Humans seropositive for Trypanosoma cruzi co-infected with intestinal helminths have higher infectiousness, parasitaemia and Th2-type response in the Argentine Chaco.

BACKGROUND: The Gran Chaco ecoregion is a well-known hotspot of several neglected tropical diseases (NTDs) including Chagas disease, soil-transmitted helminthiasis and multiparasitic infections. Interspecific interactions between parasite species can modify host susceptibility, pathogenesis and transmissibility through immunomodulation. Our objective was to test the association between human co-infection with intestinal parasites and host parasitaemia, infectiousness to the vector and immunological profiles in Trypanosoma cruzi-seropositive individuals residing in an endemic region of the Argentine Chaco. METHODS: We conducted a cross-sectional serological survey for T. cruzi infection along with an intestinal parasite survey in two adjacent rural villages. Each participant was tested for T. cruzi and Strongyloides stercoralis infection by serodiagnosis, and by coprological tests for intestinal parasite detection. Trypanosoma cruzi bloodstream parasite load was determined by quantitative PCR (qPCR), host infectiousness by artificial xenodiagnosis and serum human cytokine levels by flow cytometry. RESULTS: The seroprevalence for T. cruzi was 16.1% and for S. stercoralis 11.5% (n = 87). We found 25.3% of patients with Enterobius vermicularis. The most frequent protozoan parasites were Blastocystis spp. (39.1%), Giardia lamblia (6.9%) and Cryptosporidium spp. (3.4%). Multiparasitism occurred in 36.8% of the examined patients. Co-infection ranged from 6.9% to 8.1% for T. cruzi-seropositive humans simultaneously infected with at least one protozoan or helminth species, respectively. The relative odds of being positive by qPCR or xenodiagnosis (i.e. infectious) of 28 T. cruzi-seropositive patients was eight times higher in people co-infected with at least one helminth species than in patients with no such co-infection. Trypanosoma cruzi parasite load and host infectiousness were positively associated with helminth co-infection in a multiple regression analysis. Interferon-gamma (IFN-γ) response, measured in relation to interleukin (IL)-4 among humans infected with T. cruzi only, was 1.5-fold higher than for T. cruzi-seropositive patients co-infected with helminths. The median concentration of IL-4 was significantly higher in T. cruzi-seropositive patients with a positive qPCR test than in qPCR-negative patients. CONCLUSIONS: Our results show a high level of multiparasitism and suggest that co-infection with intestinal helminths increased T. cruzi parasitaemia and upregulated the Th2-type response in the study patients.

Case Report: Duodenal Papillary Stenosis Secondary to Strongyloides stercoralis Infection in a Non-Immunocompromised Host.

Strongyloides stercoralis infection is a common infection in tropical and subtropical regions and is considered one of the "neglected tropical diseases." Owing to its life cycle, this infection can remain undetectable for years, preventing an early diagnosis and prompt treatment. We report the case of a 65-year-old woman who presented to us with a history of nausea, abdominal pain, bloating, and weight loss and, after initial radiologic and laboratory workup, was diagnosed with a periampullary mass with no secondary spread. She underwent an uneventful pylorus-preserving pancreatoduodenectomy, and on histopathological study of the lesion, a diagnosis of S. stercoralis infection was confirmed. This case stands out because of the importance of keeping S. stercoralis infections as a differential diagnosis of periampullary masses, particularly when the patient comes from regions where S. stercoralis is prevalent.

[Strongyloides stercoralis as uncommon cause of ascitic fluid infection in cirrhosis]. / Strongyloides stercoralis como causa infrecuente de infección de líquido ascítico en cirrosis.

Male patient, with a history of alcoholic cirrhosis frequent user of anti-inflammatory drugs including corticosteroids. He consulted for digestive bleeding secondary to a bulbar ulcer. During the admission, he had fever and antibiotic treatment with ceftriaxone is started, for a urinary infection. Fever persisted for 48 hours, so a diagnostic paracentesis was made: Strongyloides stercoralis larvae were seen in the direct microscopic exam. The patient started antiparasitic treatment with ivermectin. He was discharged and did not returned for follow up. Although infection with S. stercoralis is relatively common in patients with alcoholic liver cirrhosis, ascites infected with Strongyloides corresponds to an infrequent form of presentation. This case shows the importance of diagnostic paracentesis in every cirrhotic patient. It is important to consider atypical presentation of Strongyloides infection in the immunocompromised host, considering it could be fatal without treatment.

