Differential Diagnosis for Truncal Ataxia and Ataxic Gait in a Child
Single Most Likely Diagnosis
- Acute Cerebellitis: This condition is an inflammation of the cerebellum and is a common cause of truncal ataxia and ataxic gait in children. It can be post-infectious or idiopathic, and the normal labs and CT head do not rule out this diagnosis, as cerebellitis can be diagnosed clinically and with MRI.
Other Likely Diagnoses
- Cerebellar Astrocytoma: A type of brain tumor that can cause ataxia due to its location in the cerebellum. Although the CT head is normal, MRI would be more sensitive for detecting this tumor.
- Posterior Fossa Arachnoid Cyst: A congenital condition that can cause cerebellar dysfunction and ataxia due to compression or distortion of the cerebellum.
- Inherited Ataxias: Such as Friedreich's ataxia or ataxia-telangiectasia, which can present with progressive ataxia, but may have a more gradual onset.
Do Not Miss Diagnoses
- Brainstem Stroke: Although rare in children, a stroke in the brainstem can cause ataxia and is a medical emergency. Normal labs and CT head do not rule out this diagnosis, and an MRI or MRA would be necessary to evaluate for this condition.
- Chiari Malformation: A structural defect in the cerebellum that can cause ataxia and other neurological symptoms. It is essential to evaluate for this condition with an MRI.
- Intracranial Hypotension: Can cause ataxia due to sagging of the brain, and is a diagnosis that requires a high index of suspicion and further evaluation with MRI or lumbar puncture.
Rare Diagnoses
- Ataxia with Vitamin E Deficiency (AVED): A rare inherited disorder that causes progressive ataxia due to vitamin E deficiency.
- Abetalipoproteinemia: A rare genetic disorder that affects fat absorption and can cause ataxia due to vitamin E deficiency.
- Cerebrotendinous Xanthomatosis: A rare genetic disorder that affects cholesterol metabolism and can cause ataxia and other neurological symptoms.