To the Editor: We read with great interest the article by Suskind et al, entitled “Fecal Microbial Transplant via Nasogastric Tube for Active Pediatric Ulcerative Colitis” (1). Although they documented that single-dose fecal microbial transplantation via nasogastric tube was well tolerated in active pediatric ulcerative colitis, the investigators suggest that their study did not show any clinical or laboratory benefit. We would, however, like to comment on the fecal calprotectin (FC) measurement that the investigators relied upon to determine efficacy of the treatment.
FC is a validated noninvasive biomarker for inflammation in patients with inflammatory bowel disease (2). Several studies suggest that various medications such as aspirin, nonsteroidal anti-inflammatory drugs, immunosuppressant and antitumor necrosis factor medications, statins, and corticosteroids could affect FC levels (3,4). In addition, dietary food supplements such as fatty acids, zinc, vitamin D, and several probiotics can alter FC levels (5,6), and body mass indices of participants have been shown to affect FC levels (7). Finally, the timing of sample collections affects FC levels; Lasson et al (8) have suggested that concentrations of FC in stool samples collected during a single day can vary significantly. Suskind et al did not specify these potential confounding factors.
We suggest that these potential confounding factors should be conveyed to provide more reliable data and a more compelling study group. If Suskind et al can account for these contributing factors in their study population, interpretation of FC levels would be better substantiated.
1. Suskind DL, Singh N, Nielson H, et al. Fecal microbial transplant via nasogastric tube for active pediatric ulcerative colitis. J Pediatr Gastroenterol Nutr
2. Kruzliak P, Novák J, Novák M, et al. Role of calprotectin in cardiometabolic diseases. Cytokine Growth Factor Rev
3. Grip O, Janciauskiene S, Bredberg A, et al. Use of atorvastatin as an anti-inflammatory treatment in Crohn's disease. Br J Pharmacol
4. Navas-Lopez VM, Blasco-Alonso J, Girón-Fernández-Crehuet F, et al. Efficacy and safety of adalimumab in the treatment of Crohn's disease in children. Rev Esp Enferm Dig
5. Garg M, Rosella O, Lubel JS, et al. Association of circulating vitamin D concentrations with intestinal but not systemic inflammation in inflammatory bowel disease. Inflamm Bowel Dis
6. Yousefi A, Shafieyoun A, Fallahi G, et al. Probiotics on fecal calprotectin of cystic fibrosis. Turk J Pediatr
7. Cotoi OS, Dunér P, Ko N, et al. Plasma S100A8/A9 correlates with blood neutrophil counts, traditional risk factors, and cardiovascular disease in middle-aged healthy individuals. Arterioscler Thromb Vasc Biol
8. Lasson A, Stotzer PO, Öhman L, et al. The intra-individual variability of faecal calprotectin: a prospective study in patients with active ulcerative colitis. J Crohns Colitis