Staphylococcus aureus meningitis is rarely encountered in clinical practice. It is described as a community-acquired ailment that can occur without any major risk factors, but intrahospital infections, mostly associated with neurosurgical interventions, are much more common. Fever is the main symptom, whereas headaches, vomiting, seizures, nuchal rigidity and altered consciousness are reported in a variable number of cases. Examination of the cerebrospinal fluid and subsequent implementation of microbiological studies is pivotal in order to confirm Staphylococcus aureus as the cause of meningitis.
Bacterial meningitis is a potentially life-threatening condition caused by a myriad of pathogens. Staphylococcus aureus, a gram-positive bacteria that is responsible for many types of diseases, is rarely described in patients with meningitis. However, it may develop as a community-acquired (CA) infection with a primary source outside of the central nervous system -CNS (skin, soft tissues, heart valves, or bacteremia)  , or as a nosocomial infection, with head trauma and associated neurosurgical procedures (craniotomy, use of ventricular catheters, intrathecal administration of drugs or infusions, cerebrospinal fluid leakage, etc.) serving as risk factors for the introduction of pathogens in the CNS   . In a small number of cases, additional comorbidities, eg. diabetes mellitus, intravenous drug use, and severe alcohol abuse are noticed, possibly contributing to the pathogenesis   . Several studies have confirmed that fever is almost universally present in people suffering from Staphylococcus aureus meningitis (SAM), whereas symptoms related to meningeal irritation, such as headaches and nuchal rigidity are not always reported   . Furthermore, altered consciousness (ranging from mild alterations in the mental state to coma) and seizures, as well as other focal neurological deficits, vomiting, and a rash are observed in patients who developed SAM   .
Mortality rates of Staphylococcus aureus meningitis are about 35% according to different case series  , suggesting that an early diagnosis and proper treatment can be life-saving. For this reason, the role of the physician in obtaining a detailed history and conducting a thorough physical examination is crucial. During collection of anamnestic data, recent trauma to the head and neck area or neurosurgical procedures can point to S. aureus as the underlying etiology. The presumptive diagnosis of meningitis can be made after conducting a proper neurological examination and the evaluation of meningeal signs, but they may be positive in only 29% cases , which is why laboratory studies need to be employed. Examination of the cerebrospinal fluid (CSF) is a vital step that aids in discriminating the etiologic factors of CNS diseases . In bacterial meningitis, typical findings are pleocytosis (with a predominance of polymorphonuclear leukocytes), elevated protein levels, and very low concentrations of sugar (hypoglycorrhachia) . Serum inflammatory parameters: C-reactive protein (CRP) and calcitonin are important markers of an ongoing inflammatory process caused by bacteria, but microbiological exams must be used in order to identify the exact pathogen . The culture of CSF, Gram-staining (useful for culture-negative meningitis as it provides fast results), latex agglutination tests, and polymerase chain reaction (PCR), which detects bacterial DNA in the CSF, are constituents of the microbiological workup  . Blood cultures may also provide important information in the presence of a systemic infection .