Frequency of strongyloidiasis and associated factors: Analysis of 13 years of laboratory results in a tertiary referral hospital in Honduras, 2010-2022

Introduction. The frequency of detected strongyloidiasis is affected by the selected laboratory method in the studied population. Considering that Honduras has few community-based studies, the analysis of the laboratory record data can provide information helping to understand this parasitosis. Objective. To estimate the frequency and to identify the factors associated with strongyloidiasis, analyzing the laboratory records of the Servicio de Parasitología at Hospital Escuela in Tegucigalpa (Honduras) between 2010 and 2022. Materials and methods. We carried out a descriptive, cross-sectional, analytical study. The laboratory diagnosis consisted of stool samples' examination by direct smear and modified Baermann technique. We estimated frequencies and percentages. The statistical association was calculated with prevalence ratios and a 95% confidence interval. Software R, version 4.2.0, and epiR package, version 2.0.46, were used to perform the analysis. Results. The frequency of strongyloidiasis was 0.29% (112/38,085). It was higher with the modified Baermann technique (0.87%; 40/4,575) among male patients (0.44%; 70/15,758). Regarding the age, strongyloidiasis was higher in the 20-40 years old group (0.41%; 28/6,886) with direct smear and 41-61 years old (1.14%; 14/1,232) group with the modified Baermann technique. Among the factors associated with strongyloidiasis were age between 20 and 61 years old (PR=2.26, CI 95%=1.53-3.31), male patients (PR=2.34, CI 95%=1.60-3.44), mucus (PR=1.86, CI 95%=1.22-2.83) and Charcot-Leyden crystals in stool (PR=8.47, CI 95%=5.14-13.96); watery stool (PR=2.39, CI 95%=1.55-3.68), and other helminthiases (PR=6.73, CI 95%=3.98-11.38). Associated factors to cases detected with the modified Baermann technique were outpatient consultation (PR=4.21, CI 95%=1.91-9.28) and formed stools (PR=3.99, CI95% =1.94-8.19). Conclusions. The modified Baermann technique increased the detection of strongyloidiasis almost four times. Most cases were distributed among male adults. The cases diagnosed exclusively with the modified Baermann technique have differences from those with observed larvae in the direct smear. It is necessary to develop community-based population studies.

Introducción. La detección de estrongiloidiasis depende del método de diagnóstico utilizado y la población estudiada. Dado que en Honduras hay pocos estudios poblacionales, el análisis de los datos de laboratorio puede generar información que ayude a entender esta parasitosis. Objetivo. Estimar la frecuencia e identificar los factores asociados a la estrongiloidiasis mediante el análisis de los registros de laboratorio del Servicio de Parasitología del Hospital Escuela en Tegucigalpa (Honduras) durante el periodo 2010-2022. Materiales y métodos. Se llevó a cabo un estudio descriptivo, transversal y analítico. El diagnóstico de laboratorio consistió en el análisis de muestras de heces con los métodos directo y Baermann modificado. Se estimaron frecuencias y porcentajes, y la asociación estadística se calculó con razón de prevalencia e intervalos de confianza del 95 %. Se utilizaron los programas R, versión 4.2.0, y el paquete epiR, versión 2.0.46, para ejecutar los análisis estadísticos. Resultados. La frecuencia general de estrongiloidiasis fue 0,29 % (112/38.085). Dicha frecuencia de detección fue mayor con el método de Baermann modificado (0,87 %; 40/4.575), entre pacientes masculinos (0,44 %; 70/15.758). También fue mayor en el rango de edad 20-40 años (0,41%; 28/6.886) por examen directo y entre los 41-61 años (1,14%; 14/1.232) con el método de Baermann modificado. Entre los factores asociados con la estrongiloidiasis se encontraron: edad entre los 20 y los 61 años (RP=2,26; IC 95%=1,53-3,31), sexo masculino (RP=2,34; IC95%=1,60-3.44), moco (RP=1,86; IC 95%=1,22-2,83) y cristales de Charcot-Leyden en heces (RP=8,47, IC 95%=5,14-13,96), heces líquidas (RP=2,39, IC 95%=1,55-3,68) y otras helmintiasis (RP=6,73, IC 95%=3,98-11,38). Como factores asociados a los casos detectados con el método de Baermann modificado están consulta externa (RP=4,21, IC 95%=1,91-9,28) y heces formadas (RP=3,99, IC 95%=1,94-8,19). Conclusiones. El método de Baermann modificado aumentó la frecuencia de detección de estrongiloidiasis casi cuatro veces. La mayoría de los casos se distribuyeron entre pacientes masculinos adultos. Los casos diagnosticados exclusivamente con el método de Baermann modificado tuvieron diferencias con los casos diagnosticados por examen directo. Es necesario realizar estudios poblacionales.

Could the acute strongyloides venezuelensis infection cause non-reversible host morphological changes? / A infecção aguda por strongyloides venezuelensis pode causar alterações morfológicas irreversíveis no hospedeiro? / ¿Puede la infección aguda por las strongyloides venezuelensis causar cambios morfológicos irreversibles en el hostal?

