Cogan's Syndrome: An Audiovestibular, Ocular, and Systemic Autoimmune Disease

Assessment of Coronary Microvascular Dysfunction in Patients with Systemic Vasculitis

INTRODUCTION

Coronary microvascular dysfunction (CMD) is characterized by impaired coronary blood flow in the absence of obstructive coronary artery disease. CMD primarily involves the microvasculature, leading to myocardial ischemia, angina, and increased cardiovascular risk. Systemic vasculitides (e.g., giant cell arteritis, antineutrophil cytoplasmic antibody-associated vasculitis, and Takayasu arteritis) are a group of autoimmune conditions known to affect the vasculature through inflammation of the blood vessels that have been associated with more prevalent and severe CMD. Although systemic inflammation likely plays a role in the increased risk of cardiovascular events, the underlying pathogenesis is not well understood.

PURPOSE OF REVIEW

Invasive and non-invasive techniques for assessing coronary microvascular function have been developed to assess for blood flow and coronary flow reserve (CFR), defined as the ratio of the maximum achievable blood flow during stress to the resting blood flow. The purpose of this review is to further explore the relationship between vasculitis and CMD as well as the techniques available for assessing this association.

RECENT FINDINGS

Studies have shown that CMD is significantly more prevalent in patients with systemic vasculitis compared to the general population. Moreover, in the absence of significant atherosclerotic burden, patients with vasculitis have a lower CFR than controls, indicating more severely impaired coronary vasomotor function. This suggests that systemic inflammation itself is a factor in driving coronary vasomotor abnormalities and CMD development. CMD contributes to cardiovascular morbidity in patients with systemic vasculitis, underscoring the need for early recognition and management. Further studies are needed to determine whether therapies targeting the reduction of systemic inflammation can lead to improved coronary microvascular function and cardiovascular outcomes.

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.

Cogan syndrome: a case report and review of the literature

Cogan syndrome is a rare disease whose etiology is still undetermined. It typically affects men and women between the second and fourth decade of life. We report a case of Cogan syndrome with ocular and audio-vestibular involvement as a systemic manifestation in a 31-year-old woman.

Spectrum of Large and Medium Vessel Vasculitis in Adults: Primary Vasculitides, Arthritides, Connective Tissue, and Fibroinflammatory Diseases

PURPOSE OF REVIEW

To provide a comprehensive overview of the spectrum of large and medium vessel vasculitis in adults with primary vasculitides, arthritides, connective tissue, and fibroinflammatory diseases as well as vasculitis mimics, for an efficient differential diagnosis and initial diagnostic approach.

RECENT FINDINGS

Imaging has had a tremendous impact on the diagnosis of medium to large vessel vasculitis, now often replacing histopathologic confirmation and identifying new disease manifestations (e.g., intracranial disease in giant cell arteritis; vascular manifestations of IgG4-related disease). Novel diseases or syndromes involving blood vessels have been described (e.g., VEXAS-Syndrome with polychondritis). The use of the terms "medium" or "large" vessel varies considerably between medical specialties. The differential diagnosis of large and medium vessel vasculitis is becoming increasingly complex as new entities or disease manifestations of known inflammatory rheumatic diseases are regularly identified. A more precise and widely recognized definition of the vessel sizes would make future research more comparable.

[Atypical Cogan syndrome as a differential diagnosis of sudden sensorineural hearing loss]

Cogan I syndrome is a rare disease consisting of vestibulocochlear symptoms and non-syphilitic interstitial keratitis. Although this disease was first described in 1945, its pathogenesis is still unknown. An autoimmune vasculitis etiology is currently discussed. Atypical manifestations are characterized by delayed ocular symptoms or variability of inflammatory eye symptoms. Physical examination often reveals bilateral sensorineural hearing loss. Intratympanic corticosteroid application can be successful.

