821: FULMINANT AND FATAL SEPTIC CAVERNOUS SINUS THROMBOSIS IN BACTERIAL AND VIRAL COINFECTION

Introduction: Mortality has dramatically reduced for SCVT in the antibiotic era. We report a rapidly progressive case of SCVT due to community acquired methicillin resistant Staphylococcus aureus (CA-MRSA) and viral coinfection despite antibiotic therapy in a pediatric patient. Description: A previously healthy 19-month-old girl presented with fever and vomiting for 2 days, and rhinorrhea and cough for 10 days. Her clinical examination, laboratory studies and chest x-ray were unremarkable except for fever of 39.7C and respiratory viral panel PCR revealing Parainfluenza 3 virus. She developed two episodes of left eye deviation concerning for focal seizures that were treated with lorazepam and levetiracetam. Lumbar puncture was attempted, brain CT scan and EEG were unremarkable, and vancomycin and ceftriaxone were commenced. She developed worsening lethargy, left eye proptosis and ptosis, dilated and unresponsive left pupil, and right arm extension within 6 hours of admission. Emergent brain CT scan revealed bilateral infarction in the left middle, left anterior, and right anterior cerebral arterial territories with left preseptal cellulitis and sinusitis. Cerebral protection therapies were initiated, and she was transferred to a quaternary care institution where brain CT scan and CT angiography on admission revealed heterogenous flow and narrowing of bilateral internal carotid arteries, cavernous sinus thrombosis and left orbital edema. External ventricular drain placement revealed low intracranial pressure. CSF and blood cultures were positive for MRSA. She developed diabetes insipidus within 2 hours, and her right pupil became dilated and unresponsive at 16 hours. Repeat brain CT scan revealed diffuse cerebral edema with tentorial herniation and she was pronounced dead by neurologic criteria. Whole genome sequencing of MRSA revealed USA300 strain harboring Panton Valentine leukocidin toxin genes. Discussion: CA-MRSA and Parainfluenza coinfection resulted in a fulminant course of SCVT causing internal carotid arteritis, ophthalmoplegia, pituitary ischemia, diffuse cerebral infarctions and meningitis leading to cerebral herniation. It is plausible that viral airway epithelium damage facilitated initiation and exacerbation of CA-MRSA spread in our patient.