An autopsy case of recurrent pneumothorax and peliosis-like intrapulmonary hematoma with X-linked myotubular myopathy.

BACKGROUND: The typical non-muscle complications of long-surviving X-linked myotubular myopathy (XLMTM) include scoliosis, head deformity, macrocephaly, gastroesophageal reflux disease and peliosis hepatis. Recently, pulmonary blebs and recurrent pneumothorax have also been reported as uncommon complications, whereas no reports on autopsy cases have focused on lung lesions. CASE PRESENTATION: An 8-year-old boy with XLMTM presented recurrent pneumothorax requiring bleb resection and pleurodesis. He subsequently developed multiple pulmonary mass lesions. He died of hemorrhagic shock due to peliosis hepatis. Autopsy showed multiple peliosis-like hematomas in the blebs of the lung. The histopathological examination of the hematomas revealed pooled blood without a pathway to bronchus. No apparent increase in desmin- or α-smooth muscle actin (α-SMA)-positive cells, namely myofibroblasts, was observed around hematomas, suggesting that the mutation in the myotubularin gene was involved in the defective repair process in the liver and lung tissues. CONCLUSION: Recurrent pneumothorax should be considered as a non-muscle complication of XLMTM. Peliosis-like intrapulmonary hematoma may also be a critical complication caused by poor proliferation of myofibroblasts in the tissue repair process.

Vitamin D deficiency associated with dilated cardiomyopathy in early infancy caused by maternal cholestasis.

Breast feeding is known to be a major cause of vitamin D deficiency in infants because the content of vitamin D in breast milk is significantly lower than that in formula. We report a case of a 1-mo-old boy who developed hypocalcemic seizures and dilated cardiomyopathy caused by vitamin D deficiency despite being fed a sufficient amount of regular formula. The cause of vitamin D deficiency in this case was maternal vitamin deficiency due to severe hyperemesis and insufficient sunlight exposure, induced mainly by the malabsorption of fat-soluble vitamins caused by maternal cholestasis. We should carefully consider maternal conditions during pregnancy and the postpartum period to detect and prevent vitamin D deficiency in the fetus and infant.