Although research has investigated the host-parasite relationship in Strongyloides venezuelensis infection in the scope of its immunological implications, the morphological consequences of this response for the host organism are yet to be explored. Our objective was to perform an organ morphometric analysis in Wistar rats infected with the intestinal parasite Strongyloides venezuelensis compared with infected rats treated with ivermectin. Twenty-six animals composed three groups: control (non-infected), infected (infected with 2,000 Strongyloides venezuelensis larvae), and infected treated (infected with 2,000 Strongyloides venezuelensis larvae and treated with ivermectin). All rodents were killed 21 days after infection and morphometric analysis of different organs was performed. The results showed significantly higher body and fecal weight in the infected-treated group. The weight of the small intestine increased considerably in the infected group and decreased in the infected-treated group. Pancreas, right kidney, and heart volume increased in the infected group compared with the control group. Despite treatment, the volumes of the stomach, brain, and left kidney increased in both the infected groups compared with the control group indicating the possibility of non- reversible host morphological adaptations. S. venezuelensis infection can augment both, volume and weight of organs ­ not necessarily related to the Strongyloides expulsion process ­ even if the acute infection had been in remission. A potential explanation for these host adaptations, including the occurrence of organ plasticity, are briefly discussed. The following steps encompass a histological analysis to verify the occurrence of hypertrophy/hyperplasia and observe if such morphological alterations remain after infection.

Embora pesquisas tenham investigado a relação parasita-hospedeiro na infecção por Strongyloides venezuelensis no âmbito de suas implicações imunológicas, as consequências morfológicas dessa resposta para o organismo hospedeiro ainda precisam ser exploradas. Nosso objetivo foi realizar uma análise morfométrica de órgãos em ratos Wistar infectados com o parasito intestinal Strongyloides venezuelensis em comparação com ratos infectados tratados com ivermectina. Vinte e seis animais compuseram três grupos: controle (não infectados), infectados (infectados com 2.000 larvas de Strongyloides venezuelensis) e tratados infectados (infectados com 2.000 larvas de Strongyloides venezuelensis e tratados com ivermectina). Todos os roedores foram sacrificados 21 dias após a infecção e a análise morfométrica de diferentes órgãos foi realizada. Os resultados mostraram peso corporal e fecal significativamente maior no grupo tratado infectado. O peso do intestino delgado aumentou consideravelmente no grupo infectado e diminuiu no grupo infectado tratado. O volume do pâncreas, rim direito e coração aumentou no grupo infectado em comparação com o grupo controle. Apesar do tratamento, os volumes do estômago, cérebro e rim esquerdo aumentaram em ambos os grupos infectados em comparação com o grupo controle, indicando a possibilidade de adaptações morfológicas não reversíveis do hospedeiro. A infecção por S. venezuelensis pode aumentar tanto o volume quanto o peso dos órgãos ­ não necessariamente relacionado ao processo de expulsão de Strongyloides ­ mesmo que a infecção aguda estivesse em remissão. Uma possível explicação para essas adaptações do hospedeiro, incluindo a ocorrência de plasticidade de órgãos, é brevemente discutida. As etapas a seguir compreendem uma análise histológica para verificar a ocorrência de hipertrofia/hiperplasia e observar se tais alterações morfológicas permanecem após a infecção.

Aunque la investigación ha investigado la relación parásito-huésped en la infección con Strongyloides venezuelensis dentro del alcance de sus implicaciones inmunológicas, aún deben explorarse las consecuencias morfológicas de esta respuesta para el organismo huésped. Nuestro objetivo fue realizar un análisis morfométrico de órganos en ratas Wistar infectadas con el parásito intestinal Strongyloides venezuelensis en comparación con ratas infectadas tratadas con ivermectina. Veintiséis animales conformaron tres grupos: control (no infectado), infectados (infectados con 2.000 larvas de Strongyloides venezuelensis) y tratados infectados (infectados con 2.000 larvas de Strongyloides venezuelensis y tratados con ivermectina). Todos los roedores fueron sacrificados 21 días después de la infección y se realizó un análisis morfométrico de diferentes órganos. Los resultados mostraron un peso corporal y fecal significativamente mayor en el grupo tratado infectado. El peso del intestino delgado aumentó considerablemente en el grupo infectado y disminuyó en el grupo tratado. El volumen de páncreas, riñón derecho y corazón aumentó en el grupo infectado en comparación con el grupo control. A pesar del tratamiento, los volúmenes de estómago izquierdo, cerebro y riñón aumentaron en ambos grupos infectados en comparación con el grupo control, lo que indica la posibilidad de adaptaciones morfológicas irreversibles del huésped. La infección con S. venezuelensis puede aumentar tanto el volumen como el peso de los órganos -no necesariamente relacionados con el proceso de expulsión de Strongyloides-, incluso si la infección aguda estaba en remisión. Se discute brevemente una posible explicación de estas adaptaciones del huésped, incluida la aparición de plasticidad de los órganos. Los siguientes pasos incluyen un análisis histológico para comprobar la hipertrofia/hiperplasia y para ver si estos cambios morfológicos permanecen después de la infección.

