Higher incidence of zinc and nickel hypersensitivity in patients with irritable bowel syndrome
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Metals
Metals
OverviewHeavy metals play a significant and multifaceted role in the pathogenicity of microbial species. Their involvement can be viewed from two primary perspectives: the toxicity of heavy metals to microbes and the exploitation of heavy metals by microbial pathogens to establish infections and evade the host immune response. Understanding these aspects is critical for both […]
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Karen Pendergrass
What was studied?
This study investigated the incidence of hypersensitivity to dental metals—specifically zinc, nickel, gold, and palladium—in patients with Irritable Bowel Syndrome (IBS). The study aimed to assess whether hypersensitivity to these metals, which are commonly used in dental prostheses, could be linked to immune activation in IBS patients. The focus was on understanding how metal-induced hypersensitivity may contribute to the low-grade mucosal inflammation observed in a subset of IBS patients.
Who was studied?
The study recruited 147 Japanese patients diagnosed with IBS according to the Rome IV diagnostic criteria and 22 healthy controls (HC). The IBS patients were classified into four subtypes:
IBS-D (diarrhea-predominant IBS): 59 patients (40.1%)
IBS-C (constipation-predominant IBS): 9 patients (6.1%)
IBS-M (IBS with mixed bowel habits): 66 patients (44.9%)
IBS-U (unspecified IBS): 13 patients (8.8%)
The subjects underwent the drug-induced lymphocyte stimulation test (DLST) to detect hypersensitivity to the metals examined quantitatively.
What were the most important findings?
Increased hypersensitivity in IBS patients: 56.5% of IBS patients demonstrated hypersensitivity to at least one metal species, compared to only 31.8% of healthy controls.
Higher sensitivity to zinc and nickel: A significant portion of IBS patients was hypersensitive to zinc (36.4%) and nickel (39.6%), whereas none of the healthy controls exhibited hypersensitivity to zinc, and only 21.1% showed sensitivity to nickel.
Severe sensitivity: IBS patients had a significantly higher stimulation index (SI) for both zinc and nickel compared to healthy controls.
No significant difference across IBS subtypes: There was no significant difference in metal hypersensitivity rates or SI values across different IBS subtypes (IBS-D, IBS-C, IBS-M, IBS-U).
What are the greatest implications of this study?
The study highlights a potential immune-mediated link between hypersensitivity to dental metals, particularly zinc and nickel, and the pathogenesis of IBS in a subset of patients. The findings suggest that metal hypersensitivity may contribute to the mucosal inflammation observed in IBS patients. This pilot study underscores the importance of considering hypersensitivity reactions as part of IBS management, potentially leading to personalized treatment approaches, such as dietary modifications like a low-nickel diet, or avoiding exposure to specific metals in dental materials.
Zinc
Zinc is an essential trace element vital for cellular functions and microbiome health. It influences immune regulation, pathogen virulence, and disease progression in conditions like IBS and breast cancer. Pathogens exploit zinc for survival, while therapeutic zinc chelation can suppress virulence, rebalance the microbiome, and offer potential treatments for inflammatory and degenerative diseases.
Nickel
Bacteria regulate transition metal levels through complex mechanisms to ensure survival and adaptability, influencing both their physiology and the development of antimicrobial strategies.
Irritable Bowel Syndrome (IBS)
Irritable Bowel Syndrome (IBS) is a common gastrointestinal disorder characterized by symptoms such as abdominal pain, bloating, and altered bowel habits. Recent research has focused on the gut microbiota's role in IBS, aiming to identify specific microbial signatures associated with the condition.
Nickel
Bacteria regulate transition metal levels through complex mechanisms to ensure survival and adaptability, influencing both their physiology and the development of antimicrobial strategies.
Nickel
Bacteria regulate transition metal levels through complex mechanisms to ensure survival and adaptability, influencing both their physiology and the development of antimicrobial strategies.
Low‑Nickel Diet (LNiD)
A low-nickel diet (LNiD) is a therapeutic dietary intervention that eliminates high-nickel foods, primarily plant-based sources such as legumes, nuts, whole grains, and cocoa, to reduce systemic nickel exposure. It is clinically validated for managing systemic nickel allergy syndrome (SNAS) and nickel-induced eczema. Its relevance is well-established in microbiome modulation, with studies demonstrating clinical benefits in conditions such as endometriosis, fibromyalgia, irritable bowel syndrome, and GERD.