Proximal myotonic myopathy, also known as PROMM or PROMM-like syndrome, is a rare genetic muscular disorder characterized by muscle stiffness and weakness, primarily in the muscles of the upper arms and thighs. The term "proximal" refers to the fact that the muscles affected are those closest to the center of the body, while "myotonic" refers to sustained muscle contractions or myotonia.
This condition is caused by a gene mutation on chromosome 3, specifically in the DMPK gene, which codes for a protein involved in muscle function. The mutation leads to abnormal expansion of a repetitive DNA sequence in the gene, resulting in impaired muscle function.
Individuals with proximal myotonic myopathy often experience muscle stiffness and weakness, making it difficult for them to perform normal daily activities such as getting up from a seated position, climbing stairs, or lifting objects. They may also have trouble releasing their grip on objects or experience muscle pain and cramps.
Other symptoms may include muscle wasting, difficulty swallowing, cataracts, heart abnormalities, and respiratory problems. The severity and progression of symptoms can vary widely among affected individuals, even within the same family.
Diagnosis of proximal myotonic myopathy typically involves a combination of clinical symptoms, genetic testing, electromyography (EMG), and muscle biopsies. While there is currently no cure for this condition, management focuses on symptom relief and improving quality of life through physical therapy, assistive devices, pain management, and respiratory support if necessary.
Overall, proximal myotonic myopathy is a rare genetic disorder characterized by muscle stiffness and weakness primarily affecting the proximal muscles. With proper management, individuals with PROMM can lead fulfilling lives.
