Temporary impairment of reticulocyte haemoglobin content in subjects with community‐acquired pneumonia

Abstract

In the case of inflammation, imbalance of iron homoeostasis is caused by increased retention of iron within cells of the reticuloendothelial system. Iron-restricted erythropoiesis occurs because of decreased availability of iron for haemoglobin (Hb) synthesis in erythroid progenitor cells. Deviations in reticulocyte haemoglobin (Ret-He) content are investigated together with inflammation markers in subjects with community-acquired pneumonia (CAP). Short-term alterations with regard to Ret-He during and after completing antibiotic treatment are investigated. A total of 75 patients, classified into three subgroups with CURB-65 scores of ≤1, 2 and ≥3, participated in the study. Within the three subgroups, Hb results demonstrate a decline from the day of admission until day 4. From day 4, an increase towards higher values is observed at day 14. Within 24 h after admission, Ret-He results are situated within the lower quartile region of the reference range interval. Until day 4 of hospital admission, a steady trend towards a decline of 3-8% is established. During antibiotic treatment, an increase in reticulocyte count occurs from 0.039 ± 0.014 × 10(12) /L at day 4 to 0.057 ± 0.020 × 10(12) /L at day 14 (mean ± SD). Recovery of Hb and Ret-He occurs towards values within the reference range. In subjects with CAP, acute inflammation results in impairment of Ret-He at an early stage. After onset of pneumonia, decreased results of Ret-He and Ret-He/RBC-He ratio are demonstrated, reflecting acute erythropoietic dysfunction, which are amongst others caused by functional iron depletion.