Development of a biomarker database toward performing disease classification and finding disease interrelations

A biomarker is a measurable indicator of a disease or abnormal state of a body that plays an important role in disease diagnosis, prognosis and treatment. The biomarker has become a significant topic due to its versatile usage in the medical field and in rapid detection of the presence or severity of some diseases. The volume of biomarker data is rapidly increasing and the identified data are scattered. To provide comprehensive information, the explosively growing data need to be recorded in a single platform. There is no open-source freely available comprehensive online biomarker database. To fulfill this purpose, we have developed a human biomarker database as part of the KNApSAcK family databases which contain a vast quantity of information on the relationships between biomarkers and diseases. We have classified the diseases into 18 disease classes, mostly according to the National Center for Biotechnology Information definitions. Apart from this database development, we also have performed disease classification by separately using protein and metabolite biomarkers based on the network clustering algorithm DPClusO and hierarchical clustering. Finally, we reached a conclusion about the relationships among the disease classes. The human biomarker database can be accessed online and the inter-disease relationships may be helpful in understanding the molecular mechanisms of diseases. To our knowledge, this is one of the first approaches to classify diseases based on biomarkers. Database URL:  http://www.knapsackfamily.com/Biomarker/top.php.

Beyond Giant Cell Arteritis and Takayasu's Arteritis: Secondary Large Vessel Vasculitis and Vasculitis Mimickers

PURPOSE OF REVIEW

To provide an overview of mimickers of large vessel vasculitis (LVV), by the main presenting manifestation, i.e., systemic, vascular, and cranial manifestations.

RECENT FINDINGS

The main differential diagnoses in patients with giant cell arteritis (GCA) and Takayasu arteritis (TAK) presenting with systemic manifestations (i.e., fever, anorexia, weight loss, night sweats, arthralgia/myalgia, and/or increased inflammatory indexes) are neoplastic, infectious, or other inflammatory conditions. In patients with vascular manifestations (such as peripheral ischemia, vascular stenoses, or aneurysms), atherosclerosis and non-inflammatory vascular diseases should be excluded. In those presenting with predominant cranial symptoms (i.e., temporal headache, jaw claudication, scalp tenderness, transient or permanent vision loss), other causes of headache, cerebrovascular accidents, optic neuropathy, and neuromuscular syndromes need to be considered. The diagnosis of LVV maybe challenging, especially when patients present with atypical or incomplete clinical forms. In these cases, a multidisciplinary approach is strongly recommended.

Fever of unknown origin: a challenging case

We report a case of Cogan’s syndrome presenting as fever of unknown origin in a 31-year-old woman who was admitted to the hospital with a 7-week history of fever, night sweats and other constitutional symptoms. The diagnosis remained elusive despite numerous investigations, and the patient subsequently developed rash, episcleritis, dizziness and sensorineural hearing loss. While initially thought to be a postinflammatory response to a previous infection, confirmation of the rash as a vasculitis together with the audiovestibular and ocular involvement led to a clinical diagnosis of Cogan’s syndrome. This was further corroborated by resolution of her symptoms once immunosuppressive therapy was instituted. Early recognition of Cogan’s syndrome is crucial to reducing the risk of serious complications through the timely initiation of treatment.

Rituximab Not Effective for Hearing Loss in Cogan's Syndrome

Importance. Rituximab was not effective in ameliorating the hearing loss in a patient with atypical Cogan's syndrome. Observations. We report the case of a patient who developed acute bilateral uveitis and sensorineural hearing loss. A diagnosis of atypical Cogan's syndrome was made. The patient's hearing loss did not improve despite high dose steroids and azathioprine. Rituximab was administered given a recent report of its efficacy in a patient with refractory disease; however, our patient's hearing loss did not improve. Conclusion. Hearing loss in Cogan's syndrome is difficult to treat. Though rituximab was ineffective in our case, earlier administration in the disease course could be effective for future patients.

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.

SEROUS NEUROSENSORY RETINAL DETACHMENT ASSOCIATED WITH ATYPICAL COGAN SYNDROME: A CASE REPORT

PURPOSE

To present a case of a 71-year-old woman with possible focal choroiditis and secondary serous neurosensory retinal detachment associated with atypical Cogan syndrome.

