Utility of computed tomography in differentiation between different groups of pulmonary hypertension in SLE patients

Abstract

Background
Pulmonary hypertension (PH) is a serious and potentially life-threatening complication of systemic lupus erythematosus (SLE). Its etiology in SLE is heterogeneous and includes vasculopathy, interstitial lung disease (ILD), left-sided heart dysfunction, and chronic thromboembolic disease. High-resolution computed tomography (HRCT) plays an important role in defining phenotypes and supporting targeted management.


Methods
This analytical cross-sectional study included 60 adults with SLE and echocardiograph-confirmed PH. All patients underwent clinical evaluation and HRCT. Radiologic patterns were evaluated and correlated with pulmonary hypertension subtypes based on the 2022 ESC/ERS classification. We used SPSS v20 to analyze the data, and chi-square and Fisher’s exact tests were used to look for connections.


Results

In our cohort of patients with SLE and confirmed pulmonary hypertension, the most prevalent subtype observed was Group 2 PH, attributed to underlying left-sided heart disease (48.3%). This was followed by pulmonary arterial hypertension (25%), PH due to lung disease/hypoxia (20%), and chronic thromboembolic PH (6.7%). HRCT findings differed significantly among PH groups using Fisher’s Exact Test (
p
 < 0.05). Normal HRCT scans were most frequent in Group 1, lung congestion with septal thickening predominated in Group 2 (
p
 = 0.049), nonspecific interstitial pneumonia (NSIP)—a pattern of interstitial lung disease—was strongly associated with Group 3 (
p
 < 0.000001), and all Group 4 patients demonstrated pulmonary embolism on Computed Tomography Pulmonary Angiography (CTPA) (
p
 < 0.00001).



Conclusion
HRCT patterns vary markedly across PH subtypes in SLE and provide important diagnostic clues to the underlying pathophysiological mechanism. HRCT provides important phenotypic information that supports noninvasive classification of SLE-associated pulmonary hypertension and helps guide further diagnostic and management pathways.