Differential Diagnosis for 16-year-old Male with Abdominal Pain and Severe Vomiting

• Single most likely diagnosis:

  • Cyclical Vomiting Syndrome (CVS): This condition is characterized by recurrent, severe episodes of vomiting that are often relieved by hot showers, as seen in this patient. The lack of response to OTC antiemetics and the specific relief from hot showers are key clues pointing towards CVS.

• Other Likely diagnoses:

  • Gastroesophageal reflux disease (GERD): Although GERD typically presents with heartburn and regurgitation, severe cases can lead to vomiting. The abdominal pain and vomiting could be consistent with GERD, especially if the patient has triggers such as certain foods or lying down after eating.
  • Peptic ulcer disease: This condition can cause abdominal pain and vomiting, especially if the ulcer is perforated or if there is significant bleeding. However, the relief with hot showers is not typical for peptic ulcer disease.
  • Inflammatory bowel disease (IBD): Conditions like Crohn's disease or ulcerative colitis can present with abdominal pain, vomiting, and changes in appetite or ability to eat. The severity of symptoms can vary, and while hot showers are not a known relieving factor, the other symptoms could fit.

• Do Not Miss diagnoses:

  • Appendicitis: Although the symptoms do not perfectly align (appendicitis typically presents with localized right lower quadrant pain), any condition causing severe abdominal pain and vomiting must be considered for appendicitis due to its potential for serious complications if not promptly treated.
  • Intestinal obstruction: This is a surgical emergency that can present with severe vomiting and abdominal pain. The lack of response to antiemetics and the severity of symptoms could suggest an obstruction, especially if there are signs of bowel ischemia or perforation.
  • Pancreatitis: Acute pancreatitis can cause severe abdominal pain and vomiting. While the relief with hot showers is not characteristic, pancreatitis is a condition that requires immediate medical attention due to potential complications.

• Rare diagnoses:

  • Porphyria: This group of disorders can cause acute intermittent porphyria, which presents with severe abdominal pain, vomiting, and sometimes neurological symptoms. The relief with hot showers is not typical, but the condition is rare and can be considered in cases where common diagnoses are ruled out.
  • Gastric volvulus: A rare condition where the stomach twists abnormally, leading to severe vomiting and abdominal pain. It's an emergency that requires surgical intervention and could be considered if other diagnoses are excluded.