Looking for celiac disease: diagnostic accuracy of two rapid commercial assays.
BACKGROUND
Early diagnosis and treatment with gluten-free diet reduces mortality and the prevalence of associated disorders in celiac disease (CD). A simple "in the office" test of anti-transglutaminase antibodies might be of great help in first-line screening for CD.


OBJECTIVE
We evaluated the sensitivity and specificity of two commercial kits based, respectively, on rapid detection of IgA-IgG anti-human-transglutaminase antibodies (anti-h-tTG) in serum and IgA anti-h-tTG antibody in one drop of whole blood. These assays were compared to a well-established enzyme-linked immunosorbent assay technique.


METHODS
Serum samples were analyzed from 114 biopsy-confirmed celiacs, 120 healthy controls, 20 first-degree relatives of celiacs, and 75 diseased controls. The whole blood samples were analyzed from 51 biopsy-confirmed celiacs and 100 controls.


RESULTS
The serum-based test was positive in all 114 celiacs (sensitivity 100%). Among the controls there were seven healthy blood donors, one first-degree relative, and three diseased controls who tested positive (specificity 94.9%). The blood drop-based assay testing IgA antibodies was positive in 46 of 51 (sensitivity 90.2%), and since three of the five patients testing negative had total IgA deficiency, the sensitivity value can be increased to 95.8%. All 100 controls tested negative (specificity 100%).


CONCLUSIONS
The commercial kits described here produce high values of sensitivity and specificity, offering the general practitioner who suspects a possible case of CD the real possibility to look for anti-h-tTG antibodies in his own medical office during a standard visit at a satisfyingly low cost.
Nemec
Gregor
G
Department of Reproductive and Development Science, Institute of Child Health I.R.C.C.S. Burlo Garofolo, Italy.
Ventura
Alessandro
A
Stefano
Martelossi
M
Di Leo
Grazia
G
Baldas
Valentina
V
Tommasini
Alberto
A
Ferrara
Fortunato
F
Taddio
Andrea
A
Città
Angelo
A
Sblattero
Daniele
D
Marzari
Roberto
R
Not
Tarcisio
T
D002446:Celiac Disease / Q000097:blood / Q000175:diagnosis*; D042241:Early Diagnosis; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D011503:Transglutaminases
D007070:Immunoglobulin A; D007074:Immunoglobulin G; D011933:Reagent Kits, Diagnostic; D011503:Transglutaminases