Strongyloides hyperinfection and hypogammaglobulinemia

Improved diagnostic sensitivity of human strongyloidiasis using point-of-care mixed recombinant antigen-based immunochromatography

Strongyloidiasis is a neglected tropical disease that can cause fatal complications due to hyperinfection and disseminated strongyloidiasis in immunocompromised patients. We used two Strongyloides stercoralis recombinant antigenic proteins, L3NieAg.01 (NIE) and IgG-immunoreactive antigen (SsIR), to develop the recombinant antigen-based immunochromatography test (ICT) kit. We constructed and compared kits using either the NIE (NIE ICT kit) or the SsIR (SsIR ICT kit) antigens and a kit using a mixture of both (NIE-SsIR ICT kit) for detection of anti-Strongyloides IgG antibody in human serum samples. Serum samples from normal healthy individuals (Group I, n = 40), proven strongyloidiasis patients (Group II, n = 100), and those with other parasitic infections (Group III, n = 154) were evaluated. Sensitivity and specificity were 81.0% and 84.0% for the NIE ICT kit, 89.0% and 83.5% for the SsIR ICT kit, and 95.0% and 90.2% for the NIE-SsIR ICT kit, respectively. The NIE-SsIR ICT kit provided the best diagnostic results; it can supplement stool examination for clinical diagnosis and can be used to screen for asymptomatic S. stercoralis infection in people at risk in endemic areas. The NIE-SsIR ICT kit can also be used in large-scale sero-epidemiological investigations in endemic areas without the need for additional facilities or ancillary supplies.

Strongyloides Hyper-Infection Syndrome and Ciliocytophthoria Mimicking Balantidium coli

Ciliocytophthoria is a phenomenon where degenerated cells in infections or malignancy can present as ciliated cells on microscopy and so may be confused with ciliated parasitic infection. We present an interesting case of recurrent shortness of breath, misdiagnosed as chronic obstructive pulmonary disease exacerbations leading to unnecessary exposure to antimicrobials and steroids. The case was diagnosed as Strongyloides hyper-infection syndrome. Another finding worth mentioning was that ciliated cells noted on broncho-alveolar lavage were thought to be a co-infection with Balantidium coli but were later confirmed as ciliocytophthoria.

LEARNING POINTS

Strongyloides hyper-infection syndrome should be considered in the differential diagnosis of a patient from an endemic area presenting with non-resolving respiratory symptoms.Ciliocytophthoria is a type of degenerative process where degenerated cells can appear ciliated on microscopy.Balantidium coli appears to be similar but is much larger and has cilia circumferentially compared with ciliocytophthoria which has a polar distribution of cilia.

Strongyloides Hyperinfection Associated with Enterococcus faecalis Bacteremia, Meningitis, Ventriculitis and Gas-Forming Spondylodiscitis: A Case Report

An elderly Singaporean male with no travel history was hospitalized for fever and altered mental status. Blood cultures grew Enterococcus faecalis, and given a preceding history of steroid use and peripheral eosinophilia, Strongyloides hyperinfection was suspected. Stool specimens were positive for Strongyloides stercoralis larvae over four days, and larvae were also isolated in an early morning nasogastric aspirate specimen prior to initiation of ivermectin. A cerebrospinal fluid examination was consistent with partially treated bacterial meningitis and ventriculitis was demonstrated on neuroimaging. In view of a persistent fever, a further imaging evaluation was performed, which demonstrated bilateral pneumonia as well as the unusual finding of gas-forming emphysematous spondylodiscitis and left psoas abscesses. Despite the early suspicion of Strongyloides hyperinfection, commencement of appropriate antibiotics and anti-helminthics, microbiological clearance of bacteremia as well as clearance of S. stercoralis from the stool, the patient still succumbed to infection and passed away 11 days after admission.

Co-infection with Strongyloides stercoralis hyperinfection syndrome and Klebsiella in a nephrotic syndrome patient: A case report

RATIONALE

Patients with chronic Strongyloides stercoralis infection are usually asymptomatic; therefore, their condition is easily overlooked. In immunosuppressed patients, mortality is high because of disseminated infection and hyperinfection. This report describes a fatal S stercoralis hyperinfection in a patient with nephrotic syndrome after treatment with steroids.

PATIENT CONCERNS

A 70-year-old male presented with a history of progressive edema, skin infection, persistent fever, cough, intermittent abdominal pain, and progressive respiratory failure after steroid treatment.

DIAGNOSIS

Nephrotic syndrome; cellulitis; S stercoralis hyperinfection; Klebsiella pneumonia.

INTERVENTIONS

During the first hospital admission, the patient was administered full-dose glucocorticoid and antibiotic therapy after suffering from cellulitis. During the second admission, he was diagnosed and treated for normal digestive discomfort and a bacterial infection. The patient had progressive respiratory failure and was placed on a ventilator. He was immediately treated with albendazole when S stercoralis was found in samples of his sputum and feces.

