Fatal septicemic shock associated with Strongyloides stercoralis infection in a patient with angioimmunoblastic T-cell lymphoma: a case report and literature review

Severe strongyloidiasis: a systematic review and meta-analysis of 339 cases

Strongyloidiasis is a parasitosis representing a significant public health problem in tropical countries. It is often asymptomatic in immunocompetent individuals but its mortality rate increases to approximately 87% in severe forms of the disease. We conducted a systematic review, including case reports and case series, of Strongyloides hyperinfection and dissemination from 1998 to 2020 searching PubMed, EBSCO and SciELO. Cases that met the inclusion criteria of the Preferred Reported Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist were analysed. Statistical analysis was performed using Fisher's exact test and Student's t-test and a Bonferroni correction for all the significant values. A total of 339 cases were included in this review. The mortality rate was 44.83%. The presence of infectious complications, septic shock and a lack of treatment were risk factors for a fatal outcome. Eosinophilia and ivermectin treatment were associated with an improved outcome.

Overlapping Infection by Strongyloides spp. and Cytomegalovirus in the Immunocompromised Host: A Comprehensive Review of the Literature

Strongyloides and cytomegalovirus co-infections are rarely reported, even though they are distinguished by high morbidity and mortality, especially in immunocompromised hosts. We narratively reviewed the literature on reported cases of Strongyloides and CMV co-infections in immunosuppressed patients. Most cases occurred in males with a median age of 47 (IQR, 37-59). Strongyloides/CMV co-infections occurred among immunocompromised hosts, especially in solid organ transplants and hematological or rheumatological diseases. Most of the patients underwent a course of steroid treatment before the diagnosis of co-infections. Other common immunomodulatory agents were tacrolimus and mycophenolate. The first clinical manifestations of co-infections were mainly gastrointestinal, followed by respiratory symptoms. CMV was, in most patients, co-infected with an isolated reactivation, although Strongyloides manifested especially as hyperinfection syndrome. Ganciclovir and ivermectin are the mainstays of CMV and Strongyloides treatment. However, the treatment mortality reported in this narrative review is around 52.4%. Interestingly secondary bacterial infections are common in CMV/Strongyloides-infected patients.

A Description of the Type, Frequency and Severity of Infections Among Sixteen Patients Treated for T-Cell Lymphoma

Background

Infections are an important cause of morbidity and mortality in T-cell lymphomas. Factors contributing to increased risk of infection include the nature of the underlying disease, as well as treatment-associated immunosuppression. Currently there are few reports describing the types of infections, including preventable infections, in this cohort of patients. The aim of the study was to identify the type, frequency and severity of infection in patients with T-cell lymphoma undergoing treatment.

Methods

A case series was performed on all patients with T-cell lymphoma over a 5-year period from 2011 to 2016 at a tertiary Australian hospital. Information was collected from medical record review regarding patient demographics, lymphoma treatment and outcomes, and infectious outcomes. Severe infections were recorded, defined as infection requiring hospitalization.

Results

Sixteen patients were identified with a diagnosis of T-cell lymphoma who received treatment at our institution. There were 42 discrete episodes of severe infections in total. Severe infections occurred in 81% of patients, with over 40% having more than one infection. The median length of hospital stay was 13 days, 33% required intensive care admission and 14% of infectious episodes resulted in death. Only 50% of infectious episodes were microbiologically proven, with the most common etiology being bacterial. The most commonly isolated organism overall was Staphylococcus aureus, with the most common source of infection being skin and soft tissue. There was one case of cytomegalovirus (CMV) infection and five cases (12%) of invasive fungal infection. The highest rates of infection occurred during progressive disease. Rates of prophylaxis were highest with antiviral agents, and comparatively lower with antibacterial and antifungal agents.

Conclusion

Infections are frequent, opportunistic and severe in patients with T-cell lymphoma. Our data suggests that fungal prophylaxis may be indicated with T-cell lymphoma.

Fatal strongyloidiasis after corticosteroid therapy for presumed chronic obstructive pulmonary disease

INTRODUCTION

Strongyloidiasis is a neglected tropical disease with global prevalence. Under some cases of immune suppression (especially with corticosteroid administration), the nematode involved disseminates, leading to an amplified, possibly lethal hyper-infection syndrome.

