From bilateral pulmonary embolism to the final diagnosis of Behçet's disease: a rare case report.

BACKGROUND

Behçet’s disease (BD) is a chronic, relapsing multisystem vasculitis that most frequently presents with recurrent oral and genital ulcers, ocular involvement, and skin lesions. Vascular complications are well recognized, but pulmonary embolism (PE) is an uncommon manifestation, despite the high prevalence of venous thrombosis in BD. When it occurs, PE can be life-threatening and poses significant diagnostic and therapeutic challenges. CASE PRESENTATION: A 38-year-old male with no prior comorbidities presented with recurrent hemoptysis, fever, and systemic symptoms of several months’ duration. Initial laboratory tests, chest CT, HRCT, and bronchoscopy with bronchoalveolar lavage (BAL) revealed no specific findings, and tuberculosis was excluded through negative acid-fast bacilli smear, culture, and PCR. Despite an extensive work-up, recurrent hemoptysis persisted. CT pulmonary angiography unexpectedly demonstrated bilateral pulmonary emboli, disproportionate to the relatively mild clinical presentation. Further rheumatologic evaluation revealed a genital scar and recurrent painful oral lesions, fulfilling the clinical criteria for BD. Immunologic and serologic tests, including HLA-B51, ANA, ANCA, anti-dsDNA, C3, and C4, were all negative, and ophthalmologic examination showed no ocular involvement. The patient was treated with high-dose intravenous methylprednisolone followed by azathioprine as maintenance therapy, along with apixaban for anticoagulation. During follow-up, recurrent oral ulcers, folliculitis/pseudofolliculitis, and erythema nodosum developed, which further supported the diagnosis.

CONCLUSION

This case highlights pulmonary embolism as a rare but severe manifestation of BD that may precede classical mucocutaneous features. It emphasizes the importance of thorough history-taking and physical examination when laboratory and imaging results are inconclusive. Early recognition of BD in patients with unexplained pulmonary embolism is essential, as timely initiation of immunosuppressive and anticoagulant therapy can improve outcomes and prevent life-threatening complications. TRIAL REGISTRATION: Not applicable.