Pathological Manifestations of Gluten-Related Neuro-Psychiatric Disorders and the Impact of Gluten-Free Diet in a Pediatric Age Group: A Systematic Review

Gluten, as a term, causes unease among a vast majority of the population. The reason is the body's inability to process gluten, causing various pathological manifestations. While celiac disease is predominantly a gastrointestinal disease, it also has various extra-intestinal manifestations. Many children receive diagnoses of idiopathic neuropsychiatric symptoms such as epilepsy, attention-deficit hyperactivity disorder (ADHD), restless leg syndrome (RLS), and peripheral neuropathy without ever finding the root cause. A majority of these cases may be associated with celiac disease if only their antibody titers and other appropriate investigations were conducted. The treatment of these manifestations may be eliminated or at least controllable with dietary modification to a gluten-free diet (GFD). In this paper, we will discuss the pathology of celiac disease and the impact of GFD on the neuropsychiatric aspects of this disease, which is of higher prevalence in the pediatric population. A comprehensive literature search was conducted in prominent databases, namely PubMed and Google Scholar, to include studies that provided individual-level data on the neuropathological manifestations and the impact of a GFD on extra-intestinal manifestations of celiac disease. The research protocol was registered in the PROSPERO database (International Prospective Register of Systematic Reviews) with the registration ID: CRD42023415100. Based on the inclusion and exclusion criteria, we included prospective studies, observational studies, and case reports on pediatric patients with biopsy-proven celiac disease, serologically positive celiac disease, celiac disease with neuropsychiatric manifestations, and studies reporting the impact of GFD. After a rigorous quality assessment to remove the risk of bias, we finally included 20 studies to be discussed. In 6 (30%) studies, patients with neuropsychiatric manifestations had positive serology findings and a relatively higher grade of biopsy results. Seven studies discussed the positive impact of GFD. Five of these seven studies reported statistically significant results (p ≤ 0.001). Our study suggests that gluten plays a role in the severity of neuropsychiatric manifestations of celiac disease. Considering the results of our study, we can see that GFD does impact the prognosis of the disease. Neuropsychiatric findings without gastrointestinal manifestations are more common in the pediatric age group. We have clear evidence that several neurological conditions (neuropathy, ADHD, epilepsy, and RLS) have not only a significant association with gluten but can also potentially benefit from GFD. Thus, screening, with a combination of serological, biopsy, and imaging techniques, must be adapted into the guidelines for early detection and induction of GFD. Furthermore, studies should aim at introducing GFD in the pediatric population as a mode of primary prevention. In conclusion, our review underscores the importance of gluten while dealing with idiopathic neurological conditions in children and hopes to shed light on this commonly misdiagnosed and easily manageable disease.