Evaluation of larval surface antigens from infective larvae of Strongyloides venezuelensis for the serodiagnosis of human strongyloidiasis

ABSTRACT Serodiagnosis of strongyloidiasis is usually performed by ELISA for the detection of IgG antibodies due to its high sensitivity and practicality, but its main limitation is a constant source of S. stercoralis antigens. The use of S. venezuelensis as a heterologous source of antigens has facilitated several published studies on the serodiagnosis and epidemiology of human strongyloidiasis. The main objective of this study was to evaluate the diagnostic accuracy of surface cuticle antigens of infective larvae of S. venezuelensis extracted with CTAB detergent (L3-CTAB) in comparison with soluble somatic extracts (L3-SSE) using a panel of sera from immunocompetent and immunocompromised individuals, at three different cut-offs. ROC curve analysis showed that L3-CTAB had an AUC of 0.9926. At the first cut-off value (OD 450 nm = 0.214), sensitivity and specificity were 100% and 90.11%, respectively, with a diagnostic accuracy of 0.93. At a second cut-off value (OD 450 nm = 0.286), sensitivity and specificity were 70% and 100%, respectively, with a diagnostic accuracy of 0.91. However, at an alternative third cut-off value (OD 450 nm = 0.589), sensitivity and specificity were 95% and 97.8%, respectively, with a diagnostic accuracy of 0.97. Using L3-CTAB as an antigenic source, the seropositivity rate in immunocompromised patients was 28.13% (9/32) whereas a seropositivity rate of 34.38% (11/32) was found when L3-SSE was used in ELISA. Therefore, the L3-CTAB is simple and practical to obtain and was found to be highly sensitive and specific.

Strongyloides stercoralis en la médula ósea de una persona que vive con VIH: reporte de caso

Strongyloides stercoralis es un nemátodo que se caracteriza por causar infección intestinal, usualmente asintomática, en pacientes inmunocompetentes. Sin embargo, en aquellos que viven con VIH, y de acuerdo con su estado inmune, puede generar un síndrome de hiperinfección con complicaciones diversas por diseminación a diferentes órganos. Se presenta el caso de un paciente de 30 años con diagnóstico de novo de infección por el virus de la inmunodeficiencia humana, con documentación de enfermedad linfoproliferativa. En los estudios complementarios se documenta la presencia de Strongyloides stercoralis de manera inusual en la médula ósea. A pesar de contar con un recuento de linfocitos T CD4+ mayor a 400 células/ µL y de haberse iniciado el manejo para esta condición con ivermectina, el paciente fallece por un estado séptico asociado al síndrome de hiperinfección, por lo cual se considera que este es un caso inusitado que obliga al clínico a tener en cuenta la presencia del nemátodo en pacientes que viven con VIH.

Summary Strongyloides stercoralis is a nematode that is characterized by causing a usually asymptomatic intestinal infection in immunocompetent individuals. However, in patients living with HIV and depending on their immune status, it can generate a hyperinfection syndrome with various complications due to dissemination to different organs. We present the case of a 30-year-old patient with a de novo diagnosis of human immunodeficiency virus infection and lymphoproliferative disease. Within the laboratory workup, the presence of Strongyloides stercoralis was documented in the bone marrow. Despite having a CD4+ T lymphocyte count greater than 400 cells/microliter and having started treatment for this condition with ivermectin, the patient died due to a septic state associated with hyperinfection syndrome, which is why this is considered an unusual case that alerts the clinician to take into account the presence of the nematode in patients living with HIV.

Evaluation of Strongyloides stercoralis infection in patients with HTLV-1 / Evaluación de la infestación por Strongyloides stercoralis en pacientes con HTLV-1

Introduction: Individuals infected with the human T-lymphotropic virus type 1 (HTLV-1) may present severe and disseminated forms of Strongyloides stercoralis infection with low therapeutic response. Objective: To investigate the S. stercoralis infection and the seroprevalence of IgG anti-S. stercoralis antibodies in individuals infected with HTLV-1 attending the Reference Center for HTLV-1 (CHTLV) in Salvador, Bahia, Brazil. Materials and methods: We conducted a cross-sectional study in 178 HTLV-1-infected individuals treated at the HTLV specialized center between January, 2014, and December, 2018. The parasitological diagnosis of S. stercoralis was performed using the Hoffman, Pons and Janer, agar plate culture, and Baermann-Morais methods. The IgG anti-S. stercoralis detection was performed using an in house enzyme-linked immunosorbent assay (ELISA). The HTLV-1 infection was diagnosed using a commercial ELISA and confirmed by Western blot. Results: The frequency of S. stercoralis infection was 3.4% (6/178). Individuals infected with S . stercoralis from rural areas (50.0%; 3/6) also showed S. stercoralis hyperinfection (>3,000 larvae/gram of feces). The frequency of circulating anti-S. stercoralis IgG antibodies was 20.8% (37/178). Conclusions: HTLV-1-infected people living in precarious sanitary conditions are more prone to develop severe forms of S. stercoralis infection. Considering the high susceptibility and unfavorable outcome of the infection in these individuals, the serological diagnosis for S. stercoralis should be considered when providing treatment.

