Question

What may cause local gigantism with varicosities?

• A. Arteriovenous (AV) fistulae
• B. Deep vein thrombosis
• C. Acromegaly
• D. Osteosarcoma

Hint:

Think of what abnormal vessel connection sends extra arterial flow into just one limb.

Answer 1

The Correct Option is A

Step 1: Understand local gigantism.
Local gigantism means one limb or body part grows larger than normal because of extra blood flow or extra growth signal reaching that part alone, unlike acromegaly which affects the whole body.

Step 2: Recall how an arteriovenous (AV) fistula causes this.
An AV fistula is an abnormal direct connection between an artery and a vein, bypassing the capillary bed. This sends high pressure, high flow arterial blood straight into the venous system of that limb.
The extra blood flow feeds the growing bones and soft tissue of the limb, so the limb grows larger than the other side, a state called local gigantism.
The same high flow also distends and dilates the superficial veins draining the limb, producing varicosities, so both features, limb overgrowth and varicose veins, are explained by one underlying AV fistula.

Step 3: Rule out the other options.

(B) Deep vein thrombosis: This blocks outflow and causes a swollen, painful leg, but it does not cause true bony or soft tissue overgrowth.

(C) Acromegaly: This is caused by excess growth hormone and enlarges the whole body symmetrically, including hands, feet, and jaw, not one limb alone.

(D) Osteosarcoma: This is a bone tumor that causes a local mass and pain, not diffuse limb overgrowth with varicose veins.

Step 4: Final answer.
The cause of local gigantism with varicosities among these options is an arteriovenous fistula.
\[ \boxed{\text{Arteriovenous (AV) fistula}} \]