Colonic manifestations of multiple endocrine neoplasia type 2B: report of four cases

Pediatric Intestinal Pseudo-obstruction in the Era of Genetic Sequencing

PURPOSE OF REVIEW

The purpose of this review is to discuss current knowledge on pediatric intestinal pseudo-obstruction. We will also review new mutations that have been identified through advancement in genetic testing, allowing for a better understanding of the underlying mechanisms of intestinal dysmotility and potential etiologies.

RECENT FINDINGS

With the advancements in genetic testing, new mutations have been identified in the diagnosis of megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS), a disorder leading to pediatric pseudo-obstruction. MYLK, LMOD1, MYL9, and MYH11 encode for various proteins within smooth muscle cells; abnormalities within these proteins lead to abnormal intestinal smooth muscle contractions. Chronic intestinal pseudo-obstruction (CIPO) is defined by symptoms of bowel obstruction in the absence of a lumen-occluding lesion. CIPO is a heterogeneous group of disorders caused by abnormalities in the enteric neurons, intestinal smooth muscle, and/or the interstitial cells of Cajal (ICC). Symptoms can be non-specific and etiologies include both primary and secondary causes of CIPO that contribute to the delay in recognizing this condition and making the correct diagnosis. Chronic intestinal pseudo-obstruction has been recognized in both adults and children with fundamental differences in the etiology, symptom onset, clinical features and natural history of this disorder. For this reason, it has been considered a separate entity referred to as pediatric intestinal pseudo-obstruction (PIPO).

Paediatric Intestinal Pseudo-obstruction: Evidence and Consensus-based Recommendations From an ESPGHAN-Led Expert Group

OBJECTIVES

Chronic intestinal pseudo-obstructive (CIPO) conditions are considered the most severe disorders of gut motility. They continue to present significant challenges in clinical care despite considerable recent progress in our understanding of pathophysiology, resulting in unacceptable levels of morbidity and mortality. Major contributors to the disappointing lack of progress in paediatric CIPO include a dearth of clarity and uniformity across all aspects of clinical care from definition and diagnosis to management. In order to assist medical care providers in identifying, evaluating, and managing children with CIPO, experts in this condition within the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition as well as selected external experts, were charged with the task of developing a uniform document of evidence- and consensus-based recommendations.

METHODS

Ten clinically relevant questions addressing terminology, diagnostic, therapeutic, and prognostic topics were formulated. A systematic literature search was performed from inception to June 2017 using a number of established electronic databases as well as repositories. The approach of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) was applied to evaluate outcome measures for the research questions. Levels of evidence and quality of evidence were assessed using the classification system of the Oxford Centre for Evidence-Based Medicine (diagnosis) and the GRADE system (treatment). Each of the recommendations were discussed, finalized, and voted upon using the nominal voting technique to obtain consensus.

RESULTS

This evidence- and consensus-based position paper provides recommendations specifically for chronic intestinal pseudo-obstruction in infants and children. It proposes these be termed paediatric intestinal pseudo-obstructive (PIPO) disorders to distinguish them from adult onset CIPO. The manuscript provides guidance on the diagnosis, evaluation, and treatment of children with PIPO in an effort to standardise the quality of clinical care and improve short- and long-term outcomes. Key recommendations include the development of specific diagnostic criteria for PIPO, red flags to alert clinicians to the diagnosis and guidance on the use of available investigative modalities. The group advocates early collaboration with expert centres where structured diagnosis and management is guided by a multi-disciplinary team, and include targeted nutritional, medical, and surgical interventions as well as transition to adult services.

CONCLUSIONS

This document is intended to be used in daily practice from the time of first presentation and definitive diagnosis PIPO through to the complex management and treatment interventions such as intestinal transplantation. Significant challenges remain to be addressed through collaborative clinical and research interactions.