Introducción. Los individuos infectados por el virus linfotrópico T humano tipo 1 (HTLV-1) pueden presentar formas graves y diseminadas de infestación por Strongyloides stercoralis con poca mejoría terapéutica. Objetivo. Investigar la infestación por S. stercoralis y la seroprevalencia de IgG anti-S. stercoralis en individuos infectados por HTLV-1 atendidos en el Centro de Referencia para HTLV-1 (CHTLV), en Salvador, Bahía, Brasil. Materiales y métodos. Se hizo un estudio transversal con 178 individuos infectados por HTLV-1 atendidos en el centro especializado de HTLV entre enero de 2014 y diciembre de 2018. El diagnóstico parasitológico de S. stercoralis se hizo mediante los métodos de Hoffman, Pons y Janer, cultivo en placa de agar y Baermann-Morais. Para la detección de IgG anti-S. stercoralis, se utilizó una prueba casera de inmunoabsorción ligada a enzimas (ELISA). La infección por HTLV-1 se diagnosticó usando un ELISA comercial y se confirmó mediante Western blot. Resultados. La frecuencia de infestación por S. stercoralis fue del 3,4 % (6/178). Además, los individuos infestados por S. stercoralis provenientes de la zona rural (50,0 %; 3/6) también mostraron hiperinfestación por S. stercoralis (>3.000 larvas/gramo de heces). La frecuencia de anticuerpos IgG anti-S. stercoralis fue del 20,8 % (37/178). Conclusiones. Las personas infectadas por HTLV-1 que viven en condiciones sanitarias precarias son más propensas a desarrollar formas graves de infestación por S. stercoralis. Teniendo en cuenta la gran vulnerabilidad y el resultado desfavorable de la infección en estos individuos, se debe considerar el diagnóstico serológico de S. stercoralis para administrar el tratamiento

Importance of detection of Strongyloides stercoralis DNA in fecal samples from patients with type 2 diabetes mellitus

Abstract Objective: The association between diabetes and Strongyloides infection remains controversial. This study aimed to detect Strongyloides stercoralis DNA in the feces of patients with Diabetes Mellitus type 2 (DM2). Methods: Fecal samples were analyzed via the Lutz, Rugai, and agar plate culture methods. PCR amplification was performed using two targets (PCR-genus and PCR-species) located on the S. stercoralis 18S ribosomal. Results: The positivity for S. stercoralis using parasitological methods was 1.1%. PCR-genus (14.13%) demonstrated a higher positivity than PCR-species (9.78%). Conclusion: The results confirm the greater positivity of the molecular diagnosis in relation to parasitological methods, reinforcing its use as an additional tool for the diagnosis of S. stercoralis infection in patients with DM2 living in endemic areas for this helminthiasis. HIGHLIGHTS Positivity for strongyloidiasis in coproscopic exam was low in diabetic patients. PCR is more sensitive for detecting S. stercoralis infection in diabetic patients. Molecular diagnosis is an important tool for the detection of S. stercoralis.

Vasculitis por IgA (Púrpura de Henoch Schönlein) en un paciente pediátrico con COVID-19 y Estrongiloidiasis / IgA (Henoch Schönlein Purpura) Vasculitis In A Pediatric Patient With COVID-19 And Strongyloidiasis

La vasculitis es una enfermedad rara en los niños, siendo la Vasculitis por IgA su presentación más frecuente. Una condición que se ha asociado al desarrollo de vasculitis es la invasión del endotelio vascular por el Strongyloides stercoralis en casos de hiperinfestación. Otra condición aún poco investigada, es la probable asociación de los procesos tipo vasculitis por IgA con la infección por SARS-CoV-2 y el COVID-19 propiamente. Presentamos el caso de una paciente de cuatro años que cursó con lesiones purpúricas palpables a predominio de miembros inferiores, dolor abdominal agudo, y episodios de hemorragia digestiva alta. Inicialmente catalogado como un posible dengue grave y leptospirosis, pero que clínica y laboratorialmente se asoció a un cuadro de vasculitis por IgA. Fue SARS-CoV-2 IgM e IgG: Reactivo. Y tuvo coproparasitológico en el que se identificó al Strongyloides stercoralis. La sintomatología remitió tras la administración de corticoterapia y la evolución fue favorable.

Vasculitis is a rare disease in children, with IgA Vasculitis being its most common presentation. One condition that has been associated with the development of vasculitis is the invasion of the vascular endothelium by Strongyloides stercoralis in cases of hyperinfestation. Another condition that is not yet under-researched is the likely association of IgA vasculitis-like processes with SARS-CoV-2 and COVID-19 infection itself. It is presented the case of a four-year-old patient who healed with palpable purplish lesions to lower limb predominance, acute abdominal pain, and episodes of high digestive hemorrhage. Initially listed as a possible severe dengue and leptospirosis, but clinically and laboratorially associated with IgA vasculitis. It was SARS-CoV-2 IgM and IgG: Reactive. And in parasitological study was identified Strongyloides stercoralis. Symptomatology subsided after administration of corticotherapy and the evolution was favorable.