CASE PRESENTATION

A 56-year-old Nepalese man presenting with chief complaints of nausea, vomiting, joint pain and abdominal cramps was admitted to Sumeru Hospital. His past history revealed: chronic obstructive pulmonary disease (COPD), systemic hypertension and previously treated pulmonary tuberculosis. The patient had been treated with oral prednisolone (60 mg gl-1) for 8 days due to a presumed exacerbation of his COPD. Sequentially, he developed haemoptysis, chest tightness, frequent wheezing and worsening cough. Bronchoscopy showed severe diffuse alveolar haemorrhage; microbiological examination of broncho-alveolar lavage (BAL) was recommended. Examination of an acid fast bacilli stain preparation of BAL revealed filariform larvae of Strongyloides. Stool specimen examination revealed larvae of Strongyloides. The physical condition of the patient began to deteriorate; a few days after admission, vancomycin-sensitive Enterococcus faecium was isolated from a blood sample. He was treated with ivermectin and albendazole for strongyloides and linezolid plus vancomycin for E. faecium. However, the patient failed to recover from the illness and died.

CONCLUSION

The findings of our study suggest that corticosteroid administration in strongyloidiasis can lead to the development of fatal strongyloides hyper-infection syndrome. Hence our experience suggests the need for early diagnosis of strongyloidiasis to avoid such an outcome. A deterioration of the patient's condition after the initiation of corticosteroid therapy in endemic areas should raise the possibility of strongyloidiasis.

Strongyloidiasis Current Status with Emphasis in Diagnosis and Drug Research

Strongyloidiasis is a parasitic neglected disease caused by the nematode Strongyloides stercoralis affecting 30 to 100 million people worldwide. Complications, strongly associated with alcoholism, organ transplants, and HTLV-1 virus, often arise due to late diagnosis, frequently leading to patient death. Lack of preemptive diagnosis is not the only difficulty when dealing with this parasite, since there are no gold standard diagnostic techniques, and the ones used have problems associated with sensitivity, resulting in false negatives. Treatment is also an issue as ivermectin and benzimidazoles administration leads to inconsistent cure rates and several side effects. Researching new anti-Strongyloides drugs is a difficult task since S. stercoralis does not develop until the adult stages in Mus musculus (with the exception of SCID mice), the main experimental host model. Fortunately, alternative parasite models can be used, namely, Strongyloides ratti and S. venezuelensis. However, even with these models, there are other complications in finding new drugs, which are associated with specific in vitro assay protocol steps, such as larvae decontamination. In this review, we highlight the challenges associated with new drug search, the compounds tested, and a list of published in vitro assay methodologies. We also point out advances being made in strongyloidiasis diagnosis so far.

A case of fatal gastrointestinal haemorrhage due to hyperinfection with Strongyloides stercoralis

Strongyloides stercoralis is an intestinal nematode with a complex life cycle. It is usually asymptomatic in healthy host however it may be a life threatening condition in immunocompromised patients when hyperinfection is associated with disseminated disease. However, reports of gastric involvement are rare. This is a case report of fatal gastrointestinal hemorrhage due to hyperinfection with S. stercoralis in a Burmawi male patient after brief corticosteroid therapy.

Löffler syndrome on a Louisiana pig farm

Löffler syndrome, a fulminant eosinophilic pneumonitis associated with the larval migratory phase of human parasites, is rarely reported in the United States. A previously healthy 8-year-old male was hospitalized with tachypnea, cough, hypoxemia, and fever of one week's duration. History revealed exposure to pigs on his family's farm in southernmost Louisiana, where the patient was responsible for cleaning the farm's pigpens. His fingernails were soiled and extremely short, with the edge of the nail bed exposed secondary to onychophagia. Laboratory evaluation demonstrated peripheral eosinophilia (39%), pulmonary eosinophilia (86%), high total IgE, diffuse reticulonodular lung opacities, and mixed obstructive and restrictive pulmonary function pattern. Systemic corticosteroids were initiated for his acute respiratory insufficiency and produced rapid clinical improvement. Serum Ascaris-specific IgE was markedly elevated and he was treated with albendazole. An extensive evaluation for other infectious and allergic etiologies was negative. A site visit to the family farm and laboratory investigation was coordinated with the Louisiana Animal Disease Diagnostic Laboratory at LSU. Ascaris suum eggs were detected in fresh pig feces and in the soil immediately surrounding the pens. Ascariasis should be considered even in the absence of travel history, especially in swine raising areas that are endemic for Ascaris in pigs, such as the southeastern United States. Onychophagia is a highly probable mechanism of zoonotic fecal-oral transmission in this case, and such habits could lead to continual reinfection. Systemic corticosteroids were effective in treating the patient's acute respiratory compromise due to Löffler syndrome.

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.

