Kerley B lines’ in the chestX-ray of a patient is a radiological feature of-
**Core Concept**
Kerley B lines are short, horizontal lines at the lung periphery, representing interstitial edema. This is a radiological sign of left heart failure, particularly congestive heart failure, where fluid accumulates in the interstitial spaces of the lungs due to increased pressure.
**Why the Correct Answer is Right**
The presence of Kerley B lines is indicative of fluid accumulation in the interstitial spaces of the lungs. This occurs due to the increased hydrostatic pressure in the pulmonary capillaries, which forces fluid out of the capillaries and into the interstitial spaces. The interstitial fluid then gets deposited along the periphery of the lungs, appearing as short, horizontal lines on the chest X-ray. The interstitial edema is often associated with conditions like left heart failure, chronic obstructive pulmonary disease (COPD), and pneumonia.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Kerley B lines are not typically associated with chronic obstructive pulmonary disease (COPD). While COPD can cause interstitial changes, it is more commonly associated with hyperinflation and air trapping.
**Option B:** This option is incorrect because pulmonary embolism does not typically cause Kerley B lines. Pulmonary embolism may cause other radiological signs like Westermark's sign or Hampton's hump.
**Option C:** This option is incorrect because bronchiectasis is a condition characterized by dilated bronchi and bronchioles, which may appear as ring-like structures or tramlines on the chest X-ray, but not typically as Kerley B lines.
**Clinical Pearl / High-Yield Fact**
Remember that Kerley B lines are often seen in the context of left heart failure, and their presence can be a valuable clue in diagnosing this condition. In addition to Kerley B lines, other radiological signs of left heart failure include cardiomegaly, pulmonary edema, and pleural effusion.
**Correct Answer: D. Left heart failure.**