Vasculitis por IGA (púrpura de henoch schönlein) en un paciente pediátrico con COVID-19 y estrongiloidiasis. Reporte de caso

La vasculitis es una enfermedad rara en los niños, siendo la Vasculitis por IgA su presentación más frecuente. Una condición aún poco investigada, es la probable asociación de los procesos tipo vasculitis por IgA con la infección por SARS-CoV-2. Se presenta el caso de una paciente de cuatro años que cursó con lesiones purpúricas palpables a predominio de miembros inferiores, dolor abdominal agudo, y episodios de hemorragia digestiva alta. Inicialmente catalogado como un posible dengue grave y leptospirosis, pero que clínica y laboratorialmente se asoció a un cuadro de vasculitis por IgA. Fue SARS-CoV-2 IgM e IgG: Reactivo. Y tuvo coproparasitológico en el que se identificó al Strongyloides stercoralis. La sintomatología remitió tras la administración de corticoterapia y la evolución fue favorable. Como conclusión, se expuso un caso infrecuente en la población pediátrica, probablemente asociado a los efectos y daños aún desconocidos de la COVID-19 en la actual pandemia.

Vasculitis is a rare disease in children, with IgA Vasculitis being its most common presentation. One condition that is not yet under-researched is the likely association of IgA vasculitis-like processes with SARS-CoV-2 infection. It is presented the case of a four-year-old patient who healed with palpable purplish lesions to lower limb predominance, acute abdominal pain, and episodes of high digestive hemorrhage. Initially listed as a possible severe dengue and leptospirosis, but clinically and laboratorially associated with IgA vasculitis. It was SARS-CoV-2 IgM and IgG: Reactive. And in parasitological study was identified Strongyloides stercoralis. Symptomatology subsided after administration of corticotherapy and the evolution was favorable. In conclusion, it was presented a rare case in the pediatric population, probably associated with the still unknown effects and damage of COVID-19 in the current pandemic.

Tratamento farmacológico da estrongiloidíase em pacientes transplantados / Pharmacological treatment of strongilloidiasis in transplanted patients

O objetivo deste artigo foi comparar o uso da ivermectina e do albendazol em pacientes transplantados e relatar os respectivos sucessos terapêuticos nessa população. Foram analisados artigos que abordassem relatos de casos publicados nos últimos 4 anos no PubMed® relacionando os descritores "transplante de órgãos", "estrongiloidíase" e "tratamento". Foram encontrados e analisados dez relatos de caso que abordaram a estrongiloidíase em situa- ção pós-transplante contemplando 13 indivíduos. Desses, cinco (38,5%) utilizaram ambos os medicamentos, dos quais quatro (80%) se curaram, tendo recebido albendazol e ivermectina por via subcutânea (50%) ou albendazol e ivermectina por vias oral/ subcutânea (50%). O paciente que morreu recebeu albendazol e ivermectina por via subcutânea. Sete (53,8%) indivíduos utiliza- ram apenas ivermectina, dos quais três (42,8%) se curaram tendo recebido o medicamento oral (dois pacientes) ou subcutâneo (um paciente); dois (28,6%) morreram recebendo o medicamento via oral, dois (28,6%) usaram profilaticamente via oral e apenas um não manifestou sintomas. Apenas um (7,7%) indivíduo utilizou somente albendazol via oral tendo sobrevivido à infecção. A uti- lização combinada dos medicamentos ivermectina e albendazol parece ter efeito positivo no tratamento da estrongiloidíase. A administração da ivermectina por via subcutânea apresentou resultados promissores, contudo estudos controlados de siner- gia medicamentosa e vias de administração devem ser realizados para efetiva avaliação.

The objective of this article was to compare the use of ivermec- tin and albendazole in transplanted patients and to report the respective therapeutic successes in this population.Articles ad- dressing case reports published in the last 4 years in the PubMed relating the descriptors "organ transplantation", "strongyloidia- sis", and "treatment" were analyzed. Ten case reports addres- sing strongyloidiasis in a post-transplant situation, covering 13 individuals, were found and analyzed. Of these, five (38.5%) used both drugs of which 4 (80%) were cured having received subcu- taneous albendazole and ivermectin (50%) or oral/subcutaneous albendazole and ivermectin (50%). The patient who died received subcutaneous albenzadole and ivermectin. Seven (53.8%) indi- viduals used only ivermectin, of which three (42.8%) were cured having received the oral (2/3) or subcutaneous (1/3) medication, two (28.6%) died receiving the oral medication, and two (28.6%) used oral medication prophylactically, and only one did not show symptoms. Only one (7.7%) individual used only oral albenzadole and survived the infection. The combined use of the drugs iver- mectin and albendazole seems to have a positive effect on the treatment of strongyloidiasis. The administration of subcuta- neous Ivermectin has shown promising results; however, con- trolled studies of drug synergy and administration routes shall be performed for effective evaluation.

