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
Services
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 arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Nace, E. K.
Right arrow Articles by Eberhard, M. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Nace, E. K.
Right arrow Articles by Eberhard, M. L.

 Previous Article  |  Next Article 

Journal of Clinical Microbiology, December 1999, p. 4113-4119, Vol. 37, No. 12
0095-1137/99/$04.00+0

Evaluation of Streck Tissue Fixative, a Nonformalin Fixative for Preservation of Stool Samples and Subsequent Parasitologic Examination

Eva K. Nace,* Frank J. Steurer, and Mark L. Eberhard

Division of Parasitic Diseases, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Services, Atlanta, Georgia 30341

Received 23 June 1999/Returned for modification 24 July 1999/Accepted 20 August 1999

We undertook a study to evaluate Streck tissue fixative (STF) as a substitute for formalin and polyvinyl alcohol (PVA) in fecal preservation. A comparison of formalin, PVA, (mercuric chloride based), and STF was done by aliquoting fecal samples into each fixative. Stool specimens were collected in Haiti, and parasites included Cyclospora cayetanensis, Giardia intestinalis, Entamoeba coli, Iodamoeba butschlii, Endolimax nana, Ascaris lumbricoides, Trichuris trichiura, Strongyloides stercoralis, and Necator americanus. Preserved stools were examined at various predetermined times (1 week, 1 month, and 3 months) to establish the quality of the initial preservation as well as the suitability of the fixative for long-term storage. At each time point, stool samples in fixatives were examined microscopically as follows: (i) in wet mounts (with bright-field and epifluorescence microscopy), (ii) in modified acid-fast-, trichrome-, and safranin-stained smears, and (iii) with two commercial test kits. At the time points examined, morphologic features remained comparable for samples fixed with 10% formalin and STF. For comparisons of STF- and 10% formalin-fixed samples, specific findings showed that Cyclospora oocysts retained full fluorescence, modified acid-fast- and safranin-stained smears of Cryptosporidium and Cyclospora oocysts were equal in staining quality, and results were comparable in the immunofluorescence assay and enzyme immunoassay commercial kits. Stool fixed in STF and stained with trichrome showed less-than-acceptable staining quality compared with stool fixed in PVA. STF provides an excellent substitute for formalin as a fixative in routine examination of stool samples for parasites. However, modifications to the trichrome staining procedures will be necessary to improve the staining quality for protozoal cysts fixed in STF to a level comparable to that with PVA.


* Corresponding author. Mailing address: Div. Parasitic Diseases/F-13, CDC, 4770 Buford Hwy., N.E., Atlanta, GA 30341-3724. Phone: (770) 488-4414. Fax: (770) 488-4253. E-mail: ebk5{at}cdc.gov.


Journal of Clinical Microbiology, December 1999, p. 4113-4119, Vol. 37, No. 12
0095-1137/99/$04.00+0



This article has been cited by other articles:

  • Hata, J., Ikeda, E., Uno, H., Asano, S. (2002). Expression of Hepatocyte Growth Factor mRNA in Rat Liver Cirrhosis Induced by N-nitrosodimethylamine as Evidenced by In Situ RT-PCR. J. Histochem. Cytochem. 50: 1461-1468 [Abstract] [Full Text]  
  • Fedorko, D. P., Williams, E. C., Nelson, N. A., Calhoun, L. B., Yan, S. S. (2000). Performance of Three Enzyme Immunoassays and Two Direct Fluorescence Assays for Detection of Giardia lamblia in Stool Specimens Preserved in ECOFIX. J. Clin. Microbiol. 38: 2781-2783 [Abstract] [Full Text]  
  • Pietrzak-Johnston, S. M., Bishop, H., Wahlquist, S., Moura, H., Da Silva, N. D. O., Da Silva, S. P., Nguyen-Dinh, P. (2000). Evaluation of Commercially Available Preservatives for Laboratory Detection of Helminths and Protozoa in Human Fecal Specimens. J. Clin. Microbiol. 38: 1959-1964 [Abstract] [Full Text]