To investigate the diagnostic value of the non-invasive hemoglobin instrument NBM200 in the patients with renal anemia.

A total of 301 patients with kidney diseases were selected in the Department of Nephrology, Chinese PLA General Hospital. The hemoglobin concentration was measured with the non-invasive hemoglobin detector (NBM200) and the blood analyzer (Sysmex), and the two groups of data were used to conduct correlation analysis, construct a regression model, test the consistency, and evaluate the value of the non-invasive hemoglobin detection method in the diagnosis of renal anemia.

There were significant differences between the data of SpHb (non-vasive hemoglobin monitored by spectrophotometry) and THb (true hemoglobin) in the 301 patients with renal diseases (P<0.001). Pearson correlation analysis showed that the data of SpHb was positively correlated with those of THb (r=0.804, P<0.001). 200 cases were randomly selected for establishing a regression model: THb=22.784+ 0.885×SpHb-2.720×stage-3.588×gender, and the remaining 101 cases were used for validating the model, showing an error rate of 7.9%. According to the THb quartile method, the Bland-Altman analysis showed that when the THb was lower than 102 g/L, the consistency of the two detection methods was poor. When the THb was higher than 102 g/L, the two detection methods had good consistency. The specificity of NBM-200 for the diagnosis of renal anemia was 87.9%, and the sensitivity was 75.3%.

In most patients of the department of nephrology, the NBM200 detector was used to obtain a good consistency and correlation between the hemoglobin value and the actual value, showing that it could be used for clinical monitoring of hemoglobin dynamics, but its accuracy needs further improvement. NBM200 detector cannot completely replace the venous hemoglobin test in patients with renal diseases.