Increased mean corpuscular haemoglobin concentration: artefact or pathological condition?

Area of Science:

• Hematology
• Clinical Laboratory Science
• Flow Cytometry

Background:

• Spurious elevations in Mean Corpuscular Hemoglobin Concentration (MCHC) trigger analytical alarms in hematology labs.
• Accurate MCHC values are crucial for timely and correct clinical decisions.

Purpose of the Study:

• To develop a decision tree for managing elevated MCHC.
• To utilize novel Sysmex XN-10 RET parameters (RBC-O, HGB-O) for accurate result interpretation.

Main Methods:

• Analysis of 128 patients with MCHC > 365 g/L.
• Parallel measurement of erythrocyte and reticulocyte parameters, blood smears, chemistry, and osmolarity.
• Comparison of optical (RBC-O, HGB-O) versus impedance/photometry (RBC, HGB) parameters.

Main Results:

• Four patient groups identified: RBC agglutination (n=22), optical interference (n=17), RBC disease (n=18), and others (n=71).
• RBC-O and HGB-O corrected abnormalities in 36/39 patients with agglutination/interference.
• Reticulocyte parameters enabled an RBC score for sensitive RBC disease detection (17/18 patients).

Conclusions:

• A decision tree based on RBC-O and HGB-O parameters is proposed.
• This approach saves time and aids biological interpretation of elevated MCHC.
• The decision tree improves diagnostic efficiency in hematology.