Navigating Clinical Utilization of Direct-from-Specimen Metagenomic Pathogen Detection: Clinical Applications, Limitations, and Testing Recommendations.

BACKGROUND: Metagenomic next generation sequencing (mNGS) is becoming increasingly available for pathogen detection directly from clinical specimens. These tests use target-independent, shotgun sequencing to detect potentially unlimited organisms. The promise of this methodology to aid infection diagnosis is demonstrated through early case reports and clinical studies. However, the optimal role of mNGS in clinical microbiology remains uncertain. CONTENT: We reviewed studies reporting clinical use of mNGS for pathogen detection from various specimen types, including cerebrospinal fluid, plasma, lower respiratory specimens, and others. Published clinical study data were critically evaluated and summarized to identify promising clinical indications for mNGS-based testing, to assess the clinical impact of mNGS for each indication, and to recognize test limitations. Based on these clinical studies, early testing recommendations are made to guide clinical utilization of mNGS for pathogen detection. Finally, current barriers to routine clinical laboratory implementation of mNGS tests are highlighted. SUMMARY: The promise of direct-from-specimen mNGS to enable challenging infection diagnoses has been demonstrated through early clinical studies of patients with meningitis or encephalitis, invasive fungal infections, community acquired pneumonia, and other clinical indications. However, the proportion of patient cases with positive clinical impact due to mNGS testing is low in published studies and the cost of testing is high, emphasizing the importance of improving our understanding of 'when to test' and for which patients mNGS testing is appropriate.

Detecting Schistosoma mansoni infections among pre-school-aged children in southern Ghana: a diagnostic comparison of urine-CCA, real-time PCR and Kato-Katz assays.

BACKGROUND: In Ghana, pre-school-aged children (PSAC) are at risk of intestinal schistosomiasis and are living in need of praziquantel treatment. To better assess the infection burden within this vulnerable demographic group, we have provided a comparative assessment of the prevalence of Schistosoma mansoni in pre-school-aged children by urine circulating cathodic antigen (CCA) dipsticks, real-time PCR Taqman® faecal assays and Kato-Katz coproscopy. METHODS: In all, 190 pre-school-aged children were sampled from three endemic communities (viz. Tomefa, Torgahkope/Adakope, and Manheam) around Weija dam, Southern Ghana. Fresh stool and urine samples were collected from all participants for diagnosis. RESULTS: Among all the three communities, the urine-CCA assay recorded the highest prevalence values of 90.5% (95% CI 80.4-96.4), 87.9% (95% CI 76.7-95), and 81.2% (95% CI 69.9-89.6) in Tomefa, Torgahkope/Adakope, and Manheam respectively. Prevalence by real-time PCR was 50% (95% CI 35.5-64.5), 8% (95% CI 2.2-19.2) and 16.7% (95% CI 8.3-28.5), while by Kato-Katz was 55.6% (95% CI 42.5-68.1), 8.6% (95% CI 2.9-19) and 11.6% (95% CI 5.1-21.6) respectively. Children aged 1 year and over were found to be positive with the urine-CCA assay; by the ages of 3-4, over 50% were urine-CCA patent. The sensitivity and specificity of the POC-CCA dipsticks, when compared against the combined results of Kato-Katz/TaqMan results was found to be 84.1% (95% CI = 72.7-92.1) and 12.9% (95% CI = 6.6-22) respectively. CONCLUSIONS: We propose that the urine-CCA dipstick may be a useful rapid diagnostic tool to estimate the prevalence of intestinal schistosomiasis in PSAC, particularly in rapid identification of at-risk areas. However, our assessment has shown that it possible to record false positives when compared to combined Kato-Katz and qPCR results. To guide PSAC praziquantel treatment needs, we propose the urine CCA assay should be included in routine surveillance of intestinal schistosomiasis alongside other diagnostics such as Kato-Katz and urine filtration.

Turning poop into profit: Cost-effectiveness and soil transmitted helminth infection risk associated with human excreta reuse in Vietnam.

