Immunoglobulin M antibody responses to Mycobacterium ulcerans allow discrimination between cases of active Buruli ulcer disease and matched family controls in areas where the disease is endemic.
Buruli ulcer disease (BUD) is an emerging disease caused by Mycobacterium ulcerans. In the present study we have characterized the serological reactivities of sera from volunteer case patients with laboratory-confirmed BUD and controls living in three different regions of Ghana where the disease is endemic to determine if serology may be useful for disease confirmation. Our results showed highly reactive immunoglobulin G (IgG) responses among patients with laboratory-confirmed disease, healthy control family members of the case patients, and sera from patients with tuberculosis from areas where BUD is not endemic. These responses were represented by reactivities to multiple protein bands found in the M. ulcerans culture filtrate (CF). In contrast, patient IgM antibody responses to the M. ulcerans CF (MUCF) proteins were more distinct than those of healthy family members living in the same village. A total of 84.8% (56 of 66) of the BUD patients exhibited strong IgM antibody responses against MUCF proteins (30, 43 and 70 to 80 kDa), whereas only 4.5% (3 of 66) of the family controls exhibited such responses. The sensitivity of the total IgM response for the patients was 84.8% (95% confidence interval [CI], 74.3 to 91.6%), and the specificity determined with sera from family controls was 95.5% (95% CI, 87.5 to 98.4%). These studies suggest that the IgM responses of patients with BUD will be helpful in the identification and production of the M. ulcerans recombinant antigens required for the development of a sensitive and specific serological assay for the confirmation of active BUD.
Okenu
Daniel M N
DM
Emory University School of Medicine, Atlanta, Georgia 30303, USA.
Ofielu
Lazarus O
LO
Easley
Kirk A
KA
Guarner
Jeannette
J
Spotts Whitney
Ellen A
EA
Raghunathan
Pratima L
PL
Stienstra
Ymkje
Y
Asamoa
Kwame
K
van der Werf
Tjip S
TS
van der Graaf
Winette T A
WT
Tappero
Jordan W
JW
Ashford
David A
DA
King
C Harold
CH
D000907:Antibodies, Bacterial / Q000097:blood; D016022:Case-Control Studies; D019353:Endemic Diseases; D005192:Family Health; D005869:Ghana / Q000453:epidemiology; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D009165:Mycobacterium Infections, Nontuberculous / Q000175:diagnosis* / Q000453:epidemiology / Q000276:immunology*; D019911:Mycobacterium ulcerans / Q000276:immunology*; D012680:Sensitivity and Specificity; D012874:Skin Diseases, Infectious / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology; D012883:Skin Ulcer / Q000175:diagnosis / Q000453:epidemiology / Q000276:immunology
D000907:Antibodies, Bacterial; D007075:Immunoglobulin M