A case of Strongyloides stercoralis infection.

Strongyloidiasis has been recognized as one of the life-threatening parasitic infections in the immunocompromised patients. We report an intestinal infection case of Strongyloides stercoralis in a 61-year-old man. Rhabditiform larvae were detected in the stool examination and developed to filariform larvae having a notched tail through the Harada-Mori filter paper culture. The patient received five courses of albendazole therapy but not cured of strongyloidiasis.     

A case of fatal malabsorption syndrome caused by strongyloidiasis complicated with isosporiasis and human cytomegalovirus infection]

This 54-year-old Korean coal miner suffered from continuous watery diarrhea and weight loss after corticosteroid treatment (beta-methasone, 4 mg daily for 1 week) due to hip-bone fracture in January 1991. Except for the short therapy of steroid, no other histories were contributory. The malabsorption syndrome was aggravated while the case was treated under the impression of amebiasis or intestinal tuberculosis. AIDS antibody test by EIA was negative and quantitative analysis of serum immunoglobulins was in normal ranges. Nine months after the onset of symptoms, the case was diagnosed as malabsorption syndrome caused by complexed and aggravated infection by Strongyloides stercoralis, Isospora and cytomegalovirus in the small intestine, which were proved by stool examination and duodenal biopsy. His clinical course became worse even after high-dosed and prolonged albendazole treatment for strongyloidiasis with supportive fluid therapy. The patient was discharged in hopeless status in November, 1991 and died after one week at home.     

Efficacy of ivermectin in the treatment of children parasitized by Strongyloides stercoralis

In a small village of Amazonian Colombia, the efficacy of ivermectin (200 microg/kg/day) was determined in a two-day treatment of children with uncomplicated strongyloidiasis. Criteria for inclusion in the study were as follows: absence of acute disease, no pretreatment with antiparasitic drugs within the last month, absence of severe liver or neurological disorders, and at least 2 of 4 stool samples positive for Strongyloides stercoralis. The Baermann technique was used to detect larvae; it had the advantage of reducing the frequency of false negative results in the subsequent examinations. Of 60 potential subjects, 49 fulfilled the above criteria. The cure rate for the S. stercoralis infection was 94% (46/49), with slight and temporary side effects. The effects of ivermectin on other intestinal parasites were characterized as well. In conclusion, a 200 microg/kg/d ivermectin dose was an adequate therapeutic regimen in the treatment of uncomplicated strongyloidiasis in children.     

Molecular diagnosis of strongyloidiasis in tropical areas: a comparison of conventional and real-time polymerase chain reaction with parasitological methods

This study aimed to evaluate the use of conventional polymerase chain reaction (cPCR) and real-time quantitative PCR (qPCR) in the diagnosis of human strongyloidiasis from stool samples in tropical areas. Stool samples were collected from individuals and were determined to be positive for Strongyloides stercoralis (group I), negative for S. stercoralis (group II) and positive for other enteroparasite species (group III). DNA specific to S. stercoralis was found in 76.7% of group I samples by cPCR and in 90% of group I samples by qPCR. The results show that molecular methods can be used as alternative tools for detecting S. stercoralis in human stool samples in tropical areas.     

Reproduction of epigastric pain of duodenal ulceration by adenosine.

Intravenous boluses of adenosine produced transient epigastric discomfort indistinguishable from spontaneous pain in five of six patients with endoscopically confirmed duodenal ulcer, an effect which was slightly but significantly antagonised by aminophylline. These findings may be relevant to the pathophysiology of peptic ulcer pain.     

Twice-Daily Versus Thrice-Daily Clarithromycin in Combination with Ranitidine Bismuth Citrate in the Eradication of Helicobacter pylori

Background. Ranitidine bismuth citrate (RBC), 400 mg bid for 4 weeks, plus clarithromycin, 500 mg tid, is a regimen approved by the US Food and Drug Administration for the eradication of Helicobacter pylori in patients with duodenal ulcers. Proof that the clarithromycin portion of the regimen could be given twice daily without loss of efficacy would reduce cost and improve patient compliance. The objective of this study was to compare the H. pylori eradication rates in patients who had duodenal ulcer and were randomly assigned to 4 weeks of treatment with RBC, 400 mg bid, in conjunction with 2 weeks of therapy with either clarithromycin, 500 mg tid, or clarithromycin, 500 mg bid. Patients and Methods. Patients who had a duodenal ulcer and were H. pylori–positive by at least two tests were randomly assigned to (1) RBC, 400 mg bid for 4 weeks, plus clarithromycin, 500 mg tid for 2 weeks, or (2) RBC, 400 mg bid for 4 weeks, plus clarithromycin, 500 mg bid for 2 weeks. H. pylori eradication was assessed 4 weeks after completion of RBC plus clarithromycin. Results. Three hundred eighty-three patients from 78 centers had a duodenal ulcer and were H. pylori–positive. The modified intent-to-treat (MITT) and the per-protocol (PP) eradication rates were statistically equivalent between the twice-daily (65% MITT, 74% PP) and thrice-daily (63% MITT, 73% PP) clarithromycin treatment regimens. Incidence and types of adverse events did not differ between the two groups. Conclusions. For eradicating H. pylori in patients with duodenal ulcer, clarithromycin, 500 mg bid for 2 weeks, with RBC, 400 mg bid for 4 weeks, is equivalent to clarithromycin, 500 mg tid with RBC. The potential enhancement of patient compliance, reduced cost of clarithromycin, and equivalent efficacy would support the use of twice-daily clarithromycin in triple-therapy regimens with RBC.     

