Differential Diagnosis for 18M with Nausea and Vomiting

Single Most Likely Diagnosis

• Cyclic Vomiting Syndrome (CVS): This condition is characterized by recurrent, severe episodes of vomiting that are separated by periods of normal health. The cyclic pattern of symptoms, feeling better after vomiting, and lack of abdominal pain or cramps are consistent with CVS. The patient's history of previous eating disorders and depression may also contribute to the development of CVS.

Other Likely Diagnoses

• Gastroparesis: Delayed gastric emptying can cause nausea and vomiting, especially after eating. The patient's history of eating disorders and significant weight fluctuations may have contributed to gastroparesis.
• Functional Dyspepsia: This condition is characterized by recurrent upper abdominal symptoms, including nausea and vomiting, without an identifiable cause. The patient's symptoms of nausea and vomiting without abdominal pain or cramps are consistent with functional dyspepsia.
• Nutritional Deficiency: The patient's history of eating disorders and significant weight fluctuations may have led to nutritional deficiencies, which can cause nausea and vomiting.

Do Not Miss Diagnoses

• Coeliac Disease: Although the patient has tried a dairy-free diet without improvement, coeliac disease is an important diagnosis to consider, especially given the patient's symptoms of nausea and vomiting. Coeliac serology has been ordered to rule out this condition.
• Gastrointestinal Obstruction: Although the patient's symptoms are cyclic and do not suggest an acute obstruction, a partial or intermittent obstruction could cause similar symptoms.
• Inflammatory Bowel Disease: Conditions such as Crohn's disease or ulcerative colitis can cause nausea and vomiting, especially if the disease is affecting the upper GI tract.

Rare Diagnoses

• Mitochondrial Neurogastrointestinal Encephalomyopathy (MNGIE): This rare genetic disorder can cause gastrointestinal symptoms, including nausea and vomiting, as well as neurologic symptoms.
• Eosinophilic Gastroenteritis: This rare condition is characterized by eosinophilic infiltration of the gastrointestinal tract, which can cause nausea and vomiting, as well as abdominal pain and diarrhea.
• Cannabinoid Hyperemesis Syndrome: Although the patient denies recreational drug use, this condition is characterized by recurrent episodes of severe vomiting, often triggered by cannabis use.