G. Iacono et al., IGG ANTI-BETALACTOGLOBULIN (BETALACTOTEST) - ITS USEFULNESS IN THE DIAGNOSIS OF COWS MILK ALLERGY, The Italian Journal of Gastroenterology, 27(7), 1995, pp. 355-360
The aim of this prospective study was to evaluate the distribution of
serum values of IgG anti-betalactoglobulin in 3 groups of subjects: a)
218 healthy subjects (138 M, 80 F) with age ranging from 1 month to 6
years; b) 205 patients with cow's milk protein allergy (CMPA) (130 M,
75 F) aged between 1 month and 4 years; c) 96 patients (50 M, 46 F) w
ith symptoms compatible with CMPA, but suffering from other diseases (
age range 1 month-6 years), The IgG anti-betalactoglobulin values were
obtained using a new commercially available immunoenzymatic method, T
here was a marked difference in the distribution of IgG antibetalactog
lobulin values in the 3 study groups,In healthy controls the value cor
responding to the 5th centile was 5%, to the 50th centile 17%, to the
90th centile 48%. In the gastroenterological controls, 5th centile was
5%, 50th centile 15% and 90th centile was 56%, In the patients with C
MPA, 5th centile was 27%, 50th centile 101% and 90th was 147%, The dis
tribution of the values was therefore significantly different in the C
MPA group from that of the other 2 groups (p<0.0001). Plotting receive
r operating characteristic curves, we have indicated a betalactotest v
alue of 36% as a cutoff with the highest diagnostic accuracy (89% sens
itivity, 85% specificity). We suggest that the betalactotest should be
used to confirm diagnosis in patients with suspected CMPA; with a cut
-off of over 48% we found only one false positive for diagnosis of CMP
A in patients presenting other diseases with an identical clinical pic
ture,