Comorbid Gastric Adenocarcinoma and Gastric and Duodenal Strongyloides stercoralis Infection: A Case Report

Strongyloides stercoralis can cause systemic infection, termed strongyloidiasis, and gastrointestinal ulcer disease in immunocompromised patients. However, to our knowledge, there are no reported cases of comorbid gastric adenocarcinoma and S. stercoralis infection. Here, we report a case of an 81-year-old Korean man who presented with S. stercoralis infection coexisting with early gastric adenocarcinoma (T1aN0M0). S. stercoralis eggs, rhabditiform larvae, and adult females were observed in normal gastric and duodenal crypts. They were also observed in atypical glands representative of adenocarcinoma and adenoma. Preliminary laboratory tests revealed mild neutrophilic and eosinophilic leukocytosis. A routine stool test failed to detect rhabditiform larvae in the patient’s fecal sample; however, S. stercoralis was identified by PCR amplification and 18S rRNA sequencing using genomic DNA extracted from formalin-fixed paraffin-embedded tissues. Postoperatively, the patient had a persistent fever and was treated with albendazole for 7 days, which alleviated the fever. The patient was followed-up by monitoring and laboratory testing for 4 months postoperatively, and no abnormalities were observed thus far. The fact that S. stercoralis infection may be fatal in immunocompromised patients should be kept in mind when assessing high-risk patients.     

A Case of Fatal Strongyloidiasis in a Patient with Chronic Lymphocytic Leukemia and Molecular Characterization of the Isolate

Strongyloides stercoralis is a human intestinal parasite which may lead to complicated strongyloidiasis in immunocompromised. Here, a case of complicated strongyloidiasis in a patient with chronic lymphocytic leukemia is reported. Presence of numerous S. stercoralis larvae in feces and sputum confirmed the diagnosis of hyperinfection syndrome in this patient. Following recovery of filariform larvae from agar plate culture of the stool, the isolate was characterized for the ITS1 region of ribosomal DNA gene by nested-PCR and sequencing. Albendazole therapy did not have cure effects; and just at the beginning of taking ivermectin, the patient died. The most important clue to prevent such fatal consequences is early diagnosis and proper treatment.     

Diagnosis of Strongyloides stercoralis in a peritoneal effusion from an HIV-seropositive man. A case report

BACKGROUND: Strongyloides stercoralis, a nematode parasite in humans with free-living and autoinfective cycles, is often an asymptomatic infection of the upper small intestine. If the host becomes immunocompromised, autoinfection may increase the intestinal worm burden and lead to disseminated strongyloidiasis. The parthenogenetic adult female larvae can remain embedded in the mucosa of the small intestine for years, producing eggs that develop into either rhabditiform, noninfective larvae or filariform, infective larvae. Manifestations of dissemination occur when the filariform larvae penetrate the intestinal wall and migrate into the blood. Pulmonary involvement is common, and the central nervous system may be affected. Blood eosinophilia is typical, and gram-negative sepsis from enteric bacteria may occur. Much less commonly described is invasion of the peritoneal cavity with peritoneal effusion. CASE: A 49-year-old man who came to the United States from Liberia 4 years earlier presented with sudden onset of severe abdominal distention, generalized weakness and marked pedal edema. Diagnostic paracentesis showed numerous filariform larvae of S stercoralis. Stool examination confirmed the presence of both rhabditiform and filariform larvae. Subsequently the patient was found to be HIV seropositive, with a CD4 lymphocyte count of 59. CONCLUSION: Early detection of S stercoralis may alter the often-fatal course of infection. The present case is the second reported one in the English-language literature of the diagnosis of S stercoralis in ascitic fluid.     

