Cogan syndrome

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Cogan syndrome is a rare vasculitis of children and young adults which primarily characterised by ^1,4,6:

inflammatory eye disease (ocular keratitis, uveitis, scleritis, optic neuritis) ⁶
audiovestibular symptoms (similar to Meniere disease) ⁶

However, it can potentially affect a multitude of other organs (classically aortitis) ⁴.

Cogan syndrome (CS) is the combination of episodic attacks of interstitial keratitis and audiovestibular disturbance due to autoimmune reaction to the eyes and the audiovestibular structures.

PathologyEpidemiology

CS is a rare disorder that can occur in people of any age and race, and it most frequently starts in young adults in their late 20’s or early 30’s.

~~Aetiology~~

Clinical presentation

Inflammation of the eyes
Audiovestibular dysfunction
- nausea
- vomiting
- tinnitus
- vertigo
- hearing loss
Later on:
- fatigue
- headaches
- joint pains
- rashes

~~The exact aetiology~~Hearing loss progresses for 1 to 3 months and deafness occurs in about 60% of patients.

Auditory symptoms can precede or follow eye disease, usually within a short period of time.

Atypical Cogan syndrome (audiovestibular dysfunction with other types of inflammatory eye disease) is ~~not well known although an autoimmune aetiology~~associated with vasculitis in 20% of cases and has ~~been postulated~~a less favourable prognosis than typical Cogan syndrome.

TreatmentPathophysiology

Autoimmune reaction to the eyes and ~~prognosis~~

~~The onset of~~

the ~~disease is usually rapid with ocular findings preceding tinnitus and vertigo. If untreated the majority of patients will become deaf and 5% will be blind.~~ ~~~~Aortitis~~ ~~and aortic insufficiency develop in 10-15% of patients. Prognosis is good in patients without symptoms of aortitis and early steroid treatment may prevent deafness~~ ⁶~~audiovestibular structures possibly triggered by upper respiratory infection.

~~History and etymology~~

~~It was initially described by~~ ~~David Glendenning Cogan,~~ ~~American ophthalmologist (1908-1993) in 1945~~ ⁵.

Histopathology

Vestibule-cochlear structures demonstrate endolymphatic hydrops with perilymphatic compartments filled with loose fibrous tissue.

Radiographic features

MRI

post-contrast T1-weighted images of the middle ears show enhancement of the vestibule-cochlear, ampulla and semicercular canals
features of small and large vessel vasculitis

Differential diagnosis

lyme disease
syphilis
chlamydia
whipple’s disease

other systemic inflammatory diseases

Crohn’s, Behcet’s, Relapsing polychondritis, rheumatoid arthritis, sarcoidosis, Sjogren’s syndrome, systemic lupus, vasculitis, and Vogt-Koyanagi-Harada syndrome

Treatment

glucocorticoid therapy
immunosuppressive therapy
anti-tumour necrosis factor (TNF) therapy

Prognosis

the course of the disease varies significantly from patient to patient.
in some patients there is an initial flare, which may last several weeks to months.
following this there may be a slowly progressive course in some patients while others have a course of complete remission with intermittent episodes of disease activity.
life-threatening aortic insufficiency develops in 10% of reported cases.
blindness occurs in less than five per cent of patients.
deafness is a frequent and debilitating outcome occurring in up to 54% of patients.

Practical points

prompt recognition and exclusion of other diseases with similar presentation.
prompt treatment with glucocorticoids and secondary line immunosuppressive therapy if not responding.
awareness of development of vasculitis and particularly aortitis with associated complications

History and etymology

It was initially described by David Glendenning Cogan, American ophthalmologist (1908-1993) in 1945 ⁵.

