1 What are the most common malignant solid abdominal tumors in children? a. Neuroblastomas are derived from neural crest tissue. In the abdomen, they originate from the adrenal glands and parasympathetic ganglia. b. Wilms’ tumors, nephroblastomas, are derived from the…
1 What is the most common type of congenital diaphragmatic hernia (CDH)? Congenital abnormalities of the diaphragm include a posterolateral defect (Bochdalek hernia), an anteromedial defect (Morgagni hernia), or the eventration (central weakening) of the diaphragm. The Bochdalek hernia is…
1 What are tracheoesophageal fistula and esophageal atresia? The pathogenesis for the development of esophageal atresia, with and without fistula, is still unknown. Theories include imperfect separation of the tracheoesophageal septum or defective pharyngeal arch development. More than 50% of…
1 What is an anorectal malformation? Anorectal malformation is a term used to designate a series of congenital defects characterized by the absence of an anal opening. However, most of the time, the rectum is abnormally connected to the perineum…
1 What signs and symptoms suggest intestinal obstruction in the neonate? Signs and symptoms vary according to the location of the obstruction. Proximal intestinal obstruction leads to early bilious vomiting, typically with minimal distention. Neonates with distal intestinal obstruction often…
1 What is hypertrophic pyloric stenosis (HPS)? HPS is the most common cause of gastric outlet obstruction in infants resulting in nonbilious vomiting. The pathogenesis of HPS is unknown; it is not thought to be a developmental defect. Hypotheses include…
1 Why is the term dissecting aortic aneurysm really incorrect? The correct term should be dissecting aortic hematoma because the lesion is not an aneurysm. Blood passes into the media, creating a hematoma that separates the intima from the media…
1 Does lung cancer screening save lives? The United States National Lung Screening Trial (NLST) reported a reduction in lung cancer mortality of 20%, and a 6.7% decrease in all-cause mortality. Low-dose computed tomography (CT) scans may prove beneficial in…
1 Is lung cancer a single disease? Traditionally, lung cancer has been stratified histologically as squamous/epidermoid, adenocarcinoma, and small/large cell lung cancers. Our current ability to profile cancers at the molecular level appears to have both prognostic and therapeutic value.…
Pleural Effusion 1 What is a pleural effusion? Pleural fluid is generated in normal adults at a rate of 5–10 L per 24 hours in the combined hemithoraces, but normal adults have only 20 mL of pleural fluid present at…