Association of Giardia Duodenalis Infection with Serum Vitamin a Status in Children: A Comparative Case Control Study

Background: Giardia duodenalis remain as common intestinal protozoan parasitic infection all over the world. Therefore, current study was purposed to explore the association of serum vitamin A concentrations with infection of Giardia duodenalis in children.Methods: This comparative case control study was done on 50 children aged 5 to 10 years, and was conducted on 25 G. duodenalis infected children and 25 apparently healthy children as control in Al-Muthanna and Al-Diwaniyah (Iraq). The stool samples were assessed microscopically for incidence of G. duodenalis cysts and trophozoites. Blood samples were collected and serum was separated to measure vitamin A concentrations.Results: The serum vitamin A level in Giardia-infected group was less (20.48 ± 9.91 µg/dL) compared to control (31.48 ± 6.19 µg/dL) group. The variation between groups was notably significant (p < 0.001). The median vitamin A concentration was (16 µg/dL) in infected children and (32 µg/dL) in controls. Serum vitamin A concentrations ranged from (11 to 45µg/dL) in infected group and from (20 to 44µg/dL) in control group. Sixteen infected children (64.0%) had vitamin A concentrations of ( ≤20 µg/dL), compared with only two children (8.0%) in the control group. The difference in frequency of low vitamin A concentrations between two groups was remarkable significant (p < 0.001).Conclusion: Children infected with G. duodenalis had significantly lower serum vitamin A level than children in control group. The high proportion of infected children with low vitamin A concentrations supports a significant association between giardiasis and impaired vitamin A status. This relationship may be related to intestinal dysfunction, malabsorption, reduced dietary intake, or infection-associated alterations in vitamin A metabolism.