Recurrent spontaneous small bowel perforations with a rare pathology: non-familial visceral myopathy

Visceral myopathy is a rare, often misdiagnosed disease characterised by abnormalities in the gastrointestinal smooth muscle layer. Its clinical presentation includes pseudo-obstruction, intestinal dysmotility and spontaneous perforation. We report an atypical case of a 51-year-old man with a history of recurrent small bowel perforations who presented with an acute abdomen. A laparotomy was performed with identification of a distal jejunal perforation. A small bowel resection with end-to-end anastomosis was done. Minimal adhesions were seen intraoperatively despite the patient’s multiple prior surgeries. Pathology showed histiocytic inflammation and patchy loss of the muscle layer reflective of visceral myopathy. Genetic testing revealed a variant of uncertain significance in the myosin light chain kinase gene. It is difficult to make a conclusive diagnosis given the patient’s clinical presentation closely mimicking other gastrointestinal disorders. However, it is crucial to consider visceral myopathy in patients with recurrent spontaneous intestinal perforations as a differential diagnosis.

Visceral Myopathy: Clinical syndromes, genetics, pathophysiology, and Fall of the Cytoskeleton

Visceral smooth muscle is a crucial component of the walls of hollow organs like the gut, bladder, and uterus. This specialized smooth muscle has unique properties that distinguish it from other muscle types and that facilitate robust dilation and contraction. Visceral myopathies are diseases where severe visceral smooth muscle dysfunction prevents efficient movement of air and nutrients though the bowel, impairs bladder emptying, and affects normal uterine contraction and relaxation, particularly during pregnancy. Disease severity exists along a spectrum. The most debilitating defects cause highly dysfunctional bowel, reduced intrauterine colon growth (microcolon), and bladder emptying defects requiring catheterization, a condition called Megacystis Microcolon Intestinal Hypoperistalsis Syndrome (MMIHS). People with MMIHS often die early in childhood. When the bowel is the main organ affected and microcolon is absent, the condition is known as myopathic chronic intestinal pseudo-obstruction (CIPO). Visceral myopathies like MMIHS and myopathic CIPO are most commonly caused by mutations in contractile apparatus cytoskeletal proteins. Here, we review visceral myopathy-causing mutations and normal functions of these disease-associated proteins. We propose molecular, cellular, and tissue-level models that may explain clinical and histopathological features of visceral myopathy and hope these observations prompt new mechanistic studies.

Hollow Visceral Myopathy, a Rare Gastrointestinal Disorder: A Case Report and Short Review

Hollow visceral myopathy (HVM) is described as impaired intestinal function and motility in the absence of mechanical obstruction. In this case report, we describe a unique case of an 18-year-old female who presented to the hospital with complaints of persistent nausea, vomiting, inability to tolerate oral feeds, and substantial weight loss for 2 months. After appropriate investigations, a diagnosis of gastroparesis was established. The patient was started on metoclopramide, which led to significant symptomatic improvement, and she was eventually discharged home. One month after discharge, she presented to the hospital with symptoms similar to her initial presentation. After further laboratory and radiological investigation, she was diagnosed with severe gastroparesis and chronic intestinal pseudo-obstruction. Over the next month, the patient was given an extensive trial of multiple prokinetic agents such as mirtazapine, ondansetron, pyridostigmine, octreotide, and promethazine, but she failed to show clinical improvement. Due to failure of medical therapy, a nasojejunal feeding tube was placed for enteral nutrition. However, the patient reported worsening of her symptoms despite slow feeding rates; hence, a decision was made to start the patient on total parenteral nutrition and transfer her to a larger tertiary center for higher level of care. At the tertiary hospital, the patient was continued on total parenteral nutrition and underwent extensive evaluation. Ultimately, she was diagnosed with HVM after a laparoscopic full-thickness intestinal biopsy showed histopathological evidence of the disease. She underwent isolated small intestine transplant, which led to significant improvement of her symptoms and was eventually discharged home. The patient continues to be symptom-free and follows up with Gastroenterology and Transplant Surgery regularly. This case report highlights a rare clinical condition, HVM, as a potential diagnosis in patients with clinical features of intestinal obstruction without mechanical obstruction.