-</ul><p>However, it can potentially affect a multitude of other organs (classically <a href="/articles/aortitis">aortitis</a>) <sup>4</sup>.</p><h4>Pathology</h4><h5>Aetiology</h5><p>The exact aetiology is not well known although an autoimmune aetiology has been postulated. </p><h4>Treatment and prognosis</h4><p>The onset of the disease is usually rapid with ocular findings preceding tinnitus and vertigo. If untreated the majority of patients will become deaf and 5% will be blind. <a href="/articles/aortitis">Aortitis</a> and aortic insufficiency develop in 10-15% of patients. Prognosis is good in patients without symptoms of aortitis and early steroid treatment may prevent deafness <sup>6</sup>.</p><h4>History and etymology</h4><p>It was initially described by <strong>David Glendenning Cogan,</strong> American ophthalmologist (1908-1993) in 1945 <sup>5</sup>.</p>
+</ul><p>However, it can potentially affect a multitude of other organs (classically <a href="/articles/aortitis">aortitis</a>) <sup>4</sup>.</p><p><strong>Cogan syndrome (CS)</strong> is the combination of episodic attacks of interstitial keratitis and audiovestibular disturbance due to autoimmune reaction to the eyes and the audiovestibular structures.</p><h4>
+<strong> </strong>Epidemiology</h4><p>CS is a rare disorder that can occur in people of any age and race, and it most frequently starts in young adults in their late 20’s or early 30’s.</p><h4>
+<strong> </strong>Clinical presentation</h4><ul>
+<li>Inflammation of the eyes</li>
+<li>Audiovestibular dysfunction<ul>
+<li>nausea</li>
+<li>vomiting</li>
+<li>tinnitus</li>
+<li>vertigo</li>
+<li>hearing loss</li>
+</ul>
+</li>
+<li>Later on:<ul>
+<li>fatigue</li>
+<li>headaches</li>
+<li>joint pains</li>
+<li>rashes</li>
+</ul>
+</li>
+</ul><p>Hearing loss progresses for 1 to 3 months and deafness occurs in about 60% of patients.</p><p>Auditory symptoms can precede or follow eye disease, usually within a short period of time.</p><p><strong>Atypical Cogan syndrome</strong> (audiovestibular dysfunction with other types of inflammatory eye disease) is associated with vasculitis in 20% of cases and has a less favourable prognosis than typical Cogan syndrome.</p><h4>Pathophysiology</h4><p>Autoimmune reaction to the eyes and the audiovestibular structures possibly triggered by upper respiratory infection.</p><h4>Histopathology</h4><p>Vestibule-cochlear structures demonstrate endolymphatic hydrops with perilymphatic compartments filled with loose fibrous tissue.</p><h4>Radiographic features</h4><h5>MRI</h5><ul>
+<li>post-contrast T1-weighted images of the middle ears show enhancement of the vestibule-cochlear, ampulla and semicercular canals</li>
+<li>features of small and large vessel vasculitis</li>
+</ul><h4>Differential diagnosis</h4><ul>
+<li>lyme disease</li>
+<li>syphilis</li>
+<li>chlamydia</li>
+<li>whipple’s disease</li>
+</ul><p> other systemic inflammatory diseases</p><p>Crohn’s, Behcet’s, Relapsing polychondritis, rheumatoid arthritis, sarcoidosis, Sjogren’s syndrome, systemic lupus, vasculitis, and Vogt-Koyanagi-Harada syndrome</p><h4>Treatment</h4><ul>
+<li>glucocorticoid therapy</li>
+<li>immunosuppressive therapy</li>
+<li>anti-tumour necrosis factor (TNF) therapy</li>
+</ul><h4>
+<strong> </strong>Prognosis</h4><ul>
+<li>the course of the disease varies significantly from patient to patient.</li>
+<li>in some patients there is an initial flare, which may last several weeks to months.</li>
+<li>following this there may be a slowly progressive course in some patients while others have a course of complete remission with intermittent episodes of disease activity.</li>
+<li>life-threatening aortic insufficiency develops in 10% of reported cases.</li>
+<li>blindness occurs in less than five per cent of patients.</li>
+<li>deafness is a frequent and debilitating outcome occurring in up to 54% of patients.</li>
+</ul><h4>Practical points</h4><ul>
+<li>prompt recognition and exclusion of other diseases with similar presentation.</li>
+<li>prompt treatment with glucocorticoids and secondary line immunosuppressive therapy if not responding.</li>
+<li>awareness of development of vasculitis and particularly aortitis with associated complications</li>
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+ <w:LsdException Locked="false" Priority="32" SemiHidden="false"
+ UnhideWhenUsed="false" QFormat="true" Name="Intense Reference"/>
+ <w:LsdException Locked="false" Priority="33" SemiHidden="false"
+ UnhideWhenUsed="false" QFormat="true" Name="Book Title"/>
+ <w:LsdException Locked="false" Priority="37" Name="Bibliography"/>
+ <w:LsdException Locked="false" Priority="39" QFormat="true" Name="TOC Heading"/>
+ </w:LatentStyles>
+</xml><![endif]--><!--[if gte mso 10]>
+<style>
+ /* Style Definitions */
+ table.MsoNormalTable
+ {mso-style-name:"Table Normal";
+ mso-tstyle-rowband-size:0;
+ mso-tstyle-colband-size:0;
+ mso-style-noshow:yes;
+ mso-style-priority:99;
+ mso-style-parent:"";
+ mso-padding-alt:0cm 5.4pt 0cm 5.4pt;
+ mso-para-margin-top:0cm;
+ mso-para-margin-right:0cm;
+ mso-para-margin-bottom:10.0pt;
+ mso-para-margin-left:0cm;
+ line-height:115%;
+ mso-pagination:widow-orphan;
+ font-size:12.0pt;
+ mso-bidi-font-size:11.0pt;
+ font-family:"Garamond","serif";
+ mso-fareast-language:EN-US;}
+</style>
+<![endif]--></p><h4>History and etymology</h4><p>It was initially described by <strong>David Glendenning Cogan,</strong> American ophthalmologist (1908-1993) in 1945 <sup>5</sup>.</p>