EFFECT OF AZTREONAM ON PLATELET AGGREGATION AND BLOOD COAGULATION IN ELDERLY PATIENTS

• Published in: CHEMOTHERAPY Vol. 39; no. 3; pp. 247 - 252
• Main Authors: Mase, Kanshi, Yamanaka, Yoshitaka, Yasunaga, Kojiro, Yamano, Masahiro, Yoshioka, Muneto, Asada, Takahiro, Soga, Tetsuji, Yanagihara, Futoshi
• Format: Journal Article
• Language: Japanese
• Published: Japanese Society of Chemotherapy 1991; 公益社団法人 日本化学療法学会
• Subjects: aztreonam; ビタミンK; 血小板凝集能; 血液凝固能; 高齢者
• ISSN: 0009-3165; 1884-5894
• DOI: 10.11250/chemotherapy1953.39.247

In recent years, there have been reports of hemorrhagic manifestations as a effect of antibiotics. In this connection, we evaluated the effects of the first monobactam antibiotic, aztreonam, (AZT) on platelet aggregation and blood coagulation in elderly patients. The subjects were 9 patients: 4 with pneumonia, 1 with bronchitis, 2 with urinary tract infection and 2 with infected decubitus, aged from 65 to 85 years. AZT was administered by drip infusion at a dose of 2 or 4g/day for 5 to 10 days. The following parameters were measured before and after administration: platelet count, platelet aggregation, prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (Fbg), thrombotest (TT), and protein induced by vitamin K absence-II (PIVKA-II). There was no significant change in the platelet count or the blood coagulational parameters (PT, APTT, Fbg, TT and PIVKA-II) after AZT administration. AZT slightly suppressed ADP-induced platelet aggregation, but the suppression was clinically not problematic and there were no hemorrhagic manifestations. However, an increase in AZT concentration in plasma was suspected in a case of renal hypofunction in which blood urea nitrogen and creatinine had deteriorated and suppression of platelet aggregation had increased after AZT administration. We concluded that AZT hardly affects platelet aggregation and blood coagulation in therapeutic doses in elderly patients. Nevertheless, AZT must administered with care to elderly patients because they are liable to have hemorrhagic manifestations if AZT concentration in plasma increases because of renal hypofunction and because they tend to lack vitamin K because of decreased food intake.