Relation between clinical symptoms and experimental visceral hypersensitivity in pediatric patients with functional abdominal pain

Pain Catastrophizing Moderates the Relationship Between Pain Sensitivity and Clinical Pain in Adolescents With Functional Abdominal Pain

Pain catastrophizing has been linked to amplified pain sensitivity assessed using quantitative sensory testing (QST) in adults; pediatric data are limited, particularly in youth with functional abdominal pain (FAP). With increasing use of QST to evaluate somatosensory function and predict pain outcomes, we examined the associations between QST and clinical pain in adolescents with FAP and tested the moderating effects of pain catastrophizing. Seventy-seven adolescents (mean age 16.6 years, 85.7% female, 72.7% White, 90.8% non-Hispanic) who fulfilled diagnostic criteria for FAP completed QST assessment (pressure pain threshold and tolerance, heat pain threshold, conditioned pain modulation) and measures of abdominal pain intensity, pain interference, and pain catastrophizing. Adjusting for age and sex, only higher heat pain threshold was associated with higher abdominal pain intensity (Beta per 1-standard deviation = .54, P = .026). Contrary to hypothesis, for youth with higher pain catastrophizing, higher pressure pain tolerance was associated with greater abdominal pain intensity, but associations were not significant for youth with lower catastrophizing (P = .049). Similarly, for those with higher pain catastrophizing (in contrast to lower pain catastrophizing), higher pressure pain thresholds and tolerance were associated with higher pain interference (P = .039, .004, respectively). Results highlight the need to investigate the influence of pain catastrophizing on QST. PERSPECTIVE: This study demonstrated unexpected findings of pain catastrophizing moderating the relationships between pressure pain threshold and tolerance, and clinical pain in adolescents with FAP. This raised questions regarding our understanding of psychological contributions to QST findings in pediatric populations with chronic pain.

Increased Prevalence of Sensory Processing Issues in Pediatric Gastrointestinal Patient Population

Background Sensory processing dysfunction in children has been linked to attention-deficit/hyperactivity disorder, autism, feeding disorders, and functional abdominal pain. However, little is known about sensory processing in the broader pediatric gastroenterology population. Objective To characterize frequency and type of sensory processing dysfunction seen in pediatric gastroenterology compared to a general pediatric population. Methods The Short Sensory Profile 2 was administered to the parents of children ranging 3-14 years, being seen in a pediatric gastrointestinal (GI) subspecialty clinic or general pediatric clinic. Short Sensory Profile 2 scores from age- and gender-matched groups were compared with nonparametric statistics. Results Sensory processing dysfunction was increased in children seen in the GI clinic compared to children in the general pediatric clinic. Short Sensory Profile 2 quadrant analysis revealed greatest differences in avoiding, primarily in young females of the GI population. Conclusion Children presenting to a pediatric GI clinic demonstrate greater sensory processing dysfunction compared to children in a general pediatric practice.

Effect of percutaneous electrical nerve field stimulation on mechanosensitivity, sleep, and psychological comorbidities in adolescents with functional abdominal pain disorders

BACKGROUND

Percutaneous electrical nerve field stimulation (PENFS) improves symptoms in adolescents with functional abdominal pain disorders (FAPDs). However, little is known about its impact on sleep and psychological functioning. We evaluated the effects of PENFS on resting and evoked pain and nausea, sleep and psychological functioning, and long-term outcomes.

METHODS

Patient ages 11-19 years with FAPD requiring PENFS as standard care were recruited. Evoked pain was elicited by a Water Load Symptom Provocation Task (WL-SPT) before and after four weeks of treatment. Pain, gastrointestinal symptoms, sleep, somatic symptoms, and physical and psychological functioning were assessed. Actigraphy was used to measure daily sleep-wake patterns.