Human excreta is a low cost source of nutrients vital to plant growth, but also a source of pathogens transmissible to people and animals. We investigated the cost-savings and infection risk of soil transmitted helminths (STHs) in four scenarios where farmers used either inorganic fertilizer or fresh/composted human excreta supplemented by inorganic fertilizer to meet the nutrient requirements of rice paddies in the Red River Delta, Vietnam. Our study included two main components: 1) a risk estimate of STH infection for farmers who handle fresh excreta, determined by systematic review and meta-analysis; and 2) a cost estimate of fertilizing rice paddies, determined by nutrient assessment of excreta, a retailer survey of inorganic fertilizer costs, and a literature review to identify region-specific inputs. Our findings suggest that farmers who reuse fresh excreta are 1.24 (95% CI: 1.13-1.37, p-value<0.001) times more likely to be infected with any STH than those who do not handle excreta or who compost appropriately, and that risk varies by STH type (Ascaris lumbricoides RR = 1.17, 95% CI = 0.87-1.58, p-value = 0.29; Hookworm RR = 1.02, 95% CI = 0.50-2.06, p-value = 0.96; Trichuris trichiura RR = 1.38, 95% CI = 0.79-2.42, p-value = 0.26). Average cost-savings were highest for farmers using fresh excreta (847,000 VND) followed by those who composted for 6 months as recommended by the WHO (312,000 VND) and those who composted for a shorter time (5 months) with lime supplementation (37,000 VND/yr); however, this study did not assess healthcare costs of treating acute or chronic STH infections in the target group. Our study provides evidence that farmers in the Red River Delta are able to use a renewable and locally available resource to their economic advantage, while minimizing the risk of STH infection.

Leishmania infantum is present in vaginal secretions of naturally infected bitches at lower levels in oestrogenized bitches than in non-oestrogenized bitches.

Naturally Leishmania infantum infected bitches were divided into oestrogenized (n = 11) and non-oestrogenized (n = 6) groups. Vaginal secretions were collected for polymerase chain reaction (PCR), and vulval, vaginal and uterine tissues were collected for the immunohistochemical (IHQ) identification of L. infantum. Parasite DNA was identified in vaginal secretions of non-oestrogenized (41.8%) and oestrogenized (18.2%) bitches (P<0.05; Fisher's Exact test). IHQ was positive in vulvar dermis (23.5%) and vaginal mucosa (17.7%) but negative in endometrium of all bitches. Poor association between positive vaginal secretion PCR and tissue IHQ (Kappa index) were observed. The results showed that genital secretions are a potential source for dog contamination.

Malignant Pleural Effusion with Filariasis.

The occurrence of microfilaria in pleural fluid is rare. Filarial lung involvement occurs in the form of Tropical Pulmonary Eosinophilia with pulmonary infiltrates and peripheral eosinophilia. We report a 74-year-old male patient, non smoker who was admitted to our hospital with breathlessness and chest discomfort of two weeks duration. He had, eosinophilia and deranged renal function. X-ray chest revealed massive left sided pleural effusion. Pleural fluid analysis revealed atypical cells and pleural fluid cytology showed microfilaria (Wuchereria bancrofti), which were also found on peripheral smear.

Diagnostic value of semi-purified antigens of hydatid cyst fluid in human cystic echinococcosis.

Cystic Echinococcosis (CE) is an infection caused by the larval stage of Echinococcus granulosus. The diagnosis of this disease has been problematic. Serological tests detecting antibodies against E. granulosus are the most popular and mainly use the crude Hydatid Cyst Fluid (HCF) or its components, Ag 5 and B. However, the diagnostic value of these tests is limited by the problems of specificity and/or sensitivity. The use of purified HCF antigens could be more helpful in the serodiagnosis of CE compared to the whole HCF. In the present study, we have evaluated the diagnostic value of semi-purified antigens using ELISA tests. Our results have shown that the 53 KDa antigen gave the best specificity (97.5%) and sensitivity (80%). We have also used Western Blot technique to analyze the serological profile against HCF. The results have confirmed that the most immunogenic component of HCF is the Ag 5.

[Evaluation of the new ImmunoCard STAT!® CGE test for the diagnosis of Amebiasis]. / Évaluation d'un nouveau test ImmunoCard STAT!® CGE pour le diagnostic de l'amibiase.

