Onchocerciasis
Conditions
Keywords
mass drug administration, ophthalmology
Brief summary
The DOLF Ocular Changes after Ivermectin study will investigate the kinetics of O. volvulus microfilaria (Mf) in the eye following treatment with ivermectin. The primary objective is to determine the proportion of participants with complete Mf clearance from the eye at 3 and 6 months following treatment with ivermectin (IVM).
Detailed description
This study will examine the kinetics of Mf clearance in the eye following ivermectin treatment. Previous studies have been unable to fully assess clearance Mf from the posterior chamber of the eye. This study will be the first to use optical coherence tomography (OCT) in patients with onchocerciasis to document parasites and pathology in the anterior and posterior chambers of the eye, and assess ocular changes following standard ivermectin treatment. This will be a biomedical prospective cohort study. The cohort will be stratified based on Mf levels to achieve approximately the following distribution of individuals with roughly one-third of participants in each group. 1. Individuals with positive skin snip Mf density of ≥ 1 Mf/mg), but no observable Mf in eyes using slit lamp and indirect ophthalmoscopy 2. Individuals with positive skin snip Mf density of ≥ 1 Mf/mg and 1-10 Mf in either eye at baseline (based on the highest number counted in either eye) 3. Individuals with positive skin snip Mf density of ≥ 1 Mf/mg and \>10 Mf in either eye at baseline. All participants recruited into the study will be treated with a single dose of ivermectin (150 ug/kg) by mouth under direct observation. This is the standard of care for treatment with onchocerciasis. Participants will be evaluated following treatment with detailed parasitological and ocular examinations 7 days, 3 months and 6 months after treatment.
Interventions
ivermectin tablet
Sponsors
Study design
Intervention model description
Participants are all given a standard treatment (ivermectin) for onchocerciasis.
Eligibility
Inclusion criteria
* Have at least 1 palpable subcutaneous nodule (onchocercoma) and ≥ 1 Mf/mg of skin (by skin snip)
Exclusion criteria
* Pregnancy and breastfeeding mothers within 1 month of giving birth * Have base line eye diseases including glaucoma, uveitis, severe keratitis, and/or cataracts that interfere with visualization of the posterior segment of the eye. * Prior allergic / hypersensitivity reactions or intolerance to ivermectin * Treatment with ivermectin in the past 6 (six) months
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of participants with complete microfilaria clearance from the eye at 6 months | 6 months following treatment | Microfilaria in the anterior chamber of the eye will be counted during slit lamp examination at time of assessment. Participants without Mf in the eye will be considered clear of infection in the eye. |
| Number of participants with complete microfilaria clearance from the eye at 3 months | 3 months following treatment | Microfilaria in the anterior chamber of the eye will be counted during slit lamp examination at time of assessment. Participants without Mf in the eye will be considered clear of infection in the eye. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The change from baseline in the number of microfilaria detected in the skin at 6 months | baseline, and 6 months following treatment | Microfilaria (Mf) in the skin will be detected by skin snip microscopy. Up to four (4) skin snips using a corneoscleral punch will be weighed on an analytical balance and incubated for at least 8 hours in isotonic saline in a well of a flat-bottomed microtitre plate at ambient temperature. The Mf that have emerged will be counted using a microscope. Mf number and skin snip weight will be recorded. The mean skin microfilarial density will be calculated and recorded as mf/mg. |
| The change from baseline in the number of microfilaria detected in the eye at 3 months | baseline, 3 months following treatment | Microfilaria in the anterior chamber of the eye will be counted during slit lamp examination at time of assessment. |
| The change from baseline in the number of microfilaria detected in the skin at 3 months | baseline, and 3 months following treatment | Microfilaria (Mf) in the skin will be detected by skin snip microscopy. Up to four (4) skin snips using a corneoscleral punch will be weighed on an analytical balance and incubated for at least 8 hours in isotonic saline in a well of a flat-bottomed microtitre plate at ambient temperature. The Mf that have emerged will be counted using a microscope. Mf number and skin snip weight will be recorded. The mean skin microfilarial density will be calculated and recorded as mf/mg. |
| The change from baseline in the number of microfilaria detected in the eye at 6 months | baseline, 6 months following treatment | Microfilaria in the anterior chamber of the eye will be counted during slit lamp examination at time of assessment. |
| Number of participants with complete microfilaria clearance from the skin at 3 months | 3 months following treatment | Microfilaria (Mf) in the skin will be detected by skin snip microscopy. Up to four (4) skin snips using a corneoscleral punch will be weighed on an analytical balance and incubated for at least 8 hours in isotonic saline in a well of a flat-bottomed microtitre plate at ambient temperature. The Mf that have emerged will be counted using a microscope. Mf number and skin snip weight will be recorded. Participants without Mf in the skin will be considered clear of infection in the skin. |
| Number of participants with complete microfilaria clearance from the skin at 6 months | 6 months following treatment | Microfilaria (Mf) in the skin will be detected by skin snip microscopy. Up to four (4) skin snips using a corneoscleral punch will be weighed on an analytical balance and incubated for at least 8 hours in isotonic saline in a well of a flat-bottomed microtitre plate at ambient temperature. The Mf that have emerged will be counted using a microscope. Mf number and skin snip weight will be recorded. Participants without Mf in the skin will be considered clear of infection in the skin. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Assess the utility of optical coherence tomography for evaluating the presence and clearance of Mf in the anterior and posterior segments of the eye. | baseline, 3 and 6 months following treatment | Results from the optical coherence tomography (OCT) will be compared with slit lamp and other ocular examinations |
| Evaluate ocular changes between baseline and 3 months following ivermectin treatment using OCT | baseline, and 3 months following treatment | Results from the optical coherence tomography (OCT) will be compared in participants pre and post treatment |
| Evaluate ocular changes between baseline and 6 months following ivermectin treatment using OCT | baseline, and 6 months following treatment | Results from the optical coherence tomography (OCT) will be compared in participants pre and post treatment |
Countries
Ghana