Observe the following images, one at around 20x and the other digitally zoomed in, and answer the question:
Now, zoomed in:
Which of the following best describes this patient?
A. Is middle aged, has diabetes
B. Is elderly, has no pathological change
C. Under 20, has cancer
D. Is under 1, has no pathological change
What organ/tissue or pathology is this? (No multiple choice here)
Do you have your answer? Please read the following brief explanation:
One thing I have always loved about pathology is the ability to look under the microscope and see how we are composed from the perspective of microanatomy. I can’t imagine how exciting this was for the first pathologists that did this in the late 1800s. The answer to this particular case is D. Is under 1, has no pathological change. In fact, this is from a fetus, and it is a KIDNEY.
The fetal kidney is a beautiful structure to look at; in the blown up image you can appreciate those rounded structures which are glomeruli. Most of the rest of the field are renal tubules and small blood vessels. To go over the other options on our quiz question, adult kidneys tend to have a more “eosinophilic” (pink) stain to the tissues, especially the glomeruli and tubular cells. Also, if diabetes were present, the lesion we are looking for is an aberration of the glomeruli called a Kimmelstiel-Wilson lesion. (Getting a little advanced here but I will show one soon).
One can rule out elderly based on a couple of things: A microscopic field of an elderly individual does not have this many glomeruli. As we age we start to lose glomeruli either to underlying conditions or just the general degeneration of getting older. As I said before, adult kidneys tend to be eosinophilic whereas fetal or infant kidneys tend to be more basophilic/amphophilic (purple looking), mainly because the nuclei are a bit more well defined.
There is no hint of cancer in this specimen. I wouldn’t expect most of you to know that, but one thing about cancer is that it distorts the architecture of the organ; even without training you can see that the microanatomy of the kidney we are looking at has regular, repeating architecture.
As a forensic pathologist who also works at hospitals, I often have to perform autopsy on pregnancy loss/fetuses. Most often we look at the organs and they appear normal but in perhaps 1/4 to 1/3 of cases I will find a pathological change (such as infection or congenital anomaly) that can explain the death. This is helpful for the doctors and the parents. Even when we don’t find a cause at autopsy, the doctor may correlate clinically and identify maternal factors that caused death.
—DLW
I’m a LONG way from knowing microscopic pathology, but hopefully these slides as explanations will help me learn to identify more along the way.
Are all the little purple spots, throughout, considered basophils?
There is a disease whereby the nucleus is pushed toward the outer edge of each cell. It has been a while since studying it, but I'm fascinated.
I would like to know what all those purple spots are.