Valor diagnóstico de la electroforesis de proteínas y cadenas ligeras libres en suero en el mieloma múltiple / Diagnostic value of serum protein electrophoresis and free light chains in the multiple myeloma's diagnosis

RESUMEN Fundamento: La electroforesis de proteínas y las cadenas ligeras libres en suero son técnicas utilizadas en el diagnóstico del mieloma múltiple. Sin embargo, la utilidad diagnóstica de ambas pruebas puede variar según el método empleado y condiciones reales del medio donde se realicen. Objetivo: Determinar el valor diagnóstico de la electroforesis de proteínas y de las cadenas ligeras libres en suero en el mieloma múltiple. Metodología: Se realizó un estudio retrospectivo de los parámetros electroforesis de proteínas en suero y cadenas ligeras libres en suero a 43 pacientes con diagnóstico de mieloma múltiple por evaluación de la médula ósea. La electroforesis de proteínas se realizó por el método convencional de separación de proteínas sobre papel de acetato de celulosa y para las cadenas ligeras libres se aplicó un ensayo inmunoturbidimétrico en el que se usó un analizador químico (Cobas 311). Se calcularon 7 parámetros que evaluaron la exactitud diagnóstica. Resultados: Todos los parámetros que evaluaron la exactitud diagnóstica estuvieron dentro de los intervalos de confianza en ambas pruebas. Conclusiones: La electroforesis de proteínas y las cadenas ligeras libres en suero son ensayos de gran utilidad en el diagnóstico del mieloma múltiple y se deben utilizar en conjunto para la mayor captación posible de casos.

ABSTRACT Background: Protein electrophoresis and serum free light chains are techniques used in the diagnosis of multiple myeloma. However, the diagnostic utility of both tests may vary according to the method used and the actual conditions of the environment where they are performed. Objective: To determine the diagnostic value of protein electrophoresis and serum free light chains in multiple myeloma. Methodology: A retrospective study of serum protein electrophoresis parameters and serum free light chains was conducted in 43 patients diagnosed with multiple myeloma by bone marrow evaluation. Protein electrophoresis was completed by the conventional method of protein separation on cellulose acetate paper and for free light chains an immunoturbidimetric assay was applied in which a chemical analyzer (Cobas 311) was used. Seven parameters were calculated to evaluate diagnostic accuracy. Results: All parameters assessing diagnostic accuracy were within confidence intervals in both tests. Conclusions: Protein electrophoresis and serum free light chains are very useful assays in the diagnosis of multiple myeloma and should be used in conjunction for the highest possible approval of cases.

Hemoglobin F level in different hemoglobin variants

BACKGROUND: Fetal hemoglobin (HbF) levels in different hemoglobin variants in Osogbo, Nigeria, were estimated using two principal methods of estimation using existing information for HbF concentration and distribution of various hemoglobin variants in the area, as well as diagnosed cases of thalassemia. Two hundred and sixty samples collected from HbSS, HbSC, HbAA, HbAS, and HbAC subjects were analyzed. HbF level and hemoglobin type were determined in this study. METHODS: The hemoglobin type was determined using cellulose acetate electrophoresis at an alka-line pH, and HbF was determined by the acid elution and alkaline denaturation methods. RESULTS: The mean+/-SD of HbF in the respective hemoglobin variants was as follows: HbSS, 2.09+/-1.94%; HbSC, 0.85+/-0.54%; HbAA, 0.69+/-0.46%; HbAS, 0.52+/-0.31%; and HbAC, 0.57+/-0.26%. The mean HbF level across the hemoglobin variants was statistically significant (P<0.05). Investigating the sex distribution of the HbF level in the studied population revealed a slightly higher mean HbF level in females than in their male counterparts. CONCLUSION: Within the study population, the HbF level was found to be highest in HbSS and lowest in HbAS. The two methods of estimating HbF are equally reliable, since there was no significant difference between the results obtained from the two methods.

Association of erythrocyte acid phosphatase phenotypes with myopia.

Acid phosphatase is a polymorphic nonspecific orthophosphate monoesterase which catalyses the cleaving of phosphoric acid and subsequent breakdown of several monophosphoric esters under acidic pH conditions. Acid phosphatase has a physiologic function as a flavin mononucleotide phosphatase (FMN) and regulates the intracellular concentrations of flavin coenzymes that are electron carriers in the oxidative phosphorylation pathway. Myopia or nearsightedness is caused by both environmental and genetic factors. Myopic eyes when subjected to excessive oxidative stress results in retinal detachments .In the present study there is a significant elevation of AA phenotype in myopes when compared to controls. The AA phenotype is more susceptible to oxidative stress and its lower enzyme activity is known to be associated with increased intrauterine growth that further results in increased axial length in progressive myopia. The AA phenotype also confers risk for myopia development in males, early age group and cases with parental consanguinity.