Cogan's syndrome: new therapeutic approaches in the biological era.

INTRODUCTION: Cogan's syndrome (CS) is a rare autoimmune disease, characterized by ocular and vestibulo-auditory involvement. Treatment of CS could be challenging, and the only evidence-based data comes from case reports or series. AREAS COVERED: There have recently been several reports of new treatment strategy involving the use of biological disease-modifying anti-rheumatic drugs such as TNFα inhibitors, anti-CD20 or anti-IL6 receptor antibodies, in cases resistant to first- or second-line drugs. EXPERT COMMENTARY: Corticosteroids are the cornerstone of CS therapy at disease onset and during acute phases of the disease. Conventional immunosuppressive therapy, such as methotrexate, could be used in relapsing patients or as a glucocorticoid sparing agent, but efficacy is often modest. The anti-TNFα monoclonal antibody Infliximab appears to be the most frequently used, leading to an improvement in hearing loss in 89% of the cases and allow corticosteroid tapering in 86% of the patients. The appropriate timing of Infliximab treatment has yet to be thoroughly investigated, but it seems to be more effective when started at an early stage of the disease. Efficacy of others anti-TNFα agents is controversial. Rituximab and Tocilizumab are a safe option, but results on hearing loss have still to be confirmed on larger patients' cohorts.

Cogan syndrome: An autoimmune eye and ear disease with systemic manifestations.

Cogan syndrome (CS) is a rare vasculitis seen primarily in young adults. It predominantly affects eyes, ears and the heart with characteristic findings of interstitial keratitis, sensorineural hearing loss and vestibular dysfunction. A high index of suspicion is required to diagnose this rare disorder. It is one of the few vasculitis which can involve vessels of all sizes: small, medium and large. Coexistence of inflammatory bowel disease (IBD) in Cogan syndrome has been described in the literature. Immunosuppressive agents such as corticosteroids with or without steroid sparing agents are the standard of care. Early diagnosis and treatment are the cornerstone of treatment to prevent permanent damage to the ears and eyes. We describe a patient with Cogan syndrome with large vessel vasculitis and IBD. Our patient was treated with glucocorticoids and methotrexate.

Cogan's syndrome with pyoderma gangrenosum: management of two uncommon disorders with aggressive presentation in a patient.

Pyoderma gangrenosum (PG) coexisting with Cogan's syndrome (CS) is uncommon, although cutaneous manifestations are known to develop in CS. A middle-aged white female patient had chronic relapsing PG requiring ciclosporin and prednisolone. Despite receiving optimal doses of ciclosporin and prednisolone, she developed acute vestibulo-auditory symptoms as a result of CS. Ciclosporin was switched to methotrexate and prednisolone was increased. However, she continued to develop acute scleritis, requiring methylprednisolone pulses, and still had further flares of PG. Her methotrexate was held off when she developed severe pneumonia and she then received a trial of intravenous immunoglobulins (IVIG) for her recurrent leg ulcers. Unfortunately, she failed to respond to IVIG. Her ulcers eventually responded to six doses of monthly intravenous cyclophosphamide induction. Although CS is not an antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis, we used pulse cyclophosphamide, based on the experience of cyclophosphamide efficacy in severe ANCA-associated vasculitis (AAV). Following induction, both diseases currently remain under control with azathioprine as maintenance treatment.

Congenital heart block and immune mediated sensorineural hearing loss: possible cross reactivity of immune response.

