Conjunctival vasculature in the assessment of anemia

Objective: To assess the correlation of the bulbar conjunctival blood colum n (BCBC) with anemia. Design: A prospective, randomized, masked, two observer case series. Participants: Inpatients on hospital wards; outpatients in both the Hematol ogy-Oncology and Ophthalmology Clinics, Methods: Observations of the palpebral conjunctival hue (PCH) and BCBC by t wo observers masked to the patient's diagnosis, laboratory test results, an d other's observations. The PCH and BCBC were correlated by slit-lamp exami nation with serum hemoglobin values. Different threshold levels for anemia were defined as hemoglobin <10, <11,and <12 mg/dl, Main Outcome Measures: The parameters included determination of (1) the con junctival hue, assessed as pink or pale and (2) the bulbar conjunctival blo od column, assessed as full (normal), granular, or discontinuous. These dat a were compared against the patient's hemoglobin level. Results: Mean hemoglobin was 11.0 +/- 2.2 mg/dl, Sensitivity of the BCBC an d PGH for anemia was 83%-94% and 38%, respectively, regardless of the defin ition of anemia. Specificity of BCBC improved with increasing hemoglobin th reshold levels for anemia: 56% (hemoglobin <10 mg/dl) to 73% (hemoglobin <1 2 mg/dl); specificity for PCH ranged from 82% to 94%, The BCBC was signific antly (P < 0.03) associated with anemia for hemoglobin <11 mg/dl for both o bservers (logistic regression, Spearman correlation). There was a significa nt (P < 0,05) association of PCH with anemia only for hemoglobin <10 mg/dl with logistic regression (one observer only) and with Spearman correlation (both observers), Conclusions: The BCBC is significantly associated with anemia, with higher sensitivity and only slightly less specificity than PCH. (C) 2000 by the Am erican Academy of Ophthalmology.