Acute Steroid Myopathy: a Highly Overlooked Entity

Background: Myopathy in patients being treated with corticosteroids is known primarily among chronically treated patients or in critically ill and mechanically ventilated patients receiving corticosteroids, often in high doses.

Aim: To highlight the entity of acute, early onset corticosteroid-treatment-associated myopathy and its characteristics.

Design And Methods: Reporting our experience with four patients and reviewing all published reports of myopathy developing ≤14 days of initiating corticosteroid-treatment.

Results: Acute corticosteroid myopathy (ASM) exists, though the syndrome appears to be rare. It is characterized by unpredictability and heterogeneity, sometimes developing within 1-3 days, after a single dose, which may not be high and administered by varied routes. Proximal limb muscle weakness is the most common form, but distal limb, bulbar and respiratory muscles may be involved. Steroid cessation often leads to improvement/resolution, but irreversibility may occur.

Conclusions: A high index of suspicion for the possibility of ASM is necessary to ensure drug discontinuation and recovery. This is particularly true since the entity is not widely recognized and its symptoms are often erroneously interpreted as due to the patient's underlying disease.