Innovative approaches to improve serodiagnosis of Strongyloides stercoralis infection

ABSTRACT Strongyloidiasis is a helminthiasis of neglected condition that has no gold standard parasitological diagnosis due to the intermittent release of larvae in feces. This study aimed to use an scFv (single chain variable fragment) obtained by Phage Display, previously validated to detect immune complexes in serum samples from individuals infected with Strongyloides stercoralis by enzyme-linked immunosorbent assay (ELISA). Now the ability of scFv to detect the immune complexes was verified by immunofluorescence, flow cytometry using magnetic beads and surface plasmon resonance (SPR). As ELISA, the SPR, immunofluorescence and flow cytometry demonstrated the ability of scFv to detect immune complexes in sera from individuals with strongyloidiasis and discriminate them from sera of individuals with other parasitic diseases and healthy individuals. Besides de conventional ELISA, the novel approaches can also be promptly applied as auxiliary diagnostic tools to the existing parasitological method for accurate diagnosis of human strongyloidiasis.

Ivermectina subcutánea en el tratamiento de un síndrome de hiperinfección por Strongyloides stercoralis / Subcutaneous ivermectin for the treatment of the hyperinfection syndrome by Strongyloides stercoralis

La estrongiloidiasis es una enfermedad causada por el nematodo Strongyloides stercoralis, endémico en las regiones rurales de los países tropicales y subtropicales. Los pacientes inmunosuprimidos tienen un mayor riesgo de infección con este parásito y pueden terminar desarrollando un síndrome de hiperinfección que conlleva un alto riesgo de muerte. En el tratamiento se utiliza la ivermectina, pero, ni en Colombia ni en el mundo, existe una presentación parenteral del medicamento para uso en humanos, lo cual es un problema en aquellos pacientes que puedan tener comprometida la absorción intestinal, como es el caso de aquellos con obstrucciones intestinales. Se reporta el caso de un síndrome de hiperinfección por S. stercoralis en Colombia tratado con ivermectina subcutánea; la idea al presentarlo es incentivar los estudios de farmacocinética y farmacodinamia que analicen esta vía de administración como alternativa para el tratamiento de pacientes con riesgo de fracaso terapéutico con la vía oral.

Strongyloidiasis is a disease caused by the nematode Strongyloides stercoralis that is endemic in rural regions in tropical and subtropical countries. Immunosuppressed patients have an increased risk of infection by this parasite and are at risk of developing a hyperinfection syndrome which involves a higher risk of death. The syndrome is treated with ivermectin, however, there is no parenteral presentation of this medication for human use in Colombia or the world, which is an important problem in patients who have compromised enteral absorption, for instance, those with intestinal obstructions. We present a case of hyperinfection syndrome by Strongyloides stercoralis in Colombia, which was treated with subcutaneous ivermectin. Our purpose is to encourage pharmacokinetic and pharmacodynamic studies to establish this route of administration in the future as an alternative for those patients who have a high risk of therapeutic failure with the oral route.

Fatal Strongyloides stercoralis hyperinfection syndrome in an alcoholic diabetic patient from México / Síndrome de hiperinfección mortal por Strongyloides stercoralis en un paciente diabético y alcohólico de México

Strongyloides stercoralis hyperinfection syndrome is a medical emergency that requires a high level of suspicion. Immunocompromised patients are at high risk of hyperinfection syndrome; however, malnutrition, alcoholism, and diabetes mellitus also need to be considered as predisposing factors. The diagnosis and treatment of Strongyloides hyperinfection are challenging and patients often have severe complications. Consequently, mortality is overwhelmingly high, with proportions above 60%. Herein, we report a case of Strongyloides hyperinfection in a 40-year-old alcoholic diabetic patient living in México. Unfortunately, the late diagnosis resulted in his death despite the treatment and supportive measures. Increased awareness is needed to prevent the dire consequences of strongyloidiasis.

El síndrome de hiperinfección por Strongyloides stercoralis es una emergencia médica que requiere una aguda sospecha clínica. Los pacientes inmunocomprometidos tienen alto riesgo de sufrir el síndrome de hiperinfección; sin embargo, la desnutrición, el alcoholismo y la diabetes mellitus también deben considerarse factores predisponentes. El diagnóstico y el tratamiento de la hiperinfección por S. stercoralis constituyen un desafío y los pacientes a menudo tienen complicaciones graves. Como consecuencia, la mortalidad es abrumadoramente alta, con proporciones superiores al 60 %. Se presenta un caso de hiperinfección por S. stercoralis en un paciente diabético y alcohólico de 40 años que vivía en México. Infortunadamente, el diagnóstico tardío causó su muerte a pesar del tratamiento y las medidas de soporte. Se necesita un mayor conocimiento para prevenir las terribles consecuencias de la estrongiloidiasis.

Strongyloides hyperinfection in a patient with solid malignant tumor a case report

Strongyloides stercoralis is unique among the nematodes, in which it completes its life cycle inside a single human host by causing autoinfection in the host, and it causes hyperinfection leading to persistent and fatal disseminated infections in immunocompromised hosts. The present case report is about strongyloidiasis fatal hyperinfection in a patient with malignant tumor of the tongue on radiotherapy treatment, to highlight the need for clinical suspicion of strongyloidiasis in an immunocompromised host. As per the Centers for Disease Control and Prevention, the mortality in strongyloides hyperinfection syndrome is alarmingly high, a case fatality rate that is almost 90%. Hence, the clinicians should be well equipped to diagnose, treat, and also prevent the fatal consequences of this lethal nematode. Detailed workup for this parasitic infection is crucial, and this case report emphasizes that a simple wet mount stool microscopic examination can clinch the diagnosis.

