Background: In Korea, sarcoidosis is a very rare disease but the first nationwide survey performed in 1992 by the Korean Academy of Tuberculosis and Respiratory Diseases revealed 113 biopsy-proven cases. To investigate whether sarcoidosis is continuously increasing in Korea and verify the clinical pattern, the second nationwide survey was performed.
Method: The questionnaires were sent to hospitals of larger than 80-bed size for collection of biopsy-proven sarcoidosis patients newly diagnosed between July 1992 and June 1999.
Result: A total of 309 biopsy-proven cases was recruited from 58 hospitals. The incidence has gradually increased from 14 cases in 1993 (0.027/100,000) to 59 cases in 1998 (0.125/100,000). The peak age was in the thirties (33%) and females were predominant (64.6%). Not a single case was detected among 190,029 mass chest X-ray films taken in the national tuberculosis surveys from 1980 to 1995. The most common symptom was respiratory (42%) and the most frequently involved organ was the lung (87%), followed by skin (31%). Tuberculin skin anergy was found in 82.2%. Hypercalcemia was found in 9.7% and hypercalciuria in 22.5%. FVC and FEV1 were reduced in about a quarter of the patients and reduced DLCO was found in 37%.
Conclusion: Sarcoidosis is still very rare in Korea even though it is increasing slowly and clinical manifestation was similar to the western pattern.