For many years, microscopic examination of stool samples has been considered to be the "gold standard" for diagnosis of intestinal parasites although the Polymerase Chain Reaction (PCR) analysis is increasingly utilized due to its high accuracy. Recently, PCR has been approved by the World Health Organization as the current method of choice for the diagnosis of Entamoeba histolytica infection. In this study we evaluated a novel immunochromatographic antigen detection rapid test, ImmunoCardSTAT CGE (Meridian Bioscence, Milan, Italy), which has been proposed for the diagnosis of infections caused by Cryptosporidium parvum-Giardia intestinalis-Entamoeba histolytica. There is another rapid test with a similar name, the ImmunoCard STAT! Crypto/Giardia, but it is just for Cryptosporidium and Giardia. We aimed to compare E. histolytica results obtained from the rapid test with those of a rt-PCR for the detection of E. histolytica / E. dispar DNA. The new ImmunoCard rapid antigen detection test exhibited 88% sensitivity and 92% specificity (if assessed on rt-PCR negative samples) but showed a high proportion of cross-reaction between the pathogenic E. histolytica and the non pathogenic E. dispar.

Detection of Toxoplasma gondii DNA in horse meat from supermarkets in France and performance evaluation of two serological tests.

In France, some cases of severe toxoplasmosis have been linked to the consumption of horse meat that had been imported from the American continent where atypical strains of Toxoplasma gondii are more common than in Europe. Many seroprevalence studies are presented in the literature but risk assessment of T. gondii infection after horse meat consumption is not possible in the absence of validated serological tests and the unknown correlation between detection of antibodies against T. gondii and presence of tissue cysts. We performed magnetic-capture polymerase chain reaction (MC-PCR) to detect T. gondii DNA in 231 horse meat samples purchased in supermarkets in France and evaluated the performance and level of agreement of the modified agglutination test (MAT) and enzyme-linked immunosorbent assay (ELISA) in the meat juices. The serological tests lacked sensitivity, specificity, and agreement between them, and there was no correlation with the presence of T. gondii DNA in horse meat, raising concerns about the reliability of T. gondii seroprevalence data in horses from the literature. T. gondii DNA was detected in 43% of horse meat samples but the absence of strain isolation in mice following inoculation of more than 100 horse meat samples suggests a low distribution of cysts in skeletal muscles and a low risk of T. gondii infection associated with horse meat consumption. However, to avoid any risk of toxoplasmosis, thorough cooking of horse meat is recommended.

Extracellular Onchocerca-derived small RNAs in host nodules and blood.

BACKGROUND: microRNAs (miRNAs), a class of short, non-coding RNA can be found in a highly stable, cell-free form in mammalian body fluids. Specific miRNAs are secreted by parasitic nematodes in exosomes and have been detected in the serum of murine and dog hosts infected with the filarial nematodes Litomosoides sigmodontis and Dirofilaria immitis, respectively. Here we identify extracellular, parasite-derived small RNAs associated with Onchocerca species infecting cattle and humans. METHODS: Small RNA libraries were prepared from total RNA extracted from the nodule fluid of cattle infected with Onchocerca ochengi as well as serum and plasma from humans infected with Onchocerca volvulus in Cameroon and Ghana. Parasite-derived miRNAs were identified based on the criteria that sequences unambiguously map to hairpin structures in Onchocerca genomes, do not align to the human genome and are not present in European control serum. RESULTS: A total of 62 mature miRNAs from 52 distinct pre-miRNA candidates were identified in nodule fluid from cattle infected with O. ochengi of which 59 are identical in the genome of the human parasite O. volvulus. Six of the extracellular miRNAs were also identified in sequencing analyses of serum and plasma from humans infected with O. volvulus. Based on sequencing analysis the abundance levels of the parasite miRNAs in serum or plasma range from 5 to 127 reads/per million total host miRNA reads identified, comparable to our previous analyses of Schistosoma mansoni and L. sigmodontis miRNAs in serum. All six of the O. volvulus miRNAs identified have orthologs in other filarial nematodes and four were identified in the serum of mice infected with L. sigmodontis. CONCLUSIONS: We have identified parasite-derived miRNAs associated with onchocerciasis in cattle and humans. Our results confirm the conserved nature of RNA secretion by diverse nematodes. Additional species-specific small RNAs from O. volvulus may be present in serum based on the novel miRNA sequences identified in the nodule fluid. In our analyses comparison to European control serum illuminates the scope for false-positives, warranting caution in criteria that should be applied to identification of biomarkers of infection.

Biological roles of cysteine proteinases in the pathogenesis of Trichomonas vaginalis.

