Evidence map›Paper›PMID 41296809›Full record

ArticlePLoS neglected tropical diseases2025

Investigating HLA haplotypes as a potential risk factor for nodding syndrome: A case-control study in the Mahenge area, Tanzania.

Amber Hadermann, Dan Bhwana, Athanas D Mhina, Luís-Jorge Amaral, Joseph N Siewe Fodjo, Marie-Paule Emonds, Sarah Weckhuysen, Bruno P Mmbando, Robert Colebunders

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Article in PLoS neglected tropical diseases, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

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0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Nodding Syndrome: Shifting the Focus from Cause to Treatment.The American journal of tropical medicine and hygiene · 2026
    Review
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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Amber HadermannGlobal Health Institute, University of Antwerp, Antwerp, Belgium.ORCID 0000-0003-1207-5811
Dan BhwanaNational Institute for Medical Research, Tanga Research, Tanga, Tanzania.
Athanas D MhinaNational Institute for Medical Research, Tanga Research, Tanga, Tanzania.
Luís-Jorge AmaralGlobal Health Institute, University of Antwerp, Antwerp, Belgium.
Joseph N Siewe FodjoGlobal Health Institute, University of Antwerp, Antwerp, Belgium.
Marie-Paule EmondsHistocompatibility and Immunogenetics Laboratory, Belgian Red Cross-Flanders, Mechelen, Belgium.
Sarah WeckhuysenDepartment of Neurology, University Hospital Antwerp, Belgium.
Bruno P MmbandoNational Institute for Medical Research, Tanga Research, Tanga, Tanzania.
Robert ColebundersGlobal Health Institute, University of Antwerp, Antwerp, Belgium.

Funding

Flemish University development cooperationResearch Foundation Flanders (FWO)
6 · The paper itself

Abstract

backgroundNodding syndrome (NS) is a disabling childhood-onset epilepsy occurring in onchocerciasis-endemic regions. High Onchocerca volvulus microfilarial loads in childhood are a key risk factor, but not all heavily infected individuals develop NS, suggesting a possible role for host genetic susceptibility. Human leukocyte antigen (HLA) haplotypes have been implicated in susceptibility to various infectious and autoimmune diseases, including onchocerciasis. We investigated potential associations between HLA haplotypes and onchocerciasis-associated epilepsy (OAE), including NS, in Tanzania.

methodsA case-control study was conducted in an onchocerciasis-endemic area in the Mahenge area, Tanzania, including 98 persons with epilepsy and 112 controls. DNA was extracted from dry blood spots and HLA sequence-based typing was performed by Histogenetics (Ossining, USA). A total of 11 HLA loci (HLA-A, -B, -C, -DRB1, -DRB3, -DRB4, -DRB5, -DQA1, -DQB1, -DPA1, and -DPB1) were exon sequenced. The HLA-typed dataset was analysed using pyHLA, including Bonferroni as multi-test adjustment, to test for associations with O. volvulus anti-Ov16 seropositivity, epilepsy, OAE and NS.

resultsAnti-Ov16 seropositivity was significantly higher in cases than controls (76.5% vs 58.9%; p = 0.01). No HLA alleles were significantly associated with epilepsy, OAE, NS, or anti-Ov16 seropositivity after correction. Before adjustment, HLA-C07:01 appeared to be a risk factor for epilepsy, HLA-DQB106:02 was associated with OAE, HLA-B35:01 with NS, and HLA-C08:02 and DRB1*03:01 with anti-Ov16 seropositivity. Post-hoc power analysis indicated that substantially larger sample sizes would be required to confirm these associations.

conclusionsThis study did not identify statistically significant HLA associations with epilepsy, OAE, NS, or O. volvulus exposure. However, several alleles-particularly HLA-B*35:01, also reported in a previous South Sudanese study-emerged as potential candidates for further investigation. Larger, multi-country studies with sufficient power are needed to clarify whether host genetic factors contribute to susceptibility to OAE and NS. Strengthening onchocerciasis elimination programmes remains essential, as NS is a preventable disease.

Indexed as

Genetic Predisposition to DiseaseHaplotypesHLA AntigensNodding SyndromeOnchocerciasisAdolescentAdultCase-Control StudiesChildChild, PreschoolFemaleHumansMaleOnchocerca volvulusRisk FactorsTanzaniaHLA Antigens

Identifiers

PMID41296809
PMCPMC12680330

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