Diagnosis Of Strongyloidiasis Research Articles

Concomitant Serological and Molecular Methods for Strongyloides stercoralis Screening in an Endemic Area of Spain.

Strongyloidiasis is a widespread parasitic disease that can be life-threatening in immunosuppressed people. In the Mediterranean basin, autochthonous cases coexist with imported ones. We aimed to assess the utility of different screening methods, along with the frequency of strongyloidiasis and its associated risk factors in migrants and the native population. This cross-sectional study took place from 2019 to 2022 in the area of the Vega Baja Hospital in Alicante, Spain. Screening was performed in people who were immunosuppressed, at risk of immunosuppression, with blood asymptomatic eosinophilia, and in asymptomatic people from highly endemic countries. Screening methods were serological techniques (ELISA), stool parasitological tests (fecal concentration methods and agar plate culture), and a stool molecular test (PCR). Of the 168 participants (62.5% males, 53.0% migrants, 36.3% immunosuppressed, median age 57 years), 14 (8.3%) had confirmed strongyloidiasis, where 6 were confirmed by serology, 4 by PCR, and 4 by both methods. Overall, 9% of the migrants and 7.6% of the native-born patients were infected. Elevated IgE and hemoglobin and Latin American origin were associated with strongyloidiasis diagnosis. Screening with serology alone would have missed 28.6% of cases. We conclude that strongyloidiasis prevalence is high in our population, both in native and migrant groups, and stool PCR is a useful tool to increase case detection.

Systematic Review of Strongyloides stercoralis Infection Diagnosis in Southeast Asia: Insights from Parasitological, Molecular, and Serological Approaches.

Accurate diagnosis of strongyloidiasis is crucial for effective treatment and prevention of complications. We reviewed the current landscape of diagnostic assays used in detecting Strongyloides infection in Southeast Asia. A literature search was performed using Scopus, PubMed, and Web of Science databases spanning the last three decades. Based on the exclusion and inclusion criteria, 52 papers were included in this review. We outlined the diagnostic methods used and their advantages and drawbacks. Insensitive parasitological methods were commonly used, thus underscoring the underestimation of Strongyloides infection rates in Southeast Asia. A combination of diagnostic methods (i.e., microscopy, molecular techniques, and serology) is preferred because it leads to more effective detection and higher prevalence rates. New approaches have been developed, including urine ELISAs and rapid lateral flow tests. Improving and standardizing diagnostics and making them more accessible can improve Strongyloides prevalence estimates and facilitate control efforts.

Design and expression of a chimeric recombinant antigen (SsIR-Ss1a) for the serodiagnosis of human strongyloidiasis: Evaluation of performance, sensitivity, and specificity.

The sensitivity of parasitological and molecular methods is unsatisfactory for the diagnosis of strongyloidiasis, and serological techniques are remaining as the most effective diagnostic approach. The present study aimed to design and produce a chimeric recombinant antigen from Strongyloides stercoralis immunoreactive antigen (SsIR) and Ss1a antigens, using immune-informatics approaches, and evaluated its diagnostic performance in an ELISA system for the diagnosis of human strongyloidiasis. The coding sequences for SsIR and Ss1a were selected from GenBank and were gene-optimized. Using bioinformatics analysis, the regions with the highest antigenicity that did not overlap with other parasite antigens were selected. The chimeric recombinant antigen SsIR- Ss1a, was constructed. The solubility and physicochemical properties of the designed construct were analyzed and its tertiary structures were built and evaluated. The construct was expressed into the pET-23a (+) expression vector and the optimized DNA sequences of SsIR-Ss1a (873 bp) were cloned into competent E. coli DH5α cells. Diagnostic performances of the produced recombinant antigen, along with a commercial kit were evaluated in an indirect ELISA system, using a panel of sera from strongyloidiasis patients and controls. The physicochemical and bioinformatics evaluations revealed that the designed chimeric construct is soluble, has a molecular with of 35 KDa, and is antigenic. Western blotting confirmed the immunoreactivity of the produced chimeric recombinant antigen with the sera of strongyloidiasis patients. The sensitivity and specificity of the indirect ELISA system, using the produced SsIR-Ss1a chimeric antigen, were found to be 93.94% (95% CI, 0.803 to 0.989) and 97.22% (95% CI, 0.921 to 0.992) respectively. The preliminary findings of this study suggest that the produced SsIR-Ss1a chimeric antigen shows promise in the diagnosis of human strongyloidiasis. However, these results are based on a limited panel of samples, and further research with a larger sample size is necessary to confirm its accuracy. The construct has potential as an antigen in the ELISA system for the serological diagnosis of this neglected parasitic infection, but additional validation is required.

