Cow’s Milk-Related Symptom Score (CoMiSS): From Bristol to Brussels Stool Scale

Objectives: The Cow’s Milk-related Symptom Score (CoMISS) is an awareness tool for evaluating cow’s milk-related symptoms in otherwise healthy infants <1 year of age. This study assessed whether replacing the Bristol Stool Form Scale (BSFS) with the Brussels Infants and Toddlers Stool Scale (BITSS) in non-toilet-trained infants would modify the overall CoMiSS and change the clinical approach regarding potential cow’s milk allergy. Methods: Non-toilet-trained infants aged <13 months were assessed by CoMiSS using the 7 images from the BSFS (CoMiSS-BSFS) compared to the 4 images of stools from BITSS (CoMiSS-BITSS). The Wilcoxon signed-rank test and Pearson correlation coefficient were calculated. A post hoc analysis using identical tests was performed in subsets of CoMiSS-BSFS scores ≥10, ≥12, ≤5, and ≥6. Results: Eight hundred forty-four pairwise scores were collected. Applying the Wilcoxon test over the complete dataset, the difference between CoMiSS-BSFS and CoMiSS-BITSS was statistically significant (P < 0.001). However, there was no significant difference in the subsets with CoMiSS-BSFS ≥10, ≥12, and ≥6 (P = 0.84, P = 0.48, and P = 0.81, respectively). The significant difference remained restricted to the group with CoMiSS-BSFS ≤5, considered at low risk for CM-related symptoms (P < 0.001). Conclusion: Replacing BSFS with BITSS does not change the cutoff for awareness of possible CM-related symptoms and will not impact the use of CoMiSS in clinical practice. Changes in CoMiSS remained limited to the subgroup with a low risk for CM-related symptoms.