Prolactin concentrations during anaesthesia.

intestine is normal with no evidence of malabsorption." Three-day faecal fat excretion and xylose absorption test were normal. Although the serum B12 level was not available at the time, the evidence from blood, marrow, and barium meal examinations suggested vitamin B12 deficiency due to pernicious anaemia, and treatment was started with hydroxocobalamin 1 mg intramuscularly daily for four days, and then weekly. There was no haematological reponse, and the haemoglobin fell further to 34 %. The patient was then admitted to the Luton and Dunstable Hospital (under Dr B P Harrold), where folic acid was added to her treatment, again with no response in the peripheral blood or marrow. A blood transfusion brought her haemoglobin up to 10-8 g/dl, but a subsequent marrow aspiration confirmed the previous findings of a megaloblastic picture, with a few ring sideroblasts, insufficient to justify a diagnosis of sideroblastic anaemia. At the suggestion of the haematologist (Dr J R B Williams) a therapeutic trial of pyridoxine was begun with a dose of 50 mg twice a day. Seven days later the marrow had reverted to normal and the patient was discharged on pyridoxine alone. In the following weeks her haemoglobin gradually returned to normal levels. After the diagnosis had been established the serum B12 level, in a sample of blood taken at the start of the investigation and before the administration of hydroxocobalamin, was reported as normal at 360 ng/l. A Schilling test was also normal.