Send letter to journal:
Re: More lumbar punctures, please!

Dear Editor

Applause to Kneen et al.[1] and Riordan and Cant[2] for reminding us of the value of lumbar puncture in suspected meningitis. To their arguments I would add that, while the matter may end after seven days' intravenous antibiotic treatment as far as the admitting paediatrician is concerned, it certainly does not for the child or parents of many children who have had meningitis, as recent data shows.[3] To be discharged home in ignorance or confusion regarding the diagnosis, as is becoming the norm, does no favours either to the patient or to anyone attempting to manage late complications. In adopting the "treat and do a hearing test" approach we should consider whether we are really motivated by a desire to relieve the child of the risk and discomfort of the procedure or to relieve ourselves of the bother. Undoubted risk and discomfort does not seem to have put us off requesting large numbers of head CT scans (often without contrast - so they do not reliably exclude abscess) in this clinical situation, even though they do not tell us anything useful about raised intracranial pressure.

As both papers point out, the epidemiology and management of bacterial meningitis are changing fast. Has anyone paused to consider how, in the future, we will evaluate either its incidence or the effectiveness of our current management strategies if we can't tell how many cases we have seen and who they were?

Clearly, it can be ill-advised to perform a lumbar puncture at the outset in seriously sick children - but there is always a time later on when the procedure can be done safely, and often also painlessly just before weaning from the ventilator.

As for the habit of replacing the LP (and other necessary investigations) with indiscriminate initiation of cephalosporin treatment in the mild to moderately ill febrile child, this simply encourages misdiagnosis and promotes development of antibiotic resistance.

Adam Finn
Professor of Paediatrics
University of Bristol

References

(1) Kneen R, Solomon T, and Appleton R. The role of lumbar puncture in suspected CNS infection—a disappearing skill? Arch Dis Child 2002;87:181-183.

(2) Riordan FAI and Cant AJ. When to do a lumbar puncture. Arch Dis Child 2002;87:235-237.

(3) Bedford H, de Louvois J, Halket S, Peckham C, Hurley R and Harvey D. Meningitis in infancy in England and Wales: follow up at age 5 years. Br Med J 2001;323:533-6.

Send letter to journal:
Re: LP and Glasgow coma score

Dear Editor

Congratulations to the authors on a balanced article on the need for lumbar puncture.

One point of possible confusion is the Glasgow Coma Score (GCS) quoted as a contraindication to LP. Kneen et al. quote a GCS <13 as a contraindication to LP, which would exclude a very large number of childen with meningitis. Riordan & Cant[1] in the same issue of your journal quote a GCS <8. Rennick et al[2] also use a GCS<8 as their cut-off figure in their hospital, as do we.[3]

There is little evidence to my knowledge. A retrospective Manchester study [4] found that children with GCS <8 were more likely to die from coning than other children with meningitis (relative risk 4.6, 95 % CI 1.06 to 35.8).

I would welcome comments from the authors and others as to whether they have better evidence for the GCS they quote, and if not, what we should advise in the absence of good evidence.

References

(1) Riordan FAI, Cant AJ. When to do a lumbar puncture. Arch Dis Child 2002;87:235-7.

(2) Rennick G, Shann F, de Campo J. Cerebral herniation during bacterial meningitis in children. BMJ 1993;306: 953-5.

(3) Kilham H, Isaacs D. The New Children's Hospital Handbook. NCH, Sydney, 1999. ISBN 0-9587167-1-4.

Send letter to journal:
Re: LP: contraindications

Dear Editor

I read the article and the two responses regarding the declining practice of lumbar puncture in children with CNS infections.[1-3] Yes, it is true that the number of LPs (lumbar punctures) have become less and less over the years in the developed countries. However, LB is still practiced as a common investigative procedure in suspected CNS infections in these countries, even in the presence of definitive contraindications for it. Though the deaths in such situations can not be confirmed to be directly related related to the procedure, because of the financial constraints; a definite, unambiguious protacol for the procedure will help prevent the deaths related to the procedure, whatever may be its true incidence.

References

(1) Kneen R, Solomon T and Appleton R. The role of lumbar puncture in suspected CNS infection—a disappearing skill? Arch Dis Child 2002;87:181-183.

(2) Finn A. More lumbar punctures, please! [electronic response to Kneen R et al., The role of lumbar puncture in suspected CNS infection—a disappearing skill?] archdischild.com 2002 http://adc.bmjjournals.com/cgi/eletters/archdischild;87/3/181#340

(3) Isaacs D. LP and Glasgow coma score [electronic response to Kneen R et al., The role of lumbar puncture in suspected CNS infection—a disappearing skill?] archdischild.com 2002 http://adc.bmjjournals.com/cgi/eletters/archdischild;87/3/181#344

Send letter to journal:
Re: Author's reply

Dear Editor

We thank Dr Isaacs for his helpful letter. He rightly points out that the published recommendations as to which Glasgow Coma Scale score serves as a contraindication to a lumbar puncture vary between < 8 and < 13, though we are not aware of any definitive evidence supporting either value. For the purposes of our overview commentary we chose the most conservative value (<13), which is also that recommended in the Advanced Paediatric Life Support Manual produced by the RCPCH advisory committee. Opinions will vary as to what level of consciousness is a contraindication to LP. In our clinical practice we do perform LPs on children with lower coma scores if there are no other contraindications to LP. These issues clearly deserve further consideration, but for this Editorial our primary concern related to the observation that even many fully conscious children do not undergo LP for the spurious reasons outlined in our article.

In the Editorial we refer to a survey of LP practice in Liverpool, which were unpublished observations at the time; these data have now also been published.[1].

References

(1) Kneen, R, Solomon T, Appleton RE. The role of lumbar puncture in children with suspected central nervous system infection. BMC Pediatrics 2002, 2:8.
This article is available free online from:http://www.biomedcentral.com

Send letter to journal:
Re: Defer and practise

Dear Editor

1. Defer
I am a Registrar who used to lumbar puncture (LP) almost anyone febrile under a year, but then swung to the opposite extreme. Nowadays I decide on the balance of risk based on my clinical experience.The decision on whether to perform a LP should be taken by an experienced paediatrician, but this does not need to be the moment the child arrrives in A&E. Is there anything to be lost in a child where there is reticence to doing a LP on admission (for whatever reason), to do one the following morning? Many children have already received antibiotics from their GP prior to admission, so doing the LP after a further couple of doses will surely make little difference to the chance of a positive culture, but the cell count is still helpful. And of course, there is that magical PCR.

2. Practise
Anyone who needs practise performing LPs should pop along to their local oncology ward. Here, under the most controlled of settings, they can be taught and practice this important skill.