Clinical and Experimental Dermatology 1991; 16: 53-54. ADONIS 0307693891000178 Ulceronecrotic lesions in a patient with essential thrombocythaemia J.A.VELASCO, J.C.SANTOS, J.BRAVO AND J.SANTANA Department of Dermatology, General University Hospital, Faculty of Medicine, Salamanca, Spain Accepted for publication \^ July 1990 Summary A 55-year-old woman is described wbo developed painful ulceration of a little toe as a manifestation of essential tbrombocvtbaemia. Of tbe so-called 'chronic myeloproHferative diseases', essential tbrombocythaemia {ET) is tbe most uncommon. It gives rise to two main complications: tbrombotic and haemorrbagic. The tbrombotic disturbances mainly affect the peripheral microcirculation. The elinieal manifesta- tions of iscbaemia due to occlusion are: inflammatory livedo lesions and/or ulceronecrotic lesions, mainly affecting the distal parts of tbe feet, wbicb are always accompanied by intense pain. Tbe clinical appearance of tbe lesions indicates a differential diagnosis of otber vascular processes leading to ischaemia and gangrene. Tbe uncommon appearance of this disease bas meant that little attention bas been paid to it in tbe dermatological literature. Case report Tbe patient was a female bospital worker aged 55. She complained of a tendency to bruising, occasional abdomi- nal pain, sbort periods of giddiness, occasional vomiting and migraine-like headacbes. In 1981, in a routine blood test a figure of 1200 x WjX platelets was ob.served. The ensuing investigation was concluded witb a diagnosis of ET (hyperplasia of tbe megakaryocyte series, tbe other series being normal). Initial treatment witb busulpban and ticlopidine lowered but failed to fully correct tbe platelet count. From 1983 onwards, treatment was continued witb bydroxyurea, wbicb afforded better results. In 1986, tbe patient was found to bave a gastric ulcer. In June 1989, she was sent to us from tbe baematology department; for the previous montb she bad been suffering from an ulceronecrotic lesion 1 cm in size on tbe distal portion of tbe fifth toe of Correspondence: J.A.Velasco, Departamento de Dermatologia, I Iospital General Universitario, P" San Vicente s/n, Salamanca, Spain. Figure 1. Ulceronecrotic lesion ofthe distal portion ofthe fifth toe. the rigbt foot (Fig. 1). Tbe lesion was witbin a reddish- purple zone that extended along the whole of tbe toe and distal outer part of the foot and was extremely painful. The pieture was bigbly suggestive of ischaemic necrosis. Tbe patient reported that 6 montbs previously an ulcer, also painful, bad developed on tbe outer side of tbe back of tbe heel of tbe same foot, also witbin purplish skin. Tbis ulcer bad bealed in 2-3 months. .At the time of presenting to us the patient was not receiving any treatment; ber platelet count was 830 x lO'Vl- On recom- mencing treatment witb hydroxyurea, the ulcer rapidly began to improve, although the background purplisb component persisted. Ilistologica I findings Acanthosis at tbe edge of tbe ulcer was observed. In tbe dermis tbere were alterations corresponding to repair, i.e. new vessel formation, proliferation of fibroblasts and extravasation of erythrocytes. In tbe mid-dermis, under the ulcer, there was an arteriole totally occluded by a completely organized fibrin tbrombus. 53