Differential Diagnosis for Dark Brown Vomiting in a Young Type 1 Diabetes Man

Single Most Likely Diagnosis

• Diabetic Ketoacidosis (DKA): The presence of raised ketones in a Type 1 diabetes patient with dark brown vomiting is highly suggestive of DKA. The vomiting can be due to the metabolic acidosis and dehydration associated with DKA.

Other Likely Diagnoses

• Gastroenteritis: Although less likely given the context of raised ketones, gastroenteritis could cause vomiting and dehydration, potentially exacerbating diabetic control and leading to ketosis.
• Food Poisoning: Similar to gastroenteritis, food poisoning could lead to vomiting and potentially impact blood glucose control and ketone levels.

Do Not Miss Diagnoses

• Bleeding Peptic Ulcer: Dark brown vomiting (hematemesis) could indicate a bleeding peptic ulcer, which is a medical emergency. The presence of diabetes and potential use of antiplatelet agents or NSAIDs could increase the risk.
• Intestinal Obstruction: Although less common, intestinal obstruction could cause vomiting and should be considered, especially if there are other symptoms like abdominal pain or constipation.

Rare Diagnoses

• Zollinger-Ellison Syndrome: A rare condition characterized by excessive gastric acid production leading to peptic ulcers and diarrhea, which could potentially cause dark brown vomiting if there is bleeding.
• Gastroparesis: A complication of diabetes that affects the stomach muscles, causing delayed gastric emptying, which might lead to vomiting. However, the vomiting is typically not dark brown unless there is bleeding.