Elevation of creatine kinase in acute severe asthma is not of cardiac origin

Objective: To study prospectively if, when plasma creatine kinase (CK) and plasma myoglobin are elevated, the origin of these abnormalities is cardiac or not, by measuring cardio-specific troponin T (cTT). Method: Fifteen patients with acute severe bronchial asthma (ASBA) were pro spectively studied in the intensive care unit (ICU) with continuous electro cardiograph (ECG). Plasma CK, CK-MB, myoglobin and cTT were measured at 0, 4, 8, 12, 16 and 20 h in the ICU. Results: Five out of 15 ASBA patients had elevated CK, four of them present ing with an increase in CKMB. Plasma cTT was normal in every patient, inclu ding those with CK and/or myoglobin elevation. At admission to the ICU, myo globin and CK were positively correlated (r = 0.760; p < 0.001). No patient was intubated. There was no difference in clinical signs or symptoms, medi cal history, laboratory values or ECC in patients with or without CK elevat ion. Conclusion: Patients admitted to an ICU for ASBA may present with an elevat ion of plasma CK, CK-MB and myoglobin not related to any heart injury. CK a nd CK-MB are not good markers of myocardial injury in ASBA patients due to the multitude of potential confounders. Therefore, troponin should be measu red instead.