Infection by Strongyloides venezuelensis attenuates chronic colitis induced by Dextran Sodium Sulfate ingestion in BALB/c mice.

Inflammatory bowel diseases (IBD) are chronic health problems of difficult management and treatment. Epidemiological studies indicate an inverse association between helminth infections and IBD, and experimental data confirm that helminth infections modulate the severity of experimental acute colitis in mice. However, the effects of helminth infections on chronic colitis, which is clinically more relevant, have been poorly explored. Herein, we investigated whether Strongyloides venezuelensis infection in BALB/c mice can ameliorate chronic colitis induced by the ingestion of water containing 2.5% Dextran Sodium Sulfate (DSS) over three seven-day treatment cycles, with an interval of fourteen days between cycles. Infected-only, DSS-exposed-only, and non-exposed/uninfected experimental groups served as controls for comparing the severity of colitis and intestinal inflammation among different groups. Our data showed that S. venezuelensis infection in mice with DSS-induced chronic colitis reduced clinical signs, attenuated colon shortening and inflammation, and prevented mucus ablation. The modulatory effect was accompanied by a low concentration of IFN-γ, high concentrations of TGF-ß, IL-22, and IL-33 in the colon, and a significant increase of the percentage of CD4+CD25+Foxp3+ Treg cells in the mesenteric lymph node (MLN). In conclusion, S. venezuelensis infection can reduce the severity of DSS-induced chronic colitis in mice possibly through the stimulation of Treg cells and modulatory cytokines, and induction of mucosal repair mechanisms.

Strongyloidiasis duodenum: A histopathological study.

Strongyloides stercoralis is an intestinal nematode that infects humans, percutaneously and has a complex life cycle. We report a case of a thirty year old male presenting with chief complaints of profuse watery diarrhoea, abdominal fullness, loss of appetite, creepy abdominal pain and low-grade fever for the last one month. He was on corticosteroids for systemic sclerosis. Endoscopy showed thickened and oedematous duodenal folds with pinpoint areas of bleeding and multiple ulcerations on the duodenal mucosa. Histopathologial examination of duodenal biopsy revealed infestation by Strongyloides stercoralis in the duodenum, the duodenal mucosal glands were occupied by various parts of parasite. The patient was successfully treated and had uneventful recovery.

Strongyloides-specific IgA, IgG and IgG immune complex profile in patients with pulmonary tuberculosis.

AIMS: To describe an anti-Strongyloides IgA, IgG and IgG immune complex antibody response profile in patients with pulmonary tuberculosis. METHODS AND RESULTS: Saliva and serum samples were collected from 100 individuals: group I, 50 apparently healthy individuals; and group II, 50 pulmonary tuberculosis patients. The IgA, IgG and IgG immune complex detection were carried out via an ELISA immunoenzymatic test. Optical density medians in saliva samples of IgA antibody (median of 7.21) and IgG-IC (median of 4.95) were significantly higher in tuberculosis group compared to control individuals (median IgA of 3.93 and IgG-IC of 2.38). CONCLUSION: This study presents antibody data to the field of pulmonary tuberculosis and strongyloidiasis coinfection, including saliva samples, and especially IgG immune complex detection.

Duodenal strongyloidiasis - Our 15-year histopathological experience at a tertiary gastrointestinal centre.

In order to emphasise the importance of histopathology in the clinically unsuspected diagnosis of duodenal strongyloidiasis, we report six cases diagnosed on duodenal biopsies identified from the database over a period of 15 years, and clinical, endoscopic and histopathological findings were analysed retrospectively. Four were elderly males and the remainder young females. Only one patient had an underlying immunocompromised state. Three presented with cholestatic jaundice and simulated hepatobiliary malignancy. In all cases, endoscopy provided non-specific findings. Only one case showed a predominant eosinophilic infiltrate. Eggs, larvae and adult forms of strongyloides were seen in crypts and showed intense basophilic staining on HE stain. It is concluded that since mostly undetected clinically, duodenal biopsy serves as the first step in the diagnosis of strongyloidiasis. Hepatobiliary manifestations, though very infrequent, should raise the suspicion for strongyloidiasis and thus necessitate the need for duodenal biopsy.

Helminth infection modulates systemic pro-inflammatory cytokines and chemokines implicated in type 2 diabetes mellitus pathogenesis.