Human trichomonosis, infection with Trichomonas vaginalis, is the most common non-viral sexually transmitted disease in the world. The host-parasite interaction and pathophysiological processes of trichomonosis remain incompletely understood. This review focuses on the advancements reached in the area of the pathogenesis of T. vaginalis, especially in the role of the cysteine proteinases. It highlights various approaches made in this field and lists a group of trichomonad cysteine proteinases involved in diverse processes such as invasion of the mucous layer, cytoadherence, cytotoxicity, cytoskeleton disruption of red blood cells, hemolysis, and evasion of the host immune response. A better understanding of the biological roles of cysteine proteinases in the pathogenesis of this parasite could be used in the identification of new chemotherapeutic targets. An additional advantage could be the development of a vaccine in order to reduce transmission of T. vaginalis.

Hydrocele fluid: can it be used for immunodiagnosis of lymphatic filariasis?

BACKGROUND & OBJECTIVES: Diagnosis of lymphatic filariasis using serum has been established but the utility of hydrocele fluid for the purpose is not exactly known. Since, hydrocele is a chronic form of the disease manifestation in a variety of situations and often poses difficulty in diagnosing its origin, we have evaluated the usefulness usage of hydrocele fluid for diagnosis of filarial origin of hydrocele in this study. METHODS: Paired samples of serum and hydrocele fluid from 51 individuals with hydrocele, living in an endemic area of Wuchereria bancrofti were assessed. Circulating filarial antigen, filarial specific antibody and cytokine assay were performed in both serum and hydrocele fluid of patients. RESULTS: Og4C3 assay detected circulating filarial antigen (CFA) in serum and corresponding hydrocele fluids. The level of IgG, IFN-γ and IL-10 were found to be high in CFA-negative, while IgM and IgE were high in CFApositive hydrocele fluid and serum samples associated with hydrocele. On the other hand neither CFA-positive nor CFA-negative hydrocele fluid and serum samples associated with hydrocele showed any difference in IgG4 level. INTERPRETATION & CONCLUSION: This study showed that the filaria related antigens and antibodies found in serum can be detected with equal sensitivity in hydrocele fluid. Therefore, it can be used as an alternative to serum for immunodiagnosis of filariasis, and help monitoring the filarisis elimination programme.

A protocol to improve genotyping of problematic microsatellite loci of Trypanosoma brucei gambiense from body fluids.

Microsatellite genotyping of Trypanosoma brucei gambiense, the causative agent of human African trypanosomiasis or sleeping sickness, and population genetics tools, are useful for inferring population parameters such as population size and dispersal. Amplifying parasite DNA directly from body fluids (i.e., blood, lymph or cerebrospinal fluid) allows avoiding costly and tedious isolation phases. It is however associated to increased frequencies of amplification failures (allelic dropouts and/or null alleles) at some loci. In this paper, we present a study focused on three T. brucei gambiense microsatellite loci suspected to present amplification problems when amplified from body fluids sampled in Guinean sleeping sickness foci. We checked for the real nature of blank and apparent homozygous genotypes of parasite DNA directly amplified from body fluids and tested the effect of three different DNA quantities of trypanosomes. Our results show that some initially blank and homozygous genotypes happen to be actual heterozygous genotypes. In Guinea, lymph from the cervical nymph nodes, known to contain the highest concentrations of parasites, appeared to provide the best amplification results. Simply repeating the PCR may be enough to retrieve the correct genotype, but we also show that increasing initial DNA content provides better results while undertaking first amplification. We finally propose an optimal protocol for amplifying trypanosome's DNA directly from body fluids that should be adapted to local characteristics and/or constraints.

Potential application of serological tests on fluids from carcasses: detection of antibodies against Toxoplasma gondii and Sarcoptes scabiei in red foxes (Vulpes vulpes).

BACKGROUND: Serological surveys for disease investigation of wild animal populations require obtaining blood samples for analysis, which has logistic, ethic and economic difficulties. Applying serological test to fluids collected from dead animals is an alternative. The aim of this study was to assess if antibodies could be detected in two types of fluids collected from 56 carcasses of red foxes (Vulpes vulpes): pleural fluid and lung extract. FINDINGS: In 22 (39%) foxes antibodies against Sarcoptes scabiei were detected in both fluid types by ELISA and Western blot. In 46 (82%) foxes, antibodies against Toxoplasma gondii were detected in pleural fluid and in 41 (73%) in lung extract applying a Toxo-screen test (DAT). Antibodies were still detectable in the same fluids kept at room temperature for 28 days, although in fewer foxes (16 and 14 foxes tested for T. gondii in lung extract and pleural fluid respectively; and 1 and 4 tested for S. scabiei in lung extract and pleural fluid respectively. CONCLUSIONS: These results indicate the potential utility of using fluids from carcasses for antibody screening of wild animals at the population level.

