Abstract
Background: Clinical pallor has traditionally served as a screening tool for anemia; however, its assessment is inherently subjective and lacks objectivity. Therefore, this study aimed to investigate the correlation between skin and mucosal color, as measured by a spectrophotometer, and venous hemoglobin (Hb) values, to identify the optimal anatomical assessment site for detecting anemia.
Methods: A cross-sectional design. Ninety-two adult Japanese outpatients from an urban small hospital in Japan participated in the study. Using a spectrophotometer, the color of the lower lip and palpebral conjunctiva was measured indirectly, while the color of the nails and palms was measured directly. Skin and mucosal color were quantified using the L*a*b* color scale. The color difference (ΔE*) was employed to evaluate the discriminability of anemia identification across different assessment sites. Additionally, venous Hb values were recorded, with anemia defined as Hb <12.0 g/dL.
Results: The a* values of the lip, palpebral conjunctiva, palm, and inside of the upper arm exhibited a positive correlation with Hb values and were significantly lower in the anemic group. While the ΔE* levels for the palpebral conjunctiva and lip were readily discernible by the human eye when comparing the normal and anemic groups, recognition at this level proved challenging for other sites.
Conclusion: The palpebral conjunctiva and lip demonstrate potential suitability for visual diagnosis of anemia. In the nail, palm, and inside of the upper arm, anemia detection may require highly trained observation. Consequently, reliance on these sites for anemia diagnosis may lead to potential oversight.