Hereditary myopathy with early respiratory failure

Area of Science:

• Neurology
• Genetics
• Pulmonology

Background:

• Neuromuscular diseases can manifest as acute respiratory failure without preceding symptoms.
• Adult-onset respiratory failure necessitates a broad differential diagnosis.

Purpose of the Study:

• To report a case of a novel mutation in the TTN gene causing hereditary myopathy with early respiratory failure (HMERF).
• To highlight the importance of considering HMERF in adults with unexplained respiratory failure.

Main Methods:

• Clinical presentation and examination findings of a 30-year-old woman with progressive dyspnea.
• Diagnostic workup including MRI of muscles, muscle biopsy, and genetic testing.
• Identification of a novel heterozygous missense mutation in the TTN gene.

Main Results:

• The patient presented with acute respiratory failure requiring non-invasive ventilation and exhibited proximal and distal muscle weakness with scapular winging.
• Muscle imaging revealed selective fatty replacement, and biopsy showed rimmed vacuoles, core-like structures, and desmin aggregates.
• Genetic analysis identified a novel TTN gene mutation (c.95350G>A, p.Ala31784Thr), confirming the diagnosis of HMERF.

Conclusions:

• HMERF is a potential cause of acute respiratory failure in adults.
• Early recognition and genetic testing for TTN mutations are vital for diagnosing HMERF in patients with unexplained respiratory failure.