Further studies of anti-endomysium and anti-gliadin antibodies in patients with suspected celiac disease.
BACKGROUND
The finding of characteristic small intestinal mucosal abnormalities on histologic examination of a biopsy specimen remains the first requirement for the diagnosis of celiac disease. A reliable and noninvasive test would be ideal for the patient's convenience and for reducing health-care costs. The sensitivity and specificity of anti-gliadin antibodies (AGA-immunoglobulin [Ig] G, AGA-IgA) have been variable; anti-endomysium IgA (EmA-IgA) is more helpful. In an earlier study conducted at the authors' institution, celiac disease was present in 19 patients examined from 1992 to 1995. Anti-endomysium titers were higher than normal in all 19 patients (100%). Total villous atrophy was seen in 14 of 17 biopsy specimens (82%) and subtotal atrophy in 3 (18%). The purpose of the current study was to evaluate further the accuracy of EmA-IgA in diagnosing celiac disease.


METHODS
One hundred seven patients were screened for celiac disease between March 1996 and July 1997. The level of EmA-IgA was measured in all patients, and AGA-IgG and AGA-IgA were measured in 104 patients. Forty-six patients underwent endoscopic biopsy of the small bowel, with measurement of disaccharidase enzymes in 45 patients.


RESULTS
Five of 46 patients had celiac disease (three boys and two girls; mean age, 5.3 years; 2-9.5 years); one also had cystic fibrosis and another had insulin-dependent diabetes mellitus. All five had marked to complete villous atrophy with crypt hyperplasia and increased serum EmA-IgA (100% sensitivity). None of the remaining patients had increased EmA-IgA (100% specificity). Serum levels of AGA-IgG and AGA-IgA were increased in all four celiac disease patients (100% sensitivity), but they were also high in patients without celiac disease (38% and 92% specificity, respectively), which compromises their diagnostic value. None of the patients confirmed to have celiac disease had IgA deficiency. Abnormal disaccharidase enzyme activities were documented in all five celiac disease patients: severe generalized deficiency (n = 2), moderately severe generalized deficiency (n = 2), and alactasia with moderate deficiency of the alpha-glucosidases (n = 1).


CONCLUSIONS
This study confirmed the reliability and accuracy of EmA-IgA in the diagnosis of celiac disease. Small bowel biopsy may be unnecessary in EmA-positive patients in whom celiac disease is suspected.
Division of Gastroenterology-Hepatology-Nutrition, James Whitcomb Riley Hospital for Children, Indiana University Medical Center, Indianapolis 46202-5225, USA.
M A
MA
Del Rosario
J F
JF
Fitzgerald
S K
SK
Chong
J M
JM
Croffie
S K
SK
Gupta
D000906:Antibodies / Q000097:blood*; D001323:Autoantibodies / Q000097:blood*; D002446:Celiac Disease / Q000150:complications / Q000276:immunology* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000150:complications; D003922:Diabetes Mellitus, Type 1 / Q000150:complications; D004386:Duodenum / Q000473:pathology; D005260:Female; D005903:Gliadin / Q000276:immunology*; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D018485:Muscle Fibers, Skeletal / Q000276:immunology*
D000906:Antibodies; D001323:Autoantibodies; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D005903:Gliadin