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 stercoralis como causa infrecuente de infección de líquido ascítico en cirrosis / Strongyloides stercoralis as uncommon cause of ascitic fluid infection in cirrhosis

Resumen Se comunica el caso clínico de un varón, con antecedentes de una cirrosis hepática alcohólica y gota, usuario crónico de antiinflamatorios, incluyendo corticoesteroides. Consultó por una melena secundaria a una úlcera bulbar. Durante su internación presentó fiebre, tratándose con ceftriaxona por un probable foco urinario. Por persistir febril, se realizó una paracentesis diagnóstica. En la muestra de líquido ascítico se observaron larvas de Strongyloides stercoralis. Recibió tratamiento antiparasitario con ivermectina, con buena respuesta clínica. Aunque la infección por S. stercoralis es relativamente frecuente en pacientes con cirrosis hepática alcohólica, la ascitis infectada por Strongyloides corresponde a una forma de presentación infrecuente. Este caso muestra la importancia de la paracentesis diagnóstica en todo paciente con ascitis secundaria a una cirrosis. Es importante considerar la presentación atípica de la infestación por Strongyloides en el contexto del paciente inmunocomprometido, ya que sin tratamiento puede tener una alta mortalidad.

Abstract Male patient, with a history of alcoholic cirrhosis frequent user of anti-inflammatory drugs including corticosteroids. He consulted for digestive bleeding secondary to a bulbar ulcer. During the admission, he had fever and antibiotic treatment with ceftriaxone is started, for a urinary infection. Fever persisted for 48 hours, so a diagnostic paracentesis was made: Strongyloides stercoralis larvae were seen in the direct microscopic exam. The patient started antiparasitic treatment with ivermectin. He was discharged and did not returned for follow up. Although infection with S. stercoralis is relatively common in patients with alcoholic liver cirrhosis, ascites infected with Strongyloides corresponds to an infrequent form of presentation. This case shows the importance of diagnostic paracentesis in every cirrhotic patient. It is important to consider atypical presentation of Strongyloides infection in the immunocompromised host, considering it could be fatal without treatment.

Immunosuppression as a trigger for hyperinflammatory syndrome due to Strongyloides stercolaris in membranous nephropathy. / Inmunosupresión como desencadenante de un síndrome de hiperinfestación por Strongyloides stercolaris en la nefropatía membranosa.

The relationship between parasites and glomerulonephritis (GN) is well documented in certain parasitoses, but not in cases of Strongyloides stercolaris (S. stercolaris) where there are few cases described being the majority GN of minimal changes. We report a case of hyperinfestation by S. stercolaris in a patient affected by a membranous GN treated with oral corticosteroids with fatal outcome for the patient. This case provides a double teaching: first about a rare association of strongyloid and membranous GN and second about the importance of establishing a diagnosis of suspected and appropriate treatment for certain infections or diseases with little clinical expression before starting any immunosuppressive treatment.

Utility of PCR in Patients with Strongyloides stercoralis and HTLV-1 Coinfection in French Guiana.

Strongyloides stercoralis and human T-lymphotropic virus 1 (HTLV-1) coinfections have been extensively reported in the literature, but the diagnosis and treatment of strongyloidiasis remains a challenge, particularly in HTLV-1 carriers. Our objectives were to evaluate the efficacy of a new PCR method for the detection of S. stercoralis in HTLV-1-positive patients. Stools were collected over a 1-year period across the endemic region of French Guiana, including remote forest areas. Two systems of real-time PCR were then used comparatively, with small subunit and specific repeat as respective targets, and compared with the results of microscopic examinations. One-hundred and twelve stool samples were included. Twenty-seven patients (24.1%) presented a positive HTLV-1 serology. The overall prevalence of strongyloidiasis among the 112 patients was 30% with small-subunit PCR and 11.6% with microscopic examinations. In the seropositive population, all tested stools were negative, whereas 51.2% were positive using small-subunit PCR. Thus, PCR allowed a much-improved sensitivity, particularly in HTLV-1 carriers. Among the two systems investigated, small subunit yielded better results than specific repeat PCR, with prevalence rates in HTLV-1 carriers of 51.2% and 22.2%, respectively. Therefore, PCR should be considered as a useful tool for the diagnosis of strongyloidiasis, particularly in HTLV-1 carriers who often present a light parasitic load due to erratic administration of anthelmintic drugs.

