CLT Pathophysiology of Lymphedema

Question 1

Which stage of lymphedema according to the International Society of Lymphology (ISL) is characterized by pitting edema that resolves completely with limb elevation?

Accepted Answer

Stage I

Answer

Stage 0 (Latency)

Answer

Stage II

Answer

Stage III

Question 2

What is the primary pathophysiological mechanism that distinguishes lymphedema from other forms of edema?

Accepted Answer

Accumulation of protein-rich fluid due to impaired lymphatic transport

Answer

Increased capillary hydrostatic pressure

Answer

Decreased plasma oncotic pressure from hypoalbuminemia

Answer

Increased capillary permeability from inflammation

Question 3

Which of the following is the most common cause of secondary lymphedema worldwide?

Accepted Answer

Filariasis (parasitic infection)

Answer

Breast cancer treatment

Answer

Trauma and surgery

Answer

Chronic venous insufficiency

Question 4

In the Starling equilibrium, which forces favor fluid movement OUT of the capillary into the interstitium?

Accepted Answer

Capillary hydrostatic pressure and interstitial oncotic pressure

Answer

Plasma oncotic pressure and interstitial hydrostatic pressure

Answer

Plasma oncotic pressure and capillary hydrostatic pressure

Answer

Interstitial hydrostatic pressure and interstitial oncotic pressure

Question 5

What is the primary protein responsible for generating oncotic pressure within the plasma, and what happens to interstitial protein concentration in chronic lymphedema?

Accepted Answer

Albumin; increases due to impaired lymphatic clearance

Answer

Fibrinogen; decreases over time

Answer

Globulin; remains stable throughout disease progression

Answer

Fibronectin; decreases as fibrosis develops

Question 6

Which pathological change is characteristic of ISL Stage III lymphedema (lymphostatic elephantiasis)?

Accepted Answer

Tissue fibrosis, acanthosis, and skin changes with non-pitting edema

Answer

Reversible pitting edema with elevation

Answer

Subclinical impairment with normal limb volume

Answer

Moderate pitting edema that does not resolve with elevation

Question 7

The 'safety valve' function of the lymphatic system refers to its capacity to do which of the following?

Accepted Answer

Increase transport capacity up to 10 times normal to handle excess interstitial fluid

Answer

Prevent blood pressure from rising during exercise

Answer

Regulate sodium balance in the interstitial compartment

Answer

Filter bacteria before they enter the bloodstream