Vitamin B12 deficiency: unusual cause of jaundice in an adolescent.

Vitamin B12 deficiency in vegans is a known cause of megaloblastic anaemia. We report an adolescent girl who presented with jaundice and weight loss for 6 months secondary to vitamin B12 deficiency, leading to megaloblastic anaemia. Replacement with vitamin B12 reversed her symptoms, resulting in weight gain, and normalised her haemoglobin, red blood cell morphology, bilirubin levels and serum vitamin B12 levels.

Cytogenetics in nutritional megaloblastic anaemia: prolonged persistence of chromosomal abnormalities in lymphocytes after remission.

Chromosomal studies were performed in phytohaemagglutinin-stimulated cultures of lymphocytes and in bone marrow cells without culture from 115 patients with megaloblastic anaemia resulting from nutritional deficiency of folate and vitamin B12. Essentially similar chromosomal abnormalities were observed in the two cell lines. These were characterized by striking morphological aberrations such as elongation and despiralization (uncoiling or incomplete contraction), increased frequency of chromosome breakage and centromere spreading. Numerical abnormalities, chromatid exchanges and translocations were virtually absent. Autoradiographic studies of chromosomes after pulse-labelling with 3H-thymidine during the terminal 6 h of phytohaemagglutinin-stimulated lymphocyte cultures revealed a differential pattern of distribution of the radionucleotide in the chromosome of megaloblastic lymphocytes as compared to those from normal lymphocytes. Repeated chromosomal studies were done in 65 of these patients at various intervals after starting therapy with the deficient vitamins. After 48 h of therapy, chromosomal abnormalities were remarkably reduced in the bone marrow; but many of these morphological chromosomal changes (i.e. despiralization and breaks) persisted in the lymphocytes of a significant proportion of patients for variable periods up to 6-12 months after haematological remission resulting from therapy with the deficient vitamins. These abnormalities did not, however, persist after remission in those patients who had repeated episodes of infections.

Nutritional megaloblastic anaemia in a young woman.

A young Australian woman developed a severe nutritional megaloblastic anaemia due to poor intake of vitamin B12 and, possibly, of folic acid. Simple dietary advice resulted in an adequate intake of vitamin B12 and folic acid, and in maintenance of normal serum levels of both vitamins.