KEY RESULTS

Twenty patients (14.3 ± 2.2 years old) with FAPD were enrolled. Most patients were females (70%) and white (95%). During pain evoked by WL-SPT, visual analog scale (VAS) pain intensity and nausea were lower following PENFS compared with baseline (p = 0.004 and p = 0.02, respectively). After PENFS, resting VAS pain unpleasantness (p = 0.03), abdominal pain (p < 0.0001), pain catastrophizing (p = 0.0004), somatic complaints (0.01), functional disability (p = 0.04), and anxiety (p = 0.02) exhibited significant improvements, and some were sustained long-term. Self-reported sleep improved after PENFS (p's < 0.05) as well as actigraphy-derived sleep onset latency (p = 0.03).

CONCLUSIONS AND INFERENCES

We demonstrated improvements in resting and evoked pain and nausea, sleep, disability, pain catastrophizing, somatic complaints, and anxiety after four weeks of PENFS therapy. Some effects were sustained at 6-12 months post-treatment. This suggests that PENFS is a suitable alternative to pharmacologic therapy.

Noninvasive bladder testing of adolescent females to assess visceral hypersensitivity

ABSTRACT

Excess pain after visceral provocation has been suggested as a marker for chronic pelvic pain risk in women. However, few noninvasive tests have been validated that could be performed readily on youth in early risk windows. Therefore, we evaluated the validity and reliability of a noninvasive bladder pain test in 124 healthy premenarchal females (median age 11, [interquartile range 11-12]), as previously studied in adult women. We explored whether psychosocial, sensory factors, and quantitative sensory test results were associated with provoked bladder pain and assessed the relation of bladder pain with abdominal pain history. Compared with findings in young adult females (age 21 [20-28]), results were similar except that adolescents had more pain at first sensation to void (P = 0.005) and lower maximum tolerance volume (P < 0.001). Anxiety, depression, somatic symptoms, and pain catastrophizing predicted provoked bladder pain (P's < 0.05). Bladder pain inversely correlated with pressure pain thresholds (r = -0.25, P < 0.05), but not with cold pressor pain or conditioned pain modulation effectiveness. Bladder pain was also associated with frequency of abdominal pain symptoms (r = 0.25, P = 0.039). We found strong retest reliability for bladder pain at standard levels of sensory urgency in 21 adolescents who attended repeat visits at 6 to 12 months (intraclass correlations = 0.88-0.90). Noninvasive bladder pain testing seems reproducible in adolescent females and may predict abdominal pain symptomatology. Confirmation of our findings and further investigation of the bladder test across menarche will help establish how visceral sensitivity contributes to the early trajectory of pelvic pain risk.

Validation of the Health-Related Felt Stigma and Concealment Questionnaire

OBJECTIVE

Stigma is associated with many health conditions, including chronic pain. Research on health-related stigma is limited by the lack of validated instruments that distinguish among various stigma-related constructs. We aimed to develop and validate such a measure for pediatric functional abdominal pain (FAP). Felt stigma (FS) was defined as comprising both perceived and internalized stigma. Stigma concealment (SC) was defined as efforts by stigmatized individuals to prevent others from learning of their condition.

METHODS

Using a theory-driven approach, we adapted items from existing self-report measures of stigma to construct the health-related FS and Concealment Questionnaire (FSC-Q). Patients with FAP (N = 179, ages 11-17) completed the preliminary FSC-Q and health-related measures hypothesized to be associated with stigma. Cognitive interviewing and exploratory factor analysis (EFA) informed the final version of the measure.

RESULTS

EFA identified a 2-factor model comprised of FS and SC. The FS and SC scales exhibited good internal consistency and construct validity. Consistent with study hypotheses, both factors were significantly associated with anxiety, depression, pain catastrophizing, pain threat, physical symptoms, and pain interference/disability. Higher FS was associated with higher mental healthcare utilization. The subset of participants meeting criteria for irritable bowel syndrome (IBS) reported higher FS and SC compared with those without IBS.

CONCLUSION

The FSC-Q may help advance research on health-related stigma in FAP and other chronic health conditions by allowing for assessment of distinct stigma-related constructs.

