Comparison of clinical characteristics of typical versus atypical SBO

	Typical SBO	Atypical SBO
Age	Elderly	Middle-aged
Predisposing factors	DM more common than immunocompromised	DM, immunocompromised
Clinical features	Otorrhea, otalgia (severe, with pain out of proportion to the physical findings), hearing loss	Headache, atypical facial pain, cranial neuropathies, sinonasal symptoms in 25%
Cranial nerve involvement	VII most common	VI, IX, and X more common than VII
Pathogen	P aeruginosa in most cases; fungal more common in immunosuppressed patients without diabetes	S aureus slightly more common than P aeruginosa and fungal
Primary epicenter of disease process	EAC, petrous apex, and clivus	Central skull base, sphenoid bone, or clivus with or without evidence of regional infection of the sinuses, deep face, or oral cavity

Note:—DM indicates diabetes mellitus.