What are the key clinical features to consider when diagnosing Duchenne Muscular Dystrophy in a child?

Key clinical features to consider when diagnosing Duchenne Muscular Dystrophy (DMD) in a child include:

• Progressive proximal muscle weakness, typically presenting in early childhood, often between ages 2 and 5 years, with difficulty in activities such as running, climbing stairs, or rising from the floor (Gowers' sign).
• Delayed motor milestones and frequent falls are common early indicators.
• Calf pseudohypertrophy due to muscle tissue being replaced by fat and connective tissue is a characteristic physical finding.
• Enlarged calf muscles and lumbar lordosis may be observed on examination.
• Elevated serum creatine kinase (CK) levels are a biochemical hallmark, often markedly raised even before clinical symptoms become apparent.
• Cardiac involvement may be present early, with electrocardiographic abnormalities such as conduction defects and arrhythmias, necessitating cardiac evaluation as part of diagnosis and ongoing management.
• Respiratory muscle weakness can develop as the disease progresses, although this is more relevant in later stages.
• Cognitive impairment or learning difficulties may be present in some children, reflecting the multisystem nature of the disease.

These features combined with a family history of DMD or a known dystrophin gene mutation support the diagnosis. Genetic testing confirming dystrophin gene mutations is definitive. Early recognition of these clinical signs is critical for timely referral and management ¹ (Yiu and Kornberg, 2008; Annexstad et al., 2014; Tang et al., 2022).