PDZK1IP1 and pulmonary arterial hypertension: Guo et al. [117] demonstrated higher titres of anti-ETAR antibodies in SLE patients complicated by PAH vs. those in SLE patients without PAH (41.5% vs. 17.1%, respectively), with a correlation between the anti-ETAR titres and the sPAP value measured by echocardiography and RHC.