How long after the Kveim test injection are results assessed?

• A. 1-2 weeks
• B. 2-3 weeks
• C. 4-6 weeks
• D. 6-8 weeks

Answer: (C)

The Kveim test is utilized primarily for the diagnosis of sarcoidosis and involves injecting a specific antigen derived from the spleen of a patient with sarcoidosis into the skin of another individual. The results are assessed to determine if a granulomatous reaction occurs at the injection site, indicating a positive response.

Typically, the evaluation of the injection site for a reaction occurs around 4 to 6 weeks post-injection. This timeframe allows sufficient time for the immune response to develop and for any associated skin changes to become apparent. A reaction within this period suggests that the patient may have sarcoidosis, whereas a lack of reaction can indicate that the disease is unlikely.

Choosing a timeframe of 1-2 weeks or 2-3 weeks would not allow for adequate observation of the immune response, which generally develops more slowly. Additionally, waiting much longer than 6 weeks would also be impractical, as the response would likely plateau or resolve before assessment. Thus, the 4 to 6 weeks option reflects the standard practice and understanding of the immunological response to the Kveim test.