IFNgamma and antibody responses among French nurses during a tuberculosis contact tracing investigation.
METHODS
A comparative study which compared PPD skin testing inserted according to the French Society of Pneumology's recommendations and interferon gamma release assay (IGRA) (QuantiFERON((R)) TB Gold In-tube, QF-TB-IT, Cellestis, Carnegie, Australia) was performed during a tuberculosis contact investigation in our hospital.


METHODS
Nineteen French health-care workers (HCWs) volunteered to participate. All of the HCW enrolled were BCG vaccinated and had a normal chest X-ray at entry.


RESULTS
Among the HCW, 68.4% were TST positive. By comparison, only 31.6% had a positive QF-TB-IT result. We took advantage of the negative tube and the corresponding plasma for antibody detection by ELISA. None were ELISA positive. Fourteen HCWs were followed up. None of the HCWs accepted a course of antiTB chemoprophylaxis. Despite the difficulty in establishing a trend in kinetics, we saw the complexity of interpretation of a dynamic T-cell response after contact with an index case.


CONCLUSIONS
This initial and first French picture provides us with the observation that only 44% of TST-positive HCW were IGRA positive, and the IGRA test allowed the detection of LTBI in two TST negative HCWs.
Herrmann
J-L
JL
Microbiology Department, Raymond Poincaré-Hospital, 104 Boulevard Raymond-Poincaré, 92380 Garches, France. jean-louis.herrmann@rpc.aphp.fr
Simonney
N
N
Bergeron
A
A
Ducreux-Adolphe
N
N
Porcher
R
R
Rouveau
M
M
Allez
M
M
Leportier
M
M
Tazi
A
A
Lemann
M
M
Lagrange
P-H
PH
D000328:Adult; D000906:Antibodies / Q000097:blood*; D000917:Antibody Formation; D001500:BCG Vaccine / Q000008:administration & dosage; D016358:Contact Tracing / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005602:France; D006801:Humans; D007371:Interferon-gamma / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D009726:Nurses; D013902:Radiography, Thoracic; D012307:Risk Factors; D012680:Sensitivity and Specificity; D014374:Tuberculin Test; D014376:Tuberculosis / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology*; D055815:Young Adult
D000906:Antibodies; D001500:BCG Vaccine; D007371:Interferon-gamma