Indian Journal of Medical Microbiology IAMM  | About us |  Subscription |  e-Alerts  | Feedback |  Login   
  Print this page Email this page   Small font sizeDefault font sizeIncrease font size
 Home | Ahead of Print | Current Issue | Archives | Search | Instructions  
Users Online: 215 Official Publication of Indian Association of Medical Microbiologists 
  Search
 
 ~ Next article
 ~ Previous article 
 ~ Table of Contents
  
 ~  Similar in PUBMED
 ~  Search Pubmed for
 ~  Search in Google Scholar for
 ~  Article in PDF (29 KB)
 ~  Citation Manager
 ~  Access Statistics
 ~  Reader Comments
 ~  Email Alert *
 ~  Add to My List *
* Registration required (free)  

 
 ~  References

 Article Access Statistics
    Viewed4099    
    Printed87    
    Emailed2    
    PDF Downloaded255    
    Comments [Add]    

Recommend this journal

 


 
CORRESPONDENCE
Year : 2006  |  Volume : 24  |  Issue : 3  |  Page : 237-238
 

Incubation period for culture positivity to detect septicaemia in neonates


Department of Microbiology, Lady Hardinge Medical College, New Delhi - 110 002, India

Correspondence Address:
V S Randhawa
Department of Microbiology, Lady Hardinge Medical College, New Delhi - 110 002
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


PMID: 16912453

Rights and PermissionsRights and Permissions



How to cite this article:
Randhawa V S, Sherwal B L, Mehta G. Incubation period for culture positivity to detect septicaemia in neonates. Indian J Med Microbiol 2006;24:237-8

How to cite this URL:
Randhawa V S, Sherwal B L, Mehta G. Incubation period for culture positivity to detect septicaemia in neonates. Indian J Med Microbiol [serial online] 2006 [cited 2019 Jun 26];24:237-8. Available from: http://www.ijmm.org/text.asp?2006/24/3/237/27008


Dear Editor,

Apropos the correspondence published in the October 2005 issue of IJMM,[1] the crucial variables that affect the conclusion of four day processing period detecting positive blood cultures of virtually all important infections have not been mentioned.[2],[3] This could confuse the paediatricians and microbiologists on this important issue, as these variables vary from one laboratory to another. The variables that affect the blood culture reporting include whether the neonate is asymptomatic/symptomatic, automated/non automated (classical) blood culture detection and identification systems are used, volume of blood inoculated, number of blood cultures and the constitutents of the blood culture bottles.[2],[3] In this article, firstly no mention is made of the number of suspected sepsis neonates that were asymptomatic neonates suspected of having septicaemia require lesser observation period to rule out sepsis.[4] Secondly, no mention is made of the type of blood culture system used in the study, whether automated or non automated (classical). Using a newer version of automated blood culture and identification system, the time to detect a positive blood culture could be reduced, but even such a system could fail to detect bacteria in blood.[4],[5] This study did not mention the type of blood culture system used, but is able to recover and identify bacterial isolates is less than 24 hours. Such rapid results would be highly unlikely to obtain, using a non automated blood culture system. Thirdly, no mention is made of the amount of neonatol blood inoculated in the blood culture bottle, which is a critical factor in the diagnosis. Generally, increasing the amount of blood inoculated into a blood culture bottle, maintaining the optimal blood: broth ration, increase the isolation rate and the time to positivity.[2],[3]

Lastly, no mention is made of the constitutents of the blood culture bottles used in the study.[2],[3] Many laboratories in our use basal media as glucose broth instead of the recommended enriched media due the cost factor. This could increase the time to positivity in the blood cultures. Some laboratories expensive readymade media supplied by the companies which have proprietary additives to enhance the microbial growth, but equivalence among similar basic generic media from different commercial sources canto be assumed.[3] The other components usually added in the blood culture bottle as anticoagulant and additives to neutralize antimicrobials in blood culture bottle are not mentioned which can affect the isolation of different microbes. Therefore, a blood culture may be considered a 'gold standard' for sepsis, but the results of blood culture are better interpreted with reference to the different variables that affect its reporting.[4],[5]

 
 ~ References Top

1.Kumar CS, Neelagaud YF. Incubation period for culture positivity to detect septicaemia in neonates (correspondence). Indian J Med Microbiol 2005; 23: 270-1.  Back to cited text no. 1  [PUBMED]  [FULLTEXT]
2.O' Hara CM, Weinstein MP, Miller JM. Manual and automated systems for detection and identification of microorganisms, Chapter 14. In : Manual of Clinical Microbiology , 8th ed. Murray PR, Barron EJ, Pfaller MA, Jorgensen JH, Yolken RH, editors. (ASM Press, Washington DC) 2003. p. 185-207.  Back to cited text no. 2    
3.Wilson ML. Blood cultures. Clin Lab Med 1994; 14: 1-7.  Back to cited text no. 3  [PUBMED]  
4.Kumar Y, Qunibi M, Neal TJ, Yoxall CW. Time to positivity of neonatal cultures. Arch Dis Fetal Neonatal Ed 2001; 85 :F182-6.  Back to cited text no. 4  [PUBMED]  [FULLTEXT]
5.Klaerner HG, Eschenbach H, Kamereck K, Lehn, Wagner H, Miethke T. Failure of a automated blood culture system to detect non-fermentative gram-negative bacteria. J Clin Microbiol 2000; 38: 1036-41.  Back to cited text no. 5    




 

Top
Print this article  Email this article
Previous article Next article

    

2004 - Indian Journal of Medical Microbiology
Published by Wolters Kluwer - Medknow

Online since April 2001, new site since 1st August '04