Strongyloides Stercoralis in Bone Marrow Transplant Recipients in the UK

Study Overview
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Brief Summary
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Strongyloidiasis is a worm infection which affects more than 100 million people, mostly in Africa, Asia and Latin America, and can cause severe illness in people with reduced immunity. In the UK, the number of people with Strongyloides is not known. At Imperial College Healthcare NHS Trust (ICHNT) , screening for Stongyloides has recently been introduced as a standard-of-care for all patients undergoing BMT. In this study, investigators will perform two cross-sectional surveys and report the prevalence of Strongyloides in BMT recipients at ICHNT , as well as comparing clinical outcomes before/after the introduction of routine testing.

Detailed Description
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Strongyloidiasis is a worm infection which affects more than 100 million people, mostly in Africa, Asia and Latin America. Infection can persist for decades, and usually causes mild symptoms. In some people with reduced immune systems (for example those who have bone marrow transplantation), the worms can multiply and cause severe illness and death. In the UK, the number of people with Strongyloides is not known. However, in many other non-tropical countries, rates are high in immigrant populations (including those who are having bone marrow transplantation, BMT). At ICHNT, screening for Stongyloides has recently been introduced as a standard-of-care for all patients undergoing BMT. All adult patients with forthcoming BMT at ICHNT will now be screened. Additionally, any patients who have already undergone BMT in the last two years will be screened as part of a look-back exercise as part of their clinical care. In this study, investigators will perform two cross-sectional surveys. Those who underwent BMT between Jun 2018 - July 2020 will form a 'pre-screening group', and those between July 2020 - July 2021 will form a 'screened group'. It is anticipated that 320 participants will be included in the pre-screening group and 160 in the screened-group (total 480). Data will be collected retrospectively and the prevalence of Strongyloides in BMT recipients at ICHNT will be reported. Comparison of clinical outcomes between the first and second groups will be undertaken, in order to determine whether the introduction of screening has had an impact.

Official Title
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Seroprevalence and Impact of Screening for Strongyloides Stercoralis in Bone Marrow Transplant Recipients in the UK

Conditions
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Strongyloidiasis, Bone Marrow Transplant Infection

Intervention / Treatment
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* Other: None - standard of care


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients Under care of Haematology at ICHNT Undergoing BMT Jun 2018 - July 2020 ('pre-screening group') or July 2020 - July 2021 ('screened group') Exclusion Criteria: Age < 18 years (i.e. managed as paediatric BMT) Previous BMT but no Strongyloides serology result available at the time of data collection

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Pre-screening group<br>Individuals undergoing bone marrow transplantation Jun 2018 - July 2020 | Other: None - standard of care<br>* Observational study only. Pre-screening group were not screened for Strongyloides, as per the standard of care at the time. Screened group were screened for Strongyloides, because the standard of care at our centre changed.<br>|
| Screened group<br>Individuals undergoing bone marrow transplantation July 2020 - July 2021 | Other: None - standard of care<br>* Observational study only. Pre-screening group were not screened for Strongyloides, as per the standard of care at the time. Screened group were screened for Strongyloides, because the standard of care at our centre changed.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Strongyloides seropositivity |  | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| BMT outcome | Bloodstream infection | Within first 12 months after BMT | 
| BMT outcome | Respiratory disease | Within first 12 months after BMT | 
| BMT outcome | Clinically significant diarrhoea | Within first 12 months after BMT | 
| BMT outcome | CNS infection | Within first 12 months after BMT | 
| BMT outcome | Graft vs. host disease | Within first 12 months after BMT | 
| BMT outcome | Length-of-hospital-stay | Within first 12 months after BMT | 
| BMT outcome | Antibiotic usage (defined daily doses) | Within first 12 months after BMT | 
| BMT outcome | ICU admission | Within first 12 months after BMT | 
| BMT outcome | Strongyloides hyperinfection syndrome | Within first 12 months after BMT | 
| BMT outcome | Mortality | Within first 12 months after BMT |