Correlation and interconversion between erythrocyte cholinesterase values obtained by the Michel and the EQM® techniques

Jaime Carmona-Fonseca, .

Keywords: acetylcholine, acetylcholinesterase, pesticides, cholinesterase inhibitors, epidemiological surveillance

Abstract

Introduction. Several techniques are available to measure red cell cholinesterase; therefore, evaluations with several methods provide a measure of concordance.
Objective. An equation was formulated to transform native data of reference values to reference units of cholinesterase activity as measured by Michel and EQM® tests.
Materials and methods. The experimental design was descriptive, transversal and prospective. The group sampled was a representative adult working population, aged 18-75, without previous exposure to cholinesterase inhibitors pesticides. The individuals were affiliated to the Social Security System and resided in Valle de Aburrá and Cercano Oriente Antioqueño (Antioquia Province, northwestern Colombia).
Results. Of 827 individuals, quantitative erythrocytes (Michel y EQM®) tests exhibited "r" coefficients between 0.67 and R2 coefficient of 44%. This indicated that one test explained the results in other test in 44% of the cases. The corelation was higher in Aburrá than in Oriente. The linear model for the 827 individuals was as follows: EQM U/g oxy-hemoglobin = 9.575 U/g oxy-hemoglobin + 29.791 (Michel delta pH/hour). Michel delta pH/hr = 0.3312 delta pH/hour + 0.0149 (EQM U/g oxy-hemoglobin), where EQM® was expressed in U/g oxy-hemoglobin and Michel pH change/hr. Inter-sections (coefficient a) and inclines (coefficient b) were significant in this model. In the adjusted equations, after exclusion of 12 extreme data (1.5% of 827), the r coefficient increased from 0.67 to 0.72 The adjusted equations were as follows: EQM U/g oxy-hemoglobin = 8.1884 U/g oxy-hemoglobin + 31.3920 (Michel delta pH/hour); Michel delta pH/hr = 0.2925 delta pH/hr + 0.0161 (EQM U/g oxy-hemoglobin).
Conclusion. This system of linear equations permitted the transformation of Michel (delta PH/ hr) units to EQM (U/g oxy-hemoglobin) units and vice versa. This will facilitate data comparisons by clinicians and epidemiologists who are using these methods of cholinesterase measurement.

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  • Jaime Carmona-Fonseca Grupo de Malaria, Facultad de Medicina, Universidad de Antioquia, Medellín, Colombia.

