Celiac Disease

Mechanism

Celiac disease is caused by the ingestion of gluten in genetically susceptible individuals in whom an immune reaction to gluten damages the small intestinal mucosa. The trigger of the immune reaction and the mechanism of damage have not been fully elucidated. In celiac disease, