Adverse Haematological Effects of Ticlopidine A Report of Four Cases M. Gallerani, 1 R. Manfredini, 2 P. Donegà, 1 F. Lanza, 3 M. Da Busti, 3 G.B. Vigna 1 and R. Fellin 1 1 Department of Clinical and Experimental Medicine, Section of Internal Medicine II, University of Ferrara, Ferrara, Italy 2 Department of Clinical and Experimental Medicine, Section of Internal Medicine I, University of Ferrara, Ferrara, Italy 3 Department of Biomedical Science and Advanced Therapies, Section of Hematology, University of Ferrara, Ferrara, Italy CASE REPORTS Clin Drug Invest 2000 Mar; 19 (3): 231-237 1173-2563/00/0003-0231/$20.00/0 © Adis International Limited. All rights reserved. Ticlopidine is an antiplatelet agent widely used to reduce the occurrence of atherothrombotic arterial events. [1] In various trials it was effective in preventing stroke, [2-5] peripheral arterial dis- ease, [6,7] myocardial infarction and angina, [8-12] or death caused by vascular events. [13,14] The most frequently reported adverse effects are diarrhoea, nausea, vomiting and abdominal cramps [13] and, occasionally, hepatotoxicity. [15-18] Moreover, in some of the major trials ticlopidine has been asso- ciated with neutropenia and, in subsequent case reports, with aplastic anaemia, thrombocytopenia and thrombotic thrombocytopenic purpura (TTP), [16,19-31] which have been fatal in some instances. [32,33] In this report we present four patients with cardiovascular or cerebrovascular disease who were admitted for severe pancytopenia or thrombo- cytopenia associated with ticlopidine therapy. Case Reports Case Report 1 A 65-year-old man was admitted to hospital for onset of fever. His medical history showed bronchial asthma, and 2 months previously he had presented with effort angina and therapy with ticlopidine had been started. At that time, blood chemistry and complete blood count values were normal. The cause of admission was the onset, a week before, of a constant evening fever (38.5 to 39°C) associated with severe pharyngodynia, dysphagia and vomiting. He denied any alcohol or cigarette consumption. At the time of examination he was taking amoxicillin 2 g/day, intramuscular cefonicid 1 g/day, ticlopidine 500 mg/day, diltiazem 240 mg/day and bamifylline 1200 mg/day. At the first clinical examination, the patient was conscious and compliant; pulse, blood pressure, respiration rate and axillary temperature were 84 beats/min, 140/80mm Hg, 34 breaths/min and 38.6°C, respectively. A chest examination found thoracic whistles, both tongue and pharynx showed the presence of muguet, and neither tonsillar plaques nor laterocervical, subaxillary or inguinal lymph nodes were found. Blood count showed white blood cells (WBC) 1100 × 10 6 /L, neutrophils 3.2% (35 × 10 6 /L), lymphocytes 80.4% (884 × 10 6 /L), monocytes 15.9% (175 × 10 6 /L), eosino- phils 0.3% (3.3 × 10 6 /L), basophils 0.2% (2.2 × 10 6 /L), haemoglobin (Hb) 129 g/L, haematocrit