ULTRASTRUCTURE OF VOLUNTARY MUSCLE IN CHILDHOOD MALNUTRITION

This paper is part of a study on the electron microscopy of protein-en ergy malnutrition using a rapid autopsy protocol. Samples of voluntary muscle, obtained from eight children dying of severe oedematous malnu trition, were fixed in glutaraldehyde within 75 minutes of death. Atro phy of myofibres, increased prominence of satellite cells, and segment al necrobiosis were seen by light microscopy. Electron microscopy show ed variable depletion of myofibrils. In the most severe case, there wa s focal absence of myofibrils, also disorganized Z lines, and absent M bands. Residual atrophic myofibrils measured less than 0.1 mu m in wi dth. Other specimens showed sarcomere disorganization, mitochondrial s welling, glycogen depletion, sarcoplasmic oedema, and focal contractio ns of sarcomeres. Though non-specific, rigor may be accelerated by fre e radical damage, calcium release into the cytosol, and low supplies o f high-energy phosphates. These conditions may exist in severe malnutr ition, complicated by terminal infection and metabolic disturbances.