The coronavirus disease of 2019 (COVID-19) can be an infectious disease due to severe acute respiratory coronavirus 2 (SARS-CoV-2). medical diagnosis to COVID-19 was 3.9 [0.6C11.1] years. A complete of 7 sufferers (70%) needed hospitalization (amount of stay 10 [4-16] times), non-e in the intense care device. Five (50%) created pneumonia, with UK-427857 inhibitor database ARDS features in 2 sufferers. Five sufferers (50%) needed air therapy (3 of these had been on domiciliary air therapy). Clinical final result was favorable in every sufferers (desk 1 ). Desk 1 Sufferers baseline features before an infection and COVID-19 scientific picture In PAH sufferers lungs and bloodstream, ACE2 expression is normally reduced.3 Indeed, recombinant ACE2 has been proposed like a novel therapy for PAH, to reverse vasoconstriction, proliferation, and swelling.3 ACE2 is known to act as a receptor for SARS-CoV-2. Experimental studies with SARS-CoV have shown that in ACE2 knockout mice, only a very low quantity of infectious SARS-CoV disease could be recovered.4 Thus, low ACE2 levels in PAH individuals could act as a protective element at an initial infective phase, avoiding SARS-Cov-2 entrance.C Chronic pulmonary inflammation is a common finding in PAH individuals.3, 5 The immune cell types that infiltrate the lungs of PAH individuals include lymphocytes, macrophages, neutrophils, dendritic cells, and mast cells. This different immune cellular panorama in PAH lungs suggests a shift toward the adaptive immune system. Consequently, the so-called tertiary lymphoid cells is present in the vicinity of bronchioles and could limit viral illness and development.2. Attenuated lung damage: Changes in pulmonary blood circulation inherent to PAH pathophysiology or related to specific vasodilator treatment might reduce the damage inflicted to the lungs and the consequent severe hypoxemia explained in COVID-19 individuals.C An unusual dissociation between lung mechanical properties (with nearly normal compliance) and severe hypoxemia has been reported,6 suggesting irregular hyperperfusion of nonventilated areas as a consequence of impaired lung perfusion rules and hypoxic vasoconstriction.6 The basal abnormal lung perfusion present in PAH individuals could limit this abrupt perfusion imbalance toward nonventilated areas. Furthermore, chronic vasodilator treatment could prevent a severe hypoxic vasoconstriction response. In this regard, phosphodiesterase-5 inhibitors and even LHR2A antibody calcium-channel blockers have been proposed like a potential treatment for COVID-19, based on its vasodilator properties and a medical trial with sildenafil is currently ongoing (NCT:04304313).1 Thus, pulmonary vasodilator therapy of our individuals could have attenuated hypoxic vasoconstriction and have favored the air flow/perfusion balance.C ARDS is caused by a severe inflammatory response, mediated by several proinflammatory providers and cytokines (tumoral necrosis element, interleukins, or endothelin-1).5 Endothelin-1 has been shown to be involved in the pathogenesis of both ARDS and PAH. 5 Earlier reports suggest that ERAs might be useful in the treatment of ARDS, based on their beneficial effects in experimental preclinical studies.5 A total of 7 individuals (70%) in our cohort received ERAs when diagnosed with COVID-19, thus suggesting the possibility of a beneficial effect of chronic endothelin-1 blockade. Open in a separate window Number 1 Possible explanations for the benign course of COVID-19 in PAH individuals. Impaired viral entry to pulmonary cells because of the existence of tertiary lymphoid tissues and decreased ACE2 expression. Decreased lung harm because of impaired vasotonic properties also to PAH vasodilator treatment, reducing intrapulmonary shunt. Decreased inflammatory response mediated by ET-1 because of the effect of Period. ACE2, angiotensin-converting enzyme 2; CCB, calcium-channel blocker; Period, endothelin receptor antagonist; UK-427857 inhibitor database ET-1, endothelin-1; PDi, phosphodiesterase-5 inhibitor; VD/VC, vasodilatation/vasoconstriction. The scientific span of UK-427857 inhibitor database COVID-19 inside our cohort of PAH sufferers was unexpectedly advantageous. This finding could possibly be described by either the pathophysiological peculiarities of the condition or with a protective aftereffect of PAH-specific treatment. PAH therapies may possess a defensive impact in COVID-19 also, although that may only be attended to in placebo-controlled randomized managed trials. Financing J. Nuche is normally receiver of a predoctoral offer (Jordi Soler Soler) through CIBERCV. P. Escribano Subas is normally receiver of a offer.