Chiari I malformation with significant motor and autonomic dysfunction in an infant.

Quadriparesis and cardiovascular instability are not symptoms commonly associated with Chiari I malformation diagnoses, less so in a 3-month-old toddler. Chiari I malformations have a wide array of symptoms, varying with regard to both the nature of onset and the age of the patient presenting. This variation is illustrated in this report, presenting a novel description of a set of symptoms in a particularly young patient, a case lacking the common insidious nature of Chiari I malformation symptoms. Acute onset of cardiovascular instability, global hypertonia, hyperreflexia, and proximal upper limb weakness in a 3-month-old toddler are discussed. Parallels between the presented case and previous case reports are few, however some key features are distinguishable among similar cases. A successful posterior fossa craniectomy allowed the acutely unwell toddler to become a healthy, fully functional child. We believe this case contributes to elucidating the rare presentations of a curious pathology.