Diagnostic utility of low hemoglobin density to detect iron deficiency in patients with inflammatory bowel disease

BACKGROUND: In the absence of a feasible noninvasive gold standard, iron deficiency (ID) anemia (IDA) is best measured using multiple indicators. However, the choice of an appropriate single iron biomarker for ID screening continues to be debated. Low hemoglobin density (LHD%) from Coulter counters has been suggested as a useful tool to detect ID. This study investigated the reliability of LHD% for the assessment of iron status in patients with inflammatory bowel disease (IBD) and IDA, anemia of chronic disease (ACD) or mixed anemia (MIX). METHODS: The study population consisted of 143 patients with IBD (aged 39.03±12.53 years, 61.5% female). Blood count, transferrin saturation, serum ferritin, and C-reactive protein were determined by routine assays. Patients with anemia were divided into 3 groups: IDA, ACD and MIX, according to specific criteria. Receiver operator characteristic (ROC) curves were constructed. RESULTS: ROC analysis for LHD% in the detection of ID yielded a cutoff value of 3.8%. In anemic patients, LHD% values did not differ statistically significantly between groups (IDA, ACD, MIX) and no significant difference in LHD% values was observed between patients with IDA and ID. CONCLUSIONS: These results demonstrate that LHD% is a reliable biomarker for the detection of iron deficiency in patients with IBD and anemia, regardless of whether inflammation is present. Our findings indicate that LHD% can provide added value in diagnosing iron deficiency.