BACKGROUND: The prevalence of helminth infections exhibits an inverse association with the prevalence of Type 2 diabetes mellitus (T2DM), and helminths are postulated to mediate a protective effect against T2DM. However, the biological mechanism behind this effect is not known. AIMS/METHODS: We postulated that helminth infections act by modulating the pro-inflammatory cytokine and chemokine milieu that is characteristic of T2DM. To examine the association of cytokines and chemokines in helminth-diabetes co-morbidity, we measured the plasma levels of a panel of pro-inflammatory cytokines and chemokines in individuals with Strongyloides stercoralis infection (Ss+) and T2DM at the time of Ss diagnosis and then 6 months after definitive anthelmintic treatment along with uninfected control individuals with T2DM alone (Ss-). PRINCIPAL FINDINGS: Ss+ individuals exhibited significantly diminished levels of the pro-inflammatory cytokines-IL-1α, IL-1ß, IL-6, IL-12, IL-18, IL-23, IL-27, G-CSF and GM-CSF and chemokines-CCL1, CCL2, CCL3, CCL11, CXCL1, CXCL2, CXCL8, CXCL9, CXCL10 and CXCL11. In contrast, Ss+ individuals exhibited significantly elevated levels of IL-1Ra. Anthelmintic treatment resulted in increased levels of all of the cytokines and chemokines. CONCLUSIONS: Thus, helminth infections alleviate and anthelmintic therapy partially restores the plasma cytokine and chemokine levels in helminth-diabetes co-morbidity. Our data therefore offer a plausible biological mechanism for the protective effect of helminth infections against T2DM.

Severe Strongyloides stercoralis infection in kidney transplant recipients: A multicenter case-control study.

BACKGROUND: Severe Strongyloides stercoralis infection in kidney transplant recipients is associated with considerable morbidity and mortality, although little is known about the risk factors for such infection. METHODOLOGY/PRINCIPAL FINDINGS: This was a retrospective, multicenter, case-control study in which we assessed the risk factors for and clinical outcomes of severe S. stercoralis infections in kidney transplant recipients in Brazil. We included 138 kidney transplant recipients: 46 cases and 92 controls. Among the cases, the median number of days from transplantation to diagnosis was 117 (interquartile range [IQR], 73.5-965) and the most common clinical findings were gastrointestinal symptoms (in 78.3%) and respiratory symptoms (in 39.1%), whereas fever and eosinophilia were seen in only 32.6% and 43.5%, respectively. The 30-day all-cause mortality among the cases was 28.3% overall and was significantly higher among the cases of infection occurring within the first three months after transplantation (47% vs. 17.2%, P = 0.04). The independent risk factors were receiving a transplant from a deceased donor (odds ratio [OR] = 6.16, 95% confidence interval [CI] = 2.05-18.5), a history of bacterial infection (OR = 3.04, 95% CI = 1.2-7.5), and a cumulative corticosteroid dose (OR = 1.005, 95% CI = 1.001-1.009). The independent predictors of mortality were respiratory failure (OR = 98.33, 95% CI = 4.46-2169.77) and concomitant bacteremia (OR = 413.00, 95% CI = 4.83-35316.61). CONCLUSIONS/SIGNIFICANCE: Severe S. stercoralis infections are associated with considerable morbidity and mortality after kidney transplantation. In endemic areas, such infection may occur late after transplantation, although it seems to be more severe when it occurs earlier after transplantation. Specific risk factors and clinical manifestations can identify patients at risk, who should receive prophylaxis or early treatment.

Helminth Coinfection Alters Monocyte Activation, Polarization, and Function in Latent Mycobacterium tuberculosis Infection.