Multiple endocrine neoplasia 2B: Differential increase in enteric nerve subgroups in muscle and mucosa

Multiple endocrine neoplasia 2B (MEN2B) is a rare syndrome caused by an activating mutation of the RET gene, leading to enteric gangliomatosis. This child presented with constipation at 1-mo old, was diagnosed with MEN2B by rectal biopsy at 4 mo, had thyroidectomy at 9 mo and a colectomy at 4 years. We studied the extent of neuronal and nerve fibre proliferation and which classes of enteric nerves are affected by examining the colon with multiple neuronal antibodies. Resected transverse colon was fixed, frozen, sectioned and processed for fluorescence immunohistochemistry labelling with antibodies against TUJ1, Hu, ChAT, NOS, VIP, SP and CGRP and cKit. Control transverse colon was from the normal margin of Hirschsprung (HSCR) colon (4-year-old) and a child with familial adenomatous polyposis (FAP, 12 year). Myenteric ganglia were increased in size to as wide as the circular muscle. There was a large increase in nerve cells and nerve fibres. ChAT-, NOS-, VIP- and SP-immunoreactive nerve fibres all increased in the myenteric ganglia. NOS-IR nerves preferentially increased in the muscle, while VIP and SP increased in submucosal ganglia and mucosal nerve fibres. The density of ICC was normal. RET overactivation in MEN2B lead to a large increase in intrinsic nerve fibres in the myenteric and submucosal ganglia, with a relative increase in NOS-IR nerve fibres in the circular muscle and VIP and SP in the submucosal ganglia and mucosa. The changes were associated with severe constipation resulting in colectomy at 4 years.

Identification of intestinal ganglioneuromatosis leads to early diagnosis of MEN2B: role of rectal biopsy

BACKGROUND/PURPOSE

Gastrointestinal symptoms are very common in patients with multiple endocrine neoplasia type 2B (MEN2B) syndrome. Herein, we present a case of intestinal ganglioneuromatosis (IGN) in MEN2B syndrome and a systematic literature review with a special focus on gastrointestinal symptoms prior to the diagnosis of MEN2B.

METHODS

Literature search was performed (years 1966-2015) using the "Pubmed" and "Scopus" databases. Search terms used were gastrointestinal, intestinal and MEN2B.

RESULTS

Literature search revealed 188 publications on MEN2B patients with gastrointestinal symptoms, providing a total of 55 patients including our own case. The far most common gastrointestinal symptom was constipation (72.7%). The onset of gastrointestinal symptoms occurred in 29 out of 55 cases (52.3%) below the age of 1year. However, MEN2B diagnosis was established at a median age of 13.0years (range 0-46years). The histological finding of IGN led to the diagnosis of MEN2B In 15 of 55 patients (27.3%) at a median age of 3years (range 0-31years).

CONCLUSION

Paying close attention to gastrointestinal problems in early childhood and taking a rectal biopsy that precisely screens for IGN offers the chance of diagnosing MEN2B syndrome early in infancy.

Orolabial signs are important clues for diagnosis of the rare endocrine syndrome MEN 2B. Presentation of two unrelated cases

Multiple endocrine neoplasia syndromes (MEN) are genetic disorders with glandular hyperplasia and consecutive malignant neoplasia. MEN type 2B is the least common form of these tumor syndromes. It presents with typical dysmorphic features, mucosal neuromas, ganglioneuromatosis, medullary thyroid carcinoma (MTC) and phaeochromocytoma. The prognosis depends on the presence of MTC. We have surprisingly found two unrelated patients with this syndrome at our department within two weeks. In the medical history of a 17-year-old boy, Crohn's disease had been considered because of abdominal pain and distention. He had marfanoid appearance and previously undergone minor surgeries for a large tongue with neuromas and hypertrophic gums. Two weeks later, a 10-year-old girl presented with a hard palpable mass on her neck. She had thickened lips, neuromas on the tongue and a solitary thyroid nodule. Genetic analysis was carried out in both patients and a heterozygous M918T mutation of the RET proto-oncogene was found. Laboratory tests and imaging studies were consistent with MTC. Phaeochromocytoma was not present. Both patients underwent total thyroidectomy and lymph node dissection. Histological examination confirmed the diagnosis of MTC. In conclusion, the initial diagnosis of MEN 2B should be suspected on the presence of typical facial/oral signs and gastrointestinal symptoms. Hormonal tests and imaging techniques of the thyroid and the adrenals can confirm the clinical diagnosis of MEN 2B and genetic analysis can prove its germline origin.

