Isolation of Coxiella burnetii from serum of patients with acute Q fever

Gemma A Vincent; Stephen R Graves; Jennifer M Robson; Chelsea Nguyen; Hazizul Hussain-Yusuf; Aminul Islam; Stanley G Fenwick; John Stenos

doi:10.1016/j.mimet.2015.10.008

Isolation of Coxiella burnetii from serum of patients with acute Q fever

J Microbiol Methods. 2015 Dec:119:74-8. doi: 10.1016/j.mimet.2015.10.008. Epub 2015 Oct 14.

Authors

Gemma A Vincent¹, Stephen R Graves², Jennifer M Robson³, Chelsea Nguyen⁴, Hazizul Hussain-Yusuf⁴, Aminul Islam², Stanley G Fenwick⁵, John Stenos⁶

Affiliations

¹ Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia; Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia. Electronic address: gvince@barwonhealth.org.au.
² Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia; Pathology North-Hunter, NSW Health Pathology, Locked Bag 1, Hunter Region Mail Centre, New South Wales 2310, Australia.
³ Sullivan Nicolaides Pathology, Whitmore Street, Taringa, Queensland 4068, Australia.
⁴ Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia.
⁵ Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia; DAI, 93/1 GPF Witthayu Tower B, 12th Floor, Wireless Road, Lumpini, Pathamwan, Bangkok 10330, Thailand.
⁶ Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia; Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia.

PMID: 26462766
DOI: 10.1016/j.mimet.2015.10.008

Abstract

Worldwide there are few isolate collections of the intracellular bacterium Coxiella burnetii, due to the difficulties associated with working with the organism and the scarcity of suitable samples from which to attempt isolation. Particularly lacking are isolates from acute Q fever patients. The aim of this study was to evaluate whether the serum samples taken from patients with confirmed acute Q fever during the early stage of their disease represented a potential source of viable C. burnetii. Isolation was attempted from 65 of these samples by inoculation of the serum into Vero cell culture and was successful in 36 cases (55%). This high success rate was likely due to extended incubation of up to twelve weeks of the inoculated cultures, allowing the growth of the organism to levels detectable by PCR. Retrospective analysis of the time the sera was stored prior to inoculation into culture demonstrated that C. burnetii remained viable for 224 days in samples stored refrigerated and 371 days in samples stored frozen at -20 °C. These results demonstrate that standard serum samples taken from acute Q fever patients are a valuable source of new isolates of C. burnetii, with no special handling of the specimens required to maintain the organism's viability.

Keywords: Cell culture; Coxiella burnetii; Isolation; Q fever.

MeSH terms

Animals
Chlorocebus aethiops
Coxiella burnetii / genetics
Coxiella burnetii / growth & development
Coxiella burnetii / isolation & purification*
Humans
Q Fever / blood
Q Fever / diagnosis
Q Fever / microbiology*
Retrospective Studies
Serum / microbiology*
Vero Cells