What initial investigations should be considered for a patient presenting with acute vertigo suspected to be due to vestibular neuronitis?

For a patient presenting with acute vertigo suspected to be due to vestibular neuronitis, the initial investigations should focus on clinical assessment rather than extensive imaging or laboratory tests.

Key initial investigations include:

• Performing the HINTS test (Head-Impulse, Nystagmus, Test of Skew) if a healthcare professional trained in this test is available. A negative HINTS test makes a diagnosis of stroke very unlikely, helping to differentiate vestibular neuronitis from central causes such as stroke.
• Assessing for benign paroxysmal positional vertigo (BPPV) using the Hallpike manoeuvre if trained personnel are available, to exclude this common cause of vertigo.
• Checking for focal neurological deficits and other signs that might suggest a central cause requiring urgent referral and neuroimaging.

Routine blood tests or imaging are not indicated initially unless clinical features suggest alternative diagnoses such as stroke or other neurological conditions.

Immediate referral for neuroimaging is warranted if the HINTS test indicates stroke (normal head impulse test, direction-changing nystagmus, or skew deviation) or if there are focal neurological deficits.

In summary, the initial approach relies on detailed clinical examination including the HINTS test and positional testing, with urgent referral and imaging reserved for cases with signs suggestive of central pathology.

References: ¹