The correlation of functional pain and psychological distress: a study in Italian school students

Background

Functional Pain (not detectable organic cause) is often associated with psychological problems and, according to literature, it can lead to severe manifestations.

The purpose of the study was to investigate the correlation between functional pain and psychological disagreement, in a series of school students.

Methods

An observational questionnaire-based study was performed.

A questionnaire was given to a group of students of primary school; the following data were collected in the questionnaire: a) sex and age; b) functional pain; c) relation with relatives, teachers and schoolfellows: d) school failure.

Statistical methods: P-value of concordance test and P-value of correlation have been performed with MINITAB 15.1 software.

Results

Eight hundred nine students, 354 females, 455 males, median age 14 years, participated to the study.

Functional Pain was referred from 537/809 students (66%): 265 Females, 272 males: p = 0.155. The difference between the number of pain episodes in females vs. males was statistically significant (p = 0,511), as pain intensity vs. the number of episodes in females (p = 0.001).

The most frequent location of pain was abdomen in females, limbs in males.

Psychological disagreement was referred from 513/809 students (63%) (260 females; 253 males: p = 0,150).

Psychological disagreement was reported with parents (19); siblings (22); other relatives (18); teachers: 42, schoolfellows: 366, relatives as well as school fellows: 46.

The correlation between disagreement and functional pain in all the students included in the study was statistically significant (p < 0.001).

Conclusions

most students reported psychological disagreement and pain. The most frequent cause of disagreement was schoolfellows’ behaviour. The study shows a student’s lack of discussing of their problems with parents, teachers, peer. According to literature, confiance would be a useful treatment for avoiding psychological disagreements and functional pain.

Efficacy of adding interoceptive exposure to intensive interdisciplinary treatment for adolescents with chronic pain: a randomized controlled trial

Fear of pain plays an important role in the maintenance of chronic pain. It may be reduced through exposure therapy. This 2-arm parallel samples randomized controlled trial aimed to investigate whether interoceptive exposure (IE) therapy enhances reductions in fear of pain (primary outcome), pain (pain intensity, pain-related disability, and school absence), and emotional characteristics (anxiety and catastrophizing) when implemented as an adjunctive treatment in the context of intensive interdisciplinary pain treatment for pediatric chronic pain patients. N = 126 adolescents, aged 11 to 17 years, who were receiving standard intensive interdisciplinary pain treatment were randomly assigned to either receive additional IE (n = 64) or additional relaxation therapy (RT) (n = 62). All patients were assessed at admission, discharge, and 3 months after discharge. The data of N = 104 patients were analyzed. Significant large reductions were found in the total score and subscale scores of the Fear of Pain Questionnaire for Children in both study groups (eg, total score [range 0-60; IE/RT]: admission M = 23.5/24.9; discharge M = 16.0/19.7; P < 0.001, (Equation is included in full-text article.)= 0.27) and mainly large reductions in pain characteristics. There were no greater decreases in the IE group (P > 0.1). The exploratory analyses revealed that the patients with high fear of pain before treatment (P < 0.05, (Equation is included in full-text article.)> 0.03) and the patients with abdominal pain (P < 0.04, (Equation is included in full-text article.)> 0.25) showed greater decreases in their fear of pain (total and subscale score) in the IE group than in the RT group. In conclusion, the results suggest that IE is not particularly effective for all the pediatric chronic pain patients, but the patients with high fear of pain before treatment and with abdominal pain strongly benefit from this intervention.

