Rumination and vomiting in Prader-Willi syndrome

A multidisciplinary approach to the clinical management of Prader-Willi syndrome

Background

Prader–Willi syndrome (PWS) is a complex neuroendocrine disorder affecting approximately 1/15,000–1/30,000 people. Unmet medical needs of individuals with PWS make it a rare disease that models the importance of multidisciplinary approaches to care with collaboration between academic centers, medical homes, industry, and parent organizations. Multidisciplinary clinics support comprehensive, patient‐centered care for individuals with complex genetic disorders and their families. Value comes from improved communication and focuses on quality family‐centered care.

Methods

Interviews with medical professionals, scientists, managed care experts, parents, and individuals with PWS were conducted from July 1 to December 1, 2016. Review of the literature was used to provide support.

Results

Data are presented based on consensus from these interviews by specialty focusing on unique aspects of care, research, and management. We have also defined the Center of Excellence beyond the multidisciplinary clinic.

Conclusion

Establishment of clinics motivates collaboration to provide evidence‐based new standards of care, increases the knowledge base including through randomized controlled trials, and offers an additional resource for the community. They have a role in global telemedicine, including to rural areas with few resources, and create opportunities for clinical work to inform basic and translational research. As a care team, we are currently charged with understanding the molecular basis of PWS beyond the known genetic cause; developing appropriate clinical outcome measures and biomarkers; bringing new therapies to change the natural history of disease; improving daily patient struggles, access to care, and caregiver burden; and decreasing healthcare load. Based on experience to date with a PWS multidisciplinary clinic, we propose a design for this approach and emphasize the development of “Centers of Excellence.” We highlight the dearth of evidence for management approaches creating huge gaps in care practices as a means to illustrate the importance of the collaborative environment and translational approaches.

Gastro-oesophageal reflux - an important causative factor of severe tooth wear in Prader-Willi syndrome?

BACKGROUND

Prader-Willi syndrome (PWS) is the most common genetic human obesity syndrome and is characterized by hypotonia, endocrine disturbances, hyperphagia, obesity and mild mental retardation. Oral abnormalities, such as decreased salivary flow rates and extreme tooth wear, have also been described. Studies have shown a significant increase in reflux symptoms in individuals with obstuctive sleep apnoea syndrome and increased BMI, both of which are typical findings in PWS. Gastro-oesophageal reflux disease (GORD) has been identified in some individuals with PWS and is a significant intrinsic factor in dental tooth wear. The aim of this study was therefore to estimate the prevalence of GORD in adults and children and to evaluate a possible correlation between GORD and tooth wear in adults with PWS. They were all registered at the TAKO-centre.

RESULTS

Twenty-nine individuals, 17 adults with a mean age of 32.6 years (range 18-48) and 12 children with a mean age of 8.8 years (range 3-17), agreed to undergo 24-hour oesophageal pH monitoring, and 90% of those enrolled managed to complete the examination. Four children and eleven adults were diagnosed with pathological gastro-oesophageal reflux, which is defined as acid exposure (pH less than 4) more than 3.6 or 4.3 percent of the time, respectively. Manometry performed in the adult group showed a pathologically high lower oesophageal sphincter pressure in four of the five individuals who had normal oesophageal pH values (pH under 4 less than 4.3% of the time). The two groups (reflux and non-reflux) were well balanced according to BMI, genotype, tooth grinding and hyposalivation. However, twice as many individuals in the reflux group as in the non-reflux group reported high consumption of acidic foods and drinks. Increased tooth wear was significantly correlated with GORD in the two groups (reflux n=6 and non-reflux n=6).

CONCLUSIONS

The prevalence of gastro-oesophageal reflux is high in individuals with PWS. Tooth wear was strongly associated with GORD and acidic drinks, and both may be important aetiological factors underlying the extreme tooth wear in this group. Our data suggest a need for routine screening for GORD and dental wear in young individuals with Prader-Willi syndrome.

