USMLE Step 1 Questions: Physiology

USMLE STEP 1 Practice Question

Today we start a new feature on the blog with a focus on USMLE Step 1 Practice Questions. Here we have a two part physiology question: An obese, pregnant, 26-year-old woman was seen in the emergency room complaining of dizziness and lack of urination. Physical examination suggests that she is 38 weeks LMP. She was markedly edematous. Soon after admission to the hospital, she experienced severe convulsions. Her baby was delivered by emergency cesarean section and the woman recovered her health soon after delivery. 1. The clinical findings are most compatible with the diagnosis of

(a) Choriocarcinoma

(b) Hydatidiform mole

(d) Eclampsia

(e) Oligohydramnios 2. An effective drug of choice in treatment of this disease would have which physiologic effect?

(a) Reduce uterine irritability

(b) Prevent cervical dilation

(d) Relax arterial smooth muscle

(e) Arrest mitosis —–

USMLE STEP 1 Practice Question Answer

The answers are: 1-D; 2-D. This woman presents classical signs of eclampsia. Typically, eclampsia occurs near term. Arterial spasms lead to malignant hypertension and decrease in renal perfusion. The glomerular basement membranes are thickened by protein deposits. Salt and water retention and edema are results of decreased renal function. Loss of protein in the urine is also common in eclampsia. In the extreme cases, eclampsia is characterized by vascular spasms, convulsions and coma, renal failure, hepatic malfunction, and, if untreated, death. Rapid administration of vasodilators will lower blood pressure and delivery of the fetus by cesarean section usually produces rapid recovery.