Background/Objectives: Neisseria meningitidis is a human-specific pathogen capable of causing life-threatening illnesses. Occasionally, it is recovered from unusual sites, other than the bloodstream or the central nervous system. Herein, we describe two rare manifestations due to N. meningitidis within a year (2024) in Greece. Methods: Atypical infection due to N. meningitidis was diagnosed in two different patients: Case-1 presented with an inflammatory swelling in the mid-line of the neck, and Case-2 presented with swelling of the left knee. Both patients had high fever and no neurological signs at admission; Case-2 progressed to meningoencephalitis. Phenotypic and genotypic identifications were carried out in both cases. Results: Case-1 and Case-2 isolates were identified as follows: MenX: 18, 25-44, F5-5, ST-823; 198cc and MenB: 7-1, 1, F3-3, ST-7460; 32cc for PorA, FetA and MLST, respectively. MenX was identified for the first time in Greece and finetyping revealed rare genotypic characteristics. Both isolates were susceptible to cefotaxime, ceftriaxone and rifampicin, while Case-2 isolate expressed reduced susceptibility to penicillin and resistance to ciprofloxacin. Both patients recovered fully. Conclusions: Although uncommon, N. meningitidis may be isolated from atypical sites and specimens. Clinicians and microbiologists should remain aware that meningococcus is a potential cause of infections beyond meningitis and septicaemia.

Neurosurgical devices provide clinical benefits that are undermined by the incidence of device-related infections. This study examined the microbiological and clinical characteristics of central nervous system (CNS) infections associated with cerebrospinal fluid (CSF) shunts and drains in neurosurgery patients during August 2022–July 2024. Upon suspicion of CNS infection, CSF samples were submitted for cytology, biochemical analysis, and culture. Identification and susceptibility testing were performed by VITEK-2 and VITEK-MS PRIME (bioMérieux); susceptibility to colistin was determined by broth microdilution (Bruker). The results were interpreted according to EUCAST guidelines. An infection definition was based on IDSA’s guidelines, and the outcome was considered positive upon successful therapeutic intervention. Out of 825 CSFs, 178 showed microbial growth in culture; they corresponded to 102 patients. Neurosurgical devices were implanted in 68 patients and, among them, 29 presented with a CNS infection. The infections attributed to drains and shunts were 72% versus 28%, respectively. Polymicrobial or consecutive infections occurred in 6/29 patients. Overall, 40 pathogens were isolated. The predominant causative agents were Acinetobacter baumannii (40%), Klebsiella pneumoniae (12.5%), coagulase-negative-Staphylococci (12.5%), and Pseudomonas aeruginosa (10%). Neurosurgical devices are easily contaminated and may cause CNS infections, regardless of the device type. The infections’ outcome is multifactorial; timely diagnosis and intervention are of utmost importance.