Clinical Usefulness of Haptoglobin Levels to Evaluate Hemolysis in Recently Transfused Patients

Abstract

Introduction. Haptoglobin binds the globin portion of free hemoglobin. Serum haptoglobin measurement is used as a laboratory marker for the diagnosis of hemolytic anemia. Since stored blood contains free hemoglobin, transfusion may affect haptoglobin levels. Study Objectives. The aim of the study was to evaluate whether serum haptoglobin could be measured to assess hemolysis in recently transfused patients. Patients and Methods. Twenty-one patients, receiving more than one unit of packed red blood cells (PRBCs) for presumed nonhemolytic indications, were enrolled. Serum haptoglobin levels were recorded before, immediately after, and 24 and 48 hours after transfusion. Observations and Results. Analysis of variance with a repeated measures was used to examine the serum haptoglobin levels at different time periods and no significant difference was found (P = .28). Conclusion. The results suggest that serum haptoglobin can be used in the diagnosis of hemolysis in patients receiving multiple units of PRBC.

Serum proteins and their diagnostic utility in veterinary medicine: a review

“…Decreases in the α 1 -globulin fraction may be detected in α 1 -antitrypsin deficiency, a rare genetic disorder in humans and even more rare in animals (Slev et al 2008). Similarly, the α 2 -globulin zone may typically be decreased in haemolytic anaemia, when haptoglobin from this fraction binds with the free haemoglobin released from the destroyed red blood cells, forming haptoglobin-haemoglobin complexes that are rapidly removed by phagocytes (Vavricka et al 2009;Gupta et al 2011). On the other hand, the inflammatory conditions that develop in association with haemolytic anaemia lead to increased haptoglobin concentrations that may induce an increase in α 2 -globulins (Tecles et al 2005).…”

Inferior Vena Cava Filters as a Potential Non-immune Cause of Low Serum Haptoglobin

“…All patients had a negative antibody screen pre-transfusion and no transfused patient developed new RBC alloantibodies, thereby excluding haptoglobin losses due to a delayed hemolytic transfusion reaction. Furthermore, haptoglobin is not significantly affected by routine RBC transfusion despite recent concerns regarding RBC hemolysis with prolonged RBC storage [28]. Gupta and colleagues performed serial haptoglobin measurements in 21 patients who required RBC transfusion for bleeding (90%) or acute illness [28].…”

“…Furthermore, haptoglobin is not significantly affected by routine RBC transfusion despite recent concerns regarding RBC hemolysis with prolonged RBC storage [28]. Gupta and colleagues performed serial haptoglobin measurements in 21 patients who required RBC transfusion for bleeding (90%) or acute illness [28]. Although there was a transient mild decrease (<10%) in haptoglobin immediately post-transfusion, haptoglobin levels returned to pretransfusion levels within 24 hours.…”

Protection against Heme Toxicity: Hemopexin Rules, OK?

“…Plasma heme levels in normal volunteers are estimated to be ~0.2 µM, 165 and Hp levels range from 2 µM to 23 µM. 166,167 Thus, apo-HPX (at 10-25 µM) often predominates over Hp in biological fluids. Significantly, the amount of Hb present in 5 mL of blood would deplete circulating Hp because the Hp -Hb complexes are degraded after endocytosis.…”