METHODS

Retrospective case report.

RESULTS

On initial evaluation, the patient had decreased vision with photopsias and distortion in the affected eye. Her history revealed 3 years of preexisting neurosensory hearing loss and corneal scarring in the affected eye. Examination findings were significant for unilateral interstitial keratitis and focal macular neurosensory retinal detachment. Fluorescein and indocyanine green angiography demonstrated focal macular leakage and staining. Treatment with intravitreal and periocular steroid injections resulted in complete resolution of the subretinal fluid and visual improvement.

CONCLUSION

Posterior segment manifestations associated with Cogan syndrome are exceedingly rare. This is the first known case of a serous neurosensory retinal detachment from suspected choroidal inflammation associated with Cogan syndrome. Prompt recognition and treatment with corticosteroids may result in anatomical and functional visual improvement, as in this case.

Interstitial Keratitis, Vertigo, and Vasculitis: Typical Cogan's Syndrome

Cogan's syndrome (CS) is a chronic inflammatory disorder of unknown etiology that most commonly affects young adults. Clinical hallmarks are bilateral interstitial keratitis and vestibuloauditory dysfunction. Association between CS and systemic vasculitis as well as aortitis also exists. The diagnosis of CS is based upon presence of characteristic inflammatory eye disease and vestibuloauditory dysfunction. We describe classic Cogan's syndrome in a 47-year-old female from Ardabil. The patient was admitted with headache, vertigo, nausea, vomiting, right leg claudication, musculoskeletal pains, bilateral hearing loss, and blindness for the past two months. Ophthalmologic examination revealed that visual acuity was 0.1 bilaterally. Conjunctival hyperemia, bilateral cataract, and interstitial keratitis were detected with a slit lamp examination. Pure tone audiogram (PTA) and auditory brain stem response (ABR) showed bilateral sensorineural hearing loss. The other differential diagnosis of CS was studied and ruled out. Pulse i.v. methylprednisolone and cyclophosphamide were given and were followed by oral prednisolone and cyclophosphamide. Clinical follow-up showed partial improvement.

Updated assessment of the prevalence, spectrum and case definition of autoimmune disease

Autoimmune diseases are heterogeneous with regard to prevalence, manifestations, and pathogenesis. The classification of autoimmune diseases has varied over time. Here, we have compiled a comprehensive up-to-date list of the autoimmune diseases, and have reviewed published literature to estimate their prevalence. We identified 81 autoimmune diseases. The overall estimated prevalence is 4.5%, with 2.7% for males and 6.4% for females. For specific diseases, prevalence ranges from 1% to <1/10(6). Considering all diseases in the class, the most common mean age-of-onset was 40-50 years. This list of autoimmune diseases has also yielded information about autoantigens. Forty-five autoimmune diseases have been associated with well-defined autoantigens. Of the diseases with known autoantigens, 33.3% had highly repetitive sequences, 35.6% had coiled-coil arrangements and 57.8% were associated with cellular membranes, which means that based on these structural motifs alone, autoantigens do not appear to be a random sample of the human proteome. Finally, we identified 19 autoimmune diseases that phenocopy diseases arising from germline mutations in the corresponding autoantigen. Collectively, our findings lead to a tentative proposal for criteria for assigning autoimmune pathogenesis to a particular disease.

A Case of Cogan's Syndrome With Angina

Cogan's syndrome is a rare systemic inflammatory disease and can be diagnosed on the basis of typical inner ear and ocular involvement with the presence of large vessel vasculitis. We report a case of Cogan's syndrome with stable angina resulting from coronary ostial stenosis caused by aortitis.

Rituximab ameliorated severe hearing loss in Cogan's syndrome: a case report

Background

Rituximab is a monoclonal antibody inducing depletion of B lymphocytes and presently approved for the treatment of non-Hodgkin's lymphoma and rheumatoid arthritis. Here is the first report of the use of this drug in a case of Cogan's syndrome (CS).

