Cogan's syndrome is a disease that causes inflammation of the organ of vision and dysfunction of the organ of hearing. Inflammation in the eyes can be treated. Unfortunately, the involvement of the ear disease quickly leads to irreversible deafness in most cases. What are the causes and symptoms of Cogan syndrome? How is the treatment going?
Cogan's syndromeis an autoimmune disease in which the immune system reacts abnormally to the autoantigens of the eye and inner ear. The consequence of this process is inflammation of various eye structures (most often the cornea) and hearing dysfunction, which usually leads to deafness.
The incidence of Cogan syndrome is unknown. It is only known that it is diagnosed very rarely. In addition, it tends to occur in children and young adults.
Cogan syndrome - causes
Cogan's syndrome is considered to be an autoimmune disease, in which the cells of the immune system attack the body - in this case the structures of the eye and inner ear. However, it is not known what is causing this process.
The evidence of its autoimmune background is, among others, the fact that in the blood of many patients the presence of antibodies to various autoantigens has been detected. In addition, the symptoms of the disease are similar to those of autoimmune deafness, and the disease itself often coexists with polyarteritis nodosa (which is also an autoimmune disease).
Some people believe that a previous infection with one of the common germs may be the trigger for an abnormal reaction of the immune system. All because about 40 percent. several weeks before the appearance of the first symptoms of Cogan's syndrome, there were infections.
Cogan's syndrome - symptoms
1. Typical character
Cogan's syndrome is most often manifested by interstitial keratitis, such as redness of the eye, photosensitivity, lacrimation, pain in the eyeball and a temporary decrease in visual acuity. Additionally, conjunctivitis, subconjunctival haemorrhage or iritis may occur.
U 40-60 percent over time, patients develop complete hearing loss.
In addition, symptoms appear in the course of the diseaseresembling Meniere's syndrome (sudden, severe dizziness, tinnitus, nausea and vomiting, impaired motor coordination, falls) with progressive hearing loss (usually bilateral), which very quickly, within 1-3 months, leads to deafness. It should be noted that symptoms resembling Meniere's syndrome last until the hearing loss occurs, and then partially or completely disappear.
The time between the onset of eye and ear symptoms can be up to 2 years.
2. Atypical character
In addition to the typical form of Cogan's syndrome described above, there is also the atypical form, in the course of which there are visual symptoms other than those that occur in the typical form (e.g. choroiditis). In turn, the visual symptoms are accompanied by - similarly to the typical Cogan syndrome - symptoms resembling Meniere's syndrome with progressive hearing loss.
It may also be the other way around, i.e. typical visual symptoms may accompany other ear symptoms than those associated with Meniere's syndrome.
In atypical Cogan syndrome, the time between the onset of ear and eye symptoms is greater than 2 years.
3. Other symptoms
Besides, both in the typical and atypical form, in 20-50 percent patients, especially in the initial stage of the disease, may develop non-specific systemic symptoms, such as fever, joint pain, headache, cough, dyspnoea or hemoptysis.
Cardiac complications are the most common cause of death in patients with Cogan syndrome.
In addition, about 10 percent of Patients suffer from generalized vasculitis that can lead to inflammation of the coronary vessels of the heart, brain, or subarachnoid haemorrhage, which can be fatal. The disease may spread to other systems, e.g. digestive (usually manifested by diarrhea, rectal or melaena bleeding, or abdominal pain), nervous (headache, paresis or paralysis, aphasia, seizures), skin and mucous membranes ( erythematous or urticarial rashes are characteristic), and even attack the osteoarticular system.
Cogan syndrome - diagnosis
If Cogan's syndrome is suspected, blood tests are performed, but the final diagnosis is made on the basis of the above-mentioned symptoms.
It is worth knowing that similar symptoms can be caused by numerous autoimmune diseases, such as Vogt-Koyanagi-Harada syndrome, systemic vasculitis (e.g. polyarteritis nodosa, Susac syndrome, Wegener's granulomatosis, Horton's disease, Behcet's disease), andsarcoidosis, polychondritis, rheumatoid arthritis, Sjogren's syndrome and systemic lupus erythematosus. Therefore, the doctor should rule out these diseases.
Cogan's syndrome - treatment
The patient is given immunosuppressive drugs, that is "silencing" the reactions of the immune system. The most common are glucocorticosteroids. If the patient does not respond to them, other immunosuppressants are given (e.g. cyclophosphamide, azathioprine). Immunoglobulin preparations will also work for Cogan's syndrome. In addition, plasma exchange transfusion can be performed.
In the treatment of patients for whom glucocorticosteroids and other immunosuppressive drugs are ineffective, high hopes are associated with biological drugs (TNF blockers). It is believed that their use in the initial stage of the disease may inhibit the destruction of the organ of hearing and balance, and thus - prevent complete deafness.
In the case of irreversible deafness, the use of cochlear implants may be helpful.