Celiac Disease - NIH Consensus Development Program - National ...

The Many Faces of Celiac Disease: Clinical Presentationof Celiac Disease in the Adult PopulationPeter H. R. Green, M.D.The presentation of adults with celiac disease can be broadly divided in two types: theclassical diarrhea-predominate type and the silent type in which gastrointestinal symptoms arenot prominent. (1) The latter group includes patients that may present with secondarymanifestations of celiac disease (e.g., anemia or osteoporosis), associated autoimmune diseases(type 1 diabetes or peripheral neuropathy), or associated malignancies. The silent group includesthose that are asymptomatic, and detected by screening relatives of patients with celiac disease.The lag between the clinical prevalence (2) and the serologic prevalence (3) of celiac disease(the iceberg phenomenon) in the United States demonstrates that most people with celiac diseaseare currently not diagnosed and probably have the silent form of celiac disease. This wasconfirmed in a population-based screening study from England in which those with undetectedceliac disease (1.2 percent of those screened) had mild anemia, osteoporosis, and low serumcholesterol values and considered themselves well, and had a trend to participate in lesscardiovascular events. (4)Celiac disease is a proximal small intestinal inflammatory disease that may involve avariable length of the intestine. The proximal intestine is the site of absorption of iron, calcium,fat-soluble vitamins, and folic acid, as well as the products of the digestion of fats,carbohydrates, and proteins. When limited to the proximal intestine, vitamins and mineralsusually absorbed may be selectively malabsorbed; however, diarrhea may not occur because thedistal small intestine can compensate and absorb the products of the digestion of fats andcarbohydrates. The length of intestine involved is more important than the degree of villousatrophy present in duodenal biopsies in determining whether diarrhea will occur. Other factorscontributing to diarrhea include a reversible pancreatic insufficiency, secondary lactoseintolerance, and bacterial overgrowth.In view of the lack of information about the clinical spectrum of celiac disease in theUnited States, we conducted a survey to obtain data. Information from more than 1,600 patientswas obtained. This study confirmed a female predominance over males (3:1). The majority ofpatients were diagnosed in their fourth to sixth decades and 85 percent presented with diarrhea.The mean duration of symptoms prior to diagnosis was 11 years. (5) This delay in diagnosis is notunique to the United States and is considered to be physician-based rather than due to delay inpatients seeking health care. (6) A contributing factor is that patients receive alternative diagnosessuch as an irritable bowel syndrome. (7)Two studies have shown a relative decrease in the percent of patients presenting withdiarrhea, though it remains the most common mode of presentation accounting for about50 percent of patients. (2,8) The increasing availability of serologic testing may contribute to boththe increased rate of diagnosis and to diagnosis of patients with nondiarrheal presentations.Despite an increased rate of diagnosis, patients still experience a long duration of symptoms65