Patients with inflammatory bowel disease (IBD) are at increased risk for zinc (Zn) deficiency due to frequent diarrhea and disrupted absorption.1 Similarly, acute diarrheal illness decreases serum Zn levels.2 Clostridium difficile infection (CDI) is a frequent cause of worsening diarrhea in the IBD population, with previous studies demonstrating a 2-fold increased risk of CDI in IBD patients compared to non-IBD patients.3 This raises concern for combined-cause Zn wasting in IBD patients with CDI. We aim to compare serum Zn levels following multiple episodes of CDI between patients with and without a history of IBD. We hypothesize that IBD patients will have lower Zn levels and greater rate of deficiency than patients without IBD (non-IBD).Methods:
We retrospectively reviewed patients seen at our center for recurrent C. difficile infection (rCDI) from September 2013 to April 2016. We included only those individuals with ≥2 CDIs and a recorded Zn value within 6 months of the second infection. CDI was defined by positive C. difficile stool test or colonoscopic visualization of pseudomembranous colitis, and rCDIs were defined as occurring ≥14 days following previous CDI treated with antibiotics. Patients receiving Zn supplementation or fecal microbiota transplant (FMT) prior to the recorded Zn value were excluded.Results:
Two hundred eight patients were seen for rCDI; 102 met criteria and were categorized as having a history of IBD (n = 22) or no history of IBD (non-IBD) (n = 80). This included 70 women and 32 men, with a mean age of 62. IBD patients had a mean serum Zn of 0.64 ± 0.13 mcg/mL (mean ± 1 SD) and non-IBD patients had a mean Zn of 0.69 ± 0.14 mcg/mL (P = 0.028). A greater proportion of IBD patients (63.6%) were Zn deficient (range 0.66–1.10 mcg/mL) compared to non-IBD patients (33.8%) (P = 0.011). CDI episode frequency between the groups in the 6 months preceding the Zn value was similar in the IBD (2.55) and non-IBD (2.65) patients (P = 0.59).Conclusions:
In the setting of multiple recent CDI, IBD patients had lower zinc levels when compared with non-IBD patients. Due to the retrospective nature of the data collection, we cannot determine causality. Nevertheless, it is likely that IBD patients are at increased risk for zinc deficiency due to lower baseline serum zinc values prior to initial CDI. Greater volume diarrhea because of a combination of IBD and CDI may also be a contributing factor. Given the increased risk of CDI in IBD patients, more study of zinc deficiency within this subset of IBD patients is warranted.