Cryptogenic left parieto-occipital brain abscess in a previously healthy 24 year old woman

Abstract

Background: Brain abscesses are a rare form of neurologic infection that can be attributed to a primary source of infection 60–70% of the time. Cases that cannot be attributed to a primary source of infection are rare and are deemed cryptogenic. Brain abscesses are more commonly seen in the frontal & temporal lobes contiguous with primary infections. Parietal and occipital lobe abscesses are uncommon locations. Diagnosis is typically made through advanced imaging, CT scan or MRI. Treatment involves neurosurgical drainage and intravenous antibiotics. Prognosis of an abscess depends on myriad factors but residual neurologic deficits or development of epilepsy can be seen. Death can occur if an abscess ruptures or the abscess is complicated by the patient's underlying chronic health problems. Case study: A 24 year old, previously healthy and immunocompetent woman presented to the emergency department with complaints of new headache and suspected seizure at home. She subsequently had two witnessed seizures in the ER and underwent CT of the head which showed a parieto-occipital mass, suspected to be a neoplasm. MRI findings were consistent with CT, abscess was less likely. She underwent biopsy which revealed a brain abscess with Streptococcus intermedius. No primary source of infection or risk factor other than marijuana use was identified. During regular screening her abscess increased in size and she subsequently underwent further drainage and intravenous antibiotic therapy. Conclusion: Advanced imaging has helped to diagnose brain abscesses in patients who present with new neurologic complaints. While brain abscesses are rare they should remain on a clinician's differential in a patient with new neurologic symptoms, particularly if they have risk of developing an abscess such as immunodeficiency, recent neurologic procedure, or cranial trauma. Clinicians must be aware that an abscess can occur without risk factors being present such as this case. Keywords: Brain abscess, Cryptogenic abscess, Streptococcus intermedius, Occipital lobe abscess, Parietal lobe abscess