Differential Diagnosis for 84-year-old Male Patient

Single Most Likely Diagnosis

• Acute Coronary Syndrome (ACS): Although the EKG is unremarkable, the elevated Troponin-I level is highly suggestive of myocardial injury, which is a key indicator of ACS. The patient's age and symptoms of chest pain also support this diagnosis.

Other Likely Diagnoses

• Gastroesophageal Reflux Disease (GERD) or Peptic Ulcer Disease: The patient's complaint of bilateral lower chest pain could be referred pain from the upper abdomen, suggesting a gastrointestinal cause. The normal EKG and elevated AST could also support this diagnosis, as AST can be elevated in liver disease or muscle injury, but can also be seen in other conditions.
• Pulmonary Embolism (PE): Although less likely given the lack of specific symptoms such as shortness of breath or tachypnea, PE should be considered, especially in an elderly patient with possible underlying risk factors.
• Musculoskeletal Pain: The patient's age and the nature of the pain could suggest a musculoskeletal origin, such as costochondritis or musculoskeletal strain.

Do Not Miss Diagnoses

• Aortic Dissection: This is a life-threatening condition that requires immediate diagnosis and treatment. Although the patient's symptoms do not specifically suggest aortic dissection (e.g., tearing chest pain), it is a diagnosis that cannot be missed due to its high mortality rate.
• Pneumonia: Especially in an elderly patient, pneumonia can present atypically, without the usual symptoms of cough or fever. The elevated BUN and creatinine could indicate dehydration or sepsis, which could be related to pneumonia.
• Cardiac Tamponade: This condition, characterized by fluid accumulation in the pericardial sac, can cause chest pain and is a medical emergency. The elevated NT pro-BNP could suggest heart failure, which could be related to tamponade.

Rare Diagnoses

• Esophageal Rupture: Although rare, this condition can cause severe chest pain and is a medical emergency. The patient's symptoms and elevated AST could support this diagnosis, but it would be less likely without a clear history of vomiting or other suggestive symptoms.
• Hemorrhagic Pancreatitis: The patient's abdominal pain and elevated AST could suggest pancreatitis, although the lack of specific symptoms such as nausea or vomiting makes this diagnosis less likely.