Case Presentation

a 25-year-old Italian woman was referred with conjunctival hyperaemia, interstitial keratitis, moderate bilateral sensorineural hearing loss accompanied by tinnitus, dizziness, nausea and vertigo, poorly responsive to oral and topical steroidal therapy. Diagnosis of typical CS was made. The administration of a combined immunosuppressive treatment resolved ocular inflammation, dizziness, nausea, and vertigo but gave little results in controlling progressive hearing loss. A noticeable improvement in hearing function was documented by pure tone audiometry after infusion of Rituximab.

Discussion

in CS, hearing function is often the most difficult parameter to control with therapy. A positive effect of Rituximab on was observed in our case. The drug also allowed to significantly reduce the number of adjuvant immunosuppressive medications.

Cogan syndrome: confocal microscopy assessment of corneal damage

PURPOSE

To perform in vivo assessment of corneal alterations in patients with Cogan syndrome (CS) and to correlate these findings with prior histopathologic descriptions.

METHODS

Four consecutive patients (8 eyes) presenting with typical CS underwent confocal microscopy examination. At the moment of evaluation, ocular inflammation was quiescent in all the patients. The images were studied singularly, and then compared to those obtained from 5 healthy controls. Statistical analysis was performed with Student t test.

RESULTS

All the cases showed multiple brightly reflective deposits in the stroma with moderate reflectivity of the surrounding stromal tissue. The outer corneal layers and the endothelium were spared. In 3/4 of the patients, the nerve fibers of the subepithelial plexus were thin and poorly reflective, with interruptions and lack of the typical branching pattern. No cells different from keratocytes could be detected in either case or control eyes. Corneal vascularization was present in one case. In CS-affected eyes, corneal thickness was 552+/-62 microm on average, and endothelial cell count was 2466+/-288 cells/mm(2). Statistical significance was not reached compared to the control group.

CONCLUSIONS

Confocal microscopy was able to provide detailed images of corneal alterations in CS. This confirmed the interstitial nature of the keratitis and showed an excellent accordance with prior histopathologic findings. The absence of inflammatory cell infiltration may be explained by the prolonged control of ocular inflammation in our patients, which may also have limited stimuli for corneal neovascularization.

Azathioprine-induced warfarin resistance

OBJECTIVE

To describe a case of azathioprine-induced warfarin resistance, present a literature review on warfarin-azathioprine interactions, and provide recommendations on appropriate management of this clinically significant interaction.

CASE SUMMARY

A 29-year-old female with Cogan's syndrome experienced thrombosis of the left internal carotid artery. She was treated with an average weekly warfarin dose of 39 mg (5.5 mg daily) prior to beginning azathioprine therapy. Three weeks following initiation of azathioprine 150 mg daily, the international normalized ratio (INR) decreased from 1.9 (prior to the medication change) to 1.0 without any change in the warfarin dose or other relevant factors. Over several weeks, the patient's warfarin dose was titrated up to 112 mg weekly (16 mg daily) to achieve an INR of 2.5 (a 188%, or 2.9-fold dose increase). Because of elevated liver enzyme levels, the azathioprine dosage was decreased to 100 mg daily. Within 2 weeks following that decrease, warfarin requirements decreased to 105 mg weekly (15 mg daily).

DISCUSSION

Azathioprine was the probable causative agent of warfarin resistance according to the Naranjo probability scale, and a possible causative agent according to the Drug Interaction Probability Scale. A literature search (PubMed, 1966-December 2007) revealed 8 case reports of this drug interaction and 2 cases involving a similar effect with 6-mercaptopurine, the active metabolite of azathioprine. The exact mechanism of the interaction remains unknown. Previously published case reports point to a rapid onset and offset of the warfarin-azathioprine interaction and a dose-dependent increase of at least 2.5-fold in warfarin dose requirement with the initiation of azathioprine 75-200 mg daily.

CONCLUSIONS

This case report and several others point toward azathioprine as a clinically significant inducer of warfarin resistance. Providers should anticipate the need for higher warfarin doses, warfarin dose adjustment, and close INR monitoring in patients receiving azathioprine or its active metabolite, 6-mercaptopurine.