If the practitioner highly suspects IBS based on gastrointestinal complaints that meet Rome IV criteria (Table 37.1), and the patient exhibits no alarm signs as listed in Table 37.2, specificity for IBS is high, the diagnostic yield of further testing is generally low, and no further testing is required. Functional constipation should be differentiated from IBS-C based on a careful history and physical examination and if present, should be treated appropriately. Similarly, excessive fructose and sorbitol intake may mimic IBS-D. Unnecessary testing performed to obtain negative results increase the fear that a diagnosis is being missed and therefore should be avoided [76]. Screening for giardia should be considered in children from endemic areas [77]. It is unclear whether the prevalence of celiac disease is higher in children with IBS; a study from Italy reported a prevalence of 4 % in children with IBS compared to 1 % in the general population, whereas other studies show no increased risk [78]. There are data however, suggesting that screening for celiac disease in patients presenting with IBS symptoms may be cost effective [79, 80]. A differential diagnosis for conditions that may present similarly to IBS is provided in Table 37.3. Alarm signs may not differentiate organic disease from functional disorders, but evidence suggests that the greater the number of alarm signs present, the higher the likelihood of organic disease [81–84]. The presence of hematochezia, anemia, and weight loss in the same patient was shown to be highly predictive of Crohn’s disease [81]. If any red flags are raised, initial laboratory tests to consider that are focused, relatively inexpensive, and readily available include a complete blood count, erythrocyte sedimentation rate, C-reactive protein, serum aminotransferases and albumin, urinalysis, and celiac serologies. Fecal calprotectin is being frequently utilized as a noninvasive screen for intestinal mucosal inflammation and may be superior to C-reactive protein [85]. Normal fecal calprotectin levels make inflammatory bowel disease unlikely [86]. The need for other diagnostic testing such as abdominal imaging, breath tests, and endoscopy will depend on the clinical judgment of the practitioner.

There are many approaches to the treatment of IBS involving medications, dietary manipulations, and behavioral and physical therapies. An effective treatment plan is often multifaceted and should be individually tailored and symptom directed. It must be noted that data in the pediatric literature to support the evidence-based use of any particular treatment strategy for IBS are sparse. Most therapeutic strategies are empiric and/or are extrapolated from adult studies or from studies of recurrent abdominal pain rather than irritable bowel syndrome specifically as defined by Rome criteria.

The cornerstone of successful treatment of IBS is an effective physician–patient–family relationship based on validation of pain complaints, education, and ongoing support and reassurance for the patient and family members. Realistic goals of therapy are not necessarily to eliminate symptoms, but rather to optimize patient function, quality of life, school attendance, and extracurricular participation through a biopsychosocial approach. These goals may be achieved by alleviating symptoms using appropriately selected pharmacologic and non-pharmacologic approaches, while at the same time identifying and addressing psychological comorbidities and social factors that contribute to illness behavior. In order to set realistic expectations, goals of treatment should be made clear with the patient and family from the start. Pharmaceutical and non-pharmaceutical approaches for the treatment of IBS are shown in Table 37.4.

Irritable bowel syndrome (IBS) is a commonly encountered pediatric functional gastrointestinal disorder with varying clinical presentations. Multiple mechanisms likely contribute to its development and may include visceral hypersensitivity, altered gastrointestinal microbiota, mucosal immune activation, psychiatric disorders and cerebral activation, and altered gastrointestinal motility. The recently refined pediatric Rome (IV) criteria are more inclusive than adult criteria with respect to duration of symptoms and aid in diagnosis while avoiding exhaustive, low-yield medical testing. Although a myriad of therapeutic options are available for the treatment of IBS including medications, dietary manipulations, and behavioral and physical therapies, convincing evidence-based pediatric data to support any particular treatment modality is sparse. An effective management strategy is often multifaceted and should be individually tailored and symptom directed. Previous studies have demonstrated a particularly high placebo rate for the treatment of IBS [184], suggesting that with a strong physician–patient–family relationship, patients will improve regardless of the treatment approach. Future research in IBS will continue to focus on the pathophysiology of this disorder and on the discovery of more targeted therapies. Lastly, pediatric trials investigating the safety and effectiveness of therapies approved in adult IBS are warranted.