Differential Diagnosis for Elevated CK and CKMB

Single Most Likely Diagnosis

• Acute Myocardial Infarction (AMI): Elevated CKMB is highly specific for myocardial damage, and when combined with elevated CK, it strongly suggests AMI. CKMB is a more specific indicator of heart muscle damage compared to CK.

Other Likely Diagnoses

• Myopericarditis: Inflammation of the heart muscle and the surrounding sac (pericardium) can lead to elevated CK and CKMB due to myocardial damage.
• Severe Musculoskeletal Injury: Significant muscle trauma can elevate CK levels, and if the injury involves the heart or is severe enough, CKMB might also be elevated.
• Intensive Muscle Exercise: Prolonged or intense physical activity can cause muscle damage, leading to elevated CK levels. However, CKMB elevation is less common in this context.

Do Not Miss Diagnoses

• Pulmonary Embolism with Cardiac Strain: Although less common, a large pulmonary embolism can cause right heart strain, potentially leading to myocardial damage and elevation of CK and CKMB.
• Cardiac Contusion: Trauma to the chest can cause direct injury to the heart, resulting in elevated cardiac enzymes.
• Aortic Dissection: This condition involves a tear in the aorta's inner layer and can cause myocardial damage if it compromises coronary blood flow, leading to elevated CK and CKMB.

Rare Diagnoses

• Hypothyroidism: Severe, untreated hypothyroidism can lead to muscle damage and elevated CK levels, though CKMB elevation is less common.
• Muscular Dystrophies: Certain muscular dystrophies can cause chronic muscle damage, potentially elevating CK levels. However, CKMB elevation would be unusual in these conditions.
• Neuroleptic Malignant Syndrome: A rare but life-threatening neurological disorder that can cause muscle damage and elevate CK levels. CKMB elevation might occur but is less characteristic.