QUANTITATIVE HISTOLOGY OF NERVE IN PROTEIN‐CALORIE MALNUTRITION AND WELL‐NOURISHED CHILDREN*

Abstract

Dastur D.K., Dewan A., Manghani D.K. & Udani P.M. (1977) Neuropathology Applied Neurobiology 3, 405–422Quantitative histology of nerve in protein‐calorie malnutrition and well‐nourished childrenQuantitative histological data is presented on the sural nerve from four well‐nourished control children between the ages of 5 months and 10 years. The average myelinated nerve fibre density was 14 460/mm2 with a range of 13 020/mm2 to 15 700/mm2, and bore no relation to chronological age, both the oldest and the youngest, children showing high counts. An age‐related increase in size of myelinated fibres was seen in the histograms to become bimodal at age 1 year and then remained essentially unchanged until 10 years. One well‐nourished 9‐month‐old infant born 2 months preterm showed features suggesting retardation in myelination and nerve fibre growth, medium‐sized nerve fibres (> 5μm) having not yet developed, while the fibre density was greater (17 420/mm2). Quantitative histological data on the sural nerve is also presented in 8 of 14 children with protein‐calorie malnutrition (PCM), varying in age from 1.5 to 9 years, either with protein deficiency (kwashiorkor) predominating or with calorie malnutrition predominating. The majority had acquired some secondary infection as well. Twelve of the fourteen children suffered from severe malnutrition or marasmus (grade III or IV according to Harvard standards). The myelinated nerve fibre densities varied from 7940 to 22 820/mmz with a mean of 16 199/mm2, not significantly different from the mean densities in the four comparable control children. The histograms, however, showed a persistence of small diameter fibres (<5 μm) in children with PCM especially those above 2 years of age, suggesting an arrest of, or delay in, myelination. This arrest, and the frequent paucity of thick axons in silver stained preparations, suggested a lack of development of medium and large myelinated nerve fibres. There was also an inverse relationship betweeen the size of myelinated fibres and the grade of malnutrition as also the age of the patients.