Cutaneous Vasculitis in Cogan's Syndrome: A Report of Two Cases Associated with Chlamydia Infection

French protocol for diagnosis and management of Cogan's syndrome

Cogan's syndrome is a condition of unknown origin, classified as a systemic vasculitis. It is characterised by a predilection for the cornea and the inner ear. It mainly affects Caucasian individuals with a sex-ratio close to one. Ophthalmological and cochleo-vestibular involvement are the most common manifestations of the disease. The most frequent ophthalmological type of involvement is non-syphilitic interstitial keratitis. Cochleo-vestibular manifestations are similar to those of Meniere's syndrome. The disease progresses in ocular and ear-nose-throat (ENT) flares, which may occur simultaneously or in isolation. Association with other autoimmune diseases, particularly other forms of vasculitis such as polyarteritis nodosa or Takayasu's arteritis, is possible. Ocular involvement, as well as cochleo-vestibular involvement, can be inaugural and initially isolated. Onset is often abrupt. The characteristic involvement is "non-syphilitic" interstitial keratitis. It is usually bilateral from the outset or becomes so during the course of the disease. It presents as a red, painful eye, possibly associated with decreased visual acuity. Cochleo-vestibular involvement is usually bilateral from the outset. It is characterised by the sudden onset of continuous rotational vertigo associated with tinnitus, rapidly progressive sensorineural deafness. Approximately 30-70% of patients present with systemic manifestations. Deterioration in general status with fever may be present. Laboratory evidence of inflammatory syndrome is associated in 75% of cases. Cogan's syndrome is a presumed autoimmune type of vasculitis, although no specific autoantibodies have been identified. Ocular involvement is usually associated with a good prognosis, with total visual acuity recovery in the majority of cases. In contrast, cochleo-vestibular involvement can be severe and irreversible. Therapeutic management of Cogan's syndrome, given its rarity, lacks consensus since no prospective randomised studies have been conducted to date. Corticosteroid therapy is the first-line treatment. Combination with anti-TNF therapy should be promptly discussed.

A Case of Bilateral Retinal Vasculitis in Atypical Cogan Syndrome

Cogan syndrome (CS) is a rare chronic inflammatory disease characterized by ocular and inner ear inflammation. Well-known ocular manifestations include non-syphilitic interstitial keratitis (IK); however, some cases are not associated with IK. Inner ear symptoms include sensorineural hearing loss, rotatory vertigo, and tinnitus, which can become irreversible without timely treatment. Therefore, early and appropriate diagnosis and therapeutic intervention are important. However, due to its rarity, few physicians have encountered CS and early diagnosis is difficult. In this report, we present the details of the diagnosis and treatment of an atypical CS. The patient was a 44-year-old Japanese woman who was admitted to the Department of Immunology and Allergy at Itami City Hospital (Itami City, Hyogo, Japan) due to a persistent fever of approximately 40°C for nine days. Multiple erythematous lesions appeared on both lower legs, and she experienced decreased vision in her left eye. Uveitis with retinal vasculitis was observed in both eyes and the optic nerve head showed remarkable swelling in the left eye. Hearing tests revealed impaired hearing in both ears. Based on these findings, we diagnosed atypical CS and initiated systemic and topical steroid therapy. Approximately two weeks later, visual acuity and hearing levels improved. Fluorescein angiography (FA) revealed a non-perfusion area in both eyes, and retinal photocoagulation was performed using a pattern-scanning laser. Eighteen months after the laser irradiation, retinal neovascularization (RNV) was observed in the area where the laser was applied to the left eye; therefore, an additional laser was applied. Combination therapy with steroids and immunosuppressive drugs was continued until the patient's last visit three years later and she did not experience any recurrence of uveitis or hearing loss. In this case, a pattern-scanning laser was used for retinal photocoagulation to prevent RNV; however, RNV occurred within the area of the laser spots. In such cases of retinal capillary occlusion due to vasculitis, it may be better to close the spacing or use a conventional laser system. In the presence of retinal vasculitis with systemic inflammation, CS should be suspected, and a hearing test should be performed, even in the absence of subjective symptoms. Early treatment and prevention of irreversible hearing loss should be necessary. Careful follow-up in collaboration with other departments is important for CS cases.