Strongyloides stercoralis hyperinfection in a renal transplant recipient

Strongyloidiasis is a worldwide intestinal infection produced by the nematode Strongyloides stercoralis. In this study, we report the case of a 47-year-old female patient who was submitted to renal transplant and an immunosuppression regimen. She was admitted to the emergency service with intense abdominal pain, evolving to an acute respiratory insufficiency, gram-negative bacteremia, refractory shock and death. S. stercoralis larvae were identified in the parasitological exam and bronchoalveolar lavage. This provides evidence for the importance of the early diagnosis of this neglected helminthiasis in transplanted patients undergoing immunosuppresive therapy

Hemorragia digestiva ocasional em criança por estrongiloidíase: importância do exame parasitológico / Occasional digestive hemorrhage in children due to strongyloidiasis: importance of parasitologic testing

RESUMO Objetivo: Descrever um caso incomum de infecção por Strongyloides stercoralis (S. stercoralis) em paciente de quatro meses de idade e ressaltar a importância do diagnóstico precoce. Descrição do caso: Paciente masculino, procedente e residente de Videira, Santa Catarina, Brasil, nasceu pré-termo, parto cesárea, peso de nascimento 1.655 g, e permaneceu na Unidade de Terapia Intensiva neonatal e intermediária por 20 dias. Aos quatro meses de idade, começou a evacuar fezes sanguinolentas e foi feita hipótese de alergia à proteína do leite de vaca, em razão da sintomatologia e do uso da fórmula infantil para o primeiro semestre, para o qual foi indicada a substituição por fórmula infantil com proteína hidrolisada. Foram solicitados a pesquisa de leucócitos e o exame parasitológico das fezes). Ambos se mostraram positivos e o parasitológico revelou a presença de larva rabditoide de S. stercoralis. O clínico manteve a hipótese inicial e a dieta, mas solicitou a coleta de três amostras de fezes, que resultaram em uma amostra para larvas rabditoide, em muda, de S. stercoralis. Como a criança apresentava dor abdominal, vômito e as fezes permaneciam sanguinolentas, foi iniciado o tratamento com tiabendazol - duas vezes/dia por dois dias -, repetido após sete dias, e, em seguida, realizado o exame parasitológico de fezes, tendo sido negativo. Comentários: A estrongiloidíase, apesar de ser uma infecção parasitária frequentemente leve, em pacientes imunocomprometidos pode se apresentar de forma grave e disseminada. Deve-se suspeitar desse agente em pacientes que vivem em áreas endêmicas, sendo o diagnóstico estabelecido por meio da pesquisa das larvas do S. stercoralis na secreção traqueal e nas fezes.

ABSTRACT Objective: To describe an uncommon case of infection by Strongyloides stercoralis (S. stercoralis) in a 4-month-old child and to highlight the importance of early diagnosis. Case description: The patient was a male child from the city of Videira, State of Santa Catarina, Southern Brazil, who was born preterm by Cesarean-section, weighing 1,655 g, and stayed in the neonatal intensive care unit for 20 days. At four months of age, the child started presenting blood in stools and the possibility of cow's milk protein allergy was considered, given the symptoms and the use of infant formula in his 1st semester of life, which was then replaced by infant formula with hydrolyzed protein. White blood cell count and a parasitological stool sample were requested. Both tested positive and the stool ova and parasite examination showed a rhabditoid larva of S. stercoralis. The clinician maintained the initial hypothesis and diet, but requested three new stool samples, which tested positive for rhabditoid larvae of S. stercoralis. Since the child presented abdominal pain and vomiting, and there was still blood in stools, treatment with thiabendazole was initiated twice a day for two days. Treatment was repeated after seven days along with a new parasitological examination, which was then negative. Comments: Although strongyloidiasis is usually a mild parasitic infection, it may be severe and disseminated in immunocompromised patients. This agent must be considered in patients who live in endemic areas, and the diagnosis should be established by searching S. stercoralis larvae in tracheal secretions and in stools.

Strongyloidiasis Presenting as Yellowish Nodules in Colonoscopy of an Immunocompetent Patient

Strongyloides stercoralis is endemic to tropical and subtropical regions, and infections are usually asymptomatic. However, immunocompromised patients, such as those receiving immunosuppressive therapy, high-dose steroids, or chemotherapy, can develop fatal hyperinfections. An 84-year-old man without any symptoms was diagnosed with strongyloidiasis during a regular screening colonoscopy. His medical history only involved a gastric endoscopic submucosal dissection for early gastric cancer 6 months previously. Few cases have been published about asymptomatic strongyloidiasis diagnosed in an immunocompetent host via endoscopic mucosal resection with characteristic colonoscopic findings. We report a case of colon-involved asymptomatic strongyloidiasis with specific colonic findings of yellowish-white nodules. This finding may be an important marker of S. stercoralis infection, which could prevent hyperinfections.

A case report of Strongyloides stercoralis infection in Leshan City / 中国血吸虫病防治杂志

This paper reports one case of gastric antral ulcer due to Strongyloides stercoralis infection in Leshan Traditional Chinese Medicine Hospital.

