Infection aiguë à cytomégalovirus révélatrice d’un lupus érythémateux systémique

The diagnostic role of cardiac magnetic resonance imaging in detecting myocardial inflammation in systemic lupus erythematosus. Differentiation from viral myocarditis

Objective

The objective of this paper is to evaluate the diagnostic role of cardiac magnetic resonance imaging (CMR) in detecting myocardial inflammation in systemic lupus erythematosus (SLE) and its differentiation from viral myocarditis.

Patients and methods

Fifty patients with suspected infective myocarditis (IM), with chest pain, dyspnoea or altered ECG, increase in troponin I and/or NT-pro BNP, with or without a history of flu-like syndrome or gastroenteritis and elevated C-reactive protein (CRP) within three to five (median four) weeks before admission, 25 active SLE patients, aged 38 ± 3 years, and 20 age-matched controls were prospectively evaluated by clinical assessment, ECG, echocardiogram and CMR. All patients underwent coronary angiography, and those with significant coronary artery disease (CAD) were excluded. CMR was performed using STIR T2-W (T2W), early T1-W (EGE) and late T1-W (LGE). Endomyocardial biopsies were performed when clinically indicated by current guidelines. Specimens were examined by immunohistological and polymerase chain reaction (PCR) analysis.

Results

Positive coronary angiography for CAD excluded 10/50 suspected IM and 5/25 active SLE. Positive clinical criteria for acute myocarditis were fulfilled by 28/40 suspected IM and only 5/20 active SLE. CMR was positive for myocarditis in 35/40 suspected IM and in 16/20 active SLE. Endomyocardial biopsy (EMB), performed in 25/35 suspected IM and 7/16 active SLE with positive CMR, showed positive immunohistology in 18/25 suspected IM and 3/7 active SLE. Infectious genomes were identified in 24/25 suspected IM and 1/7 active SLE.

Conclusions

CMR-positive IM patients were more symptomatic than active SLE. More than half of CMR-positive patients also had positive EMB. PCR was positive in almost all IM, but unusual in SLE. Due to the subclinical presentation of SLE myocarditis and the limitations of EMB, CMR presents the best alternative for the diagnosis of SLE myocarditis.

TLR7/8/9 polymorphisms and their associations in systemic lupus erythematosus patients from Southern Brazil

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease and can affect several organs and systems. It is characterized by high production of autoantibodies against nuclear compounds. TLR7/8/9 are responsible for nucleic acid recognition and they trigger proinflammatory responses through activation of NK-kappaB and Type I IFN production, making a bridge between the innate and the adaptative immune systems. We analyzed the frequency of TLR7 rs179008, TLR8 rs3764880, TLR9 rs5743836 and rs352140 in 370 patients with SLE and 415 healthy controls from southern Brazil. All analyses were conducted with regard to gender and ethnicity. Genotypic and allelic frequencies were different for TLR7 rs179008 (0.253 vs. 0.163, p = 0.020 and p = 0.003, OR for T allele: 1.74 CI 95% 1.12–2.70) and TLR9 rs5743836 (0.174 vs. 0.112, p = 0.045 and p = 0.017, OR for C allele: 1.59, CI 95% 0.99–2.57) between European-derived female groups. A higher frequency was observed for the presence of Anti-SSa/Ro for TRL9 rs5743836 C allele carriers (0.228 vs 0.126, Bonferroni corrected p = 0.06). No statistical differences were found for TLR9 haplotypic analyses. We suggest that TLR7 rs179008 and TLR9 rs5743836 can be considered SLE susceptibility factors for women of European descent in our population.