Tareq Abadl: Polychromasia as a Morphologic Indicator of Bone Marrow Response
Tareq Abadl, Medical Laboratory Specialist and Director of the Blood Bank at Dr. Abdelkader Al-Mutawakkil Hospital, shared a post on LinkedIn:
“Polychromasia — When the Bone Marrow Says: ‘I’m Trying’
Sometimes, those bluish red cells on a peripheral smear are more than just a color change… they’re a message from the marrow.
What is Polychromasia?
Polychromasia refers to red blood cells (RBCs) that appear larger and bluish-gray on a peripheral blood smear.
This happens because these cells still contain residual RNA, making them less mature than normal RBCs.
In simple terms:
Polychromasia is a visible sign of immature RBCs in circulation.
And it often correlates with reticulocytosis.
Why Does It Matter?
Because it tells you something critical: The bone marrow is actively responding.
When you see polychromasia, ask yourself:
Is the body trying to compensate for anemia?
Clinical Significance
Polychromasia is commonly seen in conditions where RBC destruction or loss is increased, such as:
- Hemolytic anemia
- Acute or chronic blood loss
- Warm autoimmune hemolytic anemia (WAHA)
According to the American Society of Hematology (ASH) Image Bank, polychromasia is a hallmark feature in WAHA, reflecting increased marrow activity to replace destroyed red cells.
Why the Peripheral Smear Still Matters?
Even in advanced lab settings, the smear remains powerful:
A simple color change in RBCs can shift your thinking from:
‘Just low hemoglobin’ to ‘Is there hemolysis? Blood loss? Marrow response?’
Don’t Forget the Reticulocyte Count!
Always correlate smear findings with: Reticulocyte count
Because together they answer: Is the marrow responding appropriately or not?
Bottom Line
Polychromasia is not just a morphology finding…
It’s a functional clue that the marrow is working hard to restore balance.”

Other posts featuring Tareq Abadl on Hemostasis Today.
-
May 24, 2026, 13:10Thomas Pincez: Emerging Challenges in Sickle Cell Disease Gene Therapy and Cancer Risk
-
May 24, 2026, 12:04Kalpana Gupta Shekhawat: Ferritin Is More Than an Iron Marker
-
May 24, 2026, 11:50Peter Zdziarski: Making Rare Disease Research More Human
-
May 24, 2026, 11:39Bram Berkelmans: Donating with a View
-
May 24, 2026, 11:28Ratiporn Chinthammit: A Meaningful Exchange in aHUS and PNH Education
-
May 24, 2026, 11:17Mary Ann Sromoski: Transfusion Medicine and Patient Blood Management in Practice
-
May 24, 2026, 07:45Thierry Burnouf: Advances in Platelet Membrane-Coated Nanoparticles for Targeted Therapeutics and Regenerative Medicine
-
May 24, 2026, 07:39Shamala Thilarajah: Our Team Receives the NMRC Transition Award for NEUROACT-Stroke
-
May 24, 2026, 05:48Yazan Abou-Ismail: Contributing to the Future of von Willebrand Disease Management