Abstract Title: Under Pressure: Brain Abscess and Meningitis Complicated by Orbital and Ethmoidal Encephaloceles-A Pediatric Case Report

Alisa Liberman, BS1, Timur Raghib, MD2 1Midwestern University Arizona College of Osteopathic Medicine, Glendale, AZ; 2Phoenix Children’s Hospital, Phoenix, Arizona

Background An encephalocele is a herniated sac containing meninges and brain tissue that protrudes out of a skull defect. The majority of primary encephaloceles are congenital. Secondary encephaloceles can arise due to trauma, tumors, surgery, and chronic sinusitis. Literature review of infectious pathology associated with encephaloceles yielded documented cases of different type of encephaloceles associated with meningitis and/or empyema in both adult and pediatric populations. Here we present, to our knowledge, the first documented case of brain abscess and meningitis complicated by concurrent orbital and ethmoidal encephaloceles in the pediatric population.

Case Presentation A 10-year-old male with a history of headaches presented to an emergency department with fever, altered mental status, swelling near his right eye and mid-forehead, vomiting, and worsening headaches. One year prior, the patient suffered unspecified skull fractures after a motor vehicle accident and subsequently developed headaches. One week prior to presentation his headaches increased in intensity and frequency. In the emergency department, CT of the head showed pansinusitis, and lumbar puncture showed a leukocyte count 12694, glucose 7, and protein 307. The patient was started on Vancomycin and Ceftriaxone. He was transferred to another hospital, where repeat CT and MRI showed a right inferior frontal lobe abscess with intraventricular extension, right anterior cranial fossa bony defect with an encephalocele protruding into the right superior orbit and a small component extending into right ethmoid, in addition to pansinusitis. The patient underwent endoscopic sinus surgery, cerebral abscess drainage, and external ventricular drain catheter placement. CSF and brain abscess cultures were positive for Streptococcus Pneumoniae and Staphylococcus Aureus/Staphylococcus Epidermis, respectively. The patient was treated with culture-sensitive antibiotics and transitioned to Ceftriaxone and Metronidazole for an additional six weeks.

Discussion This case describes an uncommon presentation of brain abscess and meningitis complicated by worsening orbital and ethmoidal encephaloceles. In our patient, we propose that the encephaloceles initially developed secondary to the patient’s traumatic skull fractures and expanded due to increased intracranial pressure and mass effect from the frontal brain abscess. From this case we learn that even before obtaining imaging, it may be important for clinicians to keep infectious intracranial pathology complicated by encephaloceles on the differential in a patient with a history of skull trauma presenting with fever, altered mental status, forehead and eye swelling, and worsening headaches. Additionally, while clinicians may be cautious in repeating CT/MRI given the radiation/cost, our case illustrates that it may be necessary to prevent diagnostic delay.