Manifestations thoraciques des maladies de Behçet et de Takayasu

[Thoracic manifestations of Behcet's disease]

Behcet's disease (BD) is a multisystemic vasculitis involving arteries and veins of all sizes. While joint and dermatological manifestations are the most common features of BD and are associated with a good prognosis; vascular involvement, remains the principal cause of death. Arterial manifestations occur in 5-10% of cases and manifest as occlusion/thrombosis or aneurysms. Arterial aneurysms are likely multiple and the most common sites are pulmonary arteries, aorta and arteries of lower limbs. Parenchymal involvement is less frequent and may manifest as consolidation or nodules, which may evolve to excavation. Aneurysms may occur at the sites of arterial puncture; then, non-traumatic techniques are favored. Patients with arterial manifestations may present with fever and increased inflammatory markers. Artery damage is rare, serious, and may result in massive hemoptysis. The prognosis of pulmonary artery aneurysms is severe (mortality estimated up to 26%) but has been improved by earlier diagnosis and the introduction of immunosuppressants. Treatment of severe arterial manifestations is based on high-dose corticosteroids along with cyclophosphamide or anti-TNF antagonists. Anticoagulation could be added to immunosuppressants in case of venous thrombosis if a coexisting pulmonary aneurysm is ruled out. Endovascular treatment should be performed in case of severe symptomatic pulmonary aneurysms, along with an adequate medical management. Long-term maintenance therapy of these severe forms is of paramount importance because of relapse risk (40% at five years).

Coeliac artery dissection as a rare manifestation of Behcet's disease

Behcet's disease is a multisystemic vasculitis. Arterial involvement in the form of acute dissection is rare. A 42-year-old Lebanese man with Behcet's disease presented with severe abdominal pain. On exam, blood pressure was 162/104 mm Hg, and he exhibited epigastric tenderness. CT angiogram demonstrated an acute dissection of the coeliac artery trunk, common hepatic artery and proper hepatic arteries, with asymmetric thickening of the proximal left subclavian artery and circumferential thickening of the abdominal infrarenal aorta suggestive of vasculitis. Treatment included intravenous clevidipine, nitroprusside and methylprednisolone, which transitioned to oral metoprolol, amlodipine and prednisone. He responded well. Arterial dissections have been described with Behcet's. We report a coeliac artery aneurysm in association with a flare of Behcet's disease. Arterial wall inflammation combined with the sheering forces of hypertension likely predisposes to arterial dissection.

NOD2 is highly expressed in Behçet disease with pulmonary manifestations

Background

Excessive Th1 cells and TLRs functions are involved in the pathogenesis of Behcet's disease (BD) in response to bacterial antigens. NOD2, an intracellular pathogen recognition sensor, modulates innate defence to muropeptides derived from various bacterial species. To further define a role for NOD2 in BD, we analysed NOD2 transcriptional responses in BAL-MNC from BD patients with pulmonary manifestations.

Methods

We analysed NOD1, NOD2, T-bet and TLRs mRNA expression with real-time polymerase chain-reaction in BAL cells obtained from 23 BD patients with pulmonary manifestations and their matched controls.

Results

We found that NOD2 mRNA expression was highly up-regulated in BAL cells from BD and sarcoidosis patients compared to healthy control group (P = 0.001). In BD patients, significant correlation was found between NOD2 and T-bet mRNA expression (r = 0.602; P = 0.0009). In BAL from BD patients, NOD2 and T-bet mRNA expression were significantly correlated with BAL-lymphocytes (r = 0.485, P = 0.010; r = 0684, P = 0.0001 respectively). NOD2 in BD was also correlated with TLR 2(r = 0.444; P = 0.021) and TLR 4 (r = 0.574; P = 0.001) mRNA expression.

Conclusion

Our results indicate that BAL-MNC from BD patients expressed NOD2 as a result of lung inflammation. TLRs and NOD2 synergize for the induction of proinflammatory cytokines. BAL inflammatory cells showed an increased Th1 situation as indicated by increased T-bet mRNA expression.

[Acute interstitial pneumonia: diagnostic approach and management]

Acute interstitial pneumonia (AIP) encompasses a spectrum of pulmonary disorders characterized by involvement of the lung interstitium and distal airways (bronchioles and alveoli). The onset of respiratory symptoms is acute, most often within two weeks. Most AIP take place de novo, but sometimes represent an acute exacerbation of chronic lung disease. The clinical presentation of AIP comprises rapidly progressive dyspnoea, associated sometimes with cough, fever, myalgia and asthenia. Chest radiography shows diffuse pulmonary opacities. The associated hypoxemia may be severe enough to cause acute respiratory failure. Underlying aetiologies are numerous and variable, particularly in relation to the underlying immune status of the host. Various histopathological entities may be responsible for AIP although diffuse alveolar damage is the predominant pattern. The diagnostic approach to a patient presenting with AIP is to try to determine the most likely underlying histopathological pattern and to search for a precise aetiology. It relies mainly on a meticulous clinical evaluation and accurate biological investigation, essentially guided by the results of bronchoalveolar lavage performed in an area identified by abnormalities on high resolution computed tomography of the lungs. Initial therapeutic management includes symptomatic measures, broad-spectrum antibiotic treatment adapted to the clinical context, frequently combined with systemic corticosteroid therapy.

