Atypical skull base osteomyelitis in the intensive care unit: A case report

Abstract

Base of skull osteomyelitis is commonly seen as a complication of malignant otitis externa, involving the temporal bone. It initially presents with aural symptoms such as ear ache and discharge and cranial nerve palsies. We report an atypical presentation of skull base osteomyelitis that did not show signs of otitis externa. The patient presented with severe headache, drowsiness and signs of bulbar weakness including pooling of oropharyngeal secretions. Computerized Tomography (CT) and Magnetic Resonance Imaging (MRI) studies showed a bony erosion of the left side of base of skull involving the sphenoid bone and surrounding foramina, left sided coalescent mastoiditis and inflammation of the left parapharyngeal space. There was also inflammation of the tissues encasing the internal carotid artery and jugular veins and thrombosis of left jugular vein. These imaging findings along with cranial nerve palsies were suggestive of malignancy. However, tissue biopsy was negative for malignancy. The growth of Pseudomonas aeruginosa in the biopsy material as well as nasopharyngeal and blood cultures along with elevated Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP) levels led to a diagnosis of base of skull osteomyelitis. Hence diagnosis in such cases requires that biopsy material be sent for microbiological analysis, in addition to histology.