3 | DISCUSSION
BD was first described by Professor Hulusi Behçet in 1937 [9]. Since then, many diagnostic criteria have been established. In 2014, the revised version of the International Criteria for Behçet’s Disease (ICBD) was proposed, and a score of ≥ 4 points corresponds to the diagnosis [1]. The pathergic test and HLA-B51 typing are not specific, and their positivity is influenced by geographical variations [4]. Our patient had oral aphthosis (2 points), genito-anal ulcerations (2 points), and vascular manifestations (1 point), fulfilling the ICBD criteria.
The age of onset of BD is relatively early. It is usually diagnosed in the second and third decades of life. Diagnosis before the age of 15 and after the age of 50 is exceptional [3,10]. In our case, the diagnosis was made at the age of 24. Both sexes can be similarly affected, but the prognosis is worse in men. In addition, cardiovascular manifestations are more common in men [3,7].
Cardiac involvement is a serious complication reported in less than 5% of cases [10]. It can manifest as pericarditis, myocarditis, endocarditis, intracardiac thrombosis, myocardial fibrosis, myocardial infarction and DCM [6]. The most common form is pericarditis. DCM is less common and can manifest as systolic or diastolic heart failure or be asymptomatic. In a study conducted in Iran, 4.3% of patients developed DCM [11,12]. Although rare, BD should not be overlooked in young adults presenting with heart failure. Signs of BD should be sought on clinical examination. In our case, special attention to bipolar aphthosis during the initial hospitalization may have led to an early diagnosis of BD.
Vascular manifestations of BD (or angio-Behçet) occur in 7 to 32% of cases. They are dominated by venous involvement, mainly deep vein thrombosis [13]. The majority of patients present with the first vascular manifestation within five years of disease onset. In 20% of cases, vascular involvement occurs simultaneously [7]. In our case, vascular lesions were discovered at the time of BD diagnosis.
Arterial involvement is less common, occurring in 5-10% of cases. The frequency is probably underestimated, as autopsy data have reported a higher proportion [10]. Arterial lesions usually present as aneurysms and rarely as thrombosis [7]. Pseudoaneurysms are most common. Arterial aneurysms are often multiple, mainly affecting the abdominal aorta and femoral arteries [10].
Involvement of the SMA is very rare, accounting for 5.5% of all visceral aneurysms [8]. A review of the literature by Kakehi et al. in 2019 found 15 cases [14]. Men were most affected. Abdominal pain was the main symptom (80%). Lesions consisted of aneurysm (11 cases), thrombosis (4 cases) and dissection (1 case) and were mostly associated with other arterial manifestations. In six patients, the discovery of SMA involvement was concomitant with the diagnosis of BD. In our case, it was an asymptomatic aneurysm of the SMA.
Pulmonary artery involvement is rare, with an overall incidence of less than 5%. It usually occurs 3 to 4 years after disease onset [6,7,15]. Pulmonary artery aneurysms are the most common, followed by pulmonary embolism. Pulmonary embolism can be isolated (3%) or associated with aneurysms (25%) [6]. In our case, pulmonary embolism was suspected four months before the diagnosis of BD. CT scans showed no direct evidence of pulmonary embolism, but pulmonary infarction and minimal pleurisy were indirect signs.
The two aneurysms associated with cardiac involvement and pulmonary embolism represent the originality of our observation. These are important complications of BD. Atherosclerosis, infection, and Takayasu’s arteritis are the main differential diagnoses for aortic involvement. The young age, low tobacco exposure, and absence of diabetes or dyslipidemia did not suggest an atheromatous origin. Infectious tests (HIV, viral hepatitis, syphilis, and tuberculosis) were negative. Classification criteria for Takayasu’s arteritis were not complete.
A multidisciplinary approach is essential for the management of cardiovascular complications. The 2018 European League Against Rheumatism (EULAR) recommendations suggest the combination of high-dose corticosteroids with cyclophosphamide in the acute phase of angio-Behçet. Surgical treatment should be performed at a later stage to reduce the risk of complications. Curative anticoagulation is recommended for venous thrombosis in the absence of pulmonary artery aneurysm [16]. There is no consensus on the treatment of cardiac involvement. The goal is to reduce inflammation to limit lesion progression and treat symptoms. The efficacy of anti-inflammatory and immunosuppressive drugs has been demonstrated [12]. However, treatment is individualized according to the patient’s age and the type and severity of complications. We chose medical management alone because the aneurysms were asymptomatic and our local technical platform does not allow us to perform vascular surgery.