OVERVIEW
Cogan syndrome, also known as interstitial keratitis-vertigo-neurodeafness syndrome, was first reported by Mogan and Baum Gartner (1934) and later identified as a separate systemic disorder by Cogan (1945). Its main features are: nonsyphilitic interstitial keratitis; vestibular neurologic symptoms such as vertigo; severe bilateral neurologic deafness; and manifestations of systemic vasculitis, such as congestive heart failure and gastrointestinal bleeding. The age of onset is from 5 to 64 years old, with 25 to 29 years old being the most common, and there is no gender difference.
Etiology
Vaccination, upper respiratory tract infection, poisoning, tuberculosis, drug allergy and so on have been proposed. At present, it is believed that the disease is a lesion of the vascular system (polyarteritis, occlusive vasculitis, lesions of the cardiovascular system, etc.), and in combination with renal disease, it belongs to the category of rheumatism.
Symptoms
The onset of the disease is often rapid, with some patients experiencing respiratory tract infections as a precursor, while others begin with polyarthritis or polyarthralgia as the main symptom. Some patients have unexplained fever with skin rash as the first symptom, and some patients have sudden deafness with eye abnormalities as the early manifestation. Systemic symptoms include malaise, fatigue, poor appetite and insomnia.
1. Eye symptoms
There are eye pain, blurred vision, vision loss, foreign body sensation in the eye, etc.. Examination reveals ciliary body congestion, granular conjunctival infiltration, grayish-yellow speckled distribution, more in the posterior half of the cornea, and clear boundaries between infiltration spots. Late in the course of the disease, neovascularization of the cornea may occur, mostly bilateral. The fundus of the eye is normal, and the cornea can be seen under the slit lamp as a glittering infiltration of cholecalciferol-like crystals.
2. 8th pair of neurologic symptoms
After several weeks to months of ocular symptoms, cochlear symptoms may appear, such as tinnitus, hearing loss, hard of hearing, etc., all of which are bilateral vestibular nerve symptoms, and vertigo, nausea, vomiting and uneasiness can be seen, and rotational vertigo can be seen in the early stage.
3. Circulatory system symptoms
Aortic valve insufficiency can be found in about 1/10 patients, and there may be no obvious symptoms in the early stage, and only obvious diastolic murmur can be heard in the aortic valve area during physical examination. With the development of the disease, heart failure symptoms may appear, manifested as palpitations, shortness of breath, lower limb edema.
4. Digestive system symptoms
Some patients may have abdominal discomfort, and in severe cases, gastric and colonic ulcers may appear. Peptic ulcers are caused by mucosal vasculitis, which can sometimes cause upper or lower gastrointestinal bleeding, and individual patients may have diarrhea of unknown cause.
5. Complications
About 1/4 of the patients have joint muscle involvement, which manifests as muscle pain arthritis or arthralgia. About 1/10 patients have hypertension, which may be caused by renal artery involvement. Some patients may present with generalized lymph node enlargement and splenomegaly. Individuals may develop cerebral artery occlusion, which manifests as varying degrees of hemiparesis, headache, speech and movement disorders, and cerebral nerve palsy. Peripheral nerve injury manifests as asymmetric peripheral neuritis.
Examination
1. Laboratory examination
(1) Blood count and sedimentation Most patients have mild to moderate leukocytosis, about 1/3 of patients have eosinophilia, almost all patients have rapid sedimentation, and some patients have increased reticulocytes and platelets.
(2) Immunological examination: A few patients are positive for rheumatoid factor and lupus cells, while immunoglobulin and cellular immunity tests are mostly normal.
2. Other auxiliary examinations
X-ray chest radiograph can see left heart enlargement, whole heart enlargement, and sometimes heart failure changes. Electrocardiogram can find left heart hypertrophy, arrhythmia, and a few patients may have electromyographic abnormalities. Gastroscopy or sigmoidoscopy may reveal ulcerative changes.
Diagnosis
Diagnosis is not difficult based on the presence of specific ocular symptoms followed by the 8th pair of cerebral neurologic symptoms.
Differential diagnosis
1. This disease needs to be differentiated from systemic lupus erythematosus, which has characteristic skin lesions and is positive for antinuclear antibodies and specific antibodies, which makes it easier to differentiate.
2. Rheumatoid arthritis can be easily confused with this disease when there are ocular symptoms and neurological dysfunction in the brain. However, rheumatoid arthritis has more severe joint symptoms and deformities, and the tests for rheumatoid factor and RA-specific antibodies are positive, so it is not difficult to differentiate between the two.
Treatment
Oral or injectable glucocorticosteroids can control the eye symptoms and systemic symptoms, but it is difficult to work on the 8th pair of cerebral nerve symptoms. Prednisone may be used. Recently, cervical sympathectomy has been reported to relieve symptoms of the eighth nerve pair. When there is aortic valve insufficiency and no obvious heart failure, aortic valve replacement can achieve better results and delay the onset of heart failure. Once heart failure or gastrointestinal bleeding occurs, symptomatic treatment should be given, respectively.
Prognosis
The course of the disease varies according to the manner in which the clinical symptoms are manifested. Some patients die within a few months after the onset of the disease, while others may survive for more than 10 years, with an average survival time of 5 to 7 years.
Prevention
1. Prevent possible triggers, the living room should not be too cold and damp, and the temperature should be suitable.
2. Prevent infection, strengthen physical exercise, enhance physical fitness, improve autoimmune function, and live a regular life.