Serological diagnosis of strongyloidiasis: An evaluation of three commercial assays.

Strongyloidiasis is caused by a neglected nematode, manifesting as chronic intestinal infection with potentially severe manifestations. The disease is an emerging problem in non-endemic countries affecting travelers and migrants. Diagnosis of strongyloidiasis is hampered by the lack of standardization and absence of a gold standard. Since adequate direct methods to detect the motile larvae in stool samples are not widely available, other techniques such as serology have been developed. We evaluated three commercial ELISA kits (DRG Instruments, IVD Research, and Bordier Affinity Products) to detect IgG antibodies against Strongyloides stercoralis assays utilizing serum samples from travelers with microscopically confirmed strongyloidiasis (n = 50) and other imported helminthic infections (n = 159) as well as healthy controls (n = 50). The DRG, IVD, and Bordier assays showed sensitivities of 58.0%, 64.0%, and 56.0%, respectively. Specificity values were 96.0%, 96.0%, and 92.0% in healthy controls, and 67.3%, 62.9%, and 76.7% in cases with other helminth infections, respectively. Cross-reactions were mostly observed in cases with other nematodes (37.5%, 42.5%, and 20.0%, respectively), but also in trematode (33.3%, 38.1%, and 19.0%, respectively) and in cestode infections (25.0%, 30.0%, and 32.5%, respectively). The study demonstrates the diagnostic limitations of serological assays to detect or exclude cases of strongyloidiasis in returning travelers, who frequently present with recent or acute infections.

Modifications to the parasitological technique of Rugai increase the diagnostic sensitivity for strongyloidiasis.

Strongyloidiasis is a neglected tropical disease caused mainly by Strongyloides stercoralis, a nematode that can persist for decades in the human host with a very low parasitic burden and without specific symptoms. Hence, it is difficult to diagnose and control. Larval concentration and culture methods with fecal samples show higher sensitivity for the diagnosis of Strongyloides-infected individuals; however, these techniques are not routinely used, primarily due to the challenges associated with processing a substantial volume of fecal samples. In the current study, we comparatively evaluated the sensitivity and applicability of modifications made to the Rugai parasitological method for the diagnosis of strongyloidiasis in fecal samples of experimentally infected rats and in 68 individuals from an urban community close to Maceió, Brazil. The presence and quantity of parasite larvae in the feces were comparatively evaluated using different parasitological techniques. In the experimental model, we demonstrated that the modified Rugai technique (RMOD) allowed for significantly higher recovery of larvae than the original Rugai technique (RO). Moreover, the sediment was cleaner and easier to evaluate using optical microscopy. Compared to other parasitological techniques, such as agar-plate culture (A-PC) and spontaneous sedimentation (SS), the RMOD technique showed higher sensitivity in the detection of larvae in all infected groups and presented comparatively better performance, especially in rats with a low parasite burden. In the human population, among the 68 stool samples evaluated, Strongyloides larvae were detected in the feces of six individuals with an estimated prevalence of 8.82%. However, the performance of each parasitological method was remarkably different. SS identified Strongyloides larvae in only two individuals and A-PC in three, whereas RMOD was able to identify six infected individuals, resulting in sensitivities of 33.3%, 50%, and 100%, respectively. In conclusion, the modifications introduced to the Rugai technique resulted in improved sensitivity for the detection of Strongyloides spp. infections, especially in stool samples with a low parasite burden, in comparison with other routinely used parasitological techniques.