Modeling the distribution of ciliate protozoa in the reticulo-rumen using linear programming.

The flow of ciliate protozoa from the reticulo-rumen is significantly less than expected given the total density of rumen protozoa present. To maintain their numbers in the reticulo-rumen, protozoa can be selectively retained through association with feed particles and the rumen wall. Few mathematical models have been designed to model rumen protozoa in both the free-living and attached phases, and the data used in the models were acquired using classical techniques. It has therefore become necessary to provide an updated model that more accurately represents these microorganisms and incorporates the recent literature on distribution, sequestration, and generation times. This paper represents a novel approach to synthesizing experimental data on rumen microorganisms in a quantitative and structured manner. The development of a linear programming model of rumen protozoa in an approximate steady state will be described and applied to data from healthy ruminants consuming commonly fed diets. In the model, protozoa associated with the liquid phase and protozoa attached to particulate matter or sequestered against the rumen wall are distinguished. Growth, passage, death, and transfer of protozoa between both pools are represented. The results from the model application using the contrasting diets of increased forage content versus increased starch content indicate that the majority of rumen protozoa, 63 to 90%, are found in the attached phase, either attached to feed particles or sequestered on the rumen wall. A slightly greater proportion of protozoa are found in the attached phase in animals fed a hay diet compared with a starch diet. This suggests that experimental protocols that only sample protozoa from the rumen fluid could be significantly underestimating the size of the protozoal population of the rumen. Further data are required on the distribution of ciliate protozoa in the rumen of healthy animals to improve model development, but the model described herein does indicate that the attached protozoal population is a significant component of the total rumen protozoal community.

Importancia del estudio del balance del contenido vaginal (BACOVA) en el control preventivo de las trabajadoras sexuales / Importance of studying the balance of vaginal content (BAVACO) in the preventive control of sex workers

El objetivo de este trabajo fue estudiar a un grupo de 229 trabajadoras sexuales de Comodoro Rivadavia (Chubut), atendidas en centros públicos de salud de dicha ciudad, mediante la aplicación del método conocido como balance del contenido vaginal (BACOVA). Este método comprende el estudio morfológico de la microbiota vaginal, como así también de la reacción infamatoria. Incluye el análisis del contenido vaginal en fresco y por tinciones de Gram y de Giemsa, de modo de integrar la exploración de todo el panorama biológico. El 35,37 % de estas mujeres presentó microbiota normal (MN); el 15,72 %, microbiota intermedia (MI); el 23,14 %, vaginosis bacteriana (VB) y el 10,48 %, vaginitis microbiana inespecífca (VMI). Los casos de vaginitis por levaduras y por Trichomonas vaginalis comprendieron el 8,30 % y 6,99 % de las mujeres, respectivamente. Se observó el desplazamiento de la MN hacia una MI, que se correspondió con el predominio de bacterias corineformes. Por otra parte, no se reconoció un marcado desequilibrio del contenido vaginal ante la colonización e infección por levaduras o por T. vaginalis: el 48 % de los casos de estas vaginitis convencionales no presentaron reacción infamatoria vaginal (RIV). El 24,89 % de los casos de MN presentaron una signifcativa RIV, y en más del 50 % de las mujeres se diagnosticaron disfunciones vaginales en ausencia de sintomatología. Estos resultados se podrían asociar a un incremento del riesgo gineco-obstétrico, lo que afecta la salud sexual y reproductiva de la población estudiada.

The aim of this work was to study the vaginal microenvironment in sex workers from Comodoro Rivadavia, Chubut. For that purpose, BAVACO procedures were applied. A total of 229 female sex workers attended public health centers. Vaginal secretions were analyzed by Gram and Giemsa stains. The following results were obtained: normal microbiota 35.37 %, intermediate microbiota 15.72 %, bacterial vaginosis 23.14 %, microbial nonspecifc vaginitis, Donders'"aerobic vaginitis" 10.48 %, yeast vulvovaginitis 8.30 %, and trichomoniasis 6.99 %. The intermediate microbiota was characterized by a decrease in the number of lactobacilli and the presence of diphtheroid bacilli cell types. The population studied shared increased values of vaginal dysfunctions. These results are considered risk factors for obstetric and gynecologic diseases.

