Coeliac disease is the life-long intolerance to dietary gluten, usuall
y characterized by severe damage to the small-intestinal mucosa. The w
idespread use of sensitive diagnostic tools, such as the serum anti-gl
iadin and the anti-endomysial antibodies, has shown not only that coel
iac disease is one of the commonest disorders in Western countries but
also that this condition is characterized by a higher degree of clini
cal variability than previously thought (typical, atypical and silent
forms). The existence of a latent-potential coeliac disease and even a
gluten-sensitive disease with immunological activation of an otherwis
e normal small-intestinal mucosa has recently been postulated. An incr
eased prevalence of coeliac disease in a number of other disorders has
also been reported in both children and adults. The reasons for such
a wide clinical heterogeneity are still poorly understood but are like
ly to depend on both genetic and environmental factors. Further invest
igations are required to evaluate the impact of undiagnosed, clinicall
y milder forms of coeliac disease on the well-being of the population.