidazol Therapy in Chronic Chagas Disease

Para determinar el efecto del tratamiento con benznidazol sobre las células T de memoria específica para Trypanosoma cruzi, se seleccionaron 47 pacientes con tres reacciones serológicas positivas para T. cruzi, sin cardiopatía y edades comprendidas entre los 30 y los 50 años. El tratamiento se realizó con benznidazol en dosis de 5 mg/kg/d por 30 días. Se efectuó una evaluación serológica, inmunológica y clínica pretratamiento (tiempo 0) y a los 2, 6 y 12 meses postratamiento. Posteriormente, los controles se hicieron anualmente. La respuesta de linfocitos T frente a un lisado de amastigotas de T. cruzi se evaluó por la técnica de ELISPOT para IFN-ã. La frecuencia de linfocitos T de memoria productores de IFN-ã específicos para T. cruzi disminuyó significativamente en el grupo tratado (n = 33) versus el no tratado (n = 14) 12 meses después del seguimiento. Once de 25 (44%) pacientes que recibieron benznidazol negativizaron la respuesta para IFN-ã. Cuatro de los 11 (36%) pacientes con ELISPOT (+) que negativizaron la respuesta por ELISPOT para IFN-ã también negativizaron la serología convencional a los 2 años postratamiento. Durante el seguimiento no se observaron alteraciones clínicas. Estos hallazgos muestran que el benznidazol es capaz de modular la respuesta celular T de memoria específica para T. cruzi. La medición de la frecuencia de linfocitos T de memoria productores de IFN-ã podría constituir un ensayo más sensible y precoz para determinar el impacto/eficacia del tratamiento específico contra este parásito.

To determine the effect of benznidazol therapy on memory T cells specific for Trypanosoma cruzi, 47 patients between 30 and 50 years old and three positive serological tests for T. cruzi without cardiopathy were selected. Benznidazol was administered in a dose of 5 mg/kg/d during 30 days. Serological, immunological and clinical assessment was performed at basal (time 0) and at 2, 6 and 12 months following treatment, and once a year thereafter. IFN-ã ELISPOT assay was used to evaluate T cell responses against a T. cruzi lysate obtained from amastigotes. The frequency of IFN-ã - producing memory T lymphocytes specific for T. cruzi was significantly lower in the treatment group (n=33) compared to the control group (n=14) 12 months after the therapy. IFN- ã response became negative in 11 patients in the treatment group (44%). Among these 11 patients, conventional serology also became negative in 4 patients (36%) after 2 years of treatment. No clinical manifestations occurred during follow-up. These findings show that benznidazol is capable of modulating T cell responses specific for T. cruzi. Measuring the frequency of memory T lymphocytes producing IFN-ã might become a more sensitive test to determine earlier the impact and/or efficacy of the specific treatment against this parasite.