Table 3 Suggested initial diagnostic work-up for paediatric patients with suspected Cogan's syndrome

Laboratory:

Inflammatory markers

CBC

Electrolytes, creatinine, liver tests, urinalysis

Infectious work-up

ACE, s-IL2R, Ca in urine

T-spot

ANA, ENA, ANCA

C3, C4, CH50

Mostly elevated

Often anaemia, eosinophilia, increased WBC and PLT

To detect possible multiorgan involvement or alternative diagnosis

To exclude Chlamydia trachomatis, Treponema pallidum, Lyme disease, toxoplasmosis, CMV, EBV, Mycoplasma

To exclude sarcoidosis

To exclude tuberculosis

To exclude systemic lupus erythematodes, ANCA- associated vasculitis

Audiometry

To diagnose and monitor hearing deficit

BERA

To confirm sensorineural hearing deficit especially in children unable to cooperate during audiometry

Vestibular evoked myogenic potentials

Video head impulse testing

Rotary chair testing

Caloric testing

To asses vestibular function

Ophthalmologic investigation including slit lamp

To detect interstitial keratitis, uveitis, papilledema, synechia as long-term consequences of uveitis, secondary glaucoma as a result of corticosteroid therapy and to monitor visual acuity

MRI brain and inner ear with gadolinium

To exclude cerebellopontine tumours or stroke

Enhancement of cochlea and labyrinth with gadolinium as signs of inflammation may support the diagnosis

Pre-operative assessment before CI (may need to be supplemented by HRCT)

Echocardiography

To detect and monitor aortic root dilatation and aortic regurgitation

Cerebrospinal fluid in case of neurological symptoms

To exclude meningoencephalitis of infectious or other etiology