Strongyloidiasis in a Diabetic Patient Accompanied by Gastrointestinal Stromal Tumor: Cause of Eosinophilia Unresponsive to Steroid Therapy

We report here a case of strongyloidiasis in a 72-year-old diabetic patient (woman) accompanied by gastrointestinal stromal tumor receiving imatinib therapy, first diagnosed as hypereosinophilic syndrome and treated with steroids for uncontrolled eosinophilia. She suffered from lower back pain and intermittent abdominal discomfort with nausea and diagnosed with gastrointestinal stromal tumor. After post-operative imatinib treatment eosinophilia persisted, so that steroid therapy was started under an impression of hypereosinophilic syndrome. In spite of 6 months steroid therapy, eosinophilia persisted. Stool examination was performed to rule out intestinal helminth infections. Rhabditoid larvae of Strongyloides stercoralis were detected and the patient was diagnosed as strongyloidiasis. This diagnosis was confirmed again by PCR. The patient was treated with albendazole for 14 days and her abdominal pain and diarrhea improved. This case highlights the need for thorough investigation, including molecular approaches, to test for strongyloidiasis before and during steroid therapies.     

Strongyloides stercoralis: identification of a protease that facilitates penetration of skin by the infective larvae

Host invasion and tissue migration of several helminths have been linked to the expression and release of parasite-derived proteases. One of the most remarkable examples of tissue migration is that of larvae of the nematode parasite Strongyloides stercoralis, which can move through tissue at speeds of up to 10 cm per hour. We have shown the Strongyloides L3 larvae secrete a potent histolytic metalloprotease to facilitate their rapid migration. This protease has elastase activity and catalyzes the degradation of a model of dermal extracellular matrix. The importance of this enzyme in the pathogenesis of strongyloidiasis is underscored by the observation that invasion by larvae of skin in vitro is prevented by metalloprotease inhibitors. These results substantiate the role of proteases as virulence factors in strongyloidiasis, as well as other related parasitic infections, and suggest new approaches to therapy.     

An Alternative Non-Macrolide, Non-Imidazole Treatment Regimen for Curing Helicobacter pylori and Duodenal Ulcers: Ranitidine Bismuth Citrate Plus Amoxicillin

Background. Because patients who fail to be cured of H. pylori infection following macrolide or imidazole therapy are difficult to treat, there is a clear need for a reasonably effective and simple second-line treatment regimen. The purpose of these two studies was to evaluate the efficacy of ranitidine bismuth citrate (RBC) plus amoxicillin for the cure of H. pylori infection and for healing duodenal ulcers and preventing ulcer relapse.
Materials and Methods. Two identically designed randomized, double-blind, double-dummy studies were conducted in patients with an H. pylori -associated duodenal ulcer. Patients were treated with either RBC 400 mg bid for 4 weeks plus amoxicillin 500 mg qid for 2 weeks, RBC 400 mg bid for 4 weeks and placebo qid for 2 weeks, placebo bid for 4 weeks and amoxicillin 500 mg qid for 2 weeks, or placebo bid for 4 weeks and placebo qid for 2 weeks. Patients with healed ulcers after 4 weeks of treatment were eligible for entry into a 24-week observation phase for the assessment of H. pylori status (culture, histology, and CLOtest^TM) and ulcer relapse.
Results. A total of 229 patients with confirmed H. pylori infection at baseline were evaluated. Of these, 132 whose ulcers had healed entered the 24-week posttreatment observation phase. The combination of RBC plus amoxicillin resulted in higher H. pylori cure rates (55%) and higher duodenal ulcer healing (74%) than did either treatment alone. All treatments were well tolerated.
Conclusions. The combination of ranitidine bismuth citrate plus amoxicillin cures H. pylori infection in more than half of the patients treated. This treatment regimen shows promise as the basis for future non-macrolide, non-imidazole triple therapy regimens for curing H. pylori infection. Such regimens may be appropriate second-line treatment for patients who are resistant to or who are unable to tolerate macrolide- or imidazole-containing therapies.     

Use of larval, parasitic female and egg antigens from Strongyloides venezuelensis to detect parasite-specific IgG and immune complexes in immunodiagnosis of human strongyloidiasis

The aim of this study was to use larval, parasitic female and egg antigens from Strongyloides venezuelensis to detect parasite-specific IgG and immune complexes in human serum samples by enzyme-linked immunosorbent assay (ELISA). In total, 95 serum samples were analysed, consisting of 30 patients harbouring S. stercoralis larvae, 30 healthy subjects and 35 patients with other parasites. Sensitivity, specificity and diagnostic efficiency were calculated. A significant statistical difference was found in the detection of immune complexes and antibodies in patients harbouring S. stercoralis larvae from larval and eggs antigens, with higher positivity using larval antigen. The larval antigen showed the highest values for sensitivity, specificity and diagnostic efficiency in ELISA from detection of immune complexes. For the first time we used IgG anti-larvae, IgG anti-parasitic females or IgG anti-eggs for immune complex detection. We concluded that the association of antibody and immune complex detection could be used in the diagnosis of human strongyloidiasis.     

