Visser et al (1980), Kansas City, USA3 | 400 neonates of whom 193 babies had concurrent blood and CSF cultures for suspected late onset (>72 h) sepsis Gestation: 25–42/40 Birth weight: 634–5650 g | Retrospective cohort (level 2b) | Prevalence of positive CSF culture in the study group | 2.5% (5/193) CSF samples positive 10% (21/193) blood cultures positive 24% of septic babies had meningitis (5/21) 15% had concurrently negative blood cultures No reported adverse effects | Meningitis likely to be under diagnosed as retrospective study All babies with suspected sepsis had lumbar punctures performed routinely before antibiotics were started |
Schwersenski et al (1991), Miami, USA2 | 826 neonates who underwent an LP, out of which 114 had LPs performed at greater than 1 week of age (late onset) Birth weight: less than 1500 g to greater than 2500 g | Prospective (level 1b) | Prevalence of positive CSF culture in study group | 3.5% (4/114) had meningitis. There were 8 positive CSF cultures, but 4 were considered contaminants 25% (1/4) had concurrently negative blood cultures No reported adverse effects | Included LPs done for post haemorrhagic hydrocephalus with raised ICP (8) Under estimation of meningitis as babies >72 h but <1 week, included in early onset |
Hristeva et al (1993), Oxford, UK1 | 736 babies underwent an LP, of which 225 had LPs performed late (at >48 h of age) 88 of these were <31 weeks gestation | Prospective (level 1b) | Prevalence of positive CSF culture in study group | 1.3% (4/310) cultures were positive Of 88 babies <31 weeks, 6 had late meningitis (4 bacterial;2 fungal) i.e. 6.8% prevalence (personal correspondence with authors) No mention of number of concurrent negative blood cultures 1 case of probable post-traumatic meningitis reported | High proportion of babies had an LP (42% of all admissions) Babies with respiratory distress had LPs deferred, thereby possibly underestimating the adverse effect |
Kumar et al (1995), India4 | 169 neonates who underwent an LP for suspected sepsis (119 of which were late onset) Gestational: <33–>36/40 Birth weight: <1500 g–>2500 g | Prospective (level 1b) | Prevalence of positive CSF culture in study group | 3.3% (4/119) had positive CSF findings 11% had positive blood cultures All babies with meningitis had negative blood cultures No adverse effects of LP reported | Extensive antibiotic use present due to the higher risk population and this may underestimate incidence of meningitis Late onset clearly defined. Appears to be >7 days |
Stoll et al (2004), USA5 | 2877/9641 (30%) had LP>72 h and 6056 (63%) had blood cultures at >72 h Gestation: <25–>33/40 Birth weight: >400–1500 g Average age at LP: 22 days (median: 16 days, range: 4–120 days) | Prospective multi-centre study (level 1b) | Prevalence of positive CSF culture in study | 2.2% (134/6056) had positive CSF cultures 5% (134/2877) of all lumbar punctures were positive (not all septic babies had lumbar punctures) 7.2% of those with positive blood cultures had meningitis 30% (45/134) with meningitis had negative blood cultures Babies with meningitis (compared to those uninfected) were: – ventilated longer (28 v 18 days) – in hospital longer (91 v 79 days) – more likely to fit (25% v 2%) – more likely to die (23% v 2%) There was no difference in the risk of death between infants who did and did not have lumbar punctures [284/2877 (10%) v 661/6764 (10%)] | Study included only very low birth weight babies (<1500 g). This might overestimate risk as the VLBW is the susceptible population 11% of LPs repeated within 10 days were positive for the same organism even though the babies were on treatment with antibiotics |