In our renal question today we are asked to identify the pattern we would see on electron microscopy. See if you can find where the question leads you!
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Renal tends to come up in the top 3 of questions where people are going back because they answered them incorrectly or that they're saving and redoing questions in this category. This indicates a level of less confidence or knowledge gap that needs to be filled for most students. Andrea thinks renal is a challenging area being a complicated system with a lot of memorization involved in the different syndromes. It's a combination of genetics and pathophysiology and pathology. You'd have to be able to do everything from figuring out the disorder and knowing what it would look like on biopsy, looking at diagnostic studies and the physiology involved in the different renal disorders.
A 16-year-old boy presents. He recently immigrated from Russiam, has no major medical problems. He does mention he had an episode of light red urine three weeks ago. At the same time, he had a mild cold. He has no known allergies, no recent drug use or medications. His family has traced positive for kidney disease in his maternal uncle, but both of his parents are healthy. He also mentions that he has had lately noticed that he has mild hearing problem but he's never thought much of that. It's asking a kidney biopsy. This patient would most likely show which of the following:
(A) Linear pattern of IGG with fluorescent microscopy
(B) Splitting of the glomerular basement membrane
(C) Mesangial cell proliferation
(D) Epithelial humps or a thickened basement membrane that looks like a train track
The first thing to note here is the hearing loss, which is something that would lead you down a specific road. So we're given a little hint here that can be very helpful. Based on history, the hearing loss would be due to Alport syndrome, which is a collage type 4 mutation resulting in abnormal basement membrane, that includes renal involvement, ocular involvement, and sensory neural hearing loss.
In this question, the answer you'd look at is the splitting of the glomerular basement membrane. The other way to describe this is the basket weave appearance, also known as the glomerular basement membrane lamellation, characterized by the layering and splitting of the membrane.
The key here is the Alport syndrome and remember what the findings would be and that specific disorder.
One possible question could be what other symptoms the patient may be experiencing. How is this commonly inherited because Alport syndrome can be inherited in a X-linked dominant way. You can also look through everything from genetics all the way through the pathology and electron microscopy for each disorder. Or maybe they won't mention hearing loss but vision symptoms or inheritance pattern they've seen in the family, which they did when they mentioned the maternal uncle. So they've hinted this as well.
If the question would have left the hearing loss out, they would probably mention a more extensive family history so you could see the inheritance pattern. They're also mentioning hemoturia so you're led to a nephrotic syndrome. That would also help. But they'd probably give you additional information to lead you down a...