A population-based study of quantitative sensory testing in adolescents with and without chronic pain

Quantitative sensory testing (QST) has been used to characterize pain sensitivity in individuals with and without pain conditions. Research remains limited in pediatric populations, hindering the ability to expand the utility of QST toward its potential application in clinical settings and clinical predictive value. The aims of this study were to examine pain sensitivity using QST in adolescents with chronic pain compared to adolescents without chronic pain and identify predictors of pain sensitivity. A population-based study conducted from 2010 to 2011 provided data on 941 adolescents, 197 were classified as having chronic pain and 744 were classified without chronic pain. Self-reported data on pain characteristics, psychological functioning, and QST responses were examined. The findings revealed lower pressure pain threshold and tolerance on the trapezius (P's = 0.03) in adolescents with chronic pain compared to adolescents without chronic pain, but no differences on heat or cold-pressor pain tasks. Female sex (P's = 0.02) and poorer psychological functioning (P's = 0.02) emerged as significant predictors of greater pain sensitivity across all pain modalities. Exploratory analyses revealed several associations between clinical pain characteristics and QST responses within the chronic pain cohort. Findings from this large pediatric sample provide comprehensive data that could serve as normative data on QST responses in adolescents with and without chronic pain. These findings lay the groundwork toward developing future QST research and study protocols in pediatric populations, taking into consideration sex and psychological distress.

Parental Protectiveness Mediates the Association between Parent-Perceived Child Self-Efficacy and Health Outcomes in Pediatric Functional Abdominal Pain Disorder

Previous studies have shown that parental protectiveness is associated with increased pain and disability in Functional Abdominal Pain Disorder (FAPD) but the role that perceived child self-efficacy may play remains unclear. One reason why parents may react protectively towards their child's pain is that they perceive their child to be unable to cope or function normally while in pain (perceived low self-efficacy). This study sought to examine (a) the association between parent-perceived child pain self-efficacy and child health outcomes (symptom severity and disability); and (b) the role of parental protectiveness as a mediator of this association. Participants were 316 parents of children aged 7-12 years with FAPD. Parents completed measures of perceived child self-efficacy when in pain, their own protective responses to their child's pain, child gastrointestinal (GI) symptom severity, and child functional disability. Parent-perceived child self-efficacy was inversely associated with parent-reported child GI symptom severity and disability, and parental protectiveness mediated these associations. These results suggest that parents who perceive their child to have low self-efficacy to cope with pain respond more protectively when they believe he/she is in pain, and this, in turn, is associated with higher levels of GI symptoms and disability in their child. This finding suggests that directly addressing parent beliefs about their child's ability to manage pain should be included as a component of FAPD, and potentially other child treatment interventions.

Personal and Contextual Factors Affecting the Functional Ability of Children and Adolescents with Chronic Pain: A Systematic Review

OBJECTIVE

Chronic pain can significantly impair functioning of children and adolescents; however, evidence suggests that current psychological approaches have limited effect on functioning post treatment. The objective of this review is to present the current evidence for the personal and contextual factors that affect functioning and disability of children and adolescents with chronic pain, to support the evolution of new treatments.

METHOD

Key word searches were conducted in PsycINFO, MEDLINE via Ovid, CINAHL, and PubMed from 1995 to October 2014. Studies were included if they (1) were written in English, (2) included children or adolescents with chronic pain (>3 mo), (3) had at least 1 personal attribute or 1 contextual factor, (4) had 1 measure of functional ability, and (5) had reported correlations between personal or contextual factors and functional measure.

RESULTS

Thirty-three studies were identified which met all inclusion criteria. Several personal factors (depression, anxiety, pain intensity, and catastrophizing) and contextual/environmental factors (parenting characteristics) were consistently associated with higher levels of disability, whereas evidence for other factors was less consistent. Complex interactions between personal and contextual factors were reported. Child physical/cognitive capacities, teacher/peer behaviors, and broader cultural and environmental social systems, received little attention.

CONCLUSION

Several parent and child factors were consistently linked with functional disability, whereas better family functioning was associated with functional ability. Applying an ecological framework, assisted identification of areas for further research, and provides direction for treatments that may be more effective in optimizing long-term functional outcomes, extending current psychological approaches.

