A Pattern Recognition Approach to Myopathy

Muscle diseases present a significant diagnostic challenge due to their extreme etiological heterogeneity and the limited range of clinical symptoms they produce. While genetic testing has become a cornerstone of the diagnostic process, this paper emphasizes that a rigorous clinical assessment remains the primary tool for navigating the complexity of these disorders. Clinicians must carefully evaluate the onset, progression, and distribution of weakness, while also screening for extraskeletal manifestations that may indicate a multisystem proteinopathy or other systemic involvement.

Although genetic testing often replaces muscle biopsy for many inherited myopathies, the biopsy remains a vital tool for diagnosing acquired muscle diseases and clarifying the pathogenicity of variants of uncertain significance. Laboratory markers, such as creatine kinase, are useful but must be interpreted within the context of the patient's clinical presentation, as they can be normal in certain inflammatory or metabolic myopathies. The paper highlights that biochemical screening—such as plasma acylcarnitine profiles for lipid storage myopathies—can identify treatable conditions that might otherwise be misdiagnosed as chronic, untreatable muscle disorders.

Artificial intelligence and advanced imaging techniques, such as quantitative MRI and multispectral optoacoustic tomography, are increasingly being integrated into neuromuscular practice to optimize patient care and track disease progression. Furthermore, the field is rapidly evolving with the development of gene-editing therapies and novel immunotherapies for refractory myositis. These advancements underscore the importance of achieving a specific diagnosis, as it directly impacts a patient's eligibility for targeted treatments and helps prevent complications, such as cardiac events in patients with specific genetic variants.