Description of the characteristics of patients with diseases associated with immunosuppression and Cryptosporidium spp. infection seen at a referral children's hospital in Argentina, 2018-2023. / Caracterización de pacientes con enfermedades asociadas a inmunosupresión con infecciones por Cryptosporidium spp. atendidos en un hospital pediátrico referencial de Argentina, 2018-2023.

Cryptosporidium spp. is a diarrhea-causing protozoan. Immunocompromised patients may develop severe and persistent clinical forms. Here we describe the characteristics of patients with an underlying disease associated with immunosuppression (DAI) and Cryptosporidium spp. infection seen at a referral children's hospital in Argentina between 2018 and 2023. Demographic data, DAI, diarrhea characteristics, and co-infections were analyzed. A total of 30 patients with DAI and cryptosporidiosis were included. Most of them had undergone a solid organ transplant, had a hematologic neoplasm, or primary immunodeficiency. Persistent diarrhea was observed in 18 patients at the time of diagnosis. Co-infections were recorded in 6 patients. Cryptosporidiosis should be considered in the differential diagnosis of acute or persistent diarrhea in children with different types of DAI, such as solid organ transplant, hematologic neoplasms, and primary immunodeficiencies.

Cryptosporidium spp. es un protozoario productor de diarrea. Los pacientes inmunocomprometidos pueden desarrollar formas clínicas graves y persistentes. Se describen las características de pacientes con enfermedad de base asociada a inmunosupresión (EAI) con infección por Cryptosporidium spp. (IC) atendidos en un hospital pediátrico referencial de Argentina entre los años 2018 y 2023. Se analizaron datos demográficos, EAI, características de la diarrea y coinfecciones. Se incluyeron 30 pacientes con EAI e IC. La mayoría registró trasplante de órgano sólido, neoplasia hematológica e inmunodeficiencia primaria. Dieciocho presentaron diarrea persistente al momento del diagnóstico. Seis pacientes registraron coinfecciones. Se debe considerar la criptosporidiosis en el diagnóstico diferencial de enfermedad diarreica aguda o persistente en niños con distintos tipos de EAI, como el trasplante de órgano sólido, neoplasias hematológicas e inmunodeficiencias primarias.

Enterocytozoon bieneusi Infection after Hematopoietic Stem Cell Transplant in Child, Argentina.

We report a case of Enterocytozoon bieneusi infection in a pediatric hematopoietic stem cell transplant recipient in Argentina. Spores were visualized in feces using Calcofluor White and modified trichrome stainings. PCR and sequencing identified E. bieneusi genotype D in fecal samples and liver samples, confirming extraintestinal dissemination of the parasite.

Prevalencia de parásitos intestinales en muestras de pacientes atendidos en el Hospital de Pediatría "Prof. Dr. Juan P. Garrahan", Argentina, 2018-2019 / Prevalence of intestinal parasites in samples of patients attending the Hospital de Pediatría "Prof. Dr. Juan P. Garrahan", Argentina, 2018-2019 / Prevalência de parasitas intestinais em amostras de pacientes atendidos no Hospital de Pediatría "Prof. Dr. Juan P. Garrahan", Argentina, 2018-2019

Resumen Se evaluaron retrospectivamente los resultados obtenidos de estudios parasitológicos en muestras de heces y escobillados anales remitidos al Laboratorio de Parasitología y Gastroenterología del Hospital de Pediatría "Prof. Dr. Juan P. Garrahan" de la Ciudad de Buenos Aires, Argentina. El objetivo del trabajo fue conocer la prevalencia de los parásitos intestinales observados en las muestras remitidas a este hospital y su distribución en rangos etarios. En el período comprendido entre mayo de 2018 y abril de 2019 se analizó un total de 4713 muestras pertenecientes a 3311 pacientes, que arrojó un resultado total de 29% de positivos (1371/4713). De los exámenes coproparasitológicos el 30% fueron positivos (1193/4025) y se hallaron huevos de Enterobius vermicularis en el 26% (178/688) de los escobillados anales. En las muestras seriadas de heces se obtuvo un 37% de positividad mientras que en muestras únicas un 21%. En la totalidad de muestras fecales, los enteroparásitos más prevalentes fueron Blastocystis spp. en un 14% (579/4025), Giardia duodenalis 11% (456/4025) y Dientamoeba fragilis 7% (291/4025). Los resultados demostraron diferencias significativas con mayor prevalencia de parásitos intestinales en pacientes en edad escolar comprendidos entre los 6 y 10 años, en relación a los de edad preescolar. En las muestras fecales analizadas se evidenció un predominio de parasitismo de protozoos sobre helmintos, por lo que se debería considerar reforzar el diagnóstico de laboratorio de esas especies mediante técnicas, como coloraciones, que posibiliten su hallazgo y confirmación.