Cognitive mediators of treatment outcomes in pediatric functional abdominal pain

OBJECTIVES

Cognitive-behavioral (CB) interventions improve outcomes for many pediatric health conditions, but little is known about which mechanisms mediate these outcomes. The goal of this study was to identify whether changes in targeted process variables from baseline to 1 week posttreatment mediate improvement in outcomes in a randomized controlled trial of a brief CB intervention for idiopathic childhood abdominal pain.

MATERIALS AND METHODS

Two hundred children with persistent functional abdominal pain and their parents were randomly assigned to 1 of 2 conditions: a 3-session social learning and CB treatment (N=100), or a 3-session educational intervention controlling for time and attention (N=100). Outcomes were assessed at 3-, 6-, and 12-month follow-ups. The intervention focused on altering parental responses to pain and on increasing adaptive cognitions and coping strategies related to pain in both parents and children.

RESULTS

Multiple mediation analyses were applied to examine the extent to which the effects of the social learning and CB treatment condition on child gastrointestinal (GI) symptom severity and pain as reported by children and their parents were mediated by changes in targeted cognitive process variables and parents' solicitous responses to their child's pain symptoms. Reductions in parents' perceived threat regarding their child's pain mediated reductions in both parent-reported and child-reported GI symptom severity and pain. Reductions in children's catastrophic cognitions mediated reductions in child-reported GI symptom severity but no other outcomes. Reductions in parental solicitousness did not mediate outcomes.

DISCUSSION

Results suggest that reductions in reports of children's pain and GI symptoms after a social learning and CB intervention were mediated at least in part by decreasing maladaptive parent and child cognitions.

Attachment and adjustment in adolescents and young adults with a history of pediatric functional abdominal pain

OBJECTIVES

This study tested predictions of the Attachment-Diathesis Model (ADM) of Chronic Pain in a cross-sectional sample of adolescents and young adults with a history of childhood functional abdominal pain (FAP). ADM posits that attachment anxiety is a diathesis for poor adjustment (physical health, mental health, and functioning) in the context of chronic pain and that pain self-efficacy, pain threat appraisal, and passive coping mediate this effect.

METHODS

Participants (N=261) were recruited from a database of consecutive new patients evaluated for abdominal pain at a pediatric gastroenterology clinic. Participants' mean age at the follow-up assessment was 21 years. Structural equation modeling was used to test the fit of our conceptual model to the data.

RESULTS

Model fit was good (comparative fit index=0.971, the Tucker-Lewis index=0.940, root mean square error of approximation=0.067). Attachment anxiety significantly predicted poorer health in both the mental and physical domains. Model fit was consistent with our hypothesis that pain self-efficacy mediates the effect of attachment anxiety on passive coping and that passive coping, in turn, mediates the effect of pain self-efficacy and pain threat appraisal on mental and physical health.

DISCUSSION

Among individuals with a childhood history of FAP, those with anxious attachment may be at higher risk for poor physical and mental health. Pain beliefs and coping may mediate the relation between anxious attachment and health outcomes and may serve as effective targets for intervention in chronic pain.

Validation of the Abdominal Pain Index using a revised scoring method

OBJECTIVE

Evaluate the psychometric properties of child- and parent-report versions of the four-item Abdominal Pain Index (API) in children with functional abdominal pain (FAP) and healthy controls, using a revised scoring method that facilitates comparisons of scores across samples and time.

METHODS

Pediatric patients aged 8-18 years with FAP and controls completed the API at baseline (N = 1,967); a subset of their parents (N = 290) completed the API regarding the child's pain. Subsets of patients completed follow-up assessments at 2 weeks (N = 231), 3 months (N = 330), and 6 months (N = 107). Subsets of both patients (N = 389) and healthy controls (N = 172) completed a long-term follow-up assessment (mean age at follow-up = 20.21 years, SD = 3.75).

RESULTS

The API demonstrated good concurrent, discriminant, and construct validity, as well as good internal consistency.

CONCLUSION

We conclude that the API, using the revised scoring method, is a useful, reliable, and valid measure of abdominal pain severity.

