Effects of filarial parasite infection on type 2 diabetes

Not Applicable

• Conditions: Human filarial infection and type 2 diabetes; Infections and Infestations

• Registration Number: ISRCTN43845142
• Lead Sponsor: niversity of Buea, Faculty of Science, Department of Microbiology and Parasitology

Brief Summary

2023 Protocol article in https://doi.org/10.1371/journal.pone.0285689 (added 05/06/2023)

Detailed Description

Not available

Study Timeline

• Study Start: 2019-12-02
• Last Update Posted: 29 July 2024
• Study Completion: 2026-12-31

Recruitment & Eligibility

• Status: Ongoing
• Sex: All
• Target Recruitment: 839

Inclusion Criteria

Current inclusion criteria as of 24/01/2022:
1. Willingness to participate in the study as evidenced by signing the Informed consent form
2. Participants will be male and female between 18-60 years old
3. BMI equal to or above 30 or below 25
4. Body weight >40 kg
5. Last intake of ivermectin at least 4 months ago
6. Last intake of anti-filarial antibiotic treatment more than 12 months ago
7. Resident in an endemic area for at least 5 years
8. O. volvulus patients with microfilariae skin snip positive and PCR positive for O. volvulus
9. M. perstans patients positive for microfilariae
10. PCR endemic controls, judged by absence of microfilariae, palpable onchocercoma, PCR negative for M. perstans and O. volvulus
11. Individuals should be free of other helminth infections and possess normal eosinophil frequencies (1-4%) and IgE levels (<100 IU/ml)
12. Good general health without any clinical condition requiring long-term medication
13. Normal white blood cell counts (3.5-11.3 x 10^3/µl)

Previous inclusion criteria:
1. Willingness to participate in the study as evidenced by signing the Informed consent form
2. Participants will be male and female between 18-45 years old
3. BMI equal to or above 30 or below 25
4. Body weight >40 kg
5. Last intake of ivermectin at least 4 months ago
6. Last intake of anti-filarial antibiotic treatment more than 12 months ago
7. Resident in an endemic area for at least 5 years
8. O. volvulus patients with microfilariae skin snip positive and PCR positive for O. volvulus
9. M. perstans patients positive for microfilariae
10. PCR Endemic controls, judged by absence of microfilariae, palpable onchocercoma, PCR negative for M. perstans and O. volvulus.
11. Individuals should be free of other helminth infections and possess normal eosinophil frequencies (1-4%) and IgE levels (<100 IU/ml).
12. Good general health without any clinical condition requiring long-term medication
13. Normal white blood cell counts (4.4-11.3 x 10^3/µl)

Exclusion Criteria

1. Pregnancy (dipstick pregnancy test)
2. Lactating mothers
3. Last intake of ivermectin (IVM) less than 4 months ago
4. Intake of anti-filarial antibiotic treatment (tetracycline) less than 12 months ago
5. Evidence of tuberculosis (clinical aspects)
6. Evidence of clinical aspects of HIV infection
7. Evidence/previous diagnosis of chronic diseases (urolithiasis, liver cirrhosis, congestive heart failure, chronic lung diseases, chronic infections other than filariae, viral hepatitis)
8. Evidence of autoimmune diseases (except for diabetes) and allergies
9. Evidence of acute infection (haematuria, cough, fever). Evidence of clinically significant neurological, cardiac, pulmonary, metabolic, rheumatologic or renal disease as far as can be assessed by history of individuals, physical examination, and/or laboratory examinations
10. Childbearing potential and not willing or able to use methods to prevent pregnancy for the entire treatment duration in addition to hormonal contraception (e.g. condoms) unless surgically sterilized/ hysterectomized or any other criteria considered sufficiently reliable by the investigator.
11. Behavioural, cognitive or psychiatric disease that in the opinion of the trial clinician affects the ability of the participant to understand and cooperate with the study protocol

Added 24/01/2022:
12. Laboratory values that will lead to exclusion:
12.1. Haemoglobin <8 g/dl
12.2. Neutrophil count <500/µl*
12.3. Platelet count <100,000/µl
12.4. Creatinine >2 times upper limit of normal
12.5. AST (GOT) >2 times upper limit of normal
12.6. ALT (GPT) >2 times upper limit of normal
12.7. ?-GT >2 times upper limit of normal

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Measured using blood test at baseline and follow-up (12 and 24 months): <br>1. Fasting glucose measured by autoanalzyer<br>2. HbA1C measured by Reflotron; updated 24/01/2022: HbA1C measured by HumaStar200<br>3. Serum insulin measured by ELISA<br>4. HOMA-IR measured by the homeostasis assessment (HOMA) model (fasting insulin (mIU/ml) × fasting)

Secondary Outcome Measures

Name	Time	Method
Measured using blood test at baseline and follow-up (12 and 24 months): <br>1. Alpha-2- macroglobulin, C-peptide, TNF, IL-6, IL-10, adipokines, gut hormones, IgG subtypes, IgE, IgA (by ELISA or multiplex)<br>2. Total and differential cell counts (by automated differential cell counter)<br>3. Quantification of naïve, effector and central memory CD4+ and CD8+ T cells, regulatory T cells (Tregs), NK cells, dendritic cells (DC) and B cells in whole blood, cytokine producing T cells (by flow cytometry)<br>4. Lipid profile (total, HDL and LDL cholesterol, triglycerides – by autoanalyzer and Friedewald equation for LDL); AST, ALT, ALP, GGT, serum creatinine, urea, urine albumin, (by autoanalyzer)<br>5. Body weight, BMI, adipose tissue and muscle ratio (by weight scale body fat analyzer)<br>6. Blood pressure (blood pressure measurement device)<br>7. Waist and hip circumference (measuring tape)<br>8. Measured at baseline only: Questionnaire on medical history, dietary and physical behavior