Idiosyncratic Agranulocytosis in Elderly Patients

Sixty-one patients were identified. One patient presented 2 episodes of IDIA (with 2 different drugs). All patients were Caucasian. The mean and median ages were 84.9 and 82 years (range, 75-95), respectively. The sex-ratio female/male was 2.4. Seventy-four percent of the patients (n=45) presented an underlying disease. Main families of causative drugs were: antibiotics (n=25, 43.8%), especially ß-lactams (n=16) and cotrimoxazole (n=9); antithyroid drugs (n=9, 15.8%); neuroleptic and anti-epileptic agents (n=7, 12.3%); and antiaggregative platelet agents (n=6, 10.5%), especially ticlopidine (n=5). There was only 1 case of self-medication. Discovery circumstances were (n=60): decrease in neutrophil blood counts (n=29, 48.3%); isolated fever (n=22, 36.7%); documented infections (n=8, 13.3%), as acute tonsillitis or pneumonia, with one case of septic shock. Clinical presentations during hospitalization were (n=58): isolated fever (fever of unknown origin) (n=16, 27.6%); documented pneumonia (n=12, 20.7%); septicemia (n=9, 15.5%); septic shock (n=5, 8.6%). The remaining symptomatic patients presented documented infections (n=14, 24.1%), as: acute pyelonephritis (n=4); sore throats and acute tonsillitis (n=4); cutaneous infections (n=1); cholecytitis (n=1); colitis (n=1); infectious spondylitis (n=1); endocarditis (n=1); and fever with deep venous thrombosis (n=1). Two patients (3.4%) remained asymptomatic during the hospitalization. During the hospitalization, 15 patients (25.9%) presented features of severe sepsis, septic shock and/or systemic inflammatory response syndrome (SIRS). Bacteriological documentation (n=54) was obtained in 23 cases (42.6%). At the time of discovery, the mean and median neutrophil counts were 1.62 and 1.5 × 109/L (range, 0.26-6.3). At nadir of the neutrophil decrease, mean and median neutrophil counts were 0.15 and 0.08 × 109/L (range, 0-0.4). Fifty-four percent of patients (n=33) had neutrophil levels of less than 0.1 × 109/L.