Generalized Edema:  Nephrotic Syndrome

Fluids Case Study

Roger Moor is a 66-year-old long-distance truck driver.  Ten years ago, her was diagnosed with focal segmental glomerulosclerosis (a glomerular disease that causes nephrotic syndrome).  Because he is constantly on the road, Roger found it difficult to have periodic check-ups.  Recently, however, his symptoms were alarming–he had gained weight, his face and legs were swollen, and his pants no longer buttoned around the waist.  Since these are signs that his physician had warned him about, he called in sick and made an appointment for a check-up.  On physical examination, the physician noted periorbital edema, pitting edema of his extremities, and ascites.  Plasma and 24-hour urine values are shown below.

Plasma Concentration 

Na+                                                                                142 mEq/L

Albumin                                                                           1 g/dL (Normal is 4.5 g/dL)

Lipids                                                                               Elevated

24-Hour Urine

Protein                                                                             4 g/24 hr

Lipids                                                                               Positive

1.  As a consequence of long-standing focal segmental glomerulosclerosis, Roger developed nephrotic syndrome, a clinical complex characterized, first and foremost, by proteinuria.  Why was Roger excreting large amounts of protein in his urine?

2.  Why did Roger have hypoalbuminemia, and what is the expected effect on plasma osmotic pressure?

3.  What mechanism can you propose for his hyperlipidemia?  For his lipiduria?

4.  Roger has generalized edema.  What are the 2 definite mechanisms responsible for the generalized edema that is evident in Roger’s case?  Explain how each one causes generalized edema.

5.  In addition to the generalized edema, explain why periorbital edema, pitting edema in the extremities and ascites are occurring?