Block 2 Case 7 Answers - Vascular

An obese patient presents to the office with complaints of persistent headaches. His kidney function has rapidly deteriorated. The opthalmologist noted retinal exudates, edema and hemorrhages. You have been treating his hypertension and had been relatively well controlled until recently. His blood pressure is 210/130.

What is likely the cause of his HTN?

  >90% of HTN is idiopathic. It is likely that that is the cause of his baseline hypertention. However, the acute changes in his blood pressure suggest a secondary cause - such as renal artery stenosis, diabetic nephropathy, renal cell carcinoma, cushings, pheochromocytoma, ect.

Several years ago before his HTN progressed this far biopsies were taken to examine his vasculature. They are shown below: What do you see?

This is an example of hyaline Arteriolosclerosis. Note the glassy-esoinophilic acellular thickened media. The enlarged media imposes on the lumen leading to a narrow lumen. Hyaline arteriolosclerosis occus due to chronic hemodynamic stress, increased smooth muscle synthesis of matric and plasma protein insudation. These can be associated with benign HTN, diabetes, or aging.



Current biopsy of the kidney shows the following: Describe the pathology:

low power view of the kidney

The top is a low power view of the patient's malignant nephrosclerosis -with fibrinoid necrosis and hyperplastic arteriolitis. Note the changes due to the progression to malignant HTN.

Note the thickened wall and "onion-skin" appearance of the media resulting int a tiny lumen in the high power view on the top (hyperplastic arteriolitis).  

Malignant HTN is also associated with fibrinoid necrosis.

Why might his heart be enlarged? 
Due to the patient's poorly controlled hypertension his heart has had to generate more pressure to pump the blood through his body. In order to do so the heart has undergone concentric hypertrophy. If you were to take a slice through his heart you would see a reduced lumen size and a L. ventricular wall >2cm thick.

What is the characteristic pathological finding?

Boxcar nuclei - this is due to hypertrophied muscle fibers.