Imbalance of TH17/TREG cells in Tunisian patients with systemic sclerosis.

Fibrosis is a pathological manifestation in which connective tissue replaces normal one. It can affect many tissues from the skin to internal organs such as the lungs. Manifestations of pulmonary involvement can be pulmonary arterial hypertension or pulmonary fibrosis. The latter one is currently the leading cause of death in various autoimmune diseases, including systemic sclerosis. Our study group consists of 50 patients with systemic sclerosis: 24 with limited cutaneous form and 26 with diffuse cutaneous form. This cohort was compared to 50 healthy controls (age and sex matched); our aim is to explore the distribution of TH17 cells (TH17) as well as regulatory T cells (TREG) and study their correlation with the disease's progress. Our results show an increase for IL17A in patients compared to controls and that this increase is correlated with a specific clinical involvement: Pulmonary fibrosis. This correlation suggests a crucial role of IL17A in fibrosis especially in systemic sclerosis. In addition, we have shown that the percentages of TH17 cells are higher in patients; however, the percentages of TREG cells are similar between patients and controls. A study of TREG cell activity showed that TREG lost suppressive activity by inactivating the FOXP3 transcription factor. This proves that despite their presence, TREG does not adequately carry out their regulatory activity. Finally, we analyzed the correlation between TH17/TREG and clinical damage; the results show a positive correlation with pulmonary involvement proving the role of TH17/TREG balance in induced fibrosis in systemic sclerosis. No significative difference was observed, for all the parameters, between the two different forms of the disease. In conclusion, the results associated with the TH17/TREG scale and their correlations with fibrosis in systemic sclerosis open a way for new tools to manage this autoimmune disease, which up to today has neither treatment nor accurate diagnosis.

Characteristics of neurological manifestations of Behçet's disease: a retrospective monocentric study in Tunisia.

OBJECTIVE: The aim of the present study was to analyze demographic, clinical and genetic features of Behçet's disease patients with neurological involvement through a monocentric study of a homogenous group of hospitalized patients observed in the same department and to compare them with those of other ethnic and geographic groups. METHODS: Four hundred and thirty Behçet's disease (BD) patients were retrospectively studied. Diagnosis of BD was made according to the international study group for Behçet's disease criteria. Patients with neurological findings suggestive of involvement of the nervous system by BD were further studied according to clinical examination, laboratory tests and neuroradiological investigations. RESULTS: Neurological involvement was observed in 121 patients (28.1%). The mean age at neuro-Behçet's disease (NBD) onset was 29.7 years. Average disease duration of BD before neurological manifestations onset was 6.4 years. Male to female ratio was 1.8. Of the 121 NBD patients, parenchymal involvement occurred in 74 patients (61%). Among them 26 (21.4%) presented with brainstem involvement, 24 (19.8%) with hemispheric involvement and 2 (1.6%) with spinal cord involvement. Non-parenchymal NBD occurred in 47 patients (39%). Involvement of the main vascular structures (Vasculo-NBD) was the most common non-parenchymal NBD lesion found in 35 patients (28.9%) consisting of cerebral vein thrombosis (CVT) in 24 cases and cerebral arterial thrombosis in 11 cases. Forty-nine (40.5%) patients with NBD have been followed-up for a median of 3 years (range 1-19 years). Forty-one of them recovered well without significant residual disability, 5 patients made no improvement and are left with severe neurological impairments and 3 died. Male gender and CNS parenchymal lesions occurrence were significantly associated with a poorer prognosis. CONCLUSION: Clinical and epidemiological features of NBD are various. In our Tunisian cohort of NBD patients the main characteristic features were male predominance, a relatively high prevalence of CVT, a low prevalence of intra-cranial hypertension and a significant lower frequency of HLA-B51 haplotype.