Abstract The results obtained of the coproparasitological studies and anal swab submitted to the laboratory of the Parasitology Section of the Hospital de Pediatría "Prof. Dr. Juan P. Garrahan" of the Buenos Aires City, Argentina, were retrospectively evaluated The aim of this study was to determine the prevalence of intestinal parasites found on the submitted samples and to evaluate their frequency according to the age of the patients. Within the period between May 2018 and April 2019, a total of 4713 samples corresponding to 3311 patients were analyzed and intestinal parasites were present in 29% (1371/4713). In 30% of coproparasitological studies parasite estructures were found (1193/4025) and 26% of anal swab samples were positive for the presence of Enterobius vermicularis eggs (178/688). In serial fecal samples, 37% positive results were obtained, while in single samples, 21%. The most prevalent enteroparasites calculated from the total fecal samples were: Blastocystis spp. with 14% (579/4025), followed by Giardia duodenalis 11% (456/4025) and Dientamoeba fragilis 7% (291/4025). The incidence of intestinal parasites was higher in the group of patients between 6 and 10 years, and the existence of significant differences between proportions of parasitized patients in preschool and school infants, was observed. In the faecal samples analyzed, a greater prevalence of parasitism caused by protozoa than by helminths was evidenced, for which reason it should be considered, reinforcing the laboratory diagnosis using techniques such as stains that allow its finding and confirmation.

Resumo Os resultados obtidos de estudos parasitológicos em amostras fecais e esfregaços anais enviados ao Laboratório de Parasitologia e Gastroenterologia do Hospital de Pediatría "Prof. Dr. Juan P. Garrahan" da Cidade de Buenos Aires, Argentina, foram avaliados retrospectivamente. O objetivo do estudo foi avaliar a prevalência dos parasitas intestinais observados nas amostras enviadas a este hospital e sua distribuição por faixas etárias. Durante o período compreendido entre maio de 2018 a abril de 2019 foram analisadas 4713 amostras, correspondentes a 3311 pacientes, o que deu um resultado total de 29% de positivos (1371/4713). 30% dos exames coproparasitológicos foram positivos (1193/4025) e foram encontrados ovos de Enterobius vermicularis em 26% (178/688) dos esfregaços anais. Nas amostras seriadas fecais foram obtidos 37% de resultados positivos, enquanto que em amostras únicas, 21%. Os enteroparasitas mais prevalentes na totalidade das amostras fecais foram Blastocystis spp. em 14% (579/4025), Giardia duodenalis 11% (456/4025) e Dientamoeba fragilis 7% (291/4025). Os resultados demonstraram diferenças significativas com maior prevalência de parasitas intestinais em pacientes em idade escolar da faixa etária entre 6 e 10 anos, em relação aos da pré-escola. Nas amostras fecais analisadas, evidenciou-se um predomínio de parasitismo por protozoários por sobre helmintos, pelo qual deve ser considerado o reforço do diagnóstico laboratorial dessas espécies por meio de técnicas, como colorações que permitam a sua localização e confirmação.

Neuropeptide Kyotorphin Impacts on Lipopolysaccharide-Induced Glucocorticoid-Mediated Inflammatory Response. A Molecular Link to Nociception, Neuroprotection, and Anti-Inflammatory Action.

Neuropeptide kyotorphin (KTP) is a potent analgesic if administered directly into the brain. In contrast, KTP-amide (KTP-NH2) is analgesic, neuroprotective, and anti-inflammatory following systemic administration, albeit its mechanism of action is unknown. The aim of this study was to shed light on the mechanism of action of KTP-NH2 at the molecular level. KTP-NH2 does not inhibit the enkephalinases angiotensin-converting-enzyme and dipeptidyl-peptidase 3. Intravital microscopy showed that KTP-NH2 decreased the number of rolling leukocytes in a mouse model of inflammation induced by lipopolysaccharide (LPS). Pretreatment with metyrapone abrogated the action of KTP-NH2. Interestingly, stimulating rolling leukocytes using CXCL-1 is also counteracted by the KTP-NH2, but this effect is not abrogated by metyrapone. We conclude that KTP-NH2 has dual action: a glucocorticoid-mediated action, which is dominant in the full-fledged LPS-induced inflammation model, and a glucocorticoid-independent mechanism, which is predominant in models in which leukocyte rolling is stimulated but inflammation is not totally developed.

