Assessment and Treatment of Loiasis With Positive Microfilaremia

NCT06194149 | Unknown

• 1 other identifier: 49RC23_0402
• Study Type: observational
• Target: 200
• Locations: 0 countries
• Sites: N/A

Brief Summary

Loiasis is a vector-borne filariasis endemic in the forested areas in Central Africa whose incidence and morbi-mortality are poorly understood. Estimated prevalence is around 10 millions cases for a population around 30 million people. Considered to be a benign pathology, it has recently been associated with excess mortality, mainly in cases with major microfilaremia (\> 8000 mf/ml). Transmission is related to a mostly diurnal vector from the Chrysops genus. Adult worms are located in skin and subcutaneous tissues of infected patients. Females worms produce microfilariae which join bloodstream. Infected patients are mainly asymptomatic. Nevertheless, adult worms migration can lead to transient oedema (" œdème de Calabar ") ; adult worm can also be observed during subcunjonctival migration. Hypereosinophilia is also frequently encountered. Microfilariae presence in the bloodstream is asymptomatic, even in individuals with major microfilaremia. Treatment differs according to the initial microfilaremia. There are three drugs available : diethylcarbamazine (DEC) ; albendazole (ALB) and ivermectin (IVM) each with different macrofilaricidal and microfiliaricidal activities. Several treatment guidelines based on the initial microfilaremia and drug activities have been proposed, on the basis of limited data. DEC is suggested for patients with microfilaremia \< 2000 mf/ml. Regarding patients with microfilaremia between 2000 and 8000 mf/ml, initial treatment with IVM followed by DEC is suggested. Regarding patients with microfilaremia between 8000 mf/ml and 30000 mf/ml, initial treatment with IVM or ALB followed by DEC is suggested. Regarding patients with microfilaremia \> 30000 mf/ml, initial treatment with ALB or apheresis is suggested to reduce blood microfilaremia, followed by DEC. All these guidelines are associated with major adverse events, mainly life-threatening encephalopathies. These adverse events are mostly encountered in patients with major blood microfilaremia. The objective is to describe clinical characteristics, the management and clinical and biological evolution of patients with loiasis and positive blood microfilaremia.

Conditions

Loiasis With Positive Blood Microfilaremia

Keywords

Loiasis; Microfilariae; epidemiology; treatment; complication

Outcome Measures

Primary Outcomes (5)

• Description of clinical and biological evolution of treated patients with loiasis and positive blood microfilaremia

  Vital status

  At six months after treatment ; one year after treatment

• Description of clinical and biological evolution of treated patients with loiasis and positive blood microfilaremia

  Reason of death for deceased patients / Clinical assessment

  At six months after treatment ; one year after treatment

• Description of clinical and biological evolution of treated patients with loiasis and positive blood microfilaremia

  percentage of patients with symptoms related to loiasis/ Biological assessment

  At six months after treatment ; one year after treatment

• Description of clinical and biological evolution of treated patients with loiasis and positive blood microfilaremia

  percentage of patients with persistent positive microfilaremia / median microfilaremia

  At six months after treatment ; one year after treatment

• Description of clinical and biological evolution of treated patients with loiasis and positive blood microfilaremia

  percentage of patients with hypereosinophilia \> 0,5 G/l ; median eosinophilia

  At six months after treatment ; one year after treatment

Secondary Outcomes (1)

• Description of adverse events after treatment in patients with loiasis and positive blood microfilaremia

  one year after treatment

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Our cohort study is composed of patients diagnosed with loiasis with at least one positive blood microfilaremia \> 0mf/ml. Patients are screened using data avalaible in the parasitology laboratories in our partcipating centers. Data are collected anonimously.

You may qualify if:

• Patient managed in one of the participating centers between the 01/01/2000 and the 12/31/2022
• Loiasis diagnosis with at least one positive blood microfilaremia \> 0mf/ml
• Patient treated against loiasis
• At least one clinical and/or biological assessment after the first treatment dose

Sponsors & Collaborators

• University Hospital, Angers: lead

Related Publications (6)

• Chesnais CB, Takougang I, Paguele M, Pion SD, Boussinesq M. Excess mortality associated with loiasis: a retrospective population-based cohort study. Lancet Infect Dis. 2017 Jan;17(1):108-116. doi: 10.1016/S1473-3099(16)30405-4. Epub 2016 Oct 21.

  PMID: 27777031 BACKGROUND

• Boussinesq M. Loiasis: new epidemiologic insights and proposed treatment strategy. J Travel Med. 2012 May-Jun;19(3):140-3. doi: 10.1111/j.1708-8305.2012.00605.x. No abstract available.

  PMID: 22530819 BACKGROUND

• Veletzky L, Eberhardt KA, Hergeth J, Stelzl DR, Zoleko Manego R, Mombo-Ngoma G, Kreuzmair R, Burger G, Adegnika AA, Agnandji ST, Matsiegui PB, Boussinesq M, Mordmuller B, Ramharter M. Distinct loiasis infection states and associated clinical and hematological manifestations in patients from Gabon. PLoS Negl Trop Dis. 2022 Sep 19;16(9):e0010793. doi: 10.1371/journal.pntd.0010793. eCollection 2022 Sep.

  PMID: 36121900 BACKGROUND

• Bouchaud O, Matheron S, Loarec A, Dupouy Camet J, Bouree P, Godineau N, Poilane I, Cailhol J, Caumes E. Imported loiasis in France: a retrospective analysis of 167 cases with comparison between sub-Saharan and non sub-Saharan African patients. BMC Infect Dis. 2020 Jan 20;20(1):63. doi: 10.1186/s12879-019-4740-6.

  PMID: 31959110 BACKGROUND

• Gardon J, Gardon-Wendel N, Demanga-Ngangue, Kamgno J, Chippaux JP, Boussinesq M. Serious reactions after mass treatment of onchocerciasis with ivermectin in an area endemic for Loa loa infection. Lancet. 1997 Jul 5;350(9070):18-22. doi: 10.1016/S0140-6736(96)11094-1.

  PMID: 9217715 BACKGROUND

• Garcia A, Abel L, Cot M, Ranque S, Richard P, Boussinesq M, Chippaux JP. Longitudinal survey of Loa loa filariasis in southern Cameroon: long-term stability and factors influencing individual microfilarial status. Am J Trop Med Hyg. 1995 Apr;52(4):370-5. doi: 10.4269/ajtmh.1995.52.370.

  PMID: 7741181 BACKGROUND

MeSH Terms

Conditions

Loiasis

Condition Hierarchy (Ancestors)

Filariasis; Spirurida Infections; Secernentea Infections; Nematode Infections; Helminthiasis; Parasitic Diseases; Infections

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 8, 2023
• First Posted: January 8, 2024
• Study Start: February 1, 2024
• Primary Completion: February 15, 2024
• Study Completion: June 30, 2024
• Last Updated: January 8, 2024

Record last verified: 2023-12