What's under the microscope.

As most of you will be aware, red blood cells are not spheres, but bi-concave discs. One of the interesting things about their shape, is how they align themselves in a formation called Rouleaux.

I was performing an in-saline agglutination test on a patient (a dog), checking for evidence of disseminated, intra-vascular coagulation (a condition where the body attacks it's own red blood cells), when the Rouleaux formation appeared.

The Rouleaux formation is normal but seldom so spectacular and I thought it would be nice to share an image, as the one on Wikipedia is pretty pathetic at illustrating the phenomenon.