Infratentorial subdural empyemas mimicking pyogenic meningitis
A 17-year-old boy presented to our hospital with high spiking fever, chills rigors associated with vomiting and headache for the past 3 days. He also had a history of intermittent purulent right ear discharge since 6 years of age. There were no focal neurological signs or papilledema to suggest raised intracranial tension. A CT scan of the head done by the referring doctor was normal. Lumbar puncture showed increased proteins (210 mg/dL) with normal sugars. Cerebrospinal spinal fluid analysis (CSF) showed 3000 cells, 84% of them being neutrophils. Gram staining was negative for bacteria and CSF cultures were sterile. He was treated as pyogenic meningitis and was started on a combination of Ceftriaxone, Amikacin, and Tinidazole. His fever promptly responded to the antibiotics, but he repeatedly complained of a persistent headache. He was also diagnosed with bilateral atticoantral CSOM with a right-sided cholesteatoma. In view of the persistent headache, a contrast MRI study of the brain was obtained and it revealed a right-sided enhancing subtentorial subdural collection suggestive of a subdural empyema [].\nNeurosurgical consult was sought and the patient was transferred under our care for further management. As the boy was afebrile with no evidence of raised intracranial tension, he was initially managed conservatively with antibiotics. Over the next few days his headache and vomiting subsided, but he kept complaining of repeated episodes of severe neck pain every night at around 3 am.\nA repeat contrast-enhanced computed tomography scan (CECT) done 10 days later using a 64 slice scanner revealed that the collection had greatly increased in size and now measured 4.5 × 2.5 cm and was associated with secondary hydrocephalus []. The boy was taken up for a right retromastoid suboccipital craniectomy and about 15 ml of frank subdural pus was aspirated, and the subdural space gently washed out with antibiotic solution. Pus was sent for culture but later failed to show any bacterial growth.\nPost-operative period, he did well with no recurrence of fever or neck pain. Intravenous antibiotics were continued for the next 10 days. At the time of discharge he was afebrile and neurologically intact with no focal deficits. He was advised to attend the ENT outpatient department period for further management of his middle ear infection.