新生儿败血症儿科教学.ppt

1、Neonatal Septicemia,Tongji Hospital,Bacteremia and Septicemia,Bacteremia: a more benign infection with entrance of bacteria into the bloodstream, but in limited quantities. Septicemia: an overwhelming infection with more organism or more virulent organisms that is likely to lead to shock or other co

2、mplications Term of (SIRS) The neonates does not localize infection well, and secondary spread to the meninges (meningitis) or other sites Incidence ranges from 110 patients per 1000 live births 1040% of mortality and substantial morbidity in survival,Etiology and Pathogenesis,Pathogen: varies with

3、region and time In USA and Europe: 1930s Group A Strep 1940s E. Coli 1950s Staph aureus 1970s Group B Strep In China: Staphylococcus, E. Coli Opportunistic pathogens Drug resistance,Route of Infection,Prenatal infection maternal bacteremia and septicemia invasive diagnostic procedures Intrapartum in

4、fection bacteria colonization in the parturient canal PROM, prolonged stages of labor Umbilical/fetal scalp sampling Postnatal infection enviroment, skin contact, medical procedures,Neonatal Vulnerability,Immature immune system skin/mucus membrane, low in IgG and complement, poor migration/phagocyto

5、sis, low in cytokine production Unavoidable pathogen exposure during birth Peripartum stress Invasive procedures Exposure to highly resistant nosocomial organisms,Clinical Manifestation,Most neonates with sepsis or meningitis present with NON SPECIFIC SIGNS OR SYMPTOMS Hypothermia/hyperthermia, resp

6、iratory distress, feeding difficulties, weak suck, irritability, lethargy, apnea, abdominal distension, vomiting, diarrhea, gallbladder distension, hepatosplenomegaly, jaundice, petechiae, seizure,General, GI, Respiratory, Renal, Cardiovascular, CNS, Hematological,Clinical Manifestation,Early-Onset

7、(03d7d) GBS E. Coli Listeria Others less common Herpes Staph aureus Strep A and D H. influenza Klebsiella Pseudomonas Enterobacter,Late-Onset (home)(828d) GBS Gram Negatives Herpes Late-Onset (hospital): Staph epidermidis Gram negatives (resistant) Pseudomonas, Klebsiella Enterobacter Serratia Acine

8、tobacter Candida (esp. if deep line),Laboratory Investigation,Screening Test (non-specific examination) WBC counts and differentiation, immature/total neutrophils ESR Acute phase proteins (CRP, etc) Pathogen Culture Blood culture CSF/urine culture (CNS and Urinary tract infection) Skin/secretion cul

9、ture Antigen for Pathogen Other Molecular Detection,Treatment,Antibiotics For infants with various high risk factors, clinical indications of infection, abnormal WBC, antibiotic therapy should be institute immediately without wait. Initial empirical treatment: ampicillin and an aminoglycoside (genta

10、micin or amikacin) ototoxicity! Nosocomial in NICU: nafcillin or Vancomycin Change according to drug sensitivity test Third-generation cephalosporins (eg Cefotaxime) Duration: 710 days, or 57 days after response, 14 days for meningitis A negative blood culture result does not preclude bacterial infe

11、ction Supportive Care: energy, liquid, maintain organ function,Complications and Prognosis,Complications of bacteremic infections: Endocarditis, septic emboli, abscess formation, septic joints with residual disability, osteomyelitis and bone destruction 50% mortality rate in adult, yet 20% in neonat

12、e (all bacteremic infections are included) Case fatality rate for neonatal bacterial meningitis is between 2025% Late complications of meningitis occurs in 4050% of survivors Hearing loss, abnormal behaviors, developmental delay, cerebral palsy, motor disability, seisure, hydrocephalus, etc.,Prevent

13、ion,Prevent intrauterine infections: maternal immunization Proper care of umbilical cord: tetanus, omphalitis Intrapartum chemoprophylaxis: GBS, Chlamydia Aggressive treatment of maternal chorioamnionitis Prevention of neonatal nosocomial infection: 2-min scrub before entering the nursery; 15-sec washing between pati