An adult case of midgut volvulus in familial visceral myopathy.

We report an adult case of midgut volvulus in familial visceral myopathy (FVM) that had affected family members over three generations. The patient was a Japanese woman in her fifties, who had chronic intestinal pseudo-obstruction (CIPO) since the age of about 40 years and had been treated chronically with conservative therapies. Her abdominal symptoms suddenly worsened and surgery became necessary. Surgery revealed a midgut volvulus secondary to intestinal malrotation and the twisted intestine was resected. Histology revealed diffuse damage of myocytes confined to the muscularis propria throughout the resected intestine. The myocytes were irregulary arranged, contained cytoplasmic inclusions, and had mild and focal vacuolar changes. The mucsularis propria showed hypertrophy with delicate interstitial fibrosis. A diagnosis of FVM was made on the basis of this characteristic myopathy. Intestinal malrotation is known to be a complication of CIPO in children, but is rare in adults. Although midgut volvulus appears to be extremely rare, it can occur after a relatively stable chronic phase in adult CIPO patients, who should be monitored carefully to assess the risk of such complications.