A human case of Echinostoma hortense (Trematoda: Echinostomatidae) infection diagnosed by gastroduodenal endoscopy in Korea

A human Echinostoma hortense infection was diagnosed by gastroduodenoscopy. An 81-year-old Korean male, living in Yeongcheon-shi, Gyeongsangbuk-do and with epigastric discomfort of several days duration, was subjected to upper gastrointestinal endoscopy. He was in the habit of eating fresh water fish. Two live worms were found in the duodenal bulb area and were removed using an endoscopic forceps. Based on their morphological characteristics, the worms were identified as E. hortense. The patient was treated with praziquantel 10 mg/kg as a single dose. The source of the infection in this case remains unclear, but the fresh water fish consumed, including the loach, may have been the source. This is the second case of E. hortense infection diagnosed by endoscopy in Korea.     

Strongyloidiasis associated with amebiasis and giardiaisis in an immunocompetent boy presented with acute abdomen

Strongyloides stercoralis (SS) is an intestinal nematode that is mainly endemic in tropical and subtropical regions and sporadic in temperate zones. SS infection frequently occurs in people who have hematologic malignancies, HIV infection and in individuals undergoing immunosuppressive therapy. In this study, we report a 12- year-old immunocompetent boy who was admitted to our hospital with acute abdomen. Laboratory evaluation showed strongyloidiasis, amebiasis and giardiasis. Clinical and laboratory findings immediately improved with albendazole therapy. Therefore, when diarrhea with signs of acute abdomen is observed, stool examinations should be done for enteroparasitosis. This approach will prevent misdiagnosis as acute abdomen. Complete clinical improvement is possible by medical therapy without surgical intervention.     

A new modified concomitant therapy for Helicobacter pylori eradication in Turkey

Background: Helicobacter pylori eradication rates have tended to decrease recently, mostly due to antibiotic resistance. In the present study, our aim was to determine Hp eradication rate with the LAC plus tid metronidazole regimen and the secondary objective of this study was to identify an effective regimen for our population. Methods: Eighty‐four Hp‐positive patients with non‐ulcer dyspepsia were assigned into the same group. Patients were administered the classical LAC protocole (lansoprazole 30 mg bid, amoxicillin 1 g bid and claritromycin 500 mg bid for 14 days) plus metronidazole 500 mg tid for 14 days. Gastroscopy and histopathological assessment were performed before enrollment and C¹⁴ urea breath test and stool antigen test were performed 6 weeks after treatment. Results: All 84 patients completed the study. No patient left the study because of drug side effect. Total eradication rate was 75% (63/84). Conclusion: Although LAC plus tid metronidazole regimen achieved a much better eradication rate compared with the standard LAC regimen; this is the first study that has a relatively low success with a concomitant therapy. So in areas of high resistance like Turkey, one cannot expect a high success with any clarithromycin containing regimen and those should be avoided.     

A case of fatal hyperinfective strongyloidiasis with discovery of autoinfective filariform larvae in sputum

The autoinfective filariform larva of Strongyloides stercoralis causes hyperinfection in immunosuppressed hosts. Here we report on the case of a male patient who was admitted to the emergency room at Gwangju Veterans Hospital with a complaint of dyspnea, and who was receiving corticosteroid therapy for asthma. Many slender larvae of S. stercoralis with a notched tail were detected in Papanicolaou stained sputum. They measured 269 +/- 21.2 microm in length and 11 +/- 0.6 microm in width. The esophagus extended nearly half of the body length. The larvae were identified putatively as autoinfective third-stage filariform larvae, and their presence was fatal. The autoinfective filariform larva of S. stercoralis has not been previously reported in Korea.     

Strongyloides stercoralis hyperinfection syndrome presenting as mechanical ileus after short-course oral steroids for chronic obstructive pulmonary disease (COPD) exacerbation

We report a case of a fatal Strongyloides stercoralis hyperinfection syndrome (SHS) in a migrant from Kenya, who had been living in Germany for three decades. A short-course oral steroid treatment for Chronic Obstructive Pulmonary Disease (COPD) exacerbation had been administered four weeks prior to the presentation. The initial clinical and radiological findings suggested a mechanical small bowel obstruction as a cause of ileus. Our case highlights the importance of maintaining a high index of suspicion for strongyloidiasis in patients from endemic areas even years after they left the country of origin. It demonstrates that even a five-day course of prednisolone is able to trigger SHS in patients with underlying strongyloidiasis. History of frequent previous administration of oral prednisolone for COPD exacerbations in our case raises the question why and how the last steroid regimen provoked SHS. SHS can present with multiple gastrointestinal symptoms including ileus and the absence of eosinophilia during the whole course of the disease should not lower the level of suspicion in the appropriate clinical setting.