Immune-mediated sensorineural hearing loss may complicate systemic autoimmune diseases. We have previously reported the presence of antibodies directed against inner ear antigens in patients with Cogan syndrome, a disease characterized by sudden hearing loss and interstitial keratitis. Such autoantibodies cross-react with an epitope of SSA/Ro60 protein. Anti-Ro/SSA antibodies in pregnant women cross the placenta and reach the fetal tissues inducing an immune-mediated damage of the cardiac conduction system. We wanted to evaluate whether mothers with anti-Ro/SSA antibodies who gave birth to children with congenital heart block have antibodies directed against inner ear antigens and whether these antibodies are connected with the presence of immune-mediated sensorineural hearing loss. We did not find anti-inner ear antibodies in the majority of the mothers. On the contrary a 13-year-old boy with congenital heart block and sensorineural hearing loss was positive for the presence of anti-inner ear antigens antibodies. Moreover his serum was positive for the presence of anti-Ro60 peptide antibodies but did not recognize the entire protein Ro60 (TROVE2), a behaviour similar to that of sera from patients with Cogan syndrome. In conclusion the data obtained so far show that anti-inner ear antibodies do not recognize the entire protein TROVE2 and do not support the hypothesis that such antibodies may be involved in the pathogenesis of congenital heart block.

COGAN'S SYNDROME.

OBJECTIVES: The objective of our study was to review the current knowledge on Cogan's syndrome, including etiology, diagnosis and treatment. Systematic review methodology: Relevant publications on Cogan's syndrome from 1945 to 2014 were studied. CONCLUSIONS: Cogan's syndrome is a rare autoimmune vasculitis, with unknown pathogenesis. Infection was thought to have played a role in the pathogenesis of the disease, but now the autoimmunity hypothesis is considered more likely to be true. Cogan's syndrome is characterized by ocular and audiovestibular symptoms similar to those of Meniere's syndrome. Approximately 70% of the patients have systemic disease, of which vasculitis is considered the pathological mechanism. Corticosteroids are the first line of treatment; multiple immunosuppressive drugs were also used with varying degrees of success. The novelty in the treatment of the disease is tumor necrosis factor (TNF)-alpha-blockers, but more studies are necessary to establish their efficacy.

Cogan and Behcet syndromes.

Cogan and Behcet syndromes are considered large vessel vasculitides. Both are rare diseases, with varied clinical manifestations affecting multiple organ systems. Although both have hallmark symptoms (ocular and vestibuloauditory inflammation in Cogan syndrome and aphthous ulcers in Behcet syndrome), neither has confirmatory diagnostic testing. Delayed diagnosis can result in poor outcomes. In both syndromes, large vessel arterial inflammation may result in severe morbidity and mortality. Treatment strategies in both syndromes vary based on organ system involvement and severity of manifestations. In this article, the epidemiology, proposed pathogenesis, manifestations, and the most current treatment paradigms for these syndromes are reviewed.

Cogan's syndrome: anti-Hsp70 antibodies are a serological marker in the typical form.

BACKGROUND: Cogan's syndrome (CS) is a rare autoimmune vasculitis characterized by ocular inflammation and sensorineural hearing loss. CS is divided into a "typical" form with non-syphilitic interstitial keratitis and audiovestibular symptoms, and an "atypical" form with ocular involvement affecting structures other than the cornea. Anti-Hsp70 antibodies were found at variable levels in patients presenting with various forms of autoimmune sensorineural hearing loss (ASNHL). OBJECTIVES: To assess the correlation between anti-Hsp70 antibodies and specific ASNHL subgroups. METHODS: We divided 112 subjects into four groups: 14 subjects with typical CS, 24 with atypical CS, 55 with ASNHL, and 19 control subjects (healthy subjects and patients with systemic autoimmune diseases but no sensorineural hearing or audiovestibular alterations). Patients were tested for serological autoimmunity markers including anti-Hsp70. RESULTS: Positivity of the anti-Hsp70 antibody test was highest in the typical CS group (92.9%) and lowest in the control group (5.2%). The test was positive in 52.7% of patients in the ASNHL group and 16.6% in the atypical CS group. The paired comparison analysis between groups showed that sensitivity of anti-Hsp70 in the typical CS group was significantly higher, as compared to the other three study groups. CONCLUSIONS: Anti-Hsp70 antibodies can be considered a serological marker of "typical" CS. "Atypical" CS is conceivably a sort of "melting pot" of different forms of autoimmune diseases still characterized by ocular inflammation and sensorineural hearing loss but whose antigenic characteristics need to be further defined.