Case of sparganosis: a diagnostic dilemma.

Sparganosis, also known as larval diphyllobothriasis, is a rare disease of humans as man is not a natural host in the life cycle of Spirometra spp. Diagnosis of the latter is difficult as it mimics other conditions that commonly cause subcutaneous or visceral fluid collection. Clinical diagnosis of this particular case was also erroneously labelled as tuberculosis but later labelled as a case of sparganosis. To the best of our knowledge, this is the first case from India where a sparganum-like parasite was isolated in drain fluid from the perinephric area.

Identification of Tritrichomonas foetus pseudocysts in fresh preputial secretion samples from bulls.

Tritrichomonas foetus is a serious veterinary pathogen that causes bovine trichomonosis, a sexually transmitted disease that eventually leads to abortion and infertility. T. foetus has a simple life cycle that consists of only a trophozoitic form. During unfavorable environmental conditions, the trophozoites, which are polar and flagellated, can adopt a spherical shape and internalize their flagella. These rounded organisms are known as pseudocysts. Although it is currently assumed that T. foetus pseudocyst formation is reversible and that it represents a response to stressful conditions, there are no reports showing the presence of this form in vivo. For this reason, the aim of this study was to verify whether T. foetus pseudocysts are encountered in naturally infected bulls. Towards this goal, fresh preputial samples obtained from seven mature bulls that were naturally infected with T. foetus were analyzed using complementary techniques, such as video microscopy, fluorescence microscopy, scanning and transmission electron microscopy. The analyses revealed that approximately 55% of the parasites were in pseudocyst form in each preputial sample, whereas approximately 25% of T. foetus displayed pear-shaped bodies. Previous research demonstrated that in vitro T. foetus pseudocysts are able to divide by a budding process. Here, this division mode was observed in approximately 20% of fresh T. foetus obtained from preputial bovine samples. Thus, this study shows that in infected bulls, pseudocysts are present and occur more frequently than the pear-shaped parasites.

[Importance of studying the balance of vaginal content (BAVACO) in the preventive control of sex workers]. / Importancia del estudio del balance del contenido vaginal (BACOVA) en el control preventivo de las trabajadoras sexuales.

The aim of this work was to study the vaginal microenvironment in sex workers from Comodoro Rivadavia, Chubut. For that purpose, BAVACO procedures were applied. A total of 229 female sex workers attended public health centers. Vaginal secretions were analyzed by Gram and Giemsa stains. The following results were obtained: normal microbiota 35.37 %, intermediate microbiota 15.72 %, bacterial vaginosis 23.14 %, microbial non-specific vaginitis, Donders'"aerobic vaginitis" 10.48 %, yeast vulvovaginitis 8.30 %, and trichomoniasis 6.99 %. The intermediate microbiota was characterized by a decrease in the number of lactobacilli and the presence of diphtheroid bacilli cell types. The population studied shared increased values of vaginal dysfunctions. These results are considered risk factors for obstetric and gynecologic diseases.

Diagnostic yield of double-balloon enteroscopy with intestinal juice analysis for intestinal strongyloidiasis.

Strongyloidiasis is relatively common in tropical and subtropical areas. Most patients with Strongyloides stercoralis hyperinfection are immunocompromised, most commonly from corticosteroids or human T-cell lymphoma virus type 1 (HTLV-1) infection. We encountered a patient with HTLV-1 infection accompanied by paralytic ileus, in whom strongyloidiasis in the duodenum and jejunum was disclosed by esophagogastroduodenoscopy (EGD) and double-balloon enteroscopy (DBE). Until the age of 7 years, he lived on Amami-Oshima Island, Japan, where both S. stercoralis and HTLV-1 are endemic. EGD and peroral DBE disclosed white villi, edematous mucosa, and the disappearance of folds in the duodenum and jejunum. Biopsy specimens from the white villi in the duodenum and jejunum revealed S. stercoralis larvae. In both duodenal and jejunal juice, the rhabditiform larvae moved around. Because the larvae invade the lymph vessels, resulting in lymphangiectasia in edematous enteritis, the appearance of white villi may reflect villous atrophy/destruction and mucosal edema. Although our patient revealed no eosinophilia and negative stool specimens for parasites or ova, EGD and DBE with multiple biopsies and intestinal juice analysis are valuable diagnostic tools for strongyloidiasis.