Helminth infections are known to influence T and B cell responses in latent tuberculosis infection (LTBI). Whether helminth infections also modulate monocyte responses in helminth-LTBI coinfection has not been fully explored. To this end, we examined the activation, polarization, and function of human monocytes isolated from individuals with LTBI with (n = 25) or without (n = 25) coincident Strongyloides stercoralis infection (S. stercoralis-positive and S. stercoralis-negative respectively). Our data reveal that the presence of S. stercoralis infection is associated with lower frequencies of monocytes expressing CD54, CD80, CD86 at baseline (absence of stimulation) and in response to mycobacterial-Ag stimulation than monocytes from S. stercoralis-negative individuals. In contrast, S. stercoralis infection was associated with higher frequencies of M2-like monocytes, as determined by expression of CD206 and CD163. Monocytes from S. stercoralis-positive individuals had a reduced capacity to phagocytose or exhibit respiratory burst activity following mycobacterial-Ag or LPS stimulation and were less capable of expression of IL-1ß, TNF-α, IL-6, and IL-12 at baseline and/or following Ag stimulation compared with those without S. stercoralis infection. In addition, definitive treatment of S. stercoralis infection resulted in a significant reversal of the altered monocyte function 6 mo after anthelmintic therapy. Finally, T cells from S. stercoralis-positive individuals exhibited significantly lower activation at baseline or following mycobacterial-Ag stimulation. Therefore, our data highlight the induction of dampened monocyte activation, enhanced M2 polarization, and impaired monocyte function in helminth-LTBI coinfection. Our data also reveal a different mechanism by which helminth infection modulates immune function in LTBI.

Central Nervous System Strongyloides Stercoralis. A Case Report.

Strongyloidiasis is an infestation caused by the intestinal nematode Strongyloides stercoralis. It is potentially fatal in immunocompromised hosts due to its capacity to cause an overwhelming hyperinfestation however infested healthy individuals are usually asymptomatic. Hyperinfestation is extremely rare in the Central Nervous System (CNS) and usually limited to the gastrointestinal tract or lungs. CNS involvement in strongyloidiasis has only been seen in patients with hyperinfestation syndrome and may be fatal when misdiagnosed. In this report, we describe an unusual case of a 13-year-old girl presented with epileptic fits, multiple brain lesions and diagnosed as Strongyloides stercoralis infestation. Suitable frontal lesion biopsied and diagnosed as Strongyloides infestation and vasculitis. MRI features were totally regressed after the treatment with oral Albendazole for 3 months.

Strongyloides stercoralis infection in San Marino Republic: first epidemiological data from an observational study.

Strongyloides stercoralis is a neglected parasite that can cause death in immunocompromised individuals. There were no data on the epidemiology of S. stercoralis infection in San Marino Republic until two patients (one of whom died) were diagnosed with severe strongyloidiasis (hyperinfection) between September 2016 and March 2017. A serology test for Strongyloides spp. was introduced in routine practice in the laboratory of the State Hospital to test patients considered to be at risk for strongyloidiasis. Between August 2017 and August 2018, of 42 patients tested with serology, two (4.8%) were positive. An additional case was found by gastric biopsy. Two of the positive cases were presumably autochthonous infections (elderly people with no significant travel history), while the other was a probable imported case (young man born in Nigeria and settled in Europe since 2003). Epidemiology of strongyloidiasis in San Marino might be similar to Northern Italy, where a relevant proportion of cases was diagnosed in immigrants (mainly from sub-Saharan Africa) and in elderly Italians with eosinophilia. Screening for strongyloidiasis might be worthwhile in inhabitants of San Marino in the same categories of individuals, particularly those at risk of immune suppression.

Microfilaria and Strongyloides larva diagnosed in cerebrospinal fluid and ascitic fluid, respectively: Approach to their morphology on cytology.

Filariasis and Strongyloidiasis are two endemic parasitic infections seen in any tropical country. Filariasis, commonly caused by Wuchereria bancrofti, Brugia malayi, and Brugia timori is seen often in peripheral blood and lymphoid tissue. But it can be isolated from wide variety of soft tissue sites in the body like soft tissue lumps, breast, thyroid, body fluids. Strongyloides stercoralis, a helminthic infection, usually affects the respiratory and gastrointestinal (GI) tract, and frequently picked up in GI biopsies. However, in cases of hyper infection and patients with altered immunity, it can be isolated from other rare sites like body fluid samples. Accurate morphological Identification and confirmation are important for specific management. We report a case of microfilaria isolated from cerebrospinal fluid and a case of Strongyloides larva isolated from ascitic fluid in clinically unsuspected cases of these two parasitic infestations. We have also added a brief discussion on morphological differences between the two larval forms.

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.

Disseminated strongyloidiasis in an immunocompetent male: A Case Report.

