Periorbital cellulitis secondary to ethmoiditis in a 5-week-old child.

Periorbital cellulitis is a condition primarily affecting young children. We present a 5-week-old boy who developed periorbital cellulitis and had a CT scan which identified acute ethmoiditis as the source of the sepsis. His clinical course is outlined, and the relevant literature is discussed. We believe this patient is the youngest case of periorbital cellulitis due to confirmed ethmoiditis reported. This emphasises the possibility of an underlying sinusitis in patients with periorbital cellulitis, even in this very young age group.