Correlation of matrix metalloproteinase-2 and -9 expression with recurrences in primary spontaneous pneumothorax patients

Primary spontaneous pneumothorax (PSP) is a common but serious disease with an incidence of 18–28/100,000/year for men and 1.2–6/100,000/year for women (1). PSP occurs without previous trauma or precipitating cause and arises in patients without clinically apparent underlying lung diseases. This disease mostly occurs in young adolescent males and is encountered in clinical practice. The incidence of ipsilateral recurrence of PSP is approximately 30%, with a range of 16–52% whilst the average rate of contralateral recurrence is around 15% after first episode of PSP (2-4)