Endothelium-Mediated Action of Analogues of the Endogenous Neuropeptide Kyotorphin (Tyrosil-Arginine): Mechanistic Insights from Permeation and Effects on Microcirculation.

Kyotorphin (KTP) is an endogenous peptide with analgesic properties when administered into the central nervous system (CNS). Its amidated form (l-Tyr-l-Arg-NH2; KTP-NH2) has improved analgesic efficacy after systemic administration, suggesting blood-brain barrier (BBB) crossing. KTP-NH2 also has anti-inflammatory action impacting on microcirculation. In this work, selected derivatives of KTP-NH2 were synthesized to improve lipophilicity and resistance to enzymatic degradation while introducing only minor changes in the chemical structure: N-terminal methylation and/or use of d amino acid residues. Intravital microscopy data show that KTP-NH2 having a d-Tyr residue, KTP-NH2-DL, efficiently decreases the number of leukocyte rolling in a murine model of inflammation induced by bacterial lipopolysaccharide (LPS): down to 46% after 30 min with 96 µM KTP-NH2-DL. The same molecule has lower ability to permeate membranes (relative permeability of 0.38) and no significant activity in a behavioral test which evaluates thermal nociception (hot-plate test). On the contrary, methylated isomers at 96 µM increase leukocyte rolling up to nearly 5-fold after 30 min, suggesting a proinflammatory activity. They have maximal ability to permeate membranes (relative permeability of 0.8) and induce long-lasting antinociception.

Pharmacological Potential of the Endogenous Dipeptide Kyotorphin and Selected Derivatives.

The endogenous peptide kyotorphin (KTP) has been extensively studied since it was discovered in 1979. The dipeptide is distributed unevenly over the brain but the majority is concentrated in the cerebral cortex. The putative KTP receptor has not been identified yet. As many other neuropeptides, KTP clearance is mediated by extracellular peptidases and peptide transporters. From the wide spectrum of biological activity of KTP, analgesia was by far the most studied. The mechanism of action is still unclear, but researchers agree that KTP induces Met-enkephalins release. More recently, KTP was proposed as biomarker of Alzheimer disease. Despite all that, KTP limited pharmacological value prompted researchers to develop derivatives more lipophilic and therefore more prone to cross the blood-brain barrier (BBB), and also more resistant to enzymatic degradation. Conjugation of KTP with functional molecules, such as ibuprofen, generated a new class of compounds with additional biological properties. Moreover, the safety profile of these derivatives compared to opioids and their efficacy as neuroprotective agents greatly increases their pharmacological value.

Using mobile technology to conduct epidemiological investigations.

INTRODUCTION: The aim of this study was to report the experience of an epidemiological field survey for which data were collected and analyzed using tablets. METHODS: The devices used Epi Info 7 (Android version), which has been modeled a database with variables of the traditional form. RESULTS: Twenty-one households were randomly selected in the study area; 75 residents were registered and completed household interviews with socioeconomic and environmental risk variables. CONCLUSIONS: This new technology is a valuable tool for collecting and analyzing data from the field, with advantageous benefits to epidemiological surveys.

Differential effects of mycophenolate mofetil and cyclosporine A on peripheral blood and cord blood natural killer cells activated with interleukin-2.

BACKGROUND AIMS: Graft-versus-host disease remains a major cause of death after hematopoietic stem cell transplantation. Cyclosporine (CsA) and mycophenolate mofetil (MMF) have been successfully used alone or in combination as prophylaxis for graft-versus-host disease. Although the effects of these drugs on T cells have been studied, little is known about the effects of both drugs on natural killer (NK) cells. We examined if the sensitivity of umbilical cord blood (CB) NK cells to MMF and/or CsA differs from their adult counterparts. METHODS: An approach that was based on flow cytometry and real-time polymerase chain reaction was used to assess the effects of MMF, CsA and the combination of both drugs on the viability, activation, proliferation and cytotoxicity of peripheral blood (PB) and CB NK cells after culture with interleukin-2. RESULTS: MMF alone or together with CsA induced cell death of CB NK cells but not of PB NK cells. MMF and CsA had differential effects on NK cell activation but significantly reduced proliferation of CB NK cells. MMF reduced perforin expression by PB NK cells, whereas CsA alone or together with MMF drastically decreased degranulation of CB and PB NK cells. However, neither affected cytokine secretion by PB and CB NK cells. CONCLUSIONS: This study showed that CB NK cells were more sensitive to MMF and CsA than were PB NK cells. MMF and CsA had significant effects on NK cells that could jeopardize the beneficial effects of NK cells after hematopoietic stem cell transplantation.