Visceral hypersensitivity and electromechanical dysfunction as therapeutic targets in pediatric functional dyspepsia

Functional gastrointestinal disorders (FGID) are common clinical syndromes diagnosed in the absence of biochemical, structural, or metabolic abnormalities. They account for significant morbidity and health care expenditures and are identifiable across variable age, geography, and culture. Etiology of abdominal pain associated FGIDs, including functional dyspepsia (FD), remains incompletely understood, but growing evidence implicates the importance of visceral hypersensitivity and electromechanical dysfunction. This manuscript explores data supporting the role of visceral hypersensitivity and electromechanical dysfunction in FD, with focus on pediatric data when available, and provides a summary of potential therapeutic targets.

Impact of eating restriction on gastrointestinal motility in adolescents with IBS

OBJECTIVE

Gastrointestinal disturbances as a result of changes in eating patterns have been described in eating disorders. Many patients who experience irritable bowel syndrome report changes in eating patterns as a way to cope with their symptoms. Little is known about the consequences of these practices. The aim of this study was to explore whether repeated eating restriction (defined as not eating ≥ 4 hours while hungry) is associated with motility disturbances.

METHODS

Of 17 patients with irritable bowel syndrome, subjects were divided into those who habitually restrict their eating (n = 8) and those without eating restriction (n = 9) (age range 15-21, mean 19.2; 64.7% girls). Whole-gut transit time was measured by radiopaque markers, gastric sensitivity was measured by water load test (drinking max of 800 mL of water in 5 minutes or until full), and gastric dysrhythmias by an electrogastrogram.

RESULTS

Restrictors drank less water (mean 464.4 mL) than nonrestrictors (mean 613 mL; P = 0.02). No difference was found in gastric dysrhythmias (62.5% vs 77.8%; P = 0.5). Whole-gut transit tended to be slower in the restrictors (mean 51.0 hours) than in nonrestrictors (mean 37.5 hours), but this was not significant.

CONCLUSIONS

Eating restriction appears to be associated with increased gastric sensation. More data are needed from larger studies to determine whether eating behaviors are associated with other motility disturbances.

A practical guide and perspectives on the use of experimental pain modalities with children and adolescents

Use of experimental pain is vital for addressing research questions that would otherwise be impossible to examine in the real world. Experimental induction of pain in children is highly scrutinized given the potential for harm and lack of direct benefit to a vulnerable population. However, its use has critically advanced our understanding of the mechanisms, assessment and treatment of pain in both healthy and chronically ill children. This article introduces various experimental pain modalities, including the cold pressor task, the water load symptom provocation test, thermal pain, pressure pain and conditioned pain modulation, and discusses their application for use with children and adolescents. It addresses practical implementation and ethical issues, as well as the advantages and disadvantages offered by each task. The incredible potential for future research is discussed given the array of experimental pain modalities now available to pediatric researchers.

Eosinophils and mast cells as therapeutic targets in pediatric functional dyspepsia

There is an increasing appreciation for the importance of inflammation as a pathophysiologic entity that contributes to functional gastrointestinal disorders including functional dyspepsia (FD). Importantly, inflammation may serve as a mediator between psychologic and physiologic functions. This manuscript reviews the literature implicating two inflammatory cell types, mast cells and eosinophils, in the generation of dyspeptic symptoms and explores their potential as targets for the treatment of FD. There are a number of inciting events which may initiate an inflammatory response, and the subsequent recruitment and activation of mast cells and eosinophils. These include internal triggers such as stress and anxiety, as well as external triggers such as microbes and allergens. Previous studies suggest that there may be efficacy in utilizing medications directed at mast cells and eosinophils. Evidence exists to suggest that combining “anti-inflammatory” medications with other treatments targeting stress can improve the rate of symptom resolution in pediatric FD.

