Scanning electron microscopy of the jejunum in children with protein-energy malnutrition

RESUMO

Samples of jejunum from seven children dying from severe oedematous malnutrition were fixed with intralumenal glutaraldehyde in combination with external immersion, using a rapid autopsy protocol. Selected areas were post-fixed in osmium tetroxide, dehydrated with an ethanol series and critical point dried. After mounting on aluminium stubs, specimens were sputter-coated with a thin layer of gold and palladium. Scanning electron microscopy showed patterns ranging from subtotal villous atrophy, through partial villous atrophy with low ridges, to longer, taller ridges with cerebriform convolutions. In one case, villous height had been interpreted as normal on light microscopy. The scanning electron microscope revealed that the mucosa in this case was composed of ridges and leaf forms. Processing for scanning electron microscopy is simple. The specimens can be viewed and photographed in a relatively short time. In addition, the three-dimensional record provides clarification of ambiguities which often arise from routine histological sections.