Regulatory T cells and IgE expression in duodenal mucosa of Strongyloides stercoralis and human T lymphotropic virus type 1 co-infected patients.

BACKGROUND: Strongyloides stercoralis is an intestinal nematode unique in its ability to replicate in the human host, allowing ongoing cycles of autoinfection, persisting for decades within the same host. Although usually asymptomatic, overwhelming infections can occur in Strongyloides and HTLV-1 co-infected individuals (SS/HTLV-1). Regulatory T cells (Tregs) are able to blunt specific Th2 responses necessary to control the parasite. We previously reported that peripheral blood Tregs are increased in SS/HTLV-1 and correlate with low Th2 responses. We hypothesized that Tregs are also increased at the site of infection in duodenal mucosa. METHODS: Paraffin embedded duodenal biopsies were obtained from 10 SS/HTLV-1 patients, 3 controls with non-parasitic chronic duodenitis, and 2 healthy controls. Immunohistochemistry was performed using monoclonal antibodies against human CD3, CD8, IgE and FoxP3. The number of cells were counted using a conventional light microscope. The number of CD3+, CD8+, FoxP3+ and IgE positive cells per 0.35 mm2 was measured using ImagePro Plus software comparing areas adjacent or distant from parasite material. RESULTS: In patients with SS/HTLV-1, T lymphocyte counts and CD8+ cells were lower in areas adjacent to the parasite compared to non-adjacent areas (CD3+: adjacent: 6.5 [Interquartile range (IQR: 2.8-12.3)]; non-adjacent: 24.5 [IQR: 20.9-34.4]; Mann-Whitney p = 0.0003; CD8+: adjacent: 4.5 [IQR: 2.3-11.8]; non-adjacent: 21 [IQR: 15.3-42.9]; Mann-Whitney p = 0.0011). Tregs cells in the intestines (FoxP3+ expressing cells) were increased in patients with SS/HTLV-1 compared with patients with chronic duodenitis (SS/HTLV-1: 1.5 [IQR: 0.7-2.3]; duodenitis controls: 0 [range 0-0.7]; healthy controls: 0; Mann-Whitney p = 0.034). There was also a trend towards fewer eosinophils adjacent to the parasites. Among SS/HTLV-1 patients the number of IgE expressing cells was increased for in areas not adjacent to the parasite compared to non-adjacent areas (ANOVA, p = 0.001). CONCLUSIONS: Our data shows increased Treg cell numbers localized adjacent to the parasites in the duodenum SS/HTLV-1 patients. In addition, other T lymphocytes and IgE expressing cells were decreased adjacent to the parasites, suggesting an important role for Tregs in down-regulating local parasite effector responses.

[Duodenal obstruction by Strongyloides stercoralis, an unusual complication]. / Obstrucción duodenal por Strongyloides stercoralis, una complicación inusual.

Strongyloidiasis is a neglected disease in Latin America. Gastrointestinal manifestations are nonspecific and duodenal obstruction is a rare complication. Here we present the case of a 31-year-old male from the central jungle of Peru, admitted due to a high intestinal obstruction, with duodenal ulcers and stenosis evidenced in the upper endoscopy. The histopathological report revealed presence of larvae of Strongyloides stercoralis. Clinical and endoscopic follow up were favorable with ivermectin treatment. There are near 20 reported cases of duodenal obstruction due to S. stercoralis. Additionally, infection by HTLV-1 was confirmed, being this a frequent association.

Imported strongyloidiasis: Data from 1245 cases registered in the +REDIVI Spanish Collaborative Network (2009-2017).

