Effect of Protein Calorie Malnutrition on Peripheral Nerves

Abstract

Forty-three children (aged 7 to 62 months) with protein calorie malnutrition (PCM) were studied; 13 had mild to moderate PCM and 30 severe PCM. A reduction of motor nerve conduction velocity and abnormalities of sensory conduction were present in both groups. The abnormality of motor nerve conduction was directly related to the severity of PCM and the presence of hypotonia and/or hyporeflexia. Sural nerve biopsies from both groups were studied for myelinated fibre density, fibre size spectrum, relationship of internodal length with diameter and qualitative light microscopic changes. The biopsies from children with mild to moderate PCM were characterized by a normal developmental change in myelinated fibres with an increasing proportion of medium and large size fibres, a transition from a unimodal to a bimodal distribution and an appropriate relationship of internodal length to fibre diameter. Evidence of mild segmental demyelination was observed in only one patient of this group. In contrast, in the biopsies from children with severe PCM, the normal developmental pattern for myelinated fibre size distribution was impaired with a persistence of small myelinated fibres, and there was a failure of internodal segments on large fibres to elongate with increase in age and significant segmental demyelination in about 50 per cent of cases. Retarded myelination and segmental demyelination probably form the morphological basis for impaired peripheral nerve function in PCM. Short internodes on large diameter fibres may also contribute to this effect.

Interrelationships of undernutrition and neurotoxicity: Food for thought and research attention

“…Nerve biopsies of 7-62 month-old children with severe (but not moderate) protein-calorie malnutrition showed retarded myelination, segmental demyelination and short internodes, but both groups had abnormal motor nerve conduction in proportion to the severity of malnourishment and the presence of hypotonia and/or hyporeflexia (Chopra et al, 1986). Reduced nerve conduction velocity, which is related to the diameter and intermodal length of the largest myelinated nerve fibers, was evident in the upper and/or lower extremities of children with kwashiorkor and marasmus, respectively (Kumar et al, 1977).…”

Myelin basic protein accumulation is impaired in a model of protein deficiency during development

“…Malnutrition in infancy and childhood affects brain growth and may result in low intelligence for age (Chopra et al 1986). Several laboratories have shown malnutrition to have significant adverse effects on the functional development of the brain, in association with retardation of morphological and biochemical maturation.…”

Protein malnourishment: A predisposing factor in acrylamide toxicity in pregnant rats

“…Humans living in developing countries have generally been found to suffer from various physiological and functional disorders due to vitamin and mineral deficiencies, undernutrition, and protein energy malnutrition (Chopra et al, 1986). The energy and protein requirement is significantly high during pregnancy to regulate the normal body functions of the host itself and to meet the requirements of the growing fetus, which is solely dependent on the mother.…”