Functional abdominal pain patient subtypes in childhood predict functional gastrointestinal disorders with chronic pain and psychiatric comorbidities in adolescence and adulthood

Although pediatric functional abdominal pain (FAP) has been linked to abdominal pain later in life, childhood predictors of long-term outcomes have not been identified. This study evaluated whether distinct FAP profiles based on patterns of pain and adaptation in childhood could be identified and whether these profiles predicted differences in clinical outcomes and central sensitization (wind-up) on average 9years later. In 843 pediatric FAP patients, cluster analysis was used to identify subgroups at initial FAP evaluation based on profiles of pain severity, gastrointestinal (GI) and non-GI symptoms, pain threat appraisal, pain coping efficacy, catastrophizing, negative affect, and activity impairment. Three profiles were identified: high pain dysfunctional, high pain adaptive, and low pain adaptive. Logistic regression analyses controlling for age and sex showed that, compared with pediatric patients with the low pain adaptive profile, those with the high pain dysfunctional profile were significantly more likely at long-term follow-up to meet criteria for pain-related functional gastrointestinal disorder (FGID) (odds ratio: 3.45, confidence interval: 1.95 to 6.11), FGID with comorbid nonabdominal chronic pain (odds ratio: 2.6, confidence interval: 1.45 to 4.66), and FGID with comorbid anxiety or depressive psychiatric disorder (odds ratio: 2.84, confidence interval: 1.35 to 6.00). Pediatric patients with the high pain adaptive profile had baseline pain severity comparable to that of the high pain dysfunctional profile, but had outcomes as favorable as the low pain adaptive profile. In laboratory pain testing at follow-up, high pain dysfunctional patients showed significantly greater thermal wind-up than low pain adaptive patients, suggesting that a subgroup of FAP patients has outcomes consistent with widespread effects of heightened central sensitization.

Functional abdominal pain and irritable bowel syndrome in children and adolescents

Functional abdominal pain (FAP) and irritable bowel syndrome (IBS) are both associated with recurrent abdominal pain and are among the most commonly diagnosed medical problems in pediatrics. The majority of patients with mild complaints improve with reassurance and time. For a distinct subset of patients with more severe and disabling illness, finding effective treatment for these disorders remains a challenge. Based on the biopsychosocial model of functional disease, the Rome III criteria have helped frame FAP and IBS in terms of being a positive diagnosis and not a diagnosis of exclusion. However, the lack of a single, proven intervention highlights the complex interplay of pathologic mechanisms likely involved in the development of childhood FAP and IBS and the need for a multidisciplinary, integrated approach. This article discusses the epidemiology, proposed mechanisms, clinical approach and therapeutic options for the management of FAP and IBS in children and adolescents.

Children's pain threat appraisal and catastrophizing moderate the impact of parent verbal behavior on children's symptom complaints

OBJECTIVE

We tested the hypothesis that pain threat appraisal and catastrophizing by children with functional abdominal pain (FAP) will moderate the relation between parent verbal behavior and children's symptom complaints following experimentally induced visceral discomfort.

METHODS

Thirty-three pediatric patients with FAP and their parents participated. Children completed measures of pain threat appraisal and catastrophizing. Weeks later they completed the Water Load Symptom Provocation Test to induce visceral discomfort. Spontaneous parent-child interactions during child discomfort were audiotaped and coded for content.

RESULTS

Parent symptom-related talk was associated with more child symptom complaints and parent non-symptom-related talk with fewer child complaints. The relation between symptom talk and complaints was greater for children with high catastrophizing. Non-symptom talk was associated with fewer complaints for children with high threat appraisals.

CONCLUSIONS

Child characteristics should be considered in research on the relation between parent behavior and children's symptom complaints.

No change in rectal sensitivity after gut-directed hypnotherapy in children with functional abdominal pain or irritable bowel syndrome

OBJECTIVES

Gut-directed hypnotherapy (HT) has recently been shown to be highly effective in treating children with functional abdominal pain (FAP) and irritable bowel syndrome (IBS). This study was conducted to determine the extent to which this treatment success is because of an improvement in rectal sensitivity.

