Wednesday, December 25, 2019

Following cause intrinsic mechanical obstruction of oesophagus EXCEPT.. Barrets oesophagus. Schatzaki's ring



Following cause intrinsic mechanical obstruction of oesophagus EXCEPT:
A- Duplication cyst… This
B- Carcinoma. True
C- Barrets oesophagus. True
D- Schatzaki's ring. True
E- Oesophageal webs. True
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Introduction:
Duplication cysts constitute an extremely rare entity. These are very low prevalence congenital anomalies that can be located at any level of the gastrointestinal tract. Of all of them, those located in the stomach and in the appendix are the least frequent.

The diagnosis is made in more than half of the cases in early childhood, since at this age they are usually symptomatic. On the contrary, in adulthood these cysts are usually indolent and their diagnosis constitutes an incidental finding. In more than 50% of cases they are usually associated with other malformations, mainly gastrointestinal and vertebral, and sometimes they can be complicated with hemorrhages, fistulization or even with malignant transformation of your epithelium. The diagnostic techniques commonly used, such as abdominal CT and MRI, present multiple difficulties for their characterization and diagnostic errors with solid lesions are not uncommon. Several articles have recently been published that highlight the diagnostic efficacy of echoendoscopy in the characterization of these entities compared to the conventional imaging techniques described.

Today a therapeutic algorithm is not yet established. Surgery is recommended for symptomatic cases or in which there has been a complication, but so far there is no consensus as to the attitude to be followed in asymptomatic cases. This constitutes a problem, especially if one considers the risk of malignant transformation of these lesions.

Despite being described already in 1911 by Wendel, since then there have been very few published cases. Therefore, the case of a gastric duplication cyst is presented in an adult patient diagnosed by endoscopic ultrasound-guided puncture and a subsequent review of the literature.



Clinical case:
This is a 39-year-old male referred to our Ecoendoscopy Unit to record the nature of a submucosal lesion located in the gastric slope of the esophageal-gastric junction. The patient begins his medical study at the Otolaryngology Service where he consults for pharyngeal discomfort. After the examinations carried out by this service, it is decided to perform an upper digestive endoscopy, where a rounded lesion, with a preserved mucosa of a diameter of approximately 1.5 cm greater, is evidenced at 36 cm of dental arch. Biopsies are taken by endoscopy, the histological result being inconclusive. In the presence of a submucosal lesion, the nature of which cannot be filmed by endoscopic imaging or after the histological study of the biopsies, the patient is referred to our center for an echoendoscopy (USE).

EUS is performed on an outpatient basis, under vital signs monitoring and conscious sedation based on midazolam and pethidine. A Pentax EG3830UX linear echoendoscope coupled to a Hitachi 8500 ultrasound is used. A small, well-defined anechoic lesion, cystic in appearance, is identified 36 cm from the dental arch, which appears to depend on the submucosa, 14 x 6 mm in maximum diameters ( Figs. 1 and 2). The presence of abdominal or mediastinal lymphadenopathy is not identified by the ultrasonographic study and the integrity of the vascular axis is demonstrated. Once the lesion to be punctured is identified, an ultrasound study with color doppler is performed to avoid vascular formations and identify the most appropriate path to perform the puncture. For this puncture, the 19 G Echotip Wilson-Cook needle is used. First, the needle sheath is removed a few centimeters through the working channel until it is visualized either gastroscopically- or ecoendoscopically; Next, the lesion is punctured using the needle inside the sheath. Once its position inside the lesion is verified, the stylet is removed (which is used to prevent possible contamination of the sample) and needle advance maneuvers are performed in order to extract as much material as possible of the injury. In our case we have used an aspiration syringe to increase the cellularity of the sample. Two passes are made on the lesion until the pathologist, present in the examination room, confirms the sufficiency of the sample.

Discussion:
Duplication cysts are cystic formations adjacent to a portion of the gastrointestinal tract with which they share a wall. These are cystic tumors covered by mucosa, generally similar to that of the adjacent anatomical region. They are congenital anomalies of very low prevalence, which can be located at any level of the gastrointestinal tract: from the mouth to the anus. In descending order of frequency they are located in the ileum, esophagus, jejunum, colon, stomach and appendix. Therefore, as we have just mentioned, if gastrointestinal duplication cysts are rare, gastric duplication cysts are even more rare, representing only between 2 and 8% of all these entities, according to the series.

These structures are the result of alterations in embryonic development. Several etiopathogenic theories have been postulated that try to explain its formation: a) persistence of a vacuole formed in the solid phase of the development of the embryonic intestine or of an embryonic diverticulum; b) failure in the fusion and recanalization of the intestinal longitudinal folds which would allow a passage of a bridge of epithelial tissue; and c) the formation of a traction diverticulum due to a failure in the usual development of the notochord and endoderm that would eventually cause the duplication cyst. However, there is still no theory that satisfactorily explains the development of all duplication cysts. Gastric duplication cysts originate dorsally in the primitive intestine, so most of them are located in the greater curvature, generally at the distal level and only 5.5% of them are in the lesser curvature.

