AssessmentsDyslipidemias: Pathology review
USMLE® Step 1 style questions USMLE
A 26-year-old man is evaluated in the emergency department for epigastric pain that began an hour ago. He reports that the pain radiates to the back and is 9 out of 10 in severity. The patient consumes a diet rich in fresh fruits and vegetables. He drinks 2-3 glasses of wine per week on social occasions. Family history is notable for recurrent episodes of pancreatitis in his father and paternal uncle. His temperature is 37.7°C (99.9°F), blood pressure is 125/83 mmHg, and pulse is 96/min. Physical examination is notable for tenderness on light palpation of the epigastric region. Abdominal exam also reveals hepatosplenomegaly and the following finding:
Reproduced from: Wikimedia Commons
Xanthomas are found on the patient’s bilateral elbows. Which of the following set of laboratory findings would be most likely expected in this patient?
Content Reviewers:Yifan Xiao, MD
Jamie is a 24-year-old male presenting to the emergency department complaining of sudden onset chest pain and shortness of breath when playing soccer.
On further evaluation, his ECG showed ST-segment elevation and laboratory evaluation showed elevated troponin I levels.
After instituting treatment, Jamie and his family inquire about the odd early onset of his disease.
The physical examination of the skin showed numerous xanthomas.
A lipid panel is ordered and shows marked elevation of LDL.
Jamie had a myocardial infarction which was caused by an underlying lipid disorder.
Lipid disorders include both hyper and hypolipidemia.
Hypolipidemia is the opposite where there’s a low level of these lipids.
So let’s do a quick overview of the physiology of lipid metabolism.
These can be taken up by nearby tissues to generate energy, like in the muscle cells, or for storage, like in adipocytes.
But instead of chylomicrons, they are packaged into very low density lipoproteins, or VLDLs.
Compared to chylomicrons, these are made of different lipoproteins and contain a bit more cholesterol.
VLDLs are released from the liver and enter into the blood where lipoprotein lipase in the capillaries break them down again to release triglycerides for nearby tissue to use.
As more and more triglycerides leave the VLDL, it becomes an IDL or intermediate density lipoprotein, and when there’s more cholesterol left than triglyceride, it becomes an LDL.
LDLs then travel around in the blood, where they are endocytosed by cells with LDL receptors.