Abstract
Introduction: Brain abscess is an unusual complication that may occur in uncontrolled diabetes. A solitary thalamic abscess is an uncommon type of brain abscess. We report a case of Type 2 diabetes that presented with a solitary thalamic abscess and discuss the diagnostic protocol and management. Case presentation: A 56-year-old, Caucasian, British male with no medical or travel history presented with 5day symptoms of meningeal irritation. Body mass index 30.6kg/m2. CT demonstrated a solitary midline lesion with neoplasia as a differential diagnosis. It was biopsied and cultures grew Streptococcus milleri. He was treated by stereotactic puncture and then external drainage and targeted intrathecal and systemic antibiotic therapy. He was HIV negative but HbA1c was 10.7%. Dental examination revealed a small molar abscess. The time to radiological resolution of the thalamic abscess was 2 months. Diabetes improved with 2months of (tapered-dose) insulin and maintained on metformin with HbA1c 6.9%. He was left with no neurological disability. Discussion: Brain abscess classically presents with fever, headache and neurological deficit. It is treated by antimicrobial therapy and surgical drainage. Haematogenous spread is usually to the middle cerebral artery territory, although infrequently to deeper tissues, such as the thalamus. Streptococci are the cause of most brain abscesses and S. milleri (present in the oral cavity and upper respiratory tract) is the most common pathogen. Predisposing factors for S. milleri infections include mucosal infection (periodontal diseases and paranasal sinusitis), pneumonia, alcohol abuse and uncontrolled diabetes. This case highlights the unusual way diabetes may present and the importance of periodontal care in diabetes.