First field study using Strong-LAMP for diagnosis of strongyloidiasis in Cubal, Angola

BackgroundStrongyloides stercoralis infection is a common neglected tropical disease distributed worldwide, mainly in tropical and subtropical climates. The impact of S. stercoralis infections on human health ranges from mild asymptomatic infections to chronic strongyloidiasis unnoticeable until the host is immunosuppressed. In severe strongyloidiasis, a syndrome of hyperinfection and larval dissemination to various organs can occur with high mortality rates. The diagnosis of strongyloidiasis is challenging because of the absence of a single standard reference test with high sensitivity and specificity, which also makes it difficult to estimate the accuracy of other diagnostic tests. This study aimed to evaluate, for the first time, the use of an easy-to-perform loop-mediated isothermal amplification (LAMP) colorimetric assay (named Strong-LAMP) for the molecular screening of strongyloidiasis in stool samples from patients in a low-resource endemic area in Cubal, Angola. To compare different LAMP application scenarios, the performance of the Strong-LAMP under field conditions in Angola was reassessed in a well-equipped reference laboratory in Spain and compared with a quantitative polymerase chain reaction (qPCR) method.MethodsA total of 192 stool samples were collected from adult population in Cubal, Angola, and examined by parasitological methods (direct saline microscopy and Baermann’s technique). DNA was extracted from each stool sample using a commercial kit and tested by the colorimetric Strong-LAMP assay for the detection of Strongyloides spp. under field conditions. Furthermore, all samples were shipped to a well-equipped laboratory in Spain, reanalysed by the same procedure and compared with a qPCR method. The overall results after testing were compared.ResultsStrongyloides stercoralis larvae were identified by direct saline microscopy and Baermann in a total of 10/192 (5.2%) and 18/192 (9.4%) stool samples, respectively. Other helminth and protozoan species were also identified. The Strong-LAMP-positive results were visually detected in 69/192 (35.9%) stool samples. The comparison of Strong-LAMP results in field conditions and at a reference laboratory matched in a total of 146/192 (76.0%) samples. A total of 24/192 (12.5%) stool samples tested positive by qPCR.ConclusionsThis is the first study in which colorimetric Strong-LAMP has been clinically evaluated in a resource-poor strongyloidiasis endemic area. Strong-LAMP has been shown to be more effective in screening for strongyloidiasis than parasitological methods under field conditions and qPCR in the laboratory. Our Strong-LAMP has proven to be a field-friendly and highly accurate molecular test for the diagnosis of strongyloidiasis.Graphical

Periumbilical purpuric rash as a clue to the diagnosis of strongyloidiasis and HTLV-1 infection

ABSTRACT Strongyloidiasis is a parasitic disease caused by the nematode Strongyloides stercoralis, widely distributed in Brazil. In general, it manifests with nonspecific gastrointestinal symptoms. However, in severe cases, pulmonary, neurological and systemic manifestations may occur, culminating in high mortality rates. Exceptionally, there may be a single-appearing periumbilical purpuric eruption. The prognosis is related to the rapid diagnosis and to beginning of the therapy. The case of an elderly man, former alcoholic, with chronic abdominal pain, fever and unexplained weight loss, in addition to periumbilical purpura is reported on this study. The manifestation motivated a specific investigation in which resulted in the diagnosis of strongyloidiasis and infection by human T-lymphotropic virus 1 (HTLV-1). KEY WORDS: Strongyloidiasis; Strongyloides stercoralis; HTLV-1; Purpura

S2348 Watch for Those Bumps! Yellow Nodules on Colonoscopy With Colonic Eosinophilia Leading to the Diagnosis of Strongyloidiasis

S2348 Watch for Those Bumps! Yellow Nodules on Colonoscopy With Colonic Eosinophilia Leading to the Diagnosis of Strongyloidiasis

Bacterial meningoencephalitis secondary to disseminated strongyloidiasis in a pacient with COVID-19

Introduction. Strongyloidiasis in a parasitic diseases determined by the intestinal nematode Strongyloides stercoralis. In most cases, this disease is asymptomatic, but the immunocompromised patients can develop severe forms like hyper infestation and disseminated strongyloidiasis. There severe forms of the disease are associated with bacteremias with gastrointestinal microorganisms which can determine infectious complication anywhere in the body. Bacterial meningitis is the most common complication of this kind. Case presentation. We present you the case of a 78 years old patient who initially presented in another hospital for suddenly installed aphasia. He was clinical and paraclinical evaluated and the suspected diagnosis was acute meningoencephalitis, so he was transferred in our hospital. This is a case about a patient with an immunocompromised status determined by recent infection with SARS-CoV-2 who was hospitalized and received prolonged corticosteroid therapy. The clinical examination performed at the admission shows a patient with mediocre general status, partially cooperative, partially time-spatial oriented and to one’s own person, discreet neck stiffness, anxious-depressive mood, with acute respiratory failure. A coproparasitological examination is performed which reveals the presence of filariform larvae of Strongyloides stercoralis in the stool. Also, a parasitic PCR test from a stool sample is positive for Strongyloides stercoralis. These clinical and paraclinical findings corroborated with those found in the cerebrospinal fluid examination establish the diagnosis: acute bacterial meningoencephalitis secondary to disseminated strongyloidiasis. During the disease’s evolution, he is confirmed with a new infection with SARS-CoV-2. He receives antiviral treatment, antiparasitic treatment, antibiotic treatment and symptomatic treatment. The evolution of the disease is favorable. Conclusions. The immunocompromised status of the patient determined the evolution of the infestation with Strongyloides stercoralis to a severe form complicated with acute bacterial meningoencephalitis. The difficulty in establishing the diagnosis of strongyloidiasis is represented by the fact that Romania is a non-endemic country for the infection with this parasite.

