Loiasis, Lymphatic Filariasis
Conditions
Keywords
diagnostics, cross-reactivity
Brief summary
This prospective study will enroll and follow 60 loiasis patients with high worm burden to monitor the spontaneous release of filarial antigen in peripheral blood. This study will define the cross-reactive antigen profile of persons with spontaneous loiasis antigenemia, and determine whether it varies with time.
Detailed description
Global efforts to eradicate lymphatic filariasis (LF) depend on rapid diagnostic tests (RDTs) that detect Wuchereria bancrofti circulating filarial antigen but these tests are unreliable in African nations where Loa loa is co-endemic because they yield false-positive results in some individuals with loiasis. The goals of this project are to define the cross-reactive antigen profile of persons with spontaneous antigenemia, how it varies over time, and to determine which L. loa antigens in cross-reactive sera best distinguish loiasis cross-reactivity from LF. This prospective study will prospectively enroll 50 adults who presented with cross-reactive antigenemia at screening and 10 negative controls. Participants will followed for one year and tested every three months for persistence of antigenemia.
Interventions
OTHERNo intervention
Patients in these cohorts will not be given anti-filariasis therapies because these drugs are not approved for use in patients with high worm burdens (\>20,000 Mf/mL)
Sponsors
Washington University School of Medicine
Doris Duke Charitable Foundation
Center for Research on Filariasis and Other Tropical Diseases, Cameroon
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Ability to give informed consent * Loiasis Mf count \> 20,000 Mf/mL * Resident of study area * No evidence of severe or systemic comorbidities * Consent to storage of blood samples for future study
Exclusion criteria
* Subject plans to move from the study area during subsequent 12 months
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| prevalence of specific cross-reactive L. loa antigens at baseline | 1 day | Prevalence of filariasis test strip (FTS) positive individuals at screening. Cross-reactive proteins in plasma will be identified by mass-spectrometry to identify a cross-reactive biomarker |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Recurrence of cross-reactive antigenemia | quarterly for 1 year | To determine if the same antigens are present at each follow up |
Countries
Cameroon
Contacts
PRINCIPAL_INVESTIGATORPhilip Budge, MD, PhD
Washington University School of Medicine
Outcome results
None listed