Meningitis Caused by Neisseria meningitides Serogroup B in a Newborn in China

section at 41 weeks’ gestation with a birth weight of 3545g. During pregnancy, his mother was healthy. The natal history was unremarkable. Apgar score was all 10 at 1, 5 and 10 minute. He was breastfed. The neonate was admitted to the hospital due to a one-day history of fever, dispirited, choking, without convulsion, diarrhea or rash. Blood routine: White Blood Cell (WBC) 5.49×109/ L, neutrophilic granulocyte 66.1%, lymphocytes 29.3%, hemoglobin, platelets and C-reactive protein (CRP) were normal. X-ray of the chest was unremarkable. No special findings except the total bilirubin, direct and indirect bilirubin were slightly elevated. No exposure to cold patients.


Introduction
Neonatal bacterial meningitis is a major disease that results in death and significant morbidity worldwide.It is characterized by an infection of the Central Nervous System (CNS) and caused by a limited range of bacteria.Of all the cases [1,2], Group B Streptococcus (GBS) and E. coli are the leading pathogens.However, Klebsiella, Enterobacter, Citrobacter and Serratia species, Streptococcus pneumoniae, Listeria monocytogenes, Staphylococci aureus and coagulase-negative Staphylococci can also be diagnosed in some cases, but Neisseria meningitidis (N.meningitides) is not common in neonatal bacterial meningitis.There have been 48 cases of Neonatal Meningococcal Meningitis (NMM) described since the first case reported in 1916 [3].The incidence of NMM ranges from 0.8 to 1.3 per 100,000 in USA as reported.The spectrum of disease ranges from mild fever to fulminant septic shock, purpura fulminans, coma, and death.
Reported cases of meningitis caused by N. meningitidis and meeting the case definition were identified through a MEDLINE search of published articles.Clinical features, microbiologic results, treatments and outcome were recorded.

Case report
Meropenem and Ceftriaxone.A CSF culture was sterile.Real-time -PCR of the CSF proved the same causative agent as blood culture.Classification of the bacteria was confirmed by SunBioStar TM Multiplex Real-time PCR Detection Kit.It indicated that caused pathogen was N. meningitides, serogroup B.
Continued therapy with Penicillin and Cefotaxime were preceded due to the drug allergy testing.At the same time, the infant turned better both in clinical symptoms and CSF parameters.
Recheck CSF on the 4 th , 9 th , 15 th , 19 th , 25 th , 32 th , 37 th day prompted protein and WBC count of CSF decreased gradually (Figure 1).Recheck blood routine (Figure 2) indicated the infection was under control gradually.On the 33 rd hospital day, crianal Magnetic Resonace Imaging(MRI) showed long T1 and long T2 signal under the left skull, no expansion of the ventricular system, no shift of midline structures.After 37 days therapy, the baby was well response, and he was discharged from the hospital.
The infant was followed up at 3-month, 6-month, 9-month, and 1-year.He had made normal developmental progress.He could raised his head at 3-month, sit steady at 5.5-month.Intelligence test (Gesell) at 1 year was normal at his age.

Discussion
The common pathogens caused neonatal bacterial meningitis were E. coli, GBS, Listeria monocytogenes [1,2].Although N. meningitidis is a frequent cause of bacterial meningitis and sepsis during childhood, it is rare and causes a high rate of mortality during the neonatal period [17].The incidence of meningococcal infection in the general population is 0.8-1 per 100,000 in the United States [18], and 10 to 25 cases per 100,000 persons in the developing countries [19].Data from the Bacterial Core Surveillance Program indicated an annual incidence of 9 per 100,000 newborn infants [20].
N. meningitidis is a gram-negative β-proteobacterium and member of the bacterial family Neisseriaceae.It is not only a common bacterial commensal of the human upper respiratory tract (nasopharynx) but also an important and devastating human pathogen.Acquisition of meningococci through very close contact with respiratory secretions or saliva can be transient, lead to colonisation (carriage), or result in invasive disease.Meningitis is the most common clinical presentation of invasive meningococcal disease.Usual manifestations were fever, rash, a meningeal signs, and altered mental status, but these presentations were atypical in neonates, the boy in the present case got no rash through the process.Early diagnosis was difficult to make in new-born babies.Here, we described a neonate with meningococcal sepsis who was admitted to the hospital on postnatal day 17 with a fever, dispirited, and choking.
For therapy, early antibiotic treatment should be the primary goal, since effective antibiotics immediately stop the proliferation of N. meningitides [21].Recommended empirical antibiotics were Ampicillin (50-100 mg/ kg every 6 h) plus gentamicin (2.5 mg/ kg every 8 h), or cefotaxime (50 mg/ kg every 6-8 h) can be used in the setting of suspected Gram-negative bacilli [22].Proper drugs should be given right after the causative agent was definite.Duration of antimicrobial therapy for bacterial meningitis caused by N. meningitis was 7 days [23].Intravenous antimicrobial therapy is recommended for the duration of treatment to ensure that adequate CSF concentrations.In neonatal, duration of antibiotics was 2 weeks at least.Duration of antibiotics we reported the case was 37 days, because the WBC count of CSF dropped to normal until 2 weeks' therapy, glucose concentration rose to normal until 3 weeks' therapy, and subdural effusion was found on the 33th day, all these factors contributed to the "longterm" antimicrobial therapy.There were 37 cases reported in English literature (included our case) [1][2][3][4][5][6][7][8][9][10][11][12][13][14], 22 of them got serotypes.Serogroup B was found the most common serotype, so did our case.The vaccination of N.

Figure 2 :
Figure 2: Changes of WBC and CRP