METHODS

A total of 46 patients (aged 8-18 years) with FAP (n=28) or IBS (n=18) were randomized to either 12 weeks of standard medical therapy (SMT) or HT. To assess rectal sensitivity, a pressure-controlled intermittent distension protocol (barostat) was performed before and after the therapy.

RESULTS

Rectal sensitivity scores changed in SMT patients from 15.1+/-7.3 mm Hg at baseline to 18.6+/-8.5 mm Hg after 12 weeks of treatment (P=0.09) and in HT patients from 17.0+/-9.2 mm Hg to 22.5+/-10.1 mm Hg (P=0.09). The number of patients with rectal hypersensitivity decreased from 6 of 18 to 0 of 18 in the HT group (P=0.04) vs. 6 of 20 to 4 of 20 in the SMT group (P=0.67). No relationship was established between treatment success and rectal pain thresholds. Rectal sensitivity scores at baseline were not correlated with intensity, frequency, or duration of abdominal pain.

CONCLUSIONS

Clinical success achieved with HT cannot be explained by improvement in rectal sensitivity. Furthermore, no association could be found between rectal barostat findings and clinical symptoms in children with FAP or IBS. Further studies are necessary to shed more light on both the role of rectal sensitivity in pediatric FAP and IBS and the mechanisms by which hypnotherapy results in improvement of clinical symptoms.

Rectal sensory threshold for pain is a diagnostic marker of irritable bowel syndrome and functional abdominal pain in children

OBJECTIVE

To evaluate the diagnostic value of the rectal sensory threshold for pain (RSTP) in children and adolescents with chronic abdominal pain.

STUDY DESIGN

Fifty-one patients (25 girls; median age 14.2 years; range 8.4-17.6) with abdominal pain >2 months underwent a series of rectal distensions with an electronic barostat. RSTP and viscerosomatic referrals were assessed. Three months after the barostat, the final diagnosis was documented.

RESULTS

Thirty-five patients had a functional gastrointestinal disorder (FGID) (irritable bowel syndrome or functional abdominal pain), and 16 had an organic disease. RSTP was lower in the FGID group than in the organic disease group (25.4mm Hg vs 37.1mm Hg; P = .0002). At the cutoff of 30mm Hg, the RSTP measurement for the diagnosis of FGID had a sensitivity of 94% and a specificity of 77%. Both groups similarly reported aberrant viscerosomatic projections.

CONCLUSION

In children, RSTP is a diagnostic marker of irritable bowel syndrome and functional abdominal pain. Viscerosomatic referrals are similar in children with FGID and organic diseases.

Functional gastrointestinal disorders: past and present

BACKGROUND

Chronic abdominal pain is a common complaint in childhood and adolescence. Despite decades of clinical observations and research, it still poses a challenge to pediatric health care professionals. The aim of this review is to highlight the epidemiology of pediatric chronic abdominal pain and to describe the pathogenesis of this disorder, its clinical manifestations, evaluation and therapeutic options.

DATA SOURCES

Articles on chronic abdominal pain in the recent years from PubMed, MEDLINE, and reference textbooks were reviewed.

RESULTS

Chronic abdominal pain, a functional gastrointestinal disorder (FGID), is a multifactorial condition that results from a complex interaction between psychosocial and physiologic factors via the brain-gut axis. A thorough history coupled with a complete physical examination and normal screening studies rule out an organic cause in 95% of the cases. It is highly important for the physician to establish a trusting relationship with the child and parents because successful treatment including modification of physical and psychological stress factors, dietary changes, and drug therapy depends greatly on education, reassurance and active psychological support.

CONCLUSIONS

FGIDs are a cause of great anxiety, distress and morbidity in children as well as adults. As our understanding of these conditions improves, our therapeutic interventions will progress not only to overcome them but also to intervene early in the disease course so as to limit long-term impact.