Atypical Cogan's Syndrome Mimicking Giant Cell Arteritis Successfully Treated with Early Administration of Tocilizumab

A 49-year-old Japanese man with a 2-month history of a fever, headache, and bilateral conjunctival hyperemia was admitted. His condition fulfilled the giant cell arteritis classification criteria (new headache, temporal artery tenderness, elevated ESR) and atypical Cogan's syndrome (CS) with scleritis and sensorineural hearing loss (SNHL). The interleukin (IL)-6 serum level was extremely high. Two weeks after his insufficient response of SNHL and scleritis to oral prednisolone, we administered tocilizumab (TCZ); rapid improvements in scleritis and SNHL occurred. Early IL-6 target therapy can help prevent irreversible CS-induced sensory organ damage.

Pathogenesis of liver injury in Takayasu arteritis: advanced understanding leads to new horizons

Liver injury in Takayasu arteritis (TA) is a rare phenomenon. Most symptoms are nonspecific, and the exact pathogenesis remains to be elucidated. Early diagnosis and new treatment methods are important for an improved prognosis. A summary of the clinical information and mechanistic analyses may contribute to making an early diagnosis and development of new treatment methods. A PubMed search was conducted using the specific key words “Takayasu arteritis” and “liver” or “hepatitis” or “hepatic”. Symptoms and treatment of TA with an accompanying liver injury were reviewed retrospectively. Many factors are presumed to be involved in the mechanism of TA with liver injury, including the immune response, genes, infections, and gut microbiota. There are several lines of evidence indicating that immune dysfunction is the main pathogenic factor that triggers granuloma formation in TA patients. However, the role of genetics and infections has not been fully confirmed. Recently, the gut microbiota has emerged as an essential component in the process. We reviewed in detail the current concepts that support the complex pathogenesis of TA accompanied by liver injury, and we presented recent theories from the literature. Finally, we discussed future research directions of liver injury in TA.

Familial HLA-B*52 Vasculitis: Maternal, Atypical Cogan's Syndrome with Takayasu Arteritis-mimicking Aortitis and Filial Takayasu Arteritis

Cogan's syndrome (CS), a rare vasculitis characterized by non-syphilitic, interstitial keratitis and Ménière-like attacks, is classified into "typical" and "atypical" forms, while Takayasu arteritis (TAK) is a rare large-vessel vasculitis associated with human leukocyte antigen (HLA)-B*52. Very few cases meet both the CS and TAK classification criteria. We herein report a 53-year-old woman diagnosed with atypical CS and aortitis similar to TAK. Her 25-year-old daughter manifested TAK without symptoms of CS, and both are HLA-B*52 positive. Our case highlights the difficulties of distinguishing aortitis with atypical CS from aortitis with TAK.

New Insights on the Pathogenesis of Takayasu Arteritis: Revisiting the Microbial Theory

Takayasu arteritis (TAK) is a chronic vasculitis that mainly affects the aorta, its major branches, and the pulmonary arteries. Since the description of the first case by Mikito Takayasu in 1908, several aspects of this rare disease, including the epidemiology, diagnosis, and the appropriate clinical assessment, have been substantially defined. Nevertheless, while it is well-known that TAK is associated with a profound inflammatory process, possibly rooted to an autoimmune disorder, its precise etiology has remained largely unknown. Efforts to identify the antigen(s) that trigger autoimmunity in this disease have been unsuccessful, however, it is likely that viruses or bacteria, by a molecular mimicry mechanism, initiate or propagate the auto-immune process in this disease. In this article, we summarize recent advances in the understanding of TAK, with emphasis on new insights related to the pathogenesis of this entity that may contribute to the design of novel therapeutic approaches.