Strongyloides in bronchoalveolar lavage fluid: practical implications in the COVID-19 era

Cost-effectiveness of treatment strategies for populations from strongyloidiasis high-risk areas globally who will initiate corticosteroid treatment in the USA

BACKGROUND

The risk of developing strongyloidiasis hyperinfection syndrome appears to be elevated among individuals who initiate corticosteroid treatment. Presumptive treatment or treatment after screening for populations from Strongyloides stercoralis-endemic areas has been suggested before initiating corticosteroids. However, potential clinical and economic impacts of preventative strategies have not been evaluated.

METHODS

Using a decision tree model for a hypothetical cohort of 1000 individuals from S. stercoralis-endemic areas globally initiating corticosteroid treatment, we evaluated the clinical and economic impacts of two interventions, 'Screen and Treat' (i.e. screening and ivermectin treatment after a positive test), and 'Presumptively Treat', compared to current practice (i.e. 'No Intervention'). We evaluated the cost-effectiveness (net cost per death averted) of each strategy using broad ranges of pre-intervention prevalence and hospitalization rates for chronic strongyloidiasis patients initiating corticosteroid treatment.

RESULTS

For the baseline parameter estimates, 'Presumptively Treat' was cost-effective (i.e. clinically superior with cost per death averted less than a threshold of $10.6 million per life) compared to 'No Intervention' ($532 000 per death averted) or 'Screen and Treat' ($39 000 per death averted). The two parameters contributing the most uncertainty to the analysis were the hospitalization rate for individuals with chronic strongyloidiasis who initiate corticosteroids (baseline 0.166%) and prevalence of chronic strongyloidiasis (baseline 17.3%) according to a series of one-way sensitivity analyses. For hospitalization rates ≥0.022%, 'Presumptively Treat' would remain cost-effective. Similarly, 'Presumptively Treat' remained preferred at prevalence rates of ≥4%; 'Screen and Treat' was preferred for prevalence between 2 and 4% and 'No Intervention' was preferred for prevalence <2%.

CONCLUSIONS

The findings support decision-making for interventions for populations from S. stercoralis-endemic areas before initiating corticosteroid treatment. Although some input parameters are highly uncertain and prevalence varies across endemic countries, 'Presumptively Treat' would likely be preferred across a range for many populations, given plausible parameters.

Human Strongyloides stercoralis infection

Strongyloides stercoralis is an important soil-transmitted helminth occurring world-wide and affecting 30-100 million people. Because many cases are asymptomatic and sensitive diagnostic methods are lacking, S. stercoralis infection is frequently underdiagnosed. The increasing incidence of autoimmune and wasting diseases and increased use of immunosuppressive agents, as well as the increased use of immunosuppressants and cytotoxic drugs, have increased S. stercoralis infection and their mortality. This review provides information about S. stercoralis epidemiology, life cycle, aetiology, pathology, comorbidities, immunology, vaccines, diagnosis, treatment, prevention, control and makes some recommendations for future prevention and control of this important parasite.

Strongyloides coinfection in COVID-19 patients treated with corticosteroids: A systematic review

The COVID-19 pandemic linked to the virus SARS-CoV-2, which began in China, affected ∼765 million people as of 30 April 2023. The widespread use of corticosteroids for the symptomatic treatment of COVID-19 could lead to the reactivation of infections of opportunistic pathogens, including Strongyloides. We sought to determine the clinical symptoms and demographic characteristics of SARS-CoV-2-Strongyloides co-infection, particularly in patients with severe disease and being treated with immunosuppressive drugs. To do this, we undertook a systematic review of the literature, and searched public accessible scientific databases-the Web of Science, Scopus, PubMed/Medline and Embase -for eligible studies (1 December 2019 to 30 August 2022). The review protocol is registered in PROSPERO (CRD42022377062). Descriptive statistical analyses were used to present the clinical and laboratory parameters of the co-infection; for this, we calculated prevalence using the following formula: positive cases/total number of cases × 100. Of a total of 593 studies identified, 17 studies reporting 26 co-infected patients met the criteria for inclusion in this review. The median age of these patients was 55.14 years. Most of cases (53.8%) were treated with dexamethasone, followed by methylprednisolone (26.9%). Eighteen of 26 patients were immigrants living in European countries or the USA; most of these immigrants originated from Latin America (58%) and South-East Asia (11%). The commonest symptoms of co-infection were abdominal pain (50%), fever (46.1%), dyspnoea (30.7%) and cough (30.7%), and frequently reported laboratory findings were high absolute eosinophil count (38.4%), high white blood cell count (30.7%), high C-reactive protein (23.0%) and high neutrophil count (19.2%). Two of the 26 patients (7.7%) had fatal outcomes. Most of the SARS-CoV-2-Strongyloides coinfected cases were immigrants living in developed countries, emphasising the need for clinicians in these countries to be aware of clinical and laboratory parameters associated with such co-infections, as well as the key importance of rapid and accurate diagnostic tests for timely and effective diagnosis and patient management.

