Roles of Lactose and Fructose Malabsorption and Dietary Outcomes in Children Presenting with Chronic Abdominal Pain

Abstract

Intolerance to lactose or fructose is frequently diagnosed in children with chronic abdominal pain (CAP). However, the causal relationship remains a matter of discussion. A cohort of 253 patients, aged 7–12 years, presenting with unexplained CAP received standardized diagnostics. Additional diagnostic tests were performed based on their medical history and physical and laboratory investigations. Fructose and lactose hydrogen breath tests (H2BT) as well as empiric diagnostic elimination diets were performed in 135 patients reporting abdominal pain related to the consumption of lactose or fructose to evaluate carbohydrate intolerance as a potential cause of CAP. Carbohydrate malabsorption by H2BT was found in 55 (41%) out of 135 patients. An abnormal increase in H2BT was revealed in 30% (35/118) of patients after fructose consumption and in 18% (20/114) of patients after lactose administration. Forty-six percent (25/54) reported pain relief during a diagnostic elimination diet. In total, 17 patients had lactose malabsorption, 29 fructose malabsorption, and nine combined carbohydrate malabsorption. Carbohydrate intolerance as a cause of CAP was diagnosed at follow-up in only 18% (10/55) of patients with malabsorption after the elimination of the respective carbohydrate. Thus, carbohydrate malabsorption appears to be an incidental finding in children with functional abdominal pain disorders, rather than its cause. Therefore, testing of carbohydrate intolerance should only be considered in children with a strong clinical suspicion and with the goal to prevent long-term unnecessary dietary restrictions in children suffering from CAP.

Clinical Utility of LCT Genotyping in Children with Suspected Functional Gastrointestinal Disorder

“…Our results show that a diagnosis of lactose malabsorption (defined based on HBT results) was established in about one third (36.3%) of children with recurrent abdominal pain due to suspected functional disorder. This frequency is similar to that reported in other series in children with chronic abdominal pain [ 31 ], and in line with that observed in a healthy population in Spain [ 32 ]. Moreover, the frequency of malabsorption increased with age, from 8% in children ≤5 years to 49.5% in children aged >12 years ( p = 0.001).…”

“…Moreover, the frequency of malabsorption increased with age, from 8% in children ≤5 years to 49.5% in children aged >12 years ( p = 0.001). Lactose malabsorption therefore appears not to play a major role in FGID in younger children, in agreement with previous studies indicating that carbohydrate malabsorption may be an incidental finding in children with FGID, rather than its cause [ 31 ]. When evaluating FGID in infants and children, we should screen for celiac disease (CD) as its prevalence among children with irritable bowel syndrome is higher than in general pediatric population [ 33 ].…”

Update on the Role of Allergy in Pediatric Functional Abdominal Pain Disorders: A Clinical Perspective

“…For example, lactose malabsorption is a well-recognized food intolerance. In most studies, lactose restriction does not result in clinical improvement even in patients with demonstrated malabsorption [ 9 , 10 , 11 , 12 ]. It is now recognized that this malabsorption is associated with increased mucosal mast cells and increased colonic eosinophils and lymphocytes, which may persist after lactose elimination [ 13 , 14 , 15 , 16 ].…”

Valid Assessment of Carbohydrate Intolerance and the Need for a Distinction to Carbohydrate Malabsorption. Comment on “Roles of Lactose and Fructose Malabsorption and Dietary Outcomes in Children Presenting with Chronic Abdominal Pain.” Nutrients 2019, 11, 3063

“…We have read with interest the recent paper by Posovszky and Roesler et al [ 1 ] that reports, based on the doctoral thesis by Dr. Roesler [ 2 ], on the possible role of carbohydrate malabsorption and dietary outcomes in children with chronic abdominal pain (CAP). A better understanding of the mechanisms underlying functional abdominal pain may improve therapeutic options beyond general dietary advices.…”