Navigating gastrointestinal challenges in genetic myopathies: Diagnostic insights and future directions

Table 5 Mechanism of gastrointestinal manifestations in genetic myopathies

Mechanism	Description
Smooth muscle dysfunction	Genetic mutations affecting smooth muscle cells can lead to contraction, coordination, and relaxation abnormalities, resulting in dysphagia, gastroesophageal reflux disease, gastroparesis, bloating, abdominal pain, constipation, diarrhea, and intestinal pseudo-obstruction
Skeletal muscle abnormalities	Dysfunction in skeletal muscles involved in voluntary control of the GI tract, such as pelvic floor muscles and the external anal sphincter, can cause fecal incontinence and difficulty with bowel movements. Weak abdominal muscles can hinder effective stool pushing during defecation. Weak masticatory muscles can lead to difficulty chewing and swallowing
Smooth muscle innervation and neuromuscular transmission	Genetic mutations can affect smooth muscle innervation and disrupt neuromuscular transmission in the enteric nervous system, leading to dysregulation of smooth muscle activity and symptoms such as diarrhea or constipation
Abnormal regulatory pathways	Disruption of neurotransmitters, hormones, and signaling pathways that regulate smooth muscle cells in the GI tract can result in abnormal smooth muscle contraction and relaxation patterns, contributing to GI symptoms
Systemic manifestations	Genetic myopathies can be associated with systemic abnormalities, such as metabolic disturbances and endocrine dysfunction, which indirectly impact the GI tract and contribute to GI symptoms, including impaired gut motility and nutrient absorption
Malabsorption	Chronic GI problems in genetic myopathies can lead to malabsorption of essential nutrients, resulting in deficiencies of vitamins, minerals, and electrolytes, which further impact overall health and exacerbate symptoms

GI: Gastrointestinal.