RESUMO
Two cases of anticoagulant-induced platelet-white blood cell aggregation are described, which resulted in erroneous haemocytometry counts. Aggregation was avoided by the use of acid citrate dextrose (ACD) as an auxiliary anticoagulant, thus enabling quantification of platelets and white blood cells.
Assuntos
Anticoagulantes/farmacologia , Contagem de Células Sanguíneas/efeitos dos fármacos , Agregação Celular/efeitos dos fármacos , Ácido Cítrico , Glucose/análogos & derivados , Agregação Plaquetária/efeitos dos fármacos , Ácido Edético/farmacologia , Glucose/farmacologia , Humanos , Contagem de Leucócitos/efeitos dos fármacos , Leucócitos/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Contagem de Plaquetas/efeitos dos fármacosRESUMO
Udenfriend's (Sjoerdsma A, Weissbach H, Udenfriend S. J Am Med Assoc 1955; 159: 397) classical screening method for urinary 5-hydroxyindole-3-acetic acid (5-HIAA) is known to be subject to error due to food and drug interferences. Goldenberg (Goldenberg H. Clin Chem 1973; 19: 38-44) introduced a more specific and sensitive method, which has recently been modified by Zouheir Habbal (Zouheir Habbal M. Clin Chim Acta 1983; 130: 251-256). The latter method is shown to correlate fairly well with a high-pressure liquid chromatography (HPLC) method in the 0-100 mumol/24 h range (reference values up to 34 mumol/24 h). It is suggested that elevated values in Udenfriend's screening method can be reliably checked by applying either method.