Incidental diagnosis of strongyloidiasis in a patient with hepatic metastasis

Strongyloides stercoralis is a soil-transmitted helminth infecting humans that can cause hyperinfection and disseminated disease in the immunocompromised host. This case report describes a 56-year-old patient, diagnosed with hepatic metastasis, who was screened for strongyloidiasis by faecal culture. The agar plate culture became positive on the third day of incubation, demonstrating characteristic tracks and yielding rhabditiform larvae. The charcoal and Harada-Mori cultures were negative. The patient was treated with albendazole for 7 days but declined further follow up.

Diagnostic performance of Strongyloides-specific IgG4 detection in urine for diagnosis of human strongyloidiasis

BackgroundDetection of parasite-specific IgG in urine is a sensitive method for diagnosis of strongyloidiasis and gives similar accuracy to serum IgG. However, there are no data concerning detection of IgG subclass in urine. To further explore the utility of diagnosis from urine samples, we evaluated the diagnostic performance of IgG4 in urine compared with parasitological and other immunological methods.MethodsThe urine and sera included proven strongyloidiasis (group 1, n = 93), other parasitic infections (group 2, n = 40) and parasite negatives (group 3, n = 93). The performance of Strongyloides-specific IgG4 in urine for diagnosis of strongyloidiasis using fecal examinations as the reference standard was assessed.ResultsWith fecal examination as a gold standard, Strongyloides-specific IgG4 in urine had 91.4% sensitivity and 93.2% specificity while serum IgG4 had 93.6% sensitivity and 91.0% specificity. IgG4 in both urine and serum had almost perfect diagnostic agreements with fecal examination (Cohen's kappa coefficient was > 0.8). Cross-reactivity to Opisthorchis viverrini and Taenia spp. of IgG4 in urine were 7.5% and 12.5% in serum. Concurrent analyses of total IgG in urine and serum showed that the sensitivities (97.9–100%) and specificities (88.7–91.0%) were similar (P > 0.05). The sensitivity for parasitological examination by the formalin-ethyl acetate concentration technique (FECT) was 49.5% and that for agar plate culture technique (APC) it was 92.6%.ConclusionOur findings showed that specific IgG4 detection in urine yielded similar diagnostic performance to the same biomarkers in serum. This suggests that accurate diagnosis of strongyloidiasis can be performed using urine samples and IgG4 is a valid choice of diagnostic marker. Further assessment is required to assess the utility of urine IgG4 for measuring the response treatment in strongyloidiasis.Graphical

Proliferative strongyloidiasis in a colony of colubrid snakes.

Strongyloides are small rhabditid nematodes primarily associated with enteric disease in a variety of animal species, including reptiles. Strongyloides spp life stages were associated with a disease outbreak in a large breeding colony of snakes. Multiple Pantherophis and Lampropeltis colubrids exhibited respiratory distress, anorexia, stomatitis, facial deformation, and waning body condition that resulted in death or necessitated euthanasia. Postmortem examinations of 13 snakes revealed epithelial hyperplasia and inflammation of the alimentary and respiratory tracts associated with varying numbers of adult and larval nematodes and embryonated or larvated ova. In a subset of snakes, aberrant nematode migration was also observed in the eye, genitourinary system, coelom, and vasculature. Histomorphology and gross examination of parasitic adult female nematodes from host tissues were consistent with a Strongyloides spp. Sedimented fecal material from 101/160 (63%) snakes housed in the affected facility was positive for nematodes and/or larvated ova. Polymerase chain reaction amplification and sequencing of portions of the 18S and 28S ribosomal ribonucleic acid (RNA) genes and the internal transcribed spacer region of adult female parasites and positive fecal samples supported the diagnosis of strongyloidiasis. Strongyloides spp possess a unique life cycle capable of alternating between parasitic (homogonic) and free-living (heterogonic) stages, resulting in the production of directly infective larvae. Commonly utilized husbandry practices in reptile collections can amplify the numbers of infective larvae generated in the captive environment, increasing the risk for rhabditid hyperinfections. This report documents morbidity, mortality, and non-enteric disease manifestations due to Strongyloides hyperinfections in a captive colubrid snake colony.

