**Question:** Sabin Feldman dye test is used for diagnosis of which of the following condition:

A. Celiac disease
B. Addison's disease
C. Hypothyroidism
D. Hyperthyroidism

**Correct Answer:**

**Core Concept:**
The Sabin-Feldman dye test is a serological test used to diagnose dermatitis herpetiformis, which is a gluten-induced dermatological condition. It is a type of dermatitis characterized by small, itchy, and painful blisters on the skin. Dermatitis herpetiformis is a manifestation of celiac disease, an autoimmune disorder triggered by the consumption of gluten, a protein found in wheat, barley, and rye. The test's name is derived from the two pioneers who first described the condition, Dr. Ivan Sabin and Dr. Harry Feldman.

**Why the Correct Answer is Right:**
The Sabin-Feldman dye test is rightly identified as a diagnostic tool for celiac disease because dermatitis herpetiformis is a skin manifestation of celiac disease. The test measures the presence of anti-endomysial antibodies (EMA) in the patient's blood, which are associated with celiac disease. When these antibodies are detected, it suggests an underlying celiac disease, as EMA is a hallmark of this condition.

**Why Each Wrong Option is Incorrect:**

**A. Celiac disease:** While dermatitis herpetiformis is a skin manifestation of celiac disease, the Sabin-Feldman dye test is not specifically designed to diagnose celiac disease itself but dermatitis herpetiformis. Therefore, it is incorrect to label the test as a diagnostic tool for celiac disease.

**B. Addison's disease (Primary adrenal insufficiency):** Addison's disease is a separate endocrine disorder affecting the adrenal glands, not related to dermatitis herpetiformis or celiac disease. The Sabin-Feldman dye test is not applicable to diagnose Addison's disease.

**C. Hypothyroidism:** Hypothyroidism is a condition caused by an underactive thyroid gland, whereas dermatitis herpetiformis and celiac disease are associated with an overactive immune response. The Sabin-Feldman dye test is not relevant to diagnose hypothyroidism.

**D. Hyperthyroidism (Hyperthyroidism):** Hyperthyroidism is caused by an overactive thyroid gland, while dermatitis herpetiformis and celiac disease are associated with an underactive thyroid. The Sabin-Feldman dye test is not applicable to diagnose hyperthyroidism.

**Core Concept:**

The Sabin-Feldman dye test is primarily used to diagnose celiac disease and dermatitis herpetiformis due to its association with an overactive immune response against gluten in genetically predisposed individuals. The test measures the level of anti-endomysial antibodies (EMA), which are present in dermat