Irritable Bowel Syndrome-Like Disorders in Endometriosis: Prevalence of Nickel Sensitivity and Effects of a Low-Nickel Diet. An Open-Label Pilot Study

Nutrients. 2020 Jan 28;12(2):341. doi: 10.3390/nu12020341.


Alimentary nickel (Ni) may result in allergic contact mucositis (ACM), whose prevalence is >30% and may present with IBS-like and extra-intestinal symptoms. These symptoms are also frequent in endometriosis, and Ni allergic contact dermatitis has already been observed in endometriosis. Therefore, intestinal and extra-intestinal symptoms in endometriosis may depend on a Ni ACM, and a low-Ni diet could improve symptoms. We studied the prevalence of Ni ACM in endometriosis and focused on the effects of a low-Ni diet on gastrointestinal, extra-intestinal, and gynecological symptoms. We recruited 84 women with endometriosis, symptomatic for gastrointestinal disorders. Thirty-one out of 84 patients completed the study. They underwent Ni oral mucosa patch test (omPT), questionnaire for intestinal/extra-intestinal/gynecological symptoms, and a low-Ni diet. Clinical evaluation was performed at baseline (T0) and after three months (T1). Twenty-eight out 31 (90.3%) patients showed Ni omPT positive results, with Ni ACM diagnosis, whereas three out of 31 (9.7%) patients showed negative Ni omPT. After three months of low-Ni diet, all gastrointestinal, extra-intestinal and gynecological symptoms showed a statistically significant reduction. Ni ACM has a high prevalence in endometriosis and a low-Ni diet may be recommended in this condition to reduce gastrointestinal, extra-intestinal and gynecological symptoms.

Keywords: Nickel allergy; allergic contact mucositis; endometriosis; irritable bowel syndrome (IBS); low-nickel diet.

MeSH terms

  • Adult
  • Diet*
  • Endometriosis / complications*
  • Female
  • Humans
  • Irritable Bowel Syndrome / chemically induced
  • Irritable Bowel Syndrome / complications*
  • Irritable Bowel Syndrome / immunology
  • Middle Aged
  • Mucositis / chemically induced
  • Nickel / immunology*
  • Pilot Projects
  • Young Adult


  • Nickel