Strongyloidiasis is a human parasitic disease caused by infection of Strongyloidesstercoralis. It can manifest from asymptomatic eosinophilia in an immunocompetent host and disseminate the disease in the immunocompromised ones. The inconsistency of eosinophilia and low sensitivity of a standard microscopic stool examination makes it difficult to diagnose the disease. We report a case of chronic strongyloidiasis who, despite being immunocompetent, developed dissemination. The patient was a 30-years-old male who presented with diarrhoea, vomiting, high-grade fever and dyspnoea. On examination, he was pale, oedematous and had ascites with systolic murmurs in tricuspid area. After a fullworkup for differentials, biopsy confirmed the diagnosis of strongyloidiasis. Echocardiogram revealed vegetations on mitral and tricuspid valves and regurgitation through the valves, which confirmed dissemination to endocardium. A course of Ivermectin 9 mg daily for two weeks eradicated the infection in time. In conclusion, awareness for physicians and the use of various diagnostic methods like serology, endoscopy and biopsy should be considered for high risk patients.

[Strongyloides hyperinfection in patient from Patagonia with HTLV-1 co-infection]. / Hiperinfección por Strongyloides en paciente de la Patagonia con co-infección por HTLV-1.

Strongylodiasis is an unattended condition caused by the parasite Strongyloides stercoralis. The Strongyloides hyperinfection syndrome can develop in immunosuppressed hosts, mainly in those with depression of cellular immunity. Co-infection with human T-cell lymphotropic virus (HTLV) is a risk factor for the development of severe forms of strongyloidiasis. We present the case of a 50-year-old man with Strongyloides hyperinfection and coinfection with HTLV. The diagnosis was delayed owing to its unusual epidemiology and an initial suspicion of inflammatory bowel disease. Identification of the parasite in bronchioalveolar lavage and duodenal and colonic mucosa biopsies confirmed the diagnosis. Subcutaneous ivermectin was used as an anthelmintic treatment with an adequate therapeutic response.

La estrongiloidiasis es una afección desatendida causada por el parásito Strongyloides stercoralis. En los individuos inmunosuprimidos, fundamentalmente en los que tienen depresión de la inmunidad celular, puede desarrollarse el síndrome de hiperinfección por Strongyloides. La coinfección con virus linfotrópico de células T humanas (HTLV) es un factor de riesgo para el desarrollo de formas graves de estrongiloidiasis. Presentamos el caso de un hombre de 50 años con hiperinfección por Strongyloides y coinfección con HTLV. Se demoró el diagnóstico debido a su epidemiología inusual y a la sospecha inicial de enfermedad inflamatoria intestinal. El diagnóstico se confirmó mediante la identificación del parásito en muestras de lavado bronquio-alveolar y biopsias de mucosa duodenal y colónica. Se utilizó ivermectina subcutánea como tratamiento antihelmíntico con adecuada respuesta terapéutica.

Hiperinfección por Strongyloides en paciente de la Patagonia con co-infección por HTLV-1 / Strongyloides hyperinfection in patient from Patagonia with HTLV-1 co-infection

La estrongiloidiasis es una afección desatendida causada por el parásito Strongyloides stercoralis. En los individuos inmunosuprimidos, fundamentalmente en los que tienen depresión de la inmunidad celular, puede desarrollarse el síndrome de hiperinfección por Strongyloides. La coinfección con virus linfotrópico de células T humanas (HTLV) es un factor de riesgo para el desarrollo de formas graves de estrongiloidiasis. Presentamos el caso de un hombre de 50 años con hiperinfección por Strongyloides y coinfección con HTLV. Se demoró el diagnóstico debido a su epidemiología inusual y a la sospecha inicial de enfermedad inflamatoria intestinal. El diagnóstico se confirmó mediante la identificación del parásito en muestras de lavado bronquio-alveolar y biopsias de mucosa duodenal y colónica. Se utilizó ivermectina subcutánea como tratamiento antihelmíntico con adecuada respuesta terapéutica.

Strongylodiasis is an unattended condition caused by the parasite Strongyloides stercoralis. The Strongyloides hyperinfection syndrome can develop in immunosuppressed hosts, mainly in those with depression of cellular immunity. Co-infection with human T-cell lymphotropic virus (HTLV) is a risk factor for the development of severe forms of strongyloidiasis. We present the case of a 50-year-old man with Strongyloides hyperinfection and coinfection with HTLV. The diagnosis was delayed owing to its unusual epidemiology and an initial suspicion of inflammatory bowel disease. Identification of the parasite in bronchioalveolar lavage and duodenal and colonic mucosa biopsies confirmed the diagnosis. Subcutaneous ivermectin was used as an anthelmintic treatment with an adequate therapeutic response.

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.