Treatment with nitric oxide donors diminishes hyperinfection by Strongyloides venezuelensis in mice treated with dexamethasone

The effects of using nitric oxide (NO) donors and inhibitors in experimental strongyloidiasis were showed using, both naïve and dexamethasone immunosuppressed BALB/c mice infected with Strongyloides venezuelensis. Aminoguanidine, an inhibitor of inducible NO synthase and LA419 a NO donor, were administered. Dexamethasone was used to induce immunosuppression. The study in BALB/c mice revealed increases in counts of fecal eggs, larvae in lungs and parasitic females following treatment with aminoguanidine, while mice treated with LA419 had limited egg output with low larval and adult recoveries. Mice immunosuppressed with dexamethasone developed hyperinfection with high long lasting fecal egg emission, high numbers of larvae in lungs and high numbers of parasitic females in the intestine even when the infection had already been cleared in non-immunosuppressed infected controls. Mice treated with dexamethasone and aminoguanidine had the highest egg output and the highest larva and parasitic female recovery showing a severe hyperinfection syndrome. In contrast, treatment with dexamenthasone and LA419 resulted in a controlled hyperinfection syndrome and these mice were able to eliminate the parasite. Therefore, NO modulation appears to be a determinant factor in severe strongyloidiasis and further studies should be conducted to confirm in other experimental models.

Strongyloidiasis with emphasis on human infections and its different clinical forms

Strongyloidiasis (caused by Strongyloides stercoralis, and to a lesser extent by Strongyloides fuelleborni) is one of the most neglected tropical diseases with endemic areas and affecting more than 100 million people worldwide. Chronic infections in endemic areas can be maintained for decades through the autoinfective cycle with the L3 filariform larvae. In these endemic areas, misdiagnosis, inadequate treatment and the facilitation of the hyperinfection syndrome by immunosuppression are frequent and contribute to a high mortality rate. Despite the serious health impact of strongyloidiasis, it is a neglected disease and very little is known about this parasite and the disease when compared to other helminth infections. Control of the disease is difficult because of the many gaps in our knowledge of strongyloidiasis. We examine the recent literature on different aspects of strongyloidiasis with emphasis in those aspects that need further research.

A case of Strongyloides hyperinfection associated with tuberculosis

Strongyloidiasis is a parasitic infection that occurs in tropical regions. Hyperinfection, which is an accelerated autoinfection, is often associated with an immunosuppressive state, such as HTLV-1 infection or steroid use. Immunosuppression can also lead to reactivation of tuberculosis infection. These infections may have interacted as a result of impaired cellular immunity. A 28-year-old Nepali male was referred to our hospital for slight abdominal pain and high fever. An abdominal CT scan showed ascites and intestinal swelling. He was admitted with suspected gastroenteritis. Results of stool microscopy on the third day of hospitalization revealed abundant strongylid larvae. We diagnosed a Strongyloides hyperinfection and prescribed ivermectin. Although the numbers of strongylid organisms in the patient’s stool soon diminished, his temperature remained high. After receiving a second dose of ivermectin on day 17, he was transferred to a nearby hospital for observation, where he was noted to have massive pleural effusion. He returned to our hospital where his pleural effusion was found to be positive for adenosine deaminase (ADA), and he was diagnosed with a tuberculosis infection. Strongyloides hyperinfection can occur in a non-endemic region. It can be associated with tuberculosis infection possibly due to impaired cellular immunity. It is important to consider other possible infections when treating a patient with an infection associated with impaired cellular immunity.

Helminths and their implication in sepsis - a new branch of their immunomodulatory behaviour?

The prevalence of autoimmune and allergic disorders has dramatically increased in developed countries, and it is believed that our ‘cleaner living’ reduces exposure to certain microorganisms and leads to deviated and/or reduced regulation of the immune system. In substantiation of this health hygiene hypothesis, multiple epidemiological studies and animal models have characterized the protective immune responses induced by helminths during auto-inflammatory disorders. The beneficial effects of such helminths, like schistosomes and filariae, are thought to lie in their immunomodulatory capacity, which can be induced by different life-cycle stages or components thereof. In addition to suppressing autoimmunity recent evidence indicates that concurrent helminth infections also counterbalance exacerbated pro-inflammatory immune responses that occur during sepsis, improving survival. As with allergy, epidemiological studies have observed a steady rise in severe sepsis cases and although this may have resulted from several factors (immunosuppressive drugs, chemotherapy, transplantation, increased awareness and increased surgical procedures), it is tempting to hypothesize that the lack of helminth infections in Western countries may have contributed to this phenomenon. This review summarizes how helminths modulate host immunity during sepsis, such as manipulating macrophage activation and provides an overview about the possible implications that may arise during overwhelming bacterial co-infections.

This well written review gives a comprehensive overview on the immunopathology of sepsis and the modulation of immune responses by helminths. It provides evidence that helminths or components thereof may improve the outcome of severe infections. This will allow the development of therapeutic strategies to fight infections and sepsis.