Pulmonary vasculitis in Hughes-Stovin syndrome (HSS): a reference atlas and computed tomography pulmonary angiography guide—a report by the HSS International Study Group

Abstract

Introduction Hughes-Stovin syndrome (HSS) is a systemic vasculitis characterized by widespread venous/arterial thrombosis and pulmonary artery aneurysms (PAAs), which is associated with serious morbidity and mortality. All fatalities reported in HSS resulted from unpredictable fatal suffocating hemoptysis. Therefore, it is necessary to recognize pulmonary complications at an early stage of the disease. Objectives The aims of this study are to develop a reference atlas of images depicting the characteristic features of HSS by computed tomography pulmonary angiography (CTPA). To make a guide for physicians by developing a classification of PAAs according to the severity and risk of complications associated with each distinct lesion type. Methods The Members of the HSS International Study Group (HSSISG) collected 42 cases, with high-quality CTPA images in one radiology station and made reconstructions from the source images. These detailed CTPA studies were reviewed for final image selection and approved by HSSISG board members. We classified these findings according to the clinical course of the patients. Results This atlas describes the CTPA images that best define the wide spectrum of pulmonary vasculitis observed in HSS. Pulmonary aneurysms were classified into six radiographic patterns: from true stable PAA with adherent in-situ thrombosis to unstable leaking PAA, BAA and/or PAP with loss of aneurysmal wall definition (most prone to rupture), also CTPA images demonstrating right ventricular strain and intracardiac thrombosis. Conclusion The HSSISG reference atlas is a guide for physicians regarding the CTPA radiological findings, essential for early diagnosis and management of HSS-related pulmonary vasculitis. Key Points• The Hughes-Stovin syndrome (HSS) is a systemic vasculitis characterized by extensive vascular thrombosis and pulmonary artery aneurysms (PAAs) that can lead to significant morbidity and mortality.• All fatalities reported in HSS were related to unpredictable massive hemoptysis; therefore, it is critical to recognize pulmonary complications at an early stage of the disease.• The HSS International Study Group reference atlas classifies pulmonary vasculitis in HSS at 6 different stages of the disease process and defines the different radiological patterns of pulmonary vasculitis notably pulmonary artery aneurysms, as detected by computed tomography pulmonary angiography (CTPA).• The main aim of the classification is to make a guide for physicians about this rare syndrome. Such a scheme has never been reached before since the first description of the syndrome by Hughes and Stovin since 1959. This classification will form the basis for future recommendations regarding diagnosis and treatment of this syndrome.

Clinical presentation, radiological findings and treatment options in Hughes-Stovin syndrome

“…Therefore, helical CT can be effective for the diagnosis [ 7 , 16 ]. Magnetic resonance angiography can be an alternative for the diagnosis but is less sensitive than helical CT for small aneurysms [ 11 , 14 , 26 – 28 ].…”

“…Computed tomography pulmonary angiography is considered the gold standard imaging technique for the pulmonary involvement in HSS. To best describe radiological findings in CTPA, the HSS International Study Group (HSSISG) published a comprehensive reference atlas of CTPA images to illustrate the broad range of CTPA manifestations described in HSS [ 28 ].…”

Hughes-Stovin syndrome (HSS): current status and future perspectives

“…Early signs of vasculitis in HSS present themselves as aneurysmal wall enhancement on post-contrast phase CTPA-acquired images [10]. Stable aneurysmal disease is characterized by a contrast-filled dilation in the pulmonary artery (or a variably sized marginal hypodense peri-aneurysmal component in pseudo-aneurysmal disease) as well as the lobar/segmental bronchial branches [10].…”

“…Early signs of vasculitis in HSS present themselves as aneurysmal wall enhancement on post-contrast phase CTPA-acquired images [10]. Stable aneurysmal disease is characterized by a contrast-filled dilation in the pulmonary artery (or a variably sized marginal hypodense peri-aneurysmal component in pseudo-aneurysmal disease) as well as the lobar/segmental bronchial branches [10]. Unstable aneurysmal disease is characterized by signs of extra-luminal leakage, such as loss of aneurysmal wall definition and peri-aneurysmal ground-glass opacification/consolidation with possible signs of air bronchograms (dark air-filled bronchi being made visible by the opacification of surrounding alveoli) [10].…”

“…Pathobiological pathways are unknown so far, but clearly anticoagulation in the later stages may be fatal, whereas urgent surgical interventions may be needed. Physicians will have to make a choice between the following palettes [10]: urgent vascular intervention (aneurysmorrhaphy/aneurysmectomy, segmentectomy/lobectomy, in cases of distal PAA) when potentially instable (pseudo)aneurysms are found, anticoagulation when thromboembolism is found versus anti-inflammatory regimens when vasculitic lesions are found, and possibly arterial dilatators when pulmonary arterial hypertension is detected. Our pathogenetic understanding often starts with description and imaging, so for the sporadic HSS a promising start now has been made by the international task force.…”