Duplication cysts mainly affect women, with a prevalence of up to double over men, without observing a family trend. They are usually diagnosed at an early age, more than 60% of cases in the first year of life, being very rare diagnosis in adulthood. The clinical manifestations depend essentially on the patient's age, location and size of the lesions. In adults they are usually asymptomatic, so, as in our case, the diagnosis is made incidentally in the course of an examination indicated for another reason. In our case, a 39-year-old male had an echoendoscopic study of a submucosal lesion, the lesion described being an incidental finding that did not justify the clinical picture.

Symptomatic forms are characterized by recurrent abdominal pain, palpable mass, vomiting, weight loss or growth retardation. Other manifestations that can be observed are related to the development of complications such as fever due to cyst superinfection, gastrointestinal bleeding, fistulization, torsion of your pedicle, or pictures of occlusion or intestinal sub-occlusion. It has even been described the case of a pyloric duplication cyst in a newborn simulating benign pyloric hypertrophy. In half of the cases there are associated malformations, the most frequent being esophageal duplications, followed by vertebral abnormalities.

Rowling in 1959 defined a series of essential characteristics characteristic of duplication cysts, such as proximity to the digestive tract, a common blood supply, a layer of smooth muscle that shares with the gastrointestinal wall, and is lined by digestive epithelium. However, cases have been described with heterotopic mucosa such as respiratory epithelium and also pancreatic mucosa. The presence of pancreatic and gastric mucosa are the most associated to complications due to the possibility of development of peptic ulcer or acute pancreatitis. Very few cases of malignant transformation have been described, usually in the form of adenocarcinomas and squamous carcinomas, but also more infrequently as neuroendocrine tumors with different degrees of malignancy. The differential diagnosis should be made with cystic neoplasms, or with cystic degeneration, such as intraductal papillary mucinous tumor, mucinous cystadenoma, lymphangioma and other benign lesions such as simple cyst, lymphoepithelial cyst, pancreatic pseudocyst, inclusion cysts or parasitic cysts. Therefore, for the diagnostic confirmation and especially to rule out the malignant transformation of the cyst, the cytohistological assessment of the lesion is necessary.

Abdominal CT and MRI allow duplication cysts to be identified, but diagnostic errors with solid lesions reach up to 70% according to the series published by Eloubeidi. The variability of content of these entities and the presence of a thick proteinaceous content in any of these cysts are the main causes of error. EUS is a fundamental technique in the diagnosis and characterization of submucosal lesions, also allowing to define with high precision the relationship of the cyst with the adjacent gastrointestinal wall and differentiate between cystic and solid lesions. So far there are nine articles in English literature that specifically mention the usefulness of endoscopic ultrasound in the diagnosis of duplication cysts, including three cases of gastric localization. Most authors show that EUS is a safe technique and one that has the highest diagnostic efficacy for this type of lesions. EUS also allows cytohistological material to be obtained, which is essential for differential diagnosis with other entities, as well as to rule out the presence of neoplastic transformation of the cysts themselves. Although there is no histological study in all published cases, cytology is considered by many authors as a fundamental pillar in the diagnosis of these lesions. Endoscopic ultrasound shows a greater diagnostic sensitivity than conventional endoscopy in the characterization of submucosal lesions of the gastrointestinal tract and fine needle aspiration puncture allows greater efficiency in obtaining material for histological study than conventional endoscopy allows. For all this, endoscopic ultrasound, and especially, puncture guided by endoscopic ultrasonography, has been proposed as the technique of choice in the diagnosis and characterization of these lesions. Most published cases show a cyst size greater than ours, from 2 cm to 15 cm. The fact that a puncture to a lesion of cystic features of such a small size could be practiced could be a topic of discussion.

So far there is no diagnostic-therapeutic algorithm for this type of lesions. In symptomatic cases, surgery is recommended, without any discussion, being the surgical procedure of controversial choice. Some authors also advocate surgical removal even in asymptomatic cases, based on the prevention of complications and the risk of neoplastic degeneration. Others recommend conservative treatment, especially if we consider that these lesions in adults are an incidental finding and that the cases described with malignant transformation are anecdotal. Even a case of spontaneous resolution of a cyst of duplication at the mediastinal level has been described. Zambudio et al. They propose a series of criteria for surgical excision of mediastinal cysts: symptomatic cysts, infection of the same, trachea compression, progressive growth, diagnosis in childhood, location or atypical characteristics. Many of these criteria could be reasonably extrapolated to gastric duplication cysts.