RESUMO
The relation between the level or the quality of serum cholinesterase and susceptibility to succinylcholine-induced apnea is significant because the abnormality resides in a low affinity variant rather than in a quantitative deficiency. A population study was undertaken in Trinidad to determine the pattern of the cholinesterase phenotype, using quantitative biochemical tests and the dibucaine number. Of 1290 subjects, 567 were African, 418 were Indian, 237 were of mixed lineage, and 68 belonged to the minority races. The dibucaine number did not differ between races or sexes. Of the population, 98.5% had normal enzyme characteristics. Indians had the highest values for the dibucaine number and the enzyme activity. Cholinesterase was significantly higher in African and mixed males. The homozygous atypical gene was not detected, but the frequency of the heterozygous "atypical" variant was highest in the minority races and lowest in Africans. Two sisters of Indian descent demonstrated the presence of the silent gene.
Assuntos
Colinesterases/genética , Etnicidade/genética , Variação Genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Colinesterases/sangue , Dibucaína , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Trinidad e TobagoRESUMO
Although the values reported were higher than those reported for Caucasians, differences in dibucaine number for pseudocholinesterase values among the three ethnic groups in Trinidad and Tobago, were not significant. Eight individuals had intermediate dibucaine number values between 40 and 70; one of them was African, 3 were East Indians, and 4 Mixed. Two of the Mixed group were of Portuguese lineage and had significantly lower dibucaine numbers and enzyme concentration. Two sisters of East Indian origin had an inestimable dibucaine number and their pseudocholinesterase values were just detectable, suggesting the presence of a 'silent gene' for pseudocholinesterase. These studies, which are being extended, suggest that the dibucaine number should be estimated prior to succinylcholine administration in patients in Trinidad and Tobago who are at risk of apnoea.