Importance of Balanced Attention Toward Coronavirus Disease 2019 and Neglected Tropical Diseases

Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, has been spreading since 2019, causing a worldwide pandemic. Amid the COVID-19 pandemic, tuberculosis, AIDS, and malaria have adversely affected the quality of life of patients and killed millions of people. In addition, COVID-19 continues to impede the delivery of health services, including those for the control of neglected tropical diseases (NTDs). Furthermore, NTDs have been reported as possible co-pathogens among patients infected with COVID-19. However, studies regarding parasitic co-infection among these patients have been limited. This review aimed to explore and describe the cases and reports of parasitic infections in the backdrop of COVID-19 to provide comprehensive knowledge regarding this aspect. We reviewed seven cases of patients who had parasitic co-infection and tested positive for COVID-19, and summarized the literature on the importance of controlling parasitic diseases. In addition, we identified recommendations for the control of parasitic diseases under possible difficulties, such as declining funding for parasitic diseases in 2020. This review highlights the growing burden of NTDs under COVID-19 that may be caused by the deficiency of healthcare infrastructure and human resources as the main reasons. Clinicians should remain vigilant for possible co-infections with parasites in COVID-19 patients, while policymakers are urged to reinforce a balanced and long-term health strategy that addresses both NTDs and COVID-19.

Strongyloidiasis-related lung involvement: too much of a bad thing

PURPOSE OF REVIEW

Strongyloidiasis is a soil-transmitted helminthiasis, a neglected tropical disease that affects 300-900 million individuals globally. Strongyloides stercoralis is associated with cutaneous, respiratory, and gastrointestinal clinical manifestations. Chronicity is due to an autoinfective cycle, and host immunosuppression can lead to severe and fatal disease. Lung involvement is significant in severe strongyloidiasis, and Strongyloides has a complex association with a number of lung diseases, which will be discussed in this review.

RECENT FINDINGS

The treatment of chronic lung diseases such as asthma and chronic obstructive pulmonary disease with corticosteroids is an important risk factor for Strongyloides hyperinfection syndrome (SHS)/disseminated strongyloidiasis. The use of corticosteroids in the treatment of coronavirus disease 2019 (COVID-19) and potentially COVID-19-induced eosinopenia are risk factors for severe strongyloidiasis. Recent findings have demonstrated a significant immunomodulatory role of Strongyloides in both latent and active pulmonary tuberculosis associated to an impaired immune response and poor outcomes in active pulmonary tuberculosis.

SUMMARY

Strongyloides lung involvement is a common finding in severe infection. Prompt recognition of Strongyloides infection as well as prevention of severe disease by screening or presumptive treatment are important goals in order to improve Strongyloides outcomes in at-risk population.

Strongyloides Hyperinfection Syndrome among COVID-19 Patients Treated with Corticosteroids

Widespread use of corticosteroids for COVID-19 treatment has led to Strongyloides reactivation and severe disease in patients from endemic areas. We describe a US patient with COVID-19 and Strongyloides hyperinfection syndrome and review other reported cases. Our findings highlight the need for Strongyloides screening and treatment in high-risk populations.

Strongyloidiasis in immunocompromised migrants to non-endemic countries in the era of COVID-19: what is the role for presumptive ivermectin?

The COVID-19 pandemic has led to widespread use of dexamethasone. Corticosteroid therapy is an important risk factor for Strongyloides hyperinfection. Challenges associated with the performance of Strongyloides tests, and the poor availability of high quality and timely diagnostic testing, makes the use of presumptive ivermectin reasonable in selected situations.