OUTCOMES

The patient died despite treatment with albendazole and antibiotic therapy.

LESSONS

It is essential to consider the possibility of S stercoralis infection in immunosuppressed patients with nephrotic syndrome. Given the lack of classic manifestations and high mortality rate of advanced disease, continuous monitoring, early diagnosis, and proper treatment are imperative.

Late post-kidney transplant Strongyloides hyperinfection syndrome

Disseminated strongyloidiasis is a potentially life-threatening infection in organ transplant recipients that typically occurs within the first 6 months of transplantation. We discuss a patient from the Appalachia region of Virginia who appeared to acquire Strongyloides stercoralis domestically years after kidney transplantation and then develop disseminated strongyloidiasis.

A Rare Case of Strongyloides Hyperinfection from Hypogammaglobulinemia

Strongyloides infection can range from asymptomatic eosinophilia to disseminated disease. Common in tropical and subtropical nations, it can lead to hyperinfection, an autoinfection increasing parasitic burden in immunocompromised. Cell-mediated immunity is important in combating parasite infection. We present a case of Strongyloides hyperinfection in hypogammaglobulinemia which was refractory to conventional treatment but responded to immunoglobulin administration with complete resolution indicating role of humoral immunity also.

Human infection with Strongyloides stercoralis and other related Strongyloides species

The majority of the 30-100 million people infected with Strongyloides stercoralis, a soil transmitted intestinal nematode, have subclinical (or asymptomatic) infections. These infections are commonly chronic and longstanding because of the autoinfective process associated with its unique life cycle. A change in immune status can increase parasite numbers, leading to hyperinfection syndrome, dissemination, and death if unrecognized. Corticosteroid use and HTLV-1 infection are most commonly associated with the hyperinfection syndrome. Strongyloides adult parasites reside in the small intestine and induce immune responses both local and systemic that remain poorly characterized. Definitive diagnosis of S. stercoralis infection is based on stool examinations for larvae, but newer diagnostics - including new immunoassays and molecular tests - will assume primacy in the next few years. Although good treatment options exist for infection and control of this infection might be possible, S. stercoralis remains largely neglected.

Detection of Strongyloides stercoralis infection among cancer patients in a major hospital in Kelantan, Malaysia

INTRODUCTION

Strongyloidiasis is one of the most commonly neglected but clinically important parasitic infections worldwide, especially among immunocompromised patients. Evidence of infection among immunocompromised patients in Malaysia is, however, lacking. In this study, microscopy, real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assays (ELISAs) were used to detect Strongyloides stercoralis (S. stercoralis) infection among cancer patients in a Malaysian hospital.

METHODS

A total of 192 stool and serum samples were collected from cancer patients who were receiving chemotherapy with or without steroid treatment at a hospital in northeastern Malaysia. Stool samples were examined for S. stercoralis using parasitological methods and real-time PCR. Serology by ELISA was performed to detect parasite-specific immunoglobulin G (IgG), IgG4 and immunoglobulin E (IgE) antibodies. For comparison, IgG4- and IgG-ELISAs were also performed on the sera of 150 healthy individuals from the same area.

RESULTS

Of the 192 samples examined, 1 (0.5%) sample was positive for S. stercoralis by microscopy, 3 (1.6%) by real-time PCR, 8 (4.2%) by IgG-ELISA, 6 (3.1%) by IgG4-ELISA, and none was positive by IgE-ELISA. In comparison, healthy blood donors had significantly lower prevalence of parasite-specific IgG (2.67%, p < 0.05) and IgG4 (2.67%, p < 0.05) responses.

CONCLUSION

This study showed that laboratory testing may be considered as a diagnostic investigation for S. stercoralis among immunocompromised cancer patients.

Disseminated strongyloidiasis in a patient with membranoproliferative glomerulonephritis-case report

Strongyloides stercoralis (SS) is a unique nematode with an auto infective cycle, so that it completes its life cycle within the human host and can live there for many years. In immunocompromised patients, infection can cause Strongyloides hyperinfection syndrome (S.H.S) that is associated with serious morbidity and mortality. As various infections are one of the leading causes of membranoproliferative glomerulonephritis (MPGN), we should consider subclinical strongyloidiasis as a possible underlying disease, especially in endemic areas. Here we describe a case of strongyloidiasis following immunosuppressive therapy for MPGN, the diagnosis of which was made, only a few hours before death, by stomach biopsy.