References

1. Henao S, Corey G. Plaguicidas inhibidores de las colinesterasas. Serie Vigilancia 11. Centro Panamericano de Ecología Humana y Salud. Metepec: ECO, OPS, OMS; 1991.
2. International Programme on Chemical Safety (IPCS). Organophosphorous insecticides: a general introduction. Environmental Health Criteria Nº 63. Geneve: WHO, ILO; 1986.
3. International Programme on Chemical Safety (IPCS). Carbamate pesticides: a general introduction. Environmental Health Criteria Nº 64. Geneve: IPCS;1986.
4. Whittaker M. Cholinesterase. Monographs in Human Genetics, Nº 11. New York: Karger Basel; 1986.
5. Guyton AK. Tratado de fisiología médica. 10 ed. México, D.F.: Interamericana-Mc Graw Hill; 2000. 6. Schwarz M, Glick D, Lowenstein Y, Soreq H. Engineering of human cholinesterases explains and predicts diverse consequences of administration of various drugs and poisons. Pharmacol Ther 1995;67:283-322.
7. Carlock LL, Chen WL, Gordon EB, Killeen JC, Manley A, Meyer LS, et al. Regulating and assessing risks of cholinesterase-inhibiting pesticides: divergent approaches and interpretations. J Toxicol Environ Health B Crit Rev 1999;2:105-60.
8. Aldridge WN. The nature of the reaction of organophosphorus compounds and carbamates with esterases. Bull World Health Organ 1971;44:25-30.
9. Kangas J, Jauhiainen A. Determination of cholinesterase activity. Afr Newslett Occup Health Safety 1991;2:56-8.
10. Michel HO. An electrometric method for determination of red blood cell and plasma cholinesterase activity. J Lab Clin Med 1949;34:1564-8.
11. Nabb DP, Whitfield F. Determination of cholinesterase by the automated delta pH stat method. Arch Environ Health 1967;15:147-54.
12. Rider JA, Hodges JL Jr, Swader J, Wiggins AD. Plasma and cell cholinesterase in 800 "healthy" blood donors. J Lab Clin Med 1957;50:376-83.
13. Ellman GL, Courtney KD, Andres V, Featherstone RM. A new rapid colorimetric determination of acetylcholinesterase activity. Biochem Pharmacol 1961;7:88-95.
14. Magnotti RA Jr, Eberly JP, Quarm DE, McConell RS. Measurement of acetylcholinesterase in erythrocytes in the field. Clin Chem 1987;33:1731-5.
15. Magnotti RA Jr, Dowling K, Eberly JP, McConell RS. Field measurement of plasma and erythrocytes cholinesterases. Clin Chem Acta. 1988;176:315-32.
16. Riddles PW, Blakeley RL, Zerner B. Reassessment of Ellman's reagent. Methods Enzymol 1983;91:49-60.
17. EQM Research Inc. Cholinesterase kit for the field determination of pesticide exposure. Instruction manual. Cincinnati: EQM; 1994.
18. Tintometer. Lovibond. The Lovibond cholinesterase test kit AF 267 (40-2670). Instruction manual. Virginia,USA: Tintometer; sin fecha.
19. Morales L, Silva E, Ortiz JE, Ramírez P, García A. Intoxicación por plaguicidas en el departamento del Valle del Cauca, 1997. Inf Quinc Epidem Nac 1998;3:222-5.
20. Idrobo AJ. Intoxicaciones masivas con plaguicidas en Colombia. Biomédica 1999;19:67-76.
21. Henao GL, Bolívar JA, Orozco RE. Análisis de las intoxicaciones en el departamento de Antioquia. Inf Quinc Epidem Nac 2003;8:305-20.
22. Varona M, Morales L, Ortiz J, Sánchez J, Cárdenas O, De la Hoz F. Panorama epidemiológico de exposición a plaguicidas inhibidores de colinesterasa en 17 departamentos del país. Biomédica 1998; 18:22-9.
23. Silva E, Morales L, Ortiz JE. Evaluación epidemiológica de plaguicidas inhibidores de acetilcolinestersas en Colombia, 1996-1997. Biomédica 2000;20:200-9.
24. Silva E, Morales L, Ortiz JE, Díaz ML. Evaluación epidemiológica de plaguicidas en el departamento del Meta. Programa VEO, 1996 a 19997. Inf Quinc Epidem Nac 2002;7:389-401.
25. Henao S, Zapata FM, Restrepo MP, Marín LE, Ramírez H, Corrales R, et al. Actividad colinesterásica en menores trabajadores. Antioquia (Colombia), 1989-1990. Medellín: Seguro Social, Universidad de Antioquia; 1990. p.115.
26. Carmona-Fonseca J, Henao S, Garcés R. Valores de referencia de actividad colinesterásica sanguínea en población laboral activa no expuesta a plaguicidas inhibidores de colinesterasa. Rev Fac Nal Salud Publ (Medellín) 2000;18:55-72.
27. Carmona-Fonseca J. Valores de referencia de la actividad de la colinesterasa eritrocitaria según las técnicas de Michel y EQM® en población laboral de Antioquia, Colombia. Rev Panam Salud Pública
2003;14:316-24.
28 Carmona-Fonseca J. Valores de referencia de colinesterasa plasmática con los métodos de Michel, EQM® y Monotest® en población laboral activa del departamento de Antioquia, Colombia. Biomédica
2003;23:437-55.
29. Carmona-Fonseca J. Valores de colinesterasas en trabajadores activas embarazadas, menstruantes, usuarias de anticonceptivos o menopáusicas. Rev Col Obstet Ginecol 2003;54:146-56.
30. Carmona-Fonseca J. Valores de referencia de hemoglobina y hematocrito en una población laboral colombiana. Acta Med Colom 2003;28:63-70.
31. Carmona-Fonseca J. Colinesterasas eritrocitaria y plasmática en trabajadores con enfermedades crónicas controladas y en usuarios de medicamentos. Iatreia 2006;19:14-28
32. Da Silva ES, Midio AF. Interconversion of units of three methods for blood cholinesterases. Med Lav 1998;89:265-72.
33. Newman MA, Que Hee SS. Interconversion and comparison of the results of three methods for cholinesterase in serum. Clin Chem 1984;30:308-10.
34. Groff WA, Kaminskis A, Ellin RI. Interconversion of cholinesterase enzyme activity units by the manual delta pH method and a recommended automated method. Clin Toxicol 1976;9:353-8.
35. Morse CS. Interconversion of cholinesterase measurements by the deltapH method of Michel and the DTNB method of Garry and Routh. Clin Toxicol 1974;7:389-93.
36. Grainger MM, Groff WA, Ellin RI, Arsenal E. Blood cholinesterase values. Correlation obtained by automated and manual techniques. Arch Environ Health 1968;16:821-2.
37. Altamar-Rios J. Herbicidas y malformaciones congénitas en Meta (Colombia). An Otorrinolaringol Ibero Am 2002;29:1-20.
38. Sánchez JF, Morales L, Varona M, Camacho M, Ortiz J, De La Hoz F. Exposición a plaguicidas inhibidores de colinesterasa en 17 departamentos. Inf Quinc Epidem Nac 1997;2:10-12.
How to Cite
1.
Carmona-Fonseca J. Correlation and interconversion between erythrocyte cholinesterase values obtained by the Michel and the EQM® techniques. biomedica [Internet]. 2006 Dec. 1 [cited 2024 May 16];26(4):546-55. Available from: https://revistabiomedica.org/index.php/biomedica/article/view/324

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Published
2006-12-01
Section
Original articles

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