IntroductionThe incidence of Acinetobacter baumannii meningitis, which typically occurs after neurosurgery, has increased in recent years. Pediatric Acinetobacter baumannii meningitis due to the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains has important clinical significance. Methodology We retrospectively reviewed the clinical course and outcome of nine cases of meningitis due to Acinetobacter baumannii in children and reviewed the relevant literature. Results Seven patients had a history of neurosurgery, and the average time from the first surgery to cerebrospinal fluid (CSF) culture in these seven patients was 23.71 ± 17.43 days. Of all nine patients, four patients showed MDR isolates, two showed XDR isolates, and one showed pan-drug-resistant (PDR) isolates. Three patients received an intrathecal injection of amikacin. Two patients received intravenous colistin (5 mg/kg), and one received polymyxin B (2 mg/kg). The mean hospitalization duration was 39.44 days. Four patients eventually died: two with MDR Acinetobacter, one with PDR Acinetobacter, and one with susceptible Acinetobacter. Two of them still had positive CSF cultures at death. Conclusion Acinetobacter baumannii meningitis is usually associated with neurosurgery and the placement of foreign material, and it usually has a high mortality. Intrathecal or intraventricular polymyxin administration is expected to be an effective choice for meningitis but requires further study.

Haemophilus influenzae (H. influenzae) is a significant pathogen responsible for causing respiratory tract infections and invasive diseases, leading to a considerable disease burden. The Haemophilus influenzae type b (Hib) conjugate vaccine has notably decreased the incidence of severe infections caused by Hib strains, and other non-typable H. influenzae (NTHi) serotypes have emerged as epidemic strains worldwide. As a result, the global epidemic trends and antibiotic resistance characteristics of H. influenzae have been altered. Researches on the virulence factors of H. influenzae, particularly the mechanisms underlying biofilm formation, and the development of anti-biofilm strategies hold significant clinical value. This article provides a summary of the epidemic trends, typing methods, virulence factors, biofilm formation mechanisms, and prevention strategies of H. influenzae. The increasing prevalence of NTHi strains and antibiotic resistance among H. influenzae, especially the high β-lactamase positivity and the emergence of BLNAR strains have increased clinical difficulties. Understanding its virulence factors, especially the formation mechanism of biofilm, and formulating effective anti-biofilm strategies may help to reduce the clinical impact. Therefore, future research efforts should focus on developing new approaches to prevent and control H. influenzae infections.