Strongyloides stercoralis hyperinfection presenting as subacute small bowel obstruction following immunosuppressive chemotherapy for multiple myeloma

We report the case of a 59-year-old Afro-Caribbean woman who presented with symptoms of anorexia, lethargy, abdominal distension and vomiting on the background of newly diagnosed multiple myeloma, treated with one cycle of cyclophosphamide-thalidomide-dexamethasone chemotherapy 20 days previously. A diagnosis of subacute bowel obstruction was made; however, the aetiology of the obstruction remained elusive. Common electrolyte abnormalities were excluded and a midline laparotomy revealed minimal intra-abdominal adhesions. Histological examination of a small bowel mesentery biopsy showed inflammatory cell infiltrate composed of lymphocytes, eosinophils and occasional plasma cells with a foreign body giant cell reaction suggestive of worm infection. A postoperative stool sample revealed heavy infestation with the rhabditiform larvae of Strongyloides stercoralis. The patient recovered following ivermectin treatment. In the absence of other causality, we attribute the subacute bowel obstruction to S stercoralis hyperinfection, triggered by immunosuppression secondary to chemotherapy and multiple myeloma.

Severe strongyloidiasis: a systematic review of case reports

BACKGROUND

Strongyloidiasis is commonly a clinically unapparent, chronic infection, but immuno suppressed subjects can develop fatal disease. We carried out a review of literature on hyperinfection syndrome (HS) and disseminated strongyloidiasis (DS), in order to describe the most challenging aspects of severe strongyloidiasis.

METHODS

We conducted a structured search using PubMed to collect case reports and short case series on HS/DS published from 1991 to 2011. We restricted search to papers in English, Spanish, Italian and French. Case reports were classified as HS/DS according to given definitions.

RESULTS

Records screened were 821, and 311 were excluded through titles and abstract evaluation. Of 510 full-text articles assessed for eligibility, 213 were included in qualitative analysis. As some of them were short case series, eventually the number of cases analyzed was 244.Steroids represented the main trigger predisposing to HS and DS (67% cases): they were mostly administered to treat underlying conditions (e.g. lymphomas, rheumatic diseases). However, sometimes steroids were empirically prescribed to treat signs and symptoms caused by unsuspected/unrecognized strongyloidiasis. Diagnosis was obtained by microscopy examination in 100% cases, while serology was done in a few cases (6.5%). Only in 3/29 cases of solid organ/bone marrow transplantation there is mention of pre-transplant serological screening. Therapeutic regimens were different in terms of drugs selection and combination, administration route and duration. Similar fatality rate was observed between patients with DS (68.5%) and HS (60%).

CONCLUSIONS

Proper screening (which must include serology) is mandatory in high - risk patients, for instance candidates to immunosuppressive medications, currently or previously living in endemic countries. In some cases, presumptive treatment might be justified. Ivermectin is the gold standard for treatment, although the optimal dosage is not clearly defined in case of HS/DS.

Screening, prevention, and treatment for hyperinfection syndrome and disseminated infections caused by Strongyloides stercoralis

PURPOSE OF REVIEW

This review discusses the latest approaches to the diagnosis and treatment of patients with strongyloidiasis, with an emphasis on infection in the immunocompromised host and the risk for disseminated strongyloidiasis.

RECENT FINDINGS

The differences in acute, chronic, accelerated autoinfection, and disseminated disease in Strongyloides stercoralis infection are explored with particular emphasis on early diagnosis, treatment, and prevention. The goals of treatment are investigated for the different infection states. Predisposing risks for dissemination are delineated, and the roles played for newer diagnostics in the identification of at-risk individuals are detailed.

SUMMARY

The use of newer diagnostic tests and broader screening of immunocompromised patients from Strongyloides-endemic areas is of paramount importance, particularly if prevention of life-threatening dissemination is the goal.

Strongyloidiasis-related deaths in the United States, 1991-2006

The objective of this study was to 1) assess the incidence of strongyloidiasis in the United States, 2) evaluate demographic and regional associations, and 3) identify comorbid conditions as risk factors for death. A population-based case-control study was performed by using mortality data during 1991-2006. We identified 347 strongyloidiasis deaths (0.79 per 10 million deaths, 14-29 deaths per year), which decreased slightly over time. Deaths occurred primarily among older (median age = 66.0 years), white (57.6%) and Hispanic (22.2%) men (69.2%), residing in the Southeastern United States (49.3%). Associated health conditions included chronic obstructive pulmonary disease (28.7%, odds ratio [OR] = 4.0, 95% confidence interval [CI] = 3.0-5.4) and infection with human immunodeficiency virus (12.5%, OR = 4.6, 95% CI = 2.7-7.9). Strongyloidiasis deaths in the second half of the study period (1999-2006) were less likely to be associated with chronic obstructive pulmonary disease (19.4%, OR = 1.2, 95% CI = 0.7-1.9), but continued to be associated with human immunodeficiency virus infection (12.9%, OR = 2.8, 95% CI = 1.3-6.0). Early detection and treatment of at-risk patients with latent strongyloidiasis infections is needed to reduce strongyloidiasis mortality.

