Benznidazole in Cerebrospinal Fluid: a Case Series of Chagas Disease Meningoencephalitis in HIV-Positive Patients.

Chagas disease reactivation in HIV-positive people is an opportunistic infection with 79 to 100% mortality. It commonly involves the central nervous system (CNS). Early treatment with trypanocidal drugs such as benznidazole (BNZ) is crucial for this severe manifestation of Trypanosoma cruzi infection. However, limited BNZ clinical pharmacology data are available, especially its concentration in the CNS. We report a series of HIV-positive patients undergoing treatment for T. cruzi meningoencephalitis, their clinical response, and cerebrospinal fluid (CSF) and plasma BNZ concentrations. Measurements were carried out using leftover samples originally obtained for routine medical care. A high-performance liquid chromatography/tandem mass spectrometry bioanalytical method designed for BNZ plasma measurements was adapted and validated for CSF samples. Six patients were enrolled in this study from 2015 to 2019. A total of 6 CSF and 19 plasma samples were obtained. Only three of the CSF samples had detectable BNZ levels, all under 1 µg/ml. Fifteen plasma samples had detectable BNZ, and 13 were above 2 µg/ml, which is the putative trypanocidal level. We observed BNZ concentrations in human CSF and plasma. CSF BNZ concentrations were low or not measurable in all patients, suggesting that the usual BNZ doses may be suboptimal in HIV-positive patients with T. cruzi meningoencephalitis. While drug-drug and drug-disease interactions may be in part responsible, the factors leading to low CSF BNZ levels remain to be studied in detail. These findings highlight the potential of therapeutic drug monitoring in BNZ treatment and suggest that the use of higher doses may be useful for Chagas disease CNS reactivations.

A simple and efficient HPLC method for benznidazole dosage in human breast milk.

BACKGROUND: Due to migration, Chagas disease is a significant public health problem in Latin America, and in other nonendemic regions. The 2 drugs currently available for the treatment, nifurtimox and benznidazole (BNZ), are associated with a high risk of toxicity in therapeutic doses. Excretion of drug into human breast milk is a potential source of unwanted exposure and pharmacologic effects in the nursing infant. However, this phenomenon was not evaluated until now, and measurement techniques for both drugs in milk were not developed. METHODS: In this work, we described the development of a simple and fast method to quantify BNZ in human milk using a pretreatment that involves acid protein precipitation followed by tandem microfiltration, and reverse phase high-performance liquid chromatography/ultraviolet analysis. It is simple because it takes only 3 steps to obtain a clean extracted solution that is ready to inject into the high-performance liquid chromatography equipment. It is fast because a complete analysis of a sample takes only 36 minutes. RESULTS: Although the human breast milk composition is very variable, and lipids are one of the most difficult compounds to clean up on a milk sample, the procedure has proven to be robust and sensitive with a limit of detection of 0.3 µg/mL and quantization of 0.9 µg/mL. Despite a 70% recovery value, which could be considered a relatively low result, this recovery is reproducible (coefficient of variation <10%) and the analytical response under the linear range is very good (r = 0.9969 adjusted). Real samples of human breast milk from patients in treatment with BNZ were dosed to support the validation process of the method. CONCLUSIONS: The method described is fast, specific, accurate, precise, and sufficiently sensitive in the clinical context for the quantification of BNZ in human milk. For all these reasons, it is suitable for clinical risk evaluation studies.

Evaluación de los protocolos de tratamiento vigentes para la administración de antichagásicos a madres lactantes / Evaluation of current treatment protocols for the administration of antichagasic drugs to breastfeeding mothers

INTRODUCCIÓN Diferentes estudios evalúan la pertinencia de los protocolos actualmente vigentes para el tratamiento del Chagas en madres lactantes. Es necesario abordar tanto la validación de una técnica analítica para la detección y el dosaje del fármaco antichagásico benznidazol (BNZ) en leche materna, como la recolección de muestras de interés clínico para el dosaje de la misma droga. OBJETIVOS Aportar al estudio de la transferencia de drogas antichagásicas hacia la leche materna para definir riesgos potenciales, o ausencia de ellos, para los lactantes de madres con enfermedad de Chagas que reciban tratamiento con esta droga y deseen continuar con la lactancia. MÉTODOS Para el desarrollo de las técnicas de laboratorio se trabajó con muestras blanco de la matriz biológica a estudiar (leche). Se realizaron dosajes in vitro y ensayos de robustez del método seleccionado con una de las drogas en estudio (BZN). Con el método validado, se trabajó con muestras reales de madres que amamantaban y que habían sido medicadas únicamente con BZN. RESULTADOS Los ensayos de robustez realizados a la técnica de extracción de BZN en leche materna revelaron una ausencia de correlación entre la medida del contenido lipídico/lipoproteico y el grado de recuperación en la extracción del fármaco. Los dosajes de leche de madres lactantes mostraron un nivel de exposición pediátrica máxima igual al 17% de la mayor dosis terapéutica utilizada en pediatría (8 mg/kg/día). DISCUSIÓN os resultados hallados en los dosajes en leche de madres bajo terapia con BNZ denotan una baja probabilidad de exposición a niveles elevados de la droga a través de esta vía. Esto indicaría la pertinencia del tratamiento del Chagas en estas pacientes, lo que sugiere una modificación de los protocolos vigentes.