A 2-year-old child presents with bilateral pitting pedal edema, hepatomegaly, and a 'flaky paint' skin rash. Serum albumin is 1.8 g/dL. The diagnosis is kwashiorkor. Which of the following pathophysiological mechanisms explains the edema in this condition?

• A Increased sodium retention due to elevated aldosterone from malnutrition
• B Lymphatic obstruction due to recurrent infections causing protein-losing enteropathy
• C Increased capillary permeability from cytokine storm secondary to repeated infections
• D Hypoproteinemia reducing oncotic pressure with shift of fluid from vascular to interstitial compartment ✓

Explanation

In kwashiorkor, severe protein deficiency leads to hypoalbuminemia, which reduces plasma oncotic pressure (colloid osmotic pressure). This shifts the Starling equilibrium, allowing net fluid movement from the intravascular compartment into the interstitial space, causing edema. The edema typically starts at the feet and may ascend. Despite edema, the intravascular volume is often reduced, contributing to aldosterone activation as a secondary response.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.