Epidemiology of strongyloidiasis determined by parasite-specific IgG detections by enzyme-linked immunosorbent assay on urine samples using Strongyloides stercoralis, S. ratti and recombinant protein (NIE) as antigens in Northeast Thailand.

Detection of anti-Strongyloides IgG in urine by enzyme-linked immunosorbent assay (ELISA) for diagnosis of strongyloidiasis reportedly has comparable performance to conventional serum assays. Initial comparisons of urine assays using commercial ELISA kits designated for serology have shown its diagnostic potential but sub-optimal accuracy. In the present study, we optimized urine ELISA protocols based on different antigen types and evaluated their accuracies in determining the epidemiology of strongyloidiasis in Northeast Thailand. Paired urine and fecal samples of 966 individuals from the study community were collected for three consecutive days and tested for strongyloidiasis. We compared three ELISA protocols using different antigens including crude S. stercoralis antigen (Ss-ELISA), crude S. ratti antigen (Sr-ELISA) and recombinant NIE antigen (NIE-ELISA) and fecal examination by agar plate-culture (APCT) technique and formalin-ethyl acetate concentration technique (FECT). The optimized ELISA protocols using three different antigen sources yielded significantly higher prevalence rates of strongyloidiasis (58.9-65.1%) than those by fecal examination methods (19.7%). The prevalence of strongyloidiasis determined by ELISA protocols significantly increased with age (p value < 0.0001) and males had higher prevalence than females (p value < 0.0001). Diagnostic agreements between ELISA protocols were moderate (κ = 0.461-0.586) and the agreement between each ELISA protocol and fecal examinations were slight (κ = 0.139-0.210). The results obtained by urine ELISA protocols using three different antigens showed comparable diagnostic performances, provided further supports for the utility of urine as an alternative clinical specimen for diagnosis of strongyloidiasis.

Upper Gastrointestinal Bleeding Induced by Gastric Ulcer Secondary to Strongyloidiasis: A Case Report.

gastric ulcer; gastrointestinal haemorrhage; Strongyloides stercoralis; strongyloidiasis.

Comparison of different PCR amplification targets for molecular diagnosis of Strongyloides stercoralis.

Molecular techniques are an alternative for the diagnosis of strongyloidiasis, produced by Strongyloides stercoralis. However, it is necessary to determine the best amplification target for the populations of this parasite present in a geographical area and standardize a polymerase chain reaction (PCR) protocol for its detection. The objectives of this work were the comparison of different PCR targets for molecular detection of S. stercoralis and the standardization of a PCR protocol for the selected target with the best diagnostic results. DNA extraction was performed from parasite larvae by saline precipitation. Three amplification targets of the genes encoding ribosomal RNA 18S (18S rDNA) and 5.8S (5.8S rDNA) and cytochrome oxidase 1 (COX1) of S. stercoralis were compared, and the PCR reaction conditions for the best target were standardized (concentration of reagents and template DNA, hybridization temperature, and number of cycles). The analytical sensitivity and specificity of the technique were determined. DNA extraction by saline precipitation made it possible to obtain DNA of high purity and integrity. The ideal target was the 5.8S rDNA, since the 18S rDNA yielded non-reproducible results and COX1 never amplified under any condition tested. The optimal conditions for the 5.8S rDNA-PCR were: 1.5 mM MgCl2, 100 μM dNTPs, 0.4 μM primers, and 0.75 U DNA polymerase, using 35 cycles and a hybridization temperature of 60 °C. The analytical sensitivity of the PCR was 1 attogram of DNA, and the specificity was 100%. Consequently, the 5.8S rDNA was shown to be highly sensitive and specific for the detection of S. stercoralis DNA.

