Correspondence

Increased Number of Pulmonary Embolisms in Sarcoidosis Patients

Sarcoidosis is an independent risk factor for venous thromboembolism (VTE). However, the characteristics and clinical evolution of sarcoidosis patients presenting a VTE (sarcoidosis/VTE group) in the course of their disease are not known. Consequently, if VTE occurrence is associated with a more severe disease is still pending.

We conducted a retrospective case-control study of sarcoidosis/VTE patients compared to matched sarcoidosis controls without VTE in two French tertiary centers, analysed and compared the clinical, biological, functional, imaging and evolutive profiles of the two groups.

Sixty-one patients were included with at least one episode of VTE during course of sarcoidosis. At sarcoidosis onset (before/at the time of VTE occurrence) the number of affected organs, radiological stages and pulmonary functional tests were not significantly different between the two groups. In contrast, we found that sarcoidosis/VTE patients required more frequently a systemic immunosuppressive therapy (corticosteroids and/or immunosuppressors, 79% versus 58%; p = 0.008). The functional course was also poorer in sarcoidosis/VTE patients with a more frequent decrease in functional vital capacity (33% versus 18% in sarcoidosis/VTE patients and controls, respectively, p = 0.008). Finally, sarcoidosis/VTE patients presented more frequently with pulmonary hypertension (10% versus 1% in patients and controls, respectively, p = 0.006), and their survival was significantly worse (log-rank p <0.001).

The occurrence of VTE during sarcoidosis is associated with a more severe disease and a poorer prognosis. The occurrence of VTE during sarcoidosis might signal a more inflammatory and/or evolutive disease in sarcoidosis/VTE patients and should be taken in consideration when designing therapeutic strategies for them.

Pulmonary hypertension (PH) is a known complication of pulmonary sarcoidosis and its aetiology is unclear. Different pathophysiological mechanisms in sarcoidosis-associated pulmonary hypertension (SAPH) are known. Clinical phenotyping can aid clinicians in choosing the optimal treatment strategy. This study aimed to describe clinical phenotypes of SAPH and their characteristics.

A retrospective cohort study was performed on all SAPH patients at a tertiary referral centre. All patients were extensively analysed and discussed case by case in a multidisciplinary expert team to determine the most likely pathophysiological mechanism of PH. Patients were then classified into conceptual clinical phenotypes.

Forty (40) patients with SAPH were identified between 2010 and 2019. Three (3) patients were classified as the postcapillary phenotype. Of the remaining 37 patients with precapillary PH, six were classified as ‘compression of pulmonary vasculature’, 29 as ‘parenchymal’, one as ‘suspected vasculopathy’, and one as ‘chronic pulmonary emboli’ phenotypes. Of the patients with compression of pulmonary vasculature, four showed compression by fibrotic disease and two by active sarcoidosis-based disease. Within the parenchymal phenotype, 20 patients (69%) showed pulmonary vascular resistance >3.0 Wood Units (WU) and had significantly lower diffusing capacity of the lung for carbon monoxide compared with the nine patients (31%) with pulmonary vascular resistance ≤3.0 WU.

SAPH had multiple pathophysiological mechanisms and clinical phenotypes in this retrospective study. Further studies are necessary to examine how these phenotypes can affect appropriate treatment and prognosis.