neurologic disorders
Acute Bacterial Meningitis
Atypical presentations in adults
Fever and nuchal rigidity may be absent or mild in immunocompromised or older patients and in patients with alcohol use disorder. Often, in older patients, the only sign is confusion in those who were previously alert or altered responsiveness in those who have dementia. In such patients, as in neonates, the threshold for doing lumbar puncture should be low. Brain imaging (MRI or, less optimally, CT) should be done if focal neurologic deficits are present or increased ICP is suspected. If bacterial meningitis develops after a neurosurgical procedure, symptoms often take days to develop. 