Automated detection of malaria with haematology analyzer sysmex xe-2100.

Background: Diagnosis of malaria is usually made by microscopy [Giemsa, Acridine Orange (AO), and Quantitative Buffy Coat (QBC) assay], which requires expertise. Currently, automated haematology analyzers are being used for complete blood count (CBC), in all acute febrile and non-febrile illnesses which simultaneously detects malaria. The normal scattergram by the analyzer (Sysmex 2100) comprises of five parameters i.e. lymphocytes (pink), monocytes (green), neutrophils (blue), eosinophils (red) with a space between the neutrophil and eosinophil populations. Aims : We carried out a prospective study to compare the efficacy of Sysmex XE-2100 (Sysmex Corporation, Kobe) for detection of malaria in comparison to other conventional techniques. Materials and Methods : 430 cases were analyzed for malaria by microscopy (QBC, AO, Giemsa), ICT (Immunochromatography) and flowcytometric analyzer (Sysmex XE-2100). The abnormal scattergrams were observed as double neutrophil, double eosinophil, grey zone, extended neutrophil zone with a decrease space between eosinophil and neutrophil, and a combination of above patterns. Results : Out of 70 positive cases [49/70 (70%) P. vivax, 18/70 (25.7%) P. falciparum, and 3/70 (4.2%) both P. vivax and P. falciparum], 52 showed abnormal scattergrams by the analyzer. The sensitivity and specificity of hematology analyzer found to be 74.2% and 88%, respectively. Conclusion : Flowcytometric analyzer is a rapid, high throughput device which needs less expertization for the diagnosis of malaria. Hence, it can be used in the diagnostic laboratories as an early modality for diagnosis of malaria in suspected as well as clinically in apparent cases.

Malaria: the value of the automated depolarization analysis.

This retrospective and descriptive study was carried out in the University of Malaya Medical Center (UMMC) from January to September, 2004. This study aimed to evaluate the diagnostic utility of the Cell-Dyn 4000 hematology analyzer's depolarization analysis and to determine the sensitivity and specificity of this technique in the context of malaria diagnosis. A total of 889 cases presenting with pyrexia of unknown origin or clinically suspected of malaria were examined. Sixteen of these blood samples were found to be positive; 12 for P. vivax, 3 for P. malariae, and 1 for P. falciparum by peripheral blood smear as the standard technique for parasite detection and species identification. Demographic characteristics showed that the majority of patients were in the age range of 20-57 with a mean of 35.9 (+/- SD) 11.4 years, and male foreign workers. Of these, 16 positive blood samples were also processed by Cell-Dyne 4000 analyzer in the normal complete blood count (CBC) operational mode. Malaria parasites produce hemozoin, which depolarizes light and this allows the automated detection of malaria during routine complete blood count analysis with the Abbot Cell-Dyn CD4000 instrument. The white blood cell (WBC) differential plots of all malaria positive samples showed abnormal depolarization events in the NEU-EOS and EOS I plots. This was not seen in the negative samples. In 12 patients with P. vivax infection, a cluster pattern in the Neu-EOS and EOS I plots was observed, and appeared color-coded green or black. In 3 patients with P. malariae infection, few random depolarization events in the NEU-EOS and EOS I plots were seen, and appeared color-coded green, black or blue. While in the patient with P. falciparum infection, the sample was color-coded green with a few random purple depolarizing events in the NEU-EOS and EOS I plots. This study confirms that automated depolarization analysis is a highly sensitive and specific method to diagnose whether or not a patient has malaria. This automated approach may prove to be particularly useful in situations where there is little or no clinical suspicion of malaria.

Automated determination of glucose-6-phosphate dehydrogenase (G6PD) on a SPOTCHECK Microflow analyzer.

Glucose-6-phosphate dehydrogenase (G6PD) is the initial enzyme in the hexose monophosphate pathway of glucose metabolism. Deficiency of G6PD has been linked to increased sensitivity of red cells to hemolytic anemia due to certain oxidant drugs, infectious agents or fava beans. It is an inherited error in metabolism and has a high incidence in certain ethnic groups. Astoria-Pacific has developed an automated assay for use on the SPOTCHECK Microflow Analyzer for the semi-quantitative determination of G6PD activity in erythrocytes. After sample extraction, all assay steps are automated including reagent addition, incubation and data collection. Use of on-line dialysis removes interferences. The assay is intended primarily as a screening tool in the diagnosis and treatment of disease states associated with G6PD deficiency in newborns. G6PD in the dried blood spot is extracted and placed on the instrument. Samples are then aspirated into the system at a rate of 90 samples/hour. All other reagents are added by the SPOTCHECK Analyzer on-line during sample processing. Incubation of each sample occurs on-line at 37 degrees C, and after dialysis the NADPH reaction product is excited at 365 nm. Fluorescence is measured at 500 nm. A lack of fluorescence indicates a probable G6PD deficiency. Data reduction occurs real time through a FASPac software thus individual results are available during a run as soon as each sample analysis is complete. The Astoria-Pacific International G6PD reagent kit paired with the SPOTCHECK Microflow Analyzer provides an effective and easy to use screening tool for determining G6PD deficiency in newborns.

Montaje y estandarización de la determinación de fructosamina sérica en el autoanalizador vitalab-200 / Mounting and standardization of serum fructosamine determinación in the autoanalyser vitalab 200

La cuantificación de fructosamina con fines asistenciales e investigativos se realizó a través de un procedimiento automatizado en un autoanalizador Vitalab-200. basado en el método del nitroblue tetrasolio (NBT) descrito por Johnson. La calibración del método se relizó con el patrón acuoso externo 1-deoxi 1 morfolino fructuosa, y se obtuvo una adecuada respuesta lineal que se corrobora por los resultados del análisis de regresión (r=1.00; p<0.0001). Los coeficientes de variación promedios obtenidos de los estudios de repetibilidad y reproducibilidad fueron 4.3% y 9.1% respectivamente. El estudio para el establecimiento de los rangos de referencia en sujetos normales y en pacientes diabéticos evidenció una distribución normal de valores para ambas poblaciones; el rango de valores de fructosamina obtenido para sujetos normales abarca de 0.5 a 1.3 mmol de fructosamina/L, y para pacientes diabéticos de 1,3 a 3,0 mmol de fuctosamina/L