Diagnosis and management of gastrointestinal polyps: pediatric considerations

Painless, bright red, rectal bleeding with normal stool frequency and consistency is the hallmark presentation of colorectal polyps at any age. Most polyps in children are sporadic, usually isolated, colorectal juvenile polyps that do not require any further surveillance after they are removed. There is, however, increasing recognition of syndromes, including familial adenomatous polyposis, juvenile polyposis coli, Peutz-Jeghers syndrome, and infrequent conditions, such as PTEN hamartoma and hereditary mixed polyposis syndromes. The aim of this review is to allow the reader to correctly identify the patients who do not require follow-up and the smaller group of patients who do require follow-up because of syndromic polyp conditions.

Prolonged survival of a patient with multiple endocrine neoplasia type 2b and stage IV medullary thyroid carcinoma

OBJECTIVE

To present a case of multiple endocrine neoplasia type 2B (MEN2B) with a prolonged course.

METHODS

We describe the clinical, laboratory, and radiologic findings in a patient with MEN2B and review the various interventions during a period of approximately 3 decades.

RESULTS

In 1962, a 19-year-old man with a marfanoid body habitus presented with multiple thyroid nodules and neurofibromas of the tongue. Total thyroidectomy demonstrated multicentric medullary thyroid carcinoma with cervical lymph node metastatic involvement. At the time of the first description of the MEN2B syndrome, the patient was enrolled in a surveillance program. An increase in urinary metanephrines resulted in bilateral adrenalectomy for multinodular pheochromocytoma in 1972. Increased serum calcitonin levels and the appearance of cervical lymphadenopathy led to modified radical neck dissection 12 years after the initial diagnosis of medullary thyroid carcinoma. In 1975, angiography revealed extensive hepatic lesions metastatic from the medullary thyroid carcinoma; this finding was confirmed by open liver biopsy in 1988. The patient lived 16 years after the initial diagnosis of liver metastatic disease and died 29 years after the initial examination.

CONCLUSION

The 3-decade course of this patient not only represents a classic case of MEN2B but also allows us to present the history of this disease from its discovery to the current era of genetic testing and exemplifies the possibility of long-term survival in a patient with liver metastatic involvement from medullary thyroid carcinoma.

Ganglioneuromatous polyposis: a premalignant condition. Report of a case and review of the literature

A 40-year-old man with ganglioneuromatous polyposis and an aggressive coexisting colorectal cancer is described. Contrary to previous reports, we believe that ganglioneuromatous polyposis should be considered a premalignant condition.

Acute Intestinal Pseudo-obstruction

Acute pseudo-obstruction may manifest clinically in one of three forms--acute gastroparesis, ileus, and acute colonic pseudo-obstruction (Ogilvie's syndrome). Though formerly associated primarily with the postoperative state, these entities are increasingly recognized in association with a wide variety of major medical problems. There are few controlled studies to guide the clinician in the management of these disorders. Treatment remains largely empirical, and time-honored, based primarily on "bowel rest," nasogastric decompression, and supportive care. While a wide variety of pharmacologic approaches have been advocated, few have been subjected to, or survived, the rigors of a properly controlled trial. Neostigmine is a notable exception, and has been shown to be effective in Ogilvie's syndrome. Perforation is a significant threat in megacolon; colonoscopic, or surgical decompression may, therefore, be indicated. Both are associated with significant risks in this context, but may prevent progression to perforation with its attendant mortality. New approaches seek to exploit current concepts in the pathophysiology of ileus and megacolon but have not, as yet, achieved efficacy in human studies.