SUMMARY A 63-year-old woman presented with Raynaud's phenomenon and extensive cold-induced livedo reticularis. A skin biopsy showed no abnormality of the blood vessels but the blood contained high titres of a very unusual autoantibody against the M blood group, most active at low temperatures. An IgM cryoglobulin was detected, and anti-M activity was found in this fraction. Livedo reticularis may occur in a wide variety of diseases affecting the blood vessels of the skin or the theological properties of the blood (Champion, 1965;Copeman, 1975). We describe the case of a woman with Raynaud's phenomenon and severe and extensive livedo reticularis regularly induced by cold and abolished by warmth, in whom the only abnormality found was an unusual anti-M autoantibody most active at low temperatures.
Case historyA 63-year-old housewife was admitted to The London Hospital in May 1977 complaining of purplish discoloration of the limbs. Ten months before admission she developed severe intermittent cramping pain in the upper arms, which was worse at night; this lasted for about three months and then resolved. At about the same time as the pain she noticed purple mottling especially of the hands but also of the arms and legs. This was worse in the cold and disappeared completely when she was very warm. For six months before admission she had noticed Raynaud's phenomenon affecting the hands. Prednisolone, 10 mg daily, had been given for some weeks without benefit. She had had tuberculosis of the spine and rheumatic fever as a girl. She had had two miscarriages, and two live births with healthy infants. She had never had a blood transfusion. For some years before admission
INVESTIGATIONSHaemoglobin 9.5 g/dl, haematocrit 0-291, mean corpuscular volume 92 fl, mean corpuscular haemoglobin 30-3 pg, mean corpuscular haemoglobin concentration 32-4 g/dl. Anisocytosis, polychromasia, and agglutination of the red cells were noted, but unfortunately a reticulocyte count was not performed. The blood count was repeated three months later in warm weather and showed a haemoglobin of 12-8 g/dl and a reticulocyte count of 1-2 %. The white cells and platelets were normal. Serum total bilirubin 28 ,tmol/l (1 -6 mg/100 ml) direct 5 ,umol/l (0-3 mg/ 100 ml), liver function tests otherwise normal. A biopsy of affected skin showed no abnormality on histological or immunofluorescent examination; the blood vessels were normal. The following were also normal or negative: antinuclear factor and autoantibody screen, latex fixation test, plasma protein electrophoresis, serum iron, vitamin B12 and folate, red-cell folate, urea and electrolytes, Treponema pallidum, haemagglutination, and VDRL slide test, microscopy and culture of the urine, and x-rays of the chest, skull, and hands. X-ray of the lumbar 154 on 10 May 2018 by guest. Protected by copyright.