Seroepidemiological aspects of human infection by Strongyloides stercoralis in Alfenas, southern Minas Gerais, Brazil

Abstract INTRODUCTION: In most Strongyloides stercoralis infected individuals, nematoidosis occurs asymptomatically, but in immunocompromised patients, it can cause hyperinfection. Serological techniques seem to be a good alternative for detecting this parasite. METHODS The frequency of seropositivity for strongyloidiasis in Alfenas, MG, was estimated using the enzyme linked immunosorbent assay on blood samples, between May and August of 2015. RESULTS: Out of 258 samples tested, 53.9% were positive, and the frequency of seropositive individuals was higher in the peripheral districts of the municipality. CONCLUSIONS: The results indicate high seropositivity rates for strongyloidiasis among the residents of Alfenas city.

Características clínicas y epidemiológicas de la estrongiloidiasis en un hospital del Norte del Perú / Clinical and epidemiological characteristics of strongyloidiasis in a hospital in Northern Peru

Introducción: La infección por Strongyloides stercoralis constituye una de las enfermedades tropicales desatendidas en áreas endémicas como Perú, con una frecuencia global de 6,6%. Se puede diferenciar cuatro síndromes clínicos: agudo (SA), crónico (SC), hiperinfección (SH) y estrongiloidiasis diseminada (ED). Objetivo: Describir las características clínicas y epidemiológicas de los pacientes con diagnóstico de estrongiloidiasis. Material y métodos: Se estudió en forma retrospectiva 27 casos de pacientes con estrongioloidiasis atendidos en los meses de julio del 2014 a agosto del 2015 en el Hospital Regional Lambayeque, Perú. Resultados: Los pacientes tuvieron una mediana de edad de 41 años (rango intercuartílico: 2 a 84) y 74% (20/27) fueron varones. Se encontraron 10 casos (37,04%) de SC y 10 casos (37,04%) de SH. Del total, 63% presentaron eosinofilia, 85,2% anemia y 85,1% diarrea; 59,3% tuvo algún tipo de inmunocompromiso y 18,5% fallecieron. Conclusiones: La mayoría de pacientes con estrongiloidiasis de este estudio presentaron SC y SH, eosinofilia, anemia y algún tipo de inmunocompromiso. Asímismo, la alta frecuencia de estrongiloidiasis severa en pacientes con inmunocompromiso revela la necesidad de un tamizaje coproparasitológico con métodos específicos (Baerman y cultivo en agar) con el fin de detectar y tratar a tiempo la infección crónica previa.

Background: Strongyloides stercoralis infection is a neglected tropical disease in endemic areas such as Peru, with an overall frequency of 6.6%. Four clinical syndromes can be distinguished: acute (AS), chronic (CS), hyperinfection (HS) and disseminated strongyloidiasis (DS). Objective: To describe the clinical and epidemiological characteristics of patients diagnosed with strongyloidiasis. Material and methods: 27 clinical charts of patients with estrongioloidiasis admitted from July 2014 to August 2015 at the Hospital Regional Lambayeque, from Peru, were reviewed. Results: The median age was 41 years (Interquartile range: 2 to 84) and 74% (20/27) were males. There were 10 (37.04%) cases of CS and 10 cases (37.04%) of HS. Of the total, 63% presented eosinophilia, 85.2% anemia and 85.1% diarrhea; 59.3% were some type of immunocompromise and 18.5% died. Conclusions: The majority of patients with strongyloidiasis in this study presented CS and HS, eosinophilia, anemia, diarrhea and some type of immunocompromise. Also, the high frequency of severe strongyloidiasis in patients with immunocompromise reveals the need for a coproparasitological screening with specific methods (Baerman and agar culture) to detect and treat previously chronic infection.

Púrpura por Strongyloides stercoralis en un paciente inmunocompetente / Purpura due to Strongyloides stercoralis in an immunocompetent patient

Resumen La infección por Strongyloides stercoralis es una parasitosis frecuente en las regiones tropicales y subtropicales, incluyendo la Amazonía peruana. En pacientes con inmunocompromiso, las manifestaciones clínicas son variadas y es frecuente la diseminación sistémica de la enfermedad, con compromiso de diversos órganos. Las manifestaciones cutáneas son infrecuentes y se describen en pacientes con algún grado de inmunosupresión. Se presenta el caso de un paciente inmunocompetente que desarrolló una púrpura reactiva por una infección por Strongyloides stercoralis crónica. Ante ello, es posible el compromiso cutáneo en pacientes inmunocompetentes con reagudización sistémica por este parásito.

Infection with Strongyloides stercoralis is a common parasitic infection in tropical and subtropical regions, including the Peruvian Amazon. The clinical manifestations are varied in patients with immunocompromised disease, and the systemic spread of the disease is frequent, compromising different organs and systems. Cutaneous manifestations are infrequent, being described in patients with some degree of immunosuppression. We present the case of an immunocompetent patient who developed a reactive purpura due to chronic Strongyloides stercoralis infection. Thus, skin involvement is possible in immunocompetent patients with systemic exacerbation due to this parasite.