meningosepticum

Meningosepticum is an older designation that has been used to refer to the bacterium now classified as Elizabethkingia meningoseptica, previously known as Chryseobacterium meningosepticum. It is a Gram-negative, non-fermenting, non-motile rod that inhabits environmental sources such as soil and freshwater and can colonize hospital water systems and equipment.

Clinical significance centers on infections caused by Elizabethkingia meningoseptica, including meningitis and septicemia (meningosepsis). Neonates in intensive care units are particularly at risk, but immunocompromised adults and patients with invasive devices can also be affected. In neonates, disease may present with fever, lethargy, poor feeding, seizures, and signs of meningitis or sepsis. Infections can be severe and historically have been associated with high mortality, especially in vulnerable populations.

Diagnosis relies on isolation of the organism from sterile sites such as blood or cerebrospinal fluid. Laboratory identification is supported by culture and species-level testing, with newer methods such as MALDI-TOF mass spectrometry and molecular assays improving accuracy. Because Elizabethkingia meningoseptica exhibits intrinsic resistance to many antibiotics, antimicrobial susceptibility testing is essential to guide therapy.

Treatment is individualized and often challenging due to broad antibiotic resistance. Commonly active options reported in isolates include fluoroquinolones (e.g., ciprofloxacin or levofloxacin), trimethoprim-sulfamethoxazole, rifampin, and, in some cases, minocycline or piperacillin-tazobactam, depending on susceptibility. Monotherapy is not unusual, but combination therapy may be considered for severe infections.

Prevention focuses on strict infection-control practices and monitoring of hospital water sources and contaminated devices to reduce nosocomial transmission.