BACKGROUND: Imported strongyloidiasis is increasingly being diagnosed in non-endemic areas. The aim of this study was to describe the epidemiological, clinical and microbiological characteristics of patients with imported strongyloidiasis in Spain. METHODOLOGY: This is an observational retrospective study that included all patients diagnosed of strongyloidiasis registered in the +REDIVI Collaborative Network from 2009 to 2017. Demographic, epidemiological and clinical information was collected from the +REDIVI database, and extra information regarding microbiological techniques, treatment and follow-up was requested to participant centers. FINDINGS: Overall, 1245 cases were included. Most of them were immigrants (66.9%), and South America was the most frequent area of origin. Detection of larvae in stool samples was observed in 21.9% of the patients, and serological tests allowed making the diagnosis in the rest of the cases. Eosinophilia was present in 82.2% of cases. Treatment with ivermectin (compared with albendazole) was the most strongly associated factor to achieve the cure (OR 2.34). CONCLUSIONS: Given the long latency of the infection and the risk of developing a severe presentation, screening of S. stercoralis infection should be mandatory in patients coming from or had traveling to endemic areas, especially in those with immunosuppressant conditions.

Obstrucción duodenal por Strongyloides stercoralis, una complicación inusual / Duodenal obstruction by Strongyloides stercoralis, an unusual complication

Resumen La estrongiloidiasis es una enfermedad desatendida en Latinoamérica. Las manifestaciones gastrointestinales son inespecíficas y la obstrucción duodenal es una complicación infrecuente. Presentamos el caso clínico de un varón de 31 años, procedente de la selva central de Perú, que ingresó por una obstrucción intestinal alta, con úlceras y una estenosis duodenal evidenciadas en la endoscopia digestiva alta. El informe histopatológico reveló la presencia de larvas de Strongyloides stercoralis. La evolución clínica y endoscópica fueron favorables con el tratamiento con ivermectina. Existen poco más de 20 casos publicados de obstrucción duodenal por S. stercoralis. Adicionalmente, se confirmó una infección por HTLV-1, asociación descrita frecuente.

Strongyloidiasis is a neglected disease in Latin America. Gastrointestinal manifestations are nonspecific and duodenal obstruction is a rare complication. Here we present the case of a 31-year-old male from the central jungle of Peru, admitted due to a high intestinal obstruction, with duodenal ulcers and stenosis evidenced in the upper endoscopy. The histopathological report revealed presence of larvae of Strongyloides stercoralis. Clinical and endoscopic follow up were favorable with ivermectin treatment. There are near 20 reported cases of duodenal obstruction due to S. stercoralis. Additionally, infection by HTLV-1 was confirmed, being this a frequent association.

Influence of parasite load on the diagnosis and occurrence of eosinophilia in alcoholic patients infected with Strongyloides stercoralis.

Alcoholic patients are more susceptible to Strongyloides stercoralis infection. The chronic use of alcohol raises the levels of endogenous corticosteroids, which regulates the development of larvae and stimulates the differentiation of rhabditiform into infective filariform larvae, thus inducing internal autoinfection. Therefore, early diagnosis is important to prevent severe strongyloidiasis. The aim of this study was to evaluate the efficacy of parasitological methods, according to the parasite load and the number of stool samples, for diagnosis of S. stercoralis infection, as well the peripheral blood eosinophil count in alcoholic patients. A total of 330 patients were included in this study. The diagnosis was established using three parasitological methods: agar plate culture, Baermann-Moraes method and spontaneous sedimentation. Peripheral eosinophilia was considered when the level was >600 eosinophils/mm3. The agar plate culture (APC) had the highest sensitivity (97.3%). However, the analysis of multiple samples increased the sensitivity of all parasitological methods. The sensitivities of the methods were influenced by the parasite load. When the larval number was above 10, the sensitivity of APC was 100%, while in spontaneous sedimentation the sensitivity reached 100% when the larval number was above 50. In the present study, 15.4% of alcoholic patients infected with S. stercoralis (12/78) had increased peripheral blood eosinophil count (above 600 eosinophils/mm3). For an efficient parasitological diagnosis of S. stercoralis infection in alcoholic patients, repeated examination by two parasitological methods must be recommended, including agar plate culture due to its higher sensitivity. Moreover, S. stercoralis infection was associated with eosinophilia, mostly in patients excreting up to 10 larvae/g faeces.

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

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.

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.