Seen in vernal catarrh are:
**Core Concept**
Vernal catarrh, also known as vernal keratoconjunctivitis (VKC), is a seasonal, allergic eye condition characterized by chronic inflammation of the conjunctiva and cornea. It is often associated with a strong allergic response to environmental allergens, such as pollen, dust, and mold.
**Why the Correct Answer is Right**
The correct answer is eosinophilia. Eosinophilia is a hallmark feature of vernal catarrh, where an increased number of eosinophils are present in the conjunctival scrapings. Eosinophils are a type of white blood cell that plays a key role in the body's allergic response. In VKC, eosinophils are activated and accumulate in the conjunctiva, contributing to the inflammation and tissue damage characteristic of the condition. This is due to the release of cytokines and other chemical mediators by eosinophils, which exacerbate the allergic response.
**Why Each Wrong Option is Incorrect**
**Option A:** is incorrect because giant cells are more commonly associated with granulomatous conditions, such as sarcoidosis or tuberculosis.
**Option B:** is incorrect because plasma cells are typically found in conditions with a strong humoral immune response, such as rheumatoid arthritis or Sjögren's syndrome.
**Option C:** is incorrect because lymphocytes are a type of white blood cell involved in cell-mediated immunity, but they are not the primary cell type associated with vernal catarrh.
**Clinical Pearl / High-Yield Fact**
Remember that vernal catarrh is a chronic, seasonal condition that often affects young adults, particularly males. It can be challenging to diagnose and manage, but treatment typically involves a combination of topical corticosteroids, immunomodulatory agents, and environmental controls to reduce exposure to allergens.
**Correct Answer: D. Eosinophilia.**