Borghini, Porpora, Casale, Marino, Palmieri, Greco, Donato, Picarelli 2020 — IBS-like disorders in endometriosis: prevalence of nickel sensitivity and effects of a low-nickel diet
This Nutrients open-label pilot study from the Sapienza University Rome consortium (Translational and Precision Medicine + Gynecology, Obstetrics, and Urology) is the foundational link between nickel sensitivity and endometriosis. The hypothesis: gynecological and intestinal symptoms in endometriosis may depend on nickel allergic contact mucositis (Ni ACM), and a 3-month low-Ni diet should improve both intestinal and gynecological endpoints. The findings are remarkable: 90.3 percent of endometriosis patients with GI symptoms have positive Ni omPT (nickel oral mucosa patch test), and the 3-month low-Ni diet significantly improves all 15 GI symptoms, all 7 extra-intestinal symptoms, and gynecological symptoms (dysmenorrhea, dyspareunia, pelvic pain). The paper proposes nickel as a metalloestrogen contributing to endometriosis-tissue proliferation, providing a mechanistic frame beyond the GI symptom relief.
Key numbers
| Measure | Result |
|---|---|
| Endometriosis patients with GI symptoms; Ni ACM prevalence | 90.3 percent positive Ni omPT |
| Low-Ni diet improvement: GI symptoms | All 15 symptoms significantly improved |
| Low-Ni diet improvement: extra-intestinal symptoms | All 7 symptoms significantly improved |
| Low-Ni diet improvement: gynecological symptoms | Dysmenorrhea, dyspareunia, pelvic pain all significantly improved |
| Diet duration | 3 months |
Methods (brief)
Open-label pilot study at Sapienza University Rome. Inclusion: endometriosis with IBS-like or extra-intestinal symptoms. Diagnostic: nickel-oral-mucosa patch test (Ni omPT) to detect allergic contact mucositis. Intervention: 3-month low-Ni diet. Outcomes: standardized GI, extra-intestinal, and gynecological symptom scales.
Implications
- Certification: Establishes a direct clinical link between dietary nickel and endometriosis symptoms. The metalloestrogen framework expands the HMTc Ni-threshold rationale to include estrogen-receptor-binding endpoints beyond the EFSA reproductive/developmental TDI. Vulnerable-population scoping should include endometriosis patients.
- Microbiome / mucosal immunology: Ni ACM as a distinct entity from contact dermatitis — same type IV hypersensitivity machinery, different anatomical site. TLR4-dependent innate immunity also implicated in companion literature.
- Courses: Standard reference for the nickel-endometriosis link.