Subclinical dysphagia in persons with Prader-Willi syndrome

Prader-Willi Syndrome (PWS) is caused by a genetic imprinting abnormality resulting from the lack of expression of the paternal genes at 15q11-q13. Intellectual disability, low muscle tone, and life-threatening hyperphagia are hallmarks of the phenotype. The need for the Heimlich maneuver, death from choking, and pulmonary infection occur in a disproportionally high number of persons with PWS. The widely held belief is that eating behaviors are responsible for choking and aspiration; yet, no investigation had sought to determine if swallowing impairments were present in persons with PWS. To address this research and clinical gap, simultaneous videofluoroscopy and nasal respiratory signals were used to record swallowing function and breathing/swallowing coordination in 30 participants with PWS. Subjects consumed thin liquid and barium cookies under two randomized conditions as follows: (i) controlled (cues to swallow and standardized bolus sizes); (ii) spontaneous (no cues or bolus size control). Under videofluoroscopy, the cohort showed disordered pharyngeal and esophageal swallowing in both conditions with disturbances in timing, clearance, and coordination of swallowing with the respiratory cycle. No participant showed a sensory response such as attempting to clear residue or coughing; thereby supporting the lack of overt symptoms. We conclude that the high death rate from choking and pulmonary infection in children and adults with PWS may be related, in part, to underlying, asymptomatic dysphagia. The combination of rapid eating and dysphagia would increase the risk of aspiration-related morbidity and mortality. © 2016 Wiley Periodicals, Inc.

Microscopic structure of dental hard tissues in primary and permanent teeth from individuals with Prader-Willi syndrome

OBJECTIVE

severe tooth wear, in terms of both erosive wear and attrition, is a significant problem in individuals with Prader-Willi syndrome (PWS). The purpose of the present study was to describe the structure of enamel and dentine in primary and permanent teeth from individuals with PWS.

DESIGN

thirty-two primary and 10 permanent teeth representing 16 individuals with PWS were investigated in the study. The enamel surface was studied using scanning electron microscopy (SEM). The microscopic structure of enamel and dentine was studied using SEM, microradiography and light microscopy.

RESULTS

the microscopic structure of enamel and dentine was found to be normal with the exception of a slight increase of interglobular dentine (IGD). Severe erosive defects were observed in primary teeth and also in permanent teeth with long exposure to the oral environment.

CONCLUSION

the erosive enamel defects in individuals with PWS seem more related to the factors in the oral environment than to enamel structure which appeared normal. The occurrence of IGD indicate deficient mineralization but is probably of minor clinical significance. Gastro-oesophageal reflux is worthy of further investigation in individuals with Prader-Willi syndrome.

A descriptive study of colorectal function in adults with Prader-Willi Syndrome: high prevalence of constipation

BACKGROUND

Some patients with Prader-Willi Syndrome (PWS) have symptoms of constipation, but bowel function in PWS has never been systematically evaluated. The aim of the present study was to describe colorectal function in PWS by means of validated techniques.

METHODS

Twenty-one patients with PWS (14 women, age 17-47 (median = 32)) were evaluated with the Rome III constipation criteria, stool diary, digital rectal examination, rectal diameter assessed from transabdominal ultrasound, and total gastrointestinal transit time (GITT) determined with radio-opaque markers. Results were compared with those of healthy controls.

RESULTS

Among PWS patients able to provide information for Rome III criteria, 8/20 (40%) fulfilled the criteria for constipation. Most commonly reported symptoms were a feeling of obstructed defecation (8/19, 42%), <3 defecations per week (8/17, 47%), straining during defecation (7/19, 37%) and lumpy or hard stools (6/19, 32%). Rectal diameter did not differ between PWS (median 3.56 centimeters, range 2.24-5.36) and healthy controls (median 3.42 centimeters, range 2.67-4.72) (p = 0.96), but more PWS patients (13/20; 65%) than healthy controls (3/25; 12%) (p < 0.001) had fecal mass in the rectum. Median GITT was 2.0 days (range 0.5-4.4) in PWS versus 1.6 (range 0.7-2.5) in the control group (p = 0.26). However, GITT was >3 days in 5/21 (24%) of PWS and none of the controls (p = 0.047).

CONCLUSION

Constipation is very common in PWS. Patients with PWS have an increased prevalence of prolonged GITT and palpable stools in the rectum at digital rectal examination.

