J Med Microbiol International Journal of Systematic and Evolutionary Microbiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Ganoza, C. A.
Right arrow Articles by Guerra, H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Ganoza, C. A.
Right arrow Articles by Guerra, H.
Agricola
Right arrow Articles by Ganoza, C. A.
Right arrow Articles by Guerra, H.
J Med Microbiol 57 (2008), 1094-1098; DOI: 10.1099/jmm.0.2008/001339-0
© 2008 Society for General Microbiology
ISSN 1473-5644

Novel hypertonic saline–sodium hydroxide (HS–SH) method for decontamination and concentration of sputum samples for Mycobacterium tuberculosis microscopy and culture

Christian A. Ganoza1,{dagger}, Jessica N. Ricaldi1, José Chauca1, Gabriel Rojas1, César Munayco2, Juan Agapito3, Juan Carlos Palomino4 and Humberto Guerra1

1 Laboratorio de Microbiología Clínica, Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia, Lima, Peru

2 Laboratorio de Micobacteriología, Oficina General de Epidemiología, Ministerio de Salud, Lima, Peru

3 Programa Nacional para el Control de la Tuberculosis, Hospital Nacional Cayetano Heredia, Lima, Peru

4 Mycobacteriology Unit, Prince Leopold Institute of Tropical Medicine, Antwerp, Belgium

Correspondence
Christian A. Ganoza
03896{at}upch.edu.pe

Received 15 February 2008
Accepted 12 May 2008

This study evaluated a new decontamination and concentration (DC) method for sputum microscopy and culture. Sputum samples from patients with suspected pulmonary tuberculosis (TB) (n=106) were tested using the proposed hypertonic saline–sodium hydroxide (HS–SH) DC method, the recommended N-acetyl-L-cysteine–sodium citrate–sodium hydroxide (NALC-NaOH) DC method and unconcentrated direct smear (Ziehl–Neelsen) techniques for the presence of mycobacteria using Löwenstein-Jensen culture and light microscopy. Of 94 valid specimens, 21 (22.3 %) were positive in culture and were further characterized as Mycobacterium tuberculosis. The sensitivity for acid-fast bacilli (AFB) smears was increased from 28.6 % using the direct method to 71.4 % (HS–SH) and 66.7 % (NALC-NaOH) using DC methods. Both concentration techniques were highly comparable for culture (kappa=0.794) and smear (kappa=0.631) for AFB. Thus the proposed HS–SH DC method improved the sensitivity of AFB microscopy compared with a routine unconcentrated direct smear; its performance was comparable to that of the NALC-NaOH DC method for AFB smears and culture, but it was methodologically simpler and less expensive, making it a promising candidate for evaluation by national TB control programmes in developing countries.

Abbreviations: AFB, acid-fast bacilli; DC, decontamination and concentration; HS–SH, hypertonic saline–sodium hydroxide; NALC-NaOH, N-acetyl-L-cysteine–sodium citrate–sodium hydroxide; NTP, National Tuberculosis Control Program; TB, tuberculosis.

{dagger}Present address: Department of Immunology, Max Planck Institute for Infection Biology, Charitéplatz 1, 10117 Berlin, Germany.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
INT J SYST EVOL MICROBIOL J MED MICROBIOL MICROBIOLOGY J GEN VIROL ALL SGM JOURNALS
Copyright © 2008 Society for General Microbiology.