AB0592 NAILFOLD CAPILLARY ABNORMALITIES PREDICT INTERSTITIAL LUNG DISEASE (ILD) COMPLICATION IN SYSTEMIC SCLEROSIS PATIENTS

Abstract

Background:Systemic sclerosis (SSc) have various organ involvements including pulmonary hypertension (PH), digital ulcers (DU), and interstitial lung disease (ILD). On the other hand, Nailfold capillary (NFC) abnormalities (enlarged/giant capillaries, fresh or old hemorrhages, avascular areas, ramified/bushy capillaries) detected by capillaroscopy are included in ACR/EULAR classification criteria for SSc as one of important findings. In addition, many studies have reported the relationship between NFC abnormalities and organ involvements (DU, PH) [1][2]. However, there are a few reports about the relationship between NFC abnormalities and ILD.Objectives:We clarify the association with NFC abnormalities and ILD in SSc patients.Methods:We enrolled SSc patients without PH from January 2016 to December 2019 in our institution. SSc patients were diagnosed according to EULAR classification criteria in 2013. ILD was detected by chest CT scans. We assessed severity of ILD with pulmonary function tests (PFT). Abnormal PFT was defined as vital capacity (%VC) or diffusion capacity (DLCO) < 70%. NFC abnormalities were detected with “OptiPiX capillaroscopy Clinic 1.7.x” and the number of capillaries was measured per 1mm in 2nd to 5th fingers of both hand. We defined enlarged and giant capillaries as >30 µm and >50 µm, respectively.Results:We enrolled 59 SSc patients (54 females, 5 males). Mean age is 65.0 ± 8.0 years. Thirty-one patients (52.5%) were complicated with ILD. Mean capillary counts are 6.6/mm. The number of patients with each NFC abnormalities (enlarged capillaries, giant capillaries, microhemorrhages, ramified, avascular areas) are 42, 32, 48, 38, and 33 cases, respectively. Two cases did not have NFC abnormalities. SSc patients with giant capillaries had fewer ILD complications (p <0.05, odds ratio 0.183 [0.059 – 0.57]). Other NFC abnormalities were not associated with ILD in SSc patients. We inspected %VC of 23 patients and DLCO of 20 patients with ILD. Eleven patients had abnormal PFT (5 patients had abnormal %VC and 9 patients had abnormal DLCO). Most of them had not enlarged capillaries than patient with normal PFT (odds ratio 0.11 [0.016 – 0.81]). Other NFC abnormalities including giant capillaries were not associated with abnormal PFT.Conclusion:We investigated the relationship between NFC abnormalities and ILD conplications in SSc patients. NFC abnormalities are associated with ILD complicacion and severity of ILD. It was suggested that no giant capillary in SSc patients may predict ILD complication. Moreover, no enlarged capillary may predict the severe ILD.