The use of medical care and the prevalence of serious illness in an adult Prader-Willi syndrome cohort

INTRODUCTION

Adults with Prader-Willi syndrome (PWS) have an increased occurrence of several medical conditions. We report on the consequences of high morbidity rates such as prevalence rate of hospital admissions, medication use and surgery in a Dutch cohort of adults with PWS. Special attention is paid to causes and symptoms of serious illness.

METHOD

Participants were contacted via the Dutch Prader-Willi Parent Association and through physicians specializing in persons with ID. The persons with PWS and their main caregivers were visited at home. Information was collected through semi-structured interviews on 102 adults with PWS.

RESULTS

The need for medical care in the neonatal period is associated with hypotonia and feeding problems. Hospital admissions for respiratory tract infections are frequent. During childhood most hospital admissions were due to PWS syndrome specific surgery. During adolescence hospital admissions occurred for scoliosis surgery and endocrine evaluations. At adult age, hospitalization was associated with inguinal hernia surgery, diabetes mellitus, psychosis, erysipelas, water and drug intoxications. In the older group, respiratory infections were again the main reason for hospital admissions. Frequently used medications at adult age included psychotropics, laxatives, anti-diabetics and dermatologic preparations. Abnormal drinking patterns, problems with anesthesia, decreased ability to vomit, abnormal pain awareness and unpredictable fever responses were frequent and often lead to delayed diagnoses of serious conditions.

DISCUSSION

People with PWS are frequent users of medical-care. Reasons for hospitalization and medication use are age specific. Knowledge on the different presentation of symptoms in people with PWS is needed. In case of unexplained illness, disturbances of consciousness and behavioral changes in people with PWS, an infection should be ruled out in the first place. Information from this study may help in preventing conditions and recognizing conditions in an early stage. Adequate preventive management and treatment of PWS related morbidity, could reduce medical care use in the long term and could improve quality adjusted life years.

Gastric rupture and necrosis in Prader-Willi syndrome

Hyperphagia and obesity are common features in individuals with Prader-Willi syndrome (PWS). Demographic and cause-of-death data from individuals with PWS were obtained through a national support organization. Four reports of unexpected mortality due to gastric rupture and necrosis were found in 152 reported deaths, accounting for 3% of the causes of mortality. Four additional individuals were suspected to have gastric rupture. Vomiting and abdominal pain, although rare in PWS, were frequent findings in this cohort. The physician should consider an emergent evaluation for gastric rupture and necrosis in individuals with PWS who present with vomiting and abdominal pain.

Deaths due to choking in Prader-Willi syndrome

Prader-Willi syndrome (PWS) is the most common known syndromic cause of life-threatening obesity, yet few studies have examined the causes of death in PWS. The objective of this study was to examine the contribution of choking leading to mortality in PWS. In 1999, a brief survey was made available from the Prader-Willi Syndrome Association (USA) bereavement program, which documented demographic data and causes of death. Families were subsequently offered the opportunity to fill out a detailed questionnaire and additional forms to release medical records. Demographic information was available on 178 deceased individuals with PWS, and cause of death available on 152 individuals. Fifty-four families completed questionnaires. Of the deceased individuals with completed questionnaires, 34% reported a history of choking. Choking was listed by familial report as the cause of death in 12 (7.9%) of 152 subjects with an average age of 24 years (range 3-52 years; median 22.5 years) at death from choking. Only two of these individuals were less than 8 years of age. The data suggest that risks associated with choking are different in the PWS population compared with others. Potential causes of increased choking in PWS include poor oral/motor coordination, poor gag reflex, hypotonia, hyperphagia, decreased mastication, and voracious feeding habits. We recommend implementation of preventive measures and education for families and group home care providers for all individuals with PWS including the Heimlich maneuver, supervised meals, better food preparation, and diet modification to avoid high-risk choking items.

A case of duodenal web occurring in Prader-Willi syndrome

Vomiting and abdominal symptoms are uncommonly seen in children with Prader-Willi syndrome (PWS). A case is described of a child with PWS who presented with vomiting, abdominal distension and abdominal pain due to a duodenal web causing gross gastric distension. Prompt attention to the onset of such clinical features in children with PWS may prevent excess morbidity and complications.