[Detection of serum IgG (ELISA) against Helicobacter pylori: relationship with age and gastroduodenal disease].
OBJECTIVE
An attempt was made to investigate the serological response against Helicobacter pylori by using a IgG serum detection technique (ELISA Biometra) to establish a relationship with age and gastroduodenal pathology. The serological response was compared with the microbiologic and histologic studies of biopsy samples from 4 locations in each patient: duodenal bulb, gastric antrum, corpus and fundus.


METHODS
A total of 309 patients with gastrointestinal symptoms who underwent an upper digestive endoscopy were included.


RESULTS
The overall sensitivity of the serological technique (cut-off value 15 U/ml) was 89.3%, the specificity 75.7%, the positive predictive value 96.9% and the negative predictive value 45.4%. The mean titer in patients with a negative microbiology increased with age: 13.5 U/ml, 14-30 years; 10.0 U/ml, 31-50 years; 18.5 U/nl, 51-65 years and 29.2 U/ml, > 65 years. By increasing the cut-off value to 20 and 30 U/ml in the last two age groups, the specificity increased without a significant decrease in the sensitivity. Patients without abnormal findings at endoscopy had mean titers considerably lower (64.7 U/ml) than those with the stomach resected -Billroth I or II- (99.6 U/ml) and those with gastritis, duodenitis and ulcus (86.7-83.1 U/ml), Patients with gastritis but without acute inflammatory activity had mean titers (62.5 U/ml) lower than those observed in patients with active gastritis (p < 0.01) and increased in parallel with the increasing activity of gastritis. In contrast, patients with atrophic gastritis had the lowest mean titers (54 U/ml).


CONCLUSIONS
Our results suggest that the cut-off value in the serological technique should be increased according to the patient's age. Moreover, there is a clear relationship between the serum levels of IgG and the activity of gastritis.
Pozuelo
M J
MJ
Servicio de Microbiología, Hospital Ramón y Cajal, Madrid.
Martín de Argila
C
C
Cantón
R
R
Ballestero
S
S
de Rafael
L
L
Alvarez-Baleriola
I
I
Pérez-Gisbert
J
J
Boixeda
D
D
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000907:Antibodies, Bacterial / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005767:Gastrointestinal Diseases / Q000097:blood / Q000382:microbiology; D016481:Helicobacter Infections / Q000097:blood*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
D000907:Antibodies, Bacterial; D007074:Immunoglobulin G
Detección de IgG sérica (ELISA) frente a Helicobacter pylori: relación con la edad y patología gastroduodenal.