Differential Diagnosis
The patient's symptoms of a drop in saturation on standing, hepatomegaly, cardiomegaly with contrast infused into hepatic veins, and concerns for COPD suggest a complex clinical picture involving the cardiovascular and respiratory systems. Here's a categorized differential diagnosis:
Single Most Likely Diagnosis
- Hepatopulmonary Syndrome (HPS): This condition is characterized by a triad of liver disease (often suggested by hepatomegaly), intrapulmonary vascular dilatations (which could explain the drop in saturation upon standing due to increased shunting), and impaired oxygenation. The presence of hepatomegaly and the specific finding of contrast infusion into hepatic veins indicating possible intrapulmonary shunting make HPS a strong consideration.
Other Likely Diagnoses
- Chronic Thromboembolic Pulmonary Hypertension (CTEPH): This condition could explain the cardiomegaly (due to right heart strain) and the drop in saturation. Hepatomegaly could be secondary to right heart failure.
- Portopulmonary Hypertension (POPH): A condition that combines liver disease with pulmonary hypertension, which could explain the hepatomegaly, cardiomegaly, and desaturation on standing.
- COPD with Secondary Pulmonary Hypertension: Given the concerns for COPD, if the patient has significant pulmonary hypertension, it could lead to right heart failure (explaining cardiomegaly and hepatomegaly) and desaturation.
Do Not Miss Diagnoses
- Pulmonary Embolism (PE): Although less likely given the chronic nature of the symptoms, a large or multiple PEs could cause acute desaturation, cardiomegaly due to strain, and potentially hepatomegaly if there's associated right heart failure.
- Hepatic Venous Outflow Obstruction: Conditions like Budd-Chiari syndrome could cause hepatomegaly and potentially lead to desaturation if there's significant impact on cardiac function or if there are associated pulmonary complications.
Rare Diagnoses
- Osler-Weber-Rendu Syndrome (Hereditary Hemorrhagic Telangiectasia): A rare genetic disorder that could lead to arteriovenous malformations in the liver and lungs, potentially explaining the hepatomegaly, cardiomegaly, and desaturation.
- Congenital Hepatic Fibrosis: A rare condition that could lead to hepatomegaly and portal hypertension, potentially associated with pulmonary abnormalities leading to desaturation.
Each of these diagnoses requires careful consideration of the patient's full clinical picture, including laboratory results, imaging studies, and physical examination findings to determine the most appropriate diagnosis and treatment plan.