Sarcoidosis in Korea: report of the Second Nationwide Survey

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.

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.

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%.

Sarcoidosis is still very rare in Korea even though it is increasing slowly and clinical manifestation was similar to the western pattern.