Lab Notes: Sickle Cell Anemia

One of the most serious hereditary diseases is Sickle Cell Anemia/Sickle Cell Disease. It is an autosomal recessive mutation of a hemoglobin gene which causes "Sickling" of the red blood cells. The decrease in hemoglobin causes outward effects such as fatigue and fainting while internally, the cells can cause blockages in blood vessels, blocking flow.

The gene mutation creates rigid red blood cells, forgoing their typical "donut" shape and becoming a characteristic Sickle Cell  "eyebrow" shape.

It is important to be on the look out for any sickle cells that may be present in a patient's blood smear. Any number is significant and must be reported as either Occasional, Some, Many on the CBC report. It must also be noted that reporting Sickle Cell Anemia is very serious and should be confirmed if you are ever unsure.

The easiest way to look for sickle cells is to look for the distinct "curved eyebrow" shape. It will have sharp-pointed ends with a curved arch in the centre that will stand out from the other RBCs. Some of the cells can appear twisted like they are 'flipping' which is how they appear before they fully sickle.

One of the major issues with diagnosing Sickle Cell Anemia is the confusion with "pencil" RBCs. They are typically seen with IDA (Iron Deficiency Anemia) and can appear to have pointed ends which may be mistaken as Sickle Cell.

Try to familiarize yourself with the difference in appearance between pencil RBCs and Sickle Cells so you can make your diagnosis quickly and correctly.

-K