Differential Diagnosis for Abdominal Pain and Emesis

The patient presents with abdominal pain, emesis, chest pain, shortness of breath, and diarrhea. Here is a categorized differential diagnosis:

• Single Most Likely Diagnosis

  • Gastroenteritis: This is likely due to the acute onset of symptoms, including abdominal pain, emesis, and diarrhea, especially after consuming a potentially irritating food like pizza. The lack of blood or bile in the vomit and the absence of significant improvement with Zofran also point towards a gastrointestinal infection rather than a more severe condition like an obstruction or ulcer.

• Other Likely Diagnoses

  • Acute Appendicitis: Although the pain is described as sharp and in the lower abdomen, which could suggest appendicitis, the presence of emesis and diarrhea, along with the recent consumption of pizza, makes gastroenteritis more likely. However, appendicitis cannot be ruled out without further evaluation.
  • Food Poisoning: Given the onset of symptoms after eating pizza, food poisoning is a plausible diagnosis. The symptoms of abdominal pain, emesis, and diarrhea are consistent with this condition.
  • Viral Gastroenteritis (e.g., Norovirus): This could explain the sudden onset of symptoms, including emesis, diarrhea, and abdominal pain, especially if the patient was exposed to someone with similar symptoms or consumed contaminated food.

• Do Not Miss Diagnoses

  • Bowel Obstruction: Although less likely given the acute onset and the nature of the symptoms, a bowel obstruction could present with severe abdominal pain, emesis, and an inability to pass gas or have bowel movements. The fact that Zofran did not help and the presence of chest pain and shortness of breath (which could be related to severe vomiting but also to other serious conditions) necessitates consideration of this diagnosis.
  • Mesenteric Ischemia: This is a serious condition that could present with severe abdominal pain out of proportion to the physical examination findings, along with emesis. The chest pain and shortness of breath could be related to the stress of the condition or associated cardiac issues.
  • Ectopic Pregnancy: In a female patient of childbearing age, ectopic pregnancy must be considered, especially with lower abdominal pain and emesis. However, the presence of diarrhea and the specific context of eating pizza might make this less likely.
  • Pulmonary Embolism: The chest pain and shortness of breath could suggest a pulmonary embolism, especially if the vomiting is severe enough to cause dehydration and subsequently lead to a hypercoagulable state.

• Rare Diagnoses

  • Intussusception: This condition, where a part of the intestine telescopes into another, can cause abdominal pain, emesis, and sometimes diarrhea. It's more common in children but can occur in adults, often with a lead point like a tumor.
  • Superior Mesenteric Artery Syndrome: This rare condition involves compression of the duodenum between the abdominal aorta and the superior mesenteric artery, leading to obstruction. Symptoms can include abdominal pain, emesis, and an inability to eat.
  • Diabetic Ketoacidosis (DKA): Although more commonly associated with hyperglycemia and ketosis, DKA can present with abdominal pain, emesis, and shortness of breath. The presence of diarrhea might be less typical but could occur due to the metabolic derangements.