Isolation of Francisella tularensis by centrifugation of shell vial cell culture from an inoculation eschar.
A 52-year-old man was admitted to the hospital following the development of an inoculation eschar and fever six days after being bitten by a tick. He was clinically diagnosed as suffering from rickettsiosis. Eschar biopsy cultures on standard bacteriological media remained sterile. However, inoculation of cells with the homogenized specimen by the centrifugation-shell vial technique (M. Marrero and D. Raoult, Am. J. Trop. Med. Hyg. 40:197-199, 1989) resulted in the recovery of a bacterium. Determination of the sequence of the 16S rRNA gene amplified from the organism and comparison of the sequence to other sequences identified it as a strain of Francisella tularensis, whereas the specific serology was still negative. Our findings demonstrate that the centrifugation-cell culture, which is a tool for investigation of tick-transmitted diseases, may have the potential to serve as a method for the cultural isolation of F. tularensis.
Unité des Rickettsies, CNRS:UPRESA 6020, Faculté de Médecine, Université de la Méditerranée, 13385 Marseille Cedex 05, France.
P E
PE
Fournier
L
L
Bernabeu
B
B
Schubert
M
M
Mutillod
V
V
Roux
D
D
Raoult
D000818:Animals; D001706:Biopsy; D001733:Bites and Stings / Q000382:microbiology*; D002498:Centrifugation / Q000379:methods; D003937:Diagnosis, Differential; D005604:Francisella tularensis / Q000235:genetics* / Q000302:isolation & purification*; D005784:Gene Amplification; D006801:Humans; D008297:Male; D008875:Middle Aged; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012282:Rickettsia Infections / Q000175:diagnosis; D013987:Ticks; D014406:Tularemia / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology
D012336:RNA, Ribosomal, 16S