Diagnosis of Helicobacter pylori infection by specific gastric mucosal IgA and IgG pylori antibodies.
OBJECTIVE
To investigate the diagnostic value of mucosal IgA and IgG Helicobacter pylori antibodies.


METHODS
The study population comprised 209 consecutive patients with severe dyspeptic complaints referred for upper gastrointestinal endoscopy. A positive culture or histological identification of H pylori in gastric biopsy specimens, or both, were used to confirm infection. Specific IgA and IgG H pylori antibodies were determined using a modified ELISA technique.


RESULTS
Of the 209 patients, 137 were infected with H pylori. The diagnostic value of systemic IgA and IgG H pylori antibodies was confirmed. Systemic IgA antibodies had a sensitivity of 76.6% (95% confidence interval 69.5-83.7) and a specificity of 94.4% (89.1-99.7). The sensitivity and specificity for systemic IgG antibodies were, respectively, 97.1% (94.3-99.9) and 98.6% (95.9-100). A moderate but clinically important correlation was found between local and systemic IgA and IgG. Mucosal IgA H pylori antibodies had a sensitivity of 98.5% (96.5-100) and a specificity of 91.7% (85.3-98.1), while for IgG these figures were, respectively, 88.3% (82.9-93.7) and 98.6% (95.9-100). As a diagnostic test mucosal IgA H pylori antibodies were comparable with culture and histology.


CONCLUSIONS
Determination of local IgA and IgG H pylori antibody levels is a highly sensitive and specific test for the diagnosis of H pylori infection.
Department of Gastroenterology and Hepatology, University Hospital Leiden, The Netherlands.
R A
RA
Veenendaal
J M
JM
Götz
V
V
Schroijen
F
F
Kurban
A T
AT
Bernards
M
M
Veselic
A S
AS
Peña
C B
CB
Lamers
D000328:Adult; D000907:Antibodies, Bacterial / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005753:Gastric Mucosa / Q000276:immunology*; D005756:Gastritis / Q000382:microbiology*; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
D000907:Antibodies, Bacterial; D007070:Immunoglobulin A; D007074:Immunoglobulin G