Diagnosis of coeliac disease what else can be done

[kickingfrog]

Diagnosis of coeliac disease: what else can be done

bmj 14 April 2005

Federico Marchetti,
Clinical Paediatrician
Clinica Pediatrica, IRCCS Burlo Garofolo, Università di Trieste, via dell'Istria 65/1, 34100 Trieste,
Tarcisio Not, Jenny Bua, Alessandro Ventura


EDITOR- We read with interest the editorial by Peter Watson on the diagnosis of coeliac disease in a recent issue of the journal (1). Peter Watson describes how to proceed when the diagnosis of coeliac disease is in doubt; that is, in the case of negative antibody testing with suggestive histological findings for coeliac disease, or in the case of positive antibody testing with normal histological findings.
Notably, however, no consideration is given to genetic examinations, such as class II HLA determination.
Coeliac disease is strongly associated with specific class II HLA loci.
Overall, more than 95% of patients with coeliac disease have either HLA DQ2 or HLA DQ8 (2).
Although one third of the general population is a healthy carrier of one of these HLA loci, we believe that their determination is very useful when the diagnosis is in doubt. When the histology is suggestive for coeliac disease but anti-endomysial, anti- gliadin and anti-transglutaminase antibodies are negative, the absence of HLA-DQ2/DQ8 indicates an alternative diagnosis.
On the other hand, when a patient tests positive for anti-endomysial, anti-gliadin and anti- transglutaminase antibodies but has apparently normal histological findings, class II HLA determination can be useful in selecting those patients who need to be followed up.
Finally, in high risk patients, such as 1st and 2nd degree relatives of patients with coeliac disease, patients with type I diabetes, or Down syndrome etc, the presence of HLA DQ2 or DQ8 suggests, at least in the first years of life, to follow them up with periodic antibodies testing, since it is in these patients that coeliac disease may develop when the high risk HLA loci are present (3,4).
Finally, since the spectrum of histological alterations suggestive for coeliac disease varies from inflammatory infiltrate to villous atrophy, in the patients with highly suggestive clinical symptoms but normal histological findings, immunohystochemical analyses on the bioptical specimen should be always performed in order to determine the expected increased concentration of CD3 and gamma delta positives lymphocytes (5).

References
1. Peter Watson RG Diagnosis of coeliac disease BMJ 2005;330:739-740
2. Kaukinen K, Partanen J, Maki M, Collin P. HLA-DQ typing in the diagnosis of celiac disease Am J Gastroenterol 2002;97(3):695-9
3. Hoffenberg EJ, Bao F, Eisenbarth GS, Uhlhorn C, Haas JE, Sokol RJ, Rewers M. Transglutaminase antibodies in children with a genetic risk for celiac disease. J Pediatr. 2000;137(3):356-60.
4. Csizmadia CG, Mearin ML, Oren A, Kromhout A, Crusius JB, von Blomberg BM, Pena AS, Wiggers MN, Vandenbroucke JP. Accuracy and cost- effectiveness of a new strategy to screen for celiac disease in children with Down syndrome. J Pediatr.2000;137(6):756-61.
5. Jarvinen TT, Collin P, Rasmussen M, Kyronpalo S, Maki M, Partanen J, Reunala T, Kaukinen K Villous tip intraepithelial lymphocytes as markers of early-stage coeliac disease. Scand J Gastroenterol 2004;39(5):428-33.
Federico Marchetti, clinical paediatrician
[e-mail]
Tarcisio Not, clinical paediatrician
Jenny Bua, resident in paediatrics
Alessandro Ventura, Director
Clinica Pediatrica, IRCCS Burlo Garofolo, Università di Trieste, via dell’Istria 65/1, 34100 Trieste
Competing interests: None declared




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