Background: Chronic kidney disease (CKD) is a global health problem. In Mongolia, urine is analyzed by methods of urine chemistry and urine sediment to diagnose kidney disease. The currently automated urine sediment analyzers have been widely used in clinical laboratories and are replacing traditional manual microscopic examination. Nonetheless, visual microscopic examination is still required in many cases. When chemical and sediment analyzers are used together, urine sediment could be confirmed under a microscope, if the results are inconsistent. Sternheimer-Malbin stain has contained a variety of dyes that help to distinguish particles (white blood cells, red blood cells, epithelial cells, casts, crystals, fatty drops, bacteria, yeast, trichomonas) in urine sediment, improve the differentiation between cell nuclei and cytoplasm, and provide more information about cell shape and image.
Therefore, the low-cost method that can be used on a daily basis.Although there are more than 4,500 laboratories in Mongolia that need to perform urinalysis, which is an important part of clinical laboratories, less than 10 percent of hospitals have fully automated sediment analyzers. For this reason, one of the most important issues in the clinical laboratories, the search for low-cost and useful methods for the analysis of urine sediments in order to provide access to services to the public. Our aim was the comparison of methods of the microscopic examination with Shternheimer-Malbin stain and fully automated UF-5000 analyzer for urine sediment. Methods: There was a comparative study, people who served the Clinical Central Laboratory of Mongolia-Japan Hospital received permission to participate in this research. One hundred five fresh, first morning, clean catch mid-stream urine samples were collected in accordance with standard operating instructions for urinalysis, between November 2020 and May 2021. Sternheimer-Malbin (SM) staining and direct microscopy observation methods with Fuchs-Rosenthal counting chamber were used to red blood cells (RBC), white blood cells (WBC) and epithelial cells (EC) in urine samples. The agreements between the automated urine analyzer and microscopic methods were calculated using Cohen’s kappa (k) with 95% confidence intervals (CI). Results: A total of 105 samples were collected and analysed in this study. The average age was 46.97±15.0and gender by 18% (n=19)were male and 82% (n=86) were female.
Compared to traditional manual methods and automated analyzer, the agreement within the same grade was 99/105 (94.3%) for erythrocytes, 96/105 (91.4%) for leukocytes, 92/105 (87.6%) for epithelial cells. And compared to Sternheimer-Malbin staining microscopy observation and automated analyzer, the agreement within the same grade was 98/105 (93.3%) for erythrocytes, 99/105 (94.3%) for leukocytes, 96/105 (91.4%) for epithelial cells. Agreement between traditional manual method and automated analyzer was higher than 85% and between Sternheimer-Malbin staining microscopy observation and automated analyzer was higher than 90%. The concordance between traditional manual method and automated analyzer was substantial (k=0.74, p<0.001; k=0.79, p<0.001) for RBC and EC, almost perfect (k=0.92, p<0.001) for WBC. Whereas the concordance between SternheimerMalbin staining microscopy observation and automated analyzer was substantial (k=0.70, p<0.001) for RBC, almost perfect (k=0.94, p<0.001; k=0.89, p<0.001) for WBC and EC. Comparison of Sysmex UF-5000 with microscopic particle counting methods resulted specificity was 98.9/100% for RBC, sensitivity was 97.7/95.3% and negative predictive value was 98.4/96.8% for WBC, sensitivity was 87.5/68.8% and negative predictive value was 97.8/94.7% for EC. Conclusion The Cohen’s k analysis result of comparisons between the SternheimerMalbin staining microscopic method and automated urine sediment analyzer showed significant almost perfect agreement (k=0.70-0.94, p<0.001).
The sensitivity and negative predictive value were high for both of WBC and EC were determined by Sternheimer-Malbin (SM) staining microscopy observation method. Results indicate the ability of a test to correctly identify those with the true positive and individual with a negative test result is truly negative better than comparison of Sysmex UF-5000 with traditional manual microscopic method assessment.