[Takayasu arteritis in southern Tunisia: a study of 29 patients]

OBJECTIVES

This study aimed to assess the clinical, laboratory, and radiological features and course of Takayasu arteritis in Tunisia.

METHODS

This retrospective study analyzed 29 patients with Takayasu arteritis between 1996 and 2006 who met the criteria for inclusion proposed by the American College of Rheumatology (ACR).

RESULTS

The file review identified 25 women and 4 men, with a mean age at diagnosis of 35.4 years (range: 18-65 years). Our series included 93% with involvement of the aortic arch and its branches, while only 24% involved renal arteries and 21% the abdominal aorta. We had no case with cardiac or pulmonary involvement. In all, 67.7% had type I disease, 10.7% type IIb, 3.6% type IV and 25% type V. Hypertension was recorded in 38%. No tuberculosis was observed. In all, 22 patients (75.8%) had glucocorticoid treatment, and 5 (17.2%) needed immunosuppressive therapy. Two patients with renal artery stenosis had endoluminal angioplasty and four patients (13.7%) required surgical intervention. Our patients were followed for a mean period of 80 months. Disease remained stable in 18 patients (64.2%).

CONCLUSION

The clinical manifestations, angiographic data and course of our patients were similar to those in other reported series. We found no relation between Takayasu arteritis and tuberculosis.

Tumor Necrosis Factor Gene Polymorphisms in Tunisian Patients With Behçet’s Disease

Behcet's disease (BD) is an inflammatory disorder that is mainly characterized by recurrent oral and genital ulcers, skin lesions, and uveitis. Recent reports focused on the genetic factors of susceptibility to this disease and especially the TNF in view of the major role played by this proinflammatory cytokine in the lesional process of Behcet's disease. In this report, we investigated the possible association between Behcet's disease and the TNF-alpha gene promoter polymorphisms -1031T/C, -308A/G, and the TNF-beta polymorphism +252A/G in Tunisian population. We compared the distribution of these polymorphisms between 89 BD patients and 157 healthy controls using polymerase chain reaction restriction fragment length-polymorphism (PCR-RFLP) analysis. The frequency of the TNF-alpha -1031C allele was significantly higher in Behcet's patients than in healthy controls (p = 0.015; chi(2) = 5.84; OR = 1.65; 95% CI = 1.08-2.54), whereas the frequencies of the TNF-alpha -308G and the TNF-beta +252G alleles were similar in the two compared groups. These results suggest that the variability of the TNF-alpha -1031T/C polymorphism can be associated with the susceptibility to Behcet's disease in our study group. Therefore, the TNF molecule may have an important genetically and/or functionally implication in the pathogenesis of BD in the Tunisian population.

Discrepancies of NKT cells expression in peripheral blood and in cerebrospinal fluid from Behçet's disease

The precise role of natural killer T (NKT) cells in the pathogenesis of Behçet's disease (BD) remains unknown. The frequency, cytokine profile and heterogeneity of NKT cells were studied in peripheral blood mononuclear cells (PBMC) from 42BD patients and in cerebrospinal fluid (CSF) samples from 9 neuro-BD patients. Flow cytometry revealed a decreased frequency of NKT cells in PBMC from BD patients (median: 0.06%; range: 0%-0.3%) when compared to healthy controls (median: 0.23%; range: 0.1%-0.7%; P<0.01). NKT cells were biased toward a Th(1)-like phenotype, with a significant decrease of IL-4/IFN-gamma ratio in BD (median: 0.049; range: 0.01-0.13) vs. healthy controls (median: 0.82; range: 0.4-1.33; P<0.01). NKT cells were increased in CSF-BD samples (median: 0.18%; range: 0.1%-0.4%), when compared to CSF-NIND patients (median: 0.05%; range: 0.01%-0.09%; P<0.01). Based on the reactivity of PBMC-derived NKT cells toward alpha-galactosylceramide (alpha-GalCer), 80% of BD patients were non-responsive. At the opposite, the reactivity of NKT cells in CSF from BD patients was not impaired. BD-CSF NKT cells exhibited an increased expression of IFN-gamma-producing cells, demonstrating that CSF-NKT cells were functional, and biased toward a Th(1)-like phenotype. These data suggest that functional NKT cells are recruited into BD inflammatory sites contributing to BD pathogenesis.