Medical brain notes 15

  Congenital and Mechanical Disorders   Tracheoesophageal fistula  may arise as a congenital connection between the esopha-gus and trachea that is often associated with esophageal atresia. It is often discovered soon after birth because of aspiration. In adults the condition can occur secondary to malignancy, trauma, or iatrogenic causes.   Esophageal webs  are web-like protrusions of the esophageal mucosa into the lumen   which typically present with dysphagia. Plummer-Vinson syndrome is a disease of middle-aged women characterized by esophageal webs, iron deficiency anemia, and increased risk of carcinoma. Schatzki rings are web-like narrowings at the gastro-esophageal junction.   Achalasia  is a failure of the lower esophageal sphincter (LES) to relax with swallow-ing. The etiology is unknown in most cases; in South America, achalasia may be caused by Chagas disease. Presentation is with progressive dysphagia. The esopha-gus is characteristical...

  Congenital Disorders   Pyloric stenosi s   is a congenital stenosis of the pylorus due to marked muscular   hypertrophy of the pyloric sphincter, resulting in gastric outlet obstruction. It affects male infants more than females. It is associated with Turner and Edwards syn-dromes. Presentation is the onset of regurgitation and vomiting in week 2 of life; waves of peristalsis are visible on the abdomen and there is a palpable oval abdomi-nal mass. Treatment is surgical.   Congenital diaphragmatic hernia   occurs when a congenital defect is present in the   diaphragm, resulting in herniation of the abdominal organs into the thoracic cav-ity. The stomach is the most commonly herniated organ due to left-sided congenital diaphragmatic hernia. Congenital diaphragmatic hernia is often associated with intestinal malrotation. It may be complicated by significant lung hypoplasia.     Hypertrophic Gastropathy   Ménétrier disease  is a rare ...

  Mechanical Obstruction Volvulus is a twisting of a segment of bowel on its vascular mesentery, causing intestinal obstruction and infarction. It is often associated with congenital abnormalities such as intestinal malrotation. Common locations include the sigmoid colon and small bowel; complications include infarction and peritonitis. Intussusception is the telescoping of a proximal segment of the bowel into the distal segment. It is most common in infants and children. Children present with vomiting, abdominal pain, passage of blood per rectum, and lethargy; a sausage-shapedmass is often palpable in the right hypochondrium.   In adults, intussusception may be caused by a mass or tumor. The intussusceptedsegment can become infarcted. Incarcerated hernia is a segment of bowel that is imprisoned within a hernia; the condition can become complicated by intestinal obstruction and infarction. Hirschsprung disease  (or congenital aganglionic megacolon) is caused by congenital...