BACKGROUND:

Chitotriosidase has been found to be useful as a sarcoidosis biomarker. In patients with better outcome lower values were observed. Some subjects have 24-base pair duplication in the chitotriosidase gene (CHIT1) that results in the production of inactive enzyme. This might influence the outcome of sarcoidosis and account for described observations.

OBJECTIVES:

The aim of this study was to correlate common CHIT1 duplication polymorphism and clinical outcome status in sarcoidosis (COS).

METHODS:

This retrospective study comprised 180 patients with sarcoidosis. COS at 3, 5 and 10 years was determined and correlated with CHIT1 24-base pair duplication polymorphism. CHIT1 genotyping was done by the PCR method.

RESULTS:

There was no significant correlation between CHIT1 24-base pair duplication polymorphism and COS at 3, 5 or 10 years but a subgroup analysis showed higher frequency of patients with Loefgren's syndrome (50% vs. 17.1%) and better COS in CHIT1 24-base pair duplication homozygotes vs. all other subjects in major COS groups (no, minimal and persistent disease) at 3 years (p=0.025) and borderline significant at 5 years (p = 0.090).

CONCLUSIONS:

In this study no correlation between CHIT1 24-base pair duplication polymorphism and COS was shown, but possible protective role of homozygous condition for CHIT1 24-base pair duplication polymorphism is suggested.