Minimal change nephrotic syndrome in a patient with strongyloidiasis

Strongyloidiasis, a chronic infection caused by the intestinal parasite Strongyloides stercoralis, is prevalent in the Nansei Islands of Japan. Here, we report our findings on a case of strongyloidiasis complicated with steroid-resistant minimal change nephrotic syndrome in a 69-year-old male resident of Fukuoka Prefecture who had lived in Yakushima, one of the Nansei Islands, until age 15. In October 2006, he developed proteinuria and edema, and was diagnosed with minimal change nephrotic syndrome on the basis of the renal biopsy findings. Following treatment with prednisolone, the level of proteinuria decreased to 0.29 g/day by day 35. However, 5 days later (day 40), the patient developed persistent watery diarrhea and vomiting, leading to dehydration and malnutrition. Pneumonia and bacterial meningitis subsequently developed (day 146); filarial (infectious-type) and rhabditiform (noninfectious-type) S. stercoralis larvae were detected for the first time in the patient's sputum, gastric juice, feces, and urine. Although treatment with ivermectin was started immediately and the parasitosis responded to the treatment, the patient died of sepsis. Consequently, although strongyloidiasis is a rare infection except in endemic regions, it is essential to consider the possibility of this disease and begin treatment early for patients who have lived in endemic areas and who complain of unexplained diarrhea during steroid-induced or other immunosuppression.

Strongyloides stercoralis infection in the immunocompromised host

Strongyloides stercoralis is an intestinal nematode acquired in the tropics or subtropics. Most often, it causes chronic, asymptomatic infection, but a change in immune status can increase parasite numbers, leading to hyperinfection syndrome, dissemination, and death if unrecognized. Corticosteroid use is most commonly associated with hyperinfection syndrome. Diagnosis of Strongyloides infection is based on serology and serial stool examinations for larvae. The treatment of choice for chronic, asymptomatic infection is oral ivermectin. Alternative pharmacologic agents include albendazole and thiabendazole. For hyperinfection syndrome, ivermectin remains the drug of choice, though therapy duration must be individualized with the end point being complete parasite eradication. Recurrent strongyloidiasis should prompt an evaluation for human T-cell lymphotropic virus type 1 coinfection. No test of cure is currently available, although immunoglobulin G antibody levels have been shown to decline within 6 months of successful treatment.

Strongyloides stercoralis and the immune response

The immune system is a highly evolved network of cells and molecules that can distinguish between invading pathogens and the body's own cells. But helminths, in their complex forms, are capable of down-regulating host immunity, protecting them from being eliminated and also minimizing severe pathology in the host. This review focuses on Strongyloides stercoralis and the immune responses in immunocompetent and/or immunocompromised individuals. It also highlights the implications for diagnosis/treatment and draws attention to an emerging public health disease. The solution to reducing the prevalence of strongyloidiasis remains on the effectiveness of pre-emptive measures in endemic communities, increased awareness, prompt early diagnosis as well as timely treatment.

Manifestations, diagnosis, and treatment of Strongyloides stercoralis infection

OBJECTIVE

To summarize current literature on the manifestations, diagnosis, and treatment of Strongyloides stercoralis infection.

DATA SOURCES

A search was conducted of PubMed (1970-August 2007). Search terms included Strongyloides stercoralis, hyperinfection, prevention, and treatment. Reviews, studies, and recent case reports were included. Additional references were obtained from article bibliographies.

STUDY SELECTION AND DATA EXTRACTION

All studies or review articles published in English from 1970 to August 2007 and case reports of hyperinfection or disseminated disease published since 2000 were evaluated.

DATA SYNTHESIS

Strongyloidiasis is a parasitic infection endemic to tropical, subtropical, and temperate areas including the Appalachian region of the southern US. Prevalence rates vary widely. Patients may present with infection decades after original exposure. Diagnosis can be achieved by identifying the larvae in the stool; usually, more than one sample is needed. Most patients are asymptomatic. However, in immunosuppressed patients, a hyperinfection syndrome or disseminated disease may occur due to the ability of the parasite to reproduce within the host. The most common risk factors for these complications are immunosuppression caused by corticosteroids and infection with human T lymphotropic virus type 1. Treatment options for uncomplicated disease include thiabendazole, ivermectin, and albendazole. Thiabendazole has been replaced by ivermectin as treatment of choice due to better tolerance. These antihelminthics have been used to treat hyperinfection or disseminated disease alone or in combination, but data are limited to case reports or case series. Prevention of disease is mainly achieved by wearing shoes in endemic areas to avoid contact with infected soil.

CONCLUSIONS

Strongyloides is a unique parasite that can cause a hyperinfection syndrome and disseminated infection several years after exposure. Treatment options include ivermectin, thiabendazole, or albendazole. Information on the best treatment for disseminated disease and hyperinfection is limited.