Strongyloidiasis infection in a borderline lepromatous leprosy patient with adrenocorticoid insufficiency undergoing corticosteroid treatment: a case report

Strongyloidiasis is a soil-transmitted helminthiasis mainly caused by Strongyloides stercoralis. It is endemic to the tropics and subtropics. Sri Lanka has a 0-1.6% prevalence rate. S. stercoralis infection was identified in a 33-year-old Sri Lankan male patient treated with corticosteroids for borderline lepromatous leprosy with adrenocortical dysfunction. In March 2020, a 33-year-old Sri Lankan (Sinhalese) male patient presented with watery diarrhea, lower abdominal pain, and post-prandial abdominal fullness. Previously, he was diagnosed with borderline lepromatous leprosy and was treated with rifampicin, clofazimine, and prednisolone 60mg daily since July 2019. After developing gastrointestinal symptoms, he had defaulted leprosy treatment including the prednisolone for 3months. Duodenal biopsy revealed numerous intraepithelial nematodes within the lumina of glands in the duodenum whose appearance favored Strongyloides. Fecal wet smear revealed numerous Strongyloidisstercoralis L1 rhabditiform larvae. Larval tracks were seen in the agar plate culture. L3 filariform larvae of Strongyloidis stercoralis were seen in the Harada-Mori culture. In addition, the short synacthen test revealed adrenocortical insufficiency, and oral hydrocortisone and fludrocortisone were started with albendazole treatment against strongyloidiasis. Fecal wet smear and culture repeated after treatment with albendazole were negative for Strongyloidisstercoralis. The patient was discharged in July 2020 on oral hydrocortisone. Onemonth later his condition was reviewed and the repeated fecal wet smear and agar plate culture was normal. He is being followed up every 3months. This is the first case of strongyloidiasis diagnosed in a patient with borderline lepromatous leprosy from Sri Lanka. The patient manifested symptoms of strongyloidiasis while on high-dose steroid therapy for his lepromatous reaction. Subsequently, the patient not only discontinued his steroid therapy, but also developed adrenocortical insufficiency as a complication of leprosy. Therefore, although diagnosis of strongyloidiasis was delayed, his subsequent low steroid levels probably protected him from disseminated disease. This is an interesting case where symptomatic strongyloidiasis was diagnosed in a patient who was initially treated with high-dose steroids but subsequently developed adrenocortical insufficiency. We emphasize the need to screen all patients prior to the commencement of immunosuppressive therapy.

Strongyloides stercoralis: A Neglected but Fatal Parasite.

Strongyloidiasis is a disease caused by Strongyloides stercoralis and remains a neglected tropical infection despite significant public health concerns. Challenges in the management of strongyloidiasis arise from wide ranging clinical presentations, lack of practical high sensitivity diagnostic tests, and a fatal outcome in immunocompromised hosts. Migration, globalization, and increased administration of immunomodulators, particularly during the COVID-19 era, have amplified the global impact of strongyloidiasis. Here, we comprehensively review the diagnostic tests, clinical manifestations, and treatment of strongyloidiasis. The review additionally focuses on complicated strongyloidiasis in immunocompromised patients and critical screening strategies. Diagnosis of strongyloidiasis is challenging because of non-specific presentations and low parasite load. In contrast, treatment is simple: administration of single dosage ivermectin or moxidectin, a recent anthelmintic drug. Undiagnosed infections result in hyperinfection syndrome and disseminated disease when patients become immunocompromised. Thus, disease manifestation awareness among clinicians is crucial. Furthermore, active surveillance and advanced diagnostic tests are essential for fundamental management.

Immune complexes as a tool for strongyloidiasis immunodiagnosis in kidney and liver transplant candidate.

Strongyloidiasis is a chronic and asymptomatic infection in immunocompetent patients. Immunocompromised patients, such as organ transplant candidates, can develop severe forms of this disease, and the best way to prevent progression to these forms is early diagnosis. Serological techniques using specific IgG and immune complexes (IC) detection can help in the diagnosis of these patients. This study aimed to detect specific anti-Strongyloides IC and IgG antibodies in kidney transplant (KT) and liver transplant (LT) candidates. A total of 100 blood samples was collected from transplant candidates (50 blood samples each from KT and LT candidates). Serum was obtained and analysed using enzyme-linked immunosorbent assay for IC and IgG detections. The IC levels showed frequencies of 18% and 2% in the KT and LT groups, respectively, whereas anti-Strongyloides IgG was detected in 34% and 12% of KT and LT candidates, respectively. The correlation between IC and IgG detection is poor in KT candidates, while in LT candidates, there is a significant positive correlation. The detection of IC can be an additional tool for the diagnosis of strongyloidiasis, especially when associated with the detection of specific IgG anti-Strongyloides antibodies.

Comparison of different staining methods for the nematode Strongyloides papillosus isolated from rabbits

Strongyloidiasis in rabbits is a disease caused by Strongyloides papillosus helminths, manifested by skin inflammation, diarrhea, weight loss, and stunting of animals in growth and development. Confirmation of invasion is carried out mainly by required methods of helminthoovoscopy and helmintholarvoscopy. The most well-known methods of helmintholarvoscopic diagnosis of feces for strongyloidiasis are the method of D. Baermann (1917) and its modifications according to V. I. Shilnikov (1983), the method using the “asterisk” device (according to V. F. Nikitin and T. Pavlasek, 1988), the method of coprohelmintho-larvoscopic rings (according to S. I. Ponomar, N. M. Soroka, 2007), the method of T. I. Popova, standardized by S. I. Ponomar (2003). There are no laboratory methods with 100 % reliability at the present stage. Therefore, our studies on improving the lifelong helminthocoprological diagnosis of strongyloidiasis in rabbits are relevant. Our work aimed to compare different methods of staining the pathogen S. papillosus. Laboratory studies were carried out in the laboratories of the Department of Parasitology and Veterinary Sanitary Expertise of the Dnipro State Agrarian and Economic University. For staining S. papillosus, 20 dyes were used: 1 % alizarin red, 1 % brilliant blue, Turk's solution, 1 % brilliant green, 1 % methylene blue, 1 % amido black 10B, 1 % eosin, Ziehl's solution, Lugol's solution, 1 % сarbolic gentian violet, Romanowsky-type, 1 % Sudan, 1 % bromophenol blue, 1 % orange G, 1 % bromocresol green, 1 % safranin, Zadorozhny-Dozmorov's-type, Mikhin's-type, Muromtsev's-type. We have proposed 20 dyes for staining the internal organs of larvae and free-living males and females pathogens of Strongyloides without or with temperature fixation. Live pathogens S. papillosus, without temperature fixation, pass only Lugol's and safranin's solutions. All other dyes showed the highest staining, but only when the preparation was heated for 2–3 seconds to 60 °C. However, the dyes showed different degrees of coloration. Bromocresol green stained the walls of the internal organs of the helminth. Namely, the nematodes acquired a green color, and the membranes of a part of the esophagus and intestines became dark green. During microscopy, this allowed accurate identification and differentiation into larvae and free-living males and females of S. papillosus and simplified their counting.

A Rare Cause of Pedunculated Polyps Caused by Strongyloides

Introduction: Strongyloidiasis is a systemic disease caused by the nematode Strongyloides stercoralis. Strongyloides is unique among parasites in that it can remain undetected for decades. Although patients may present with the typical symptoms of a skin rash, cough or diarrhoea, a rare manifestation of infection is pseudopolyposis in the colon. This case highlights the unique finding of pseudopolyposis in a patient with strongyloidiasis with negative stool studies. Case description: We present the case of an 81-year-old man with a delayed diagnosis of strongyloidiasis. The patient initially presented to the clinic for evaluation of productive cough and was treated empirically for bronchitis. He subsequently developed vomiting and diarrhoea with imaging revealing circumferential wall thickening of the ascending colon, consistent with colitis. Although stool tests were negative, the patient was treated with antibiotics, and then underwent a colonoscopy which revealed multiple polyps. Biopsy results confirmed Strongyloides infection. The patient was treated with ivermectin and improved. Discussion: This case describes the unique finding of colonic pseudopolyposis in a patient infected with Strongyloides in rural southwest Virginia. Strongyloidiasis is often misdiagnosed due to its non-specific gastrointestinal symptoms and the chronic nature of the disease. Although stool studies are routinely negative for parasitic infection, CT scan findings suggestive of colitis should be followed by colonoscopy with biopsy of any abnormal lesion in the right clinical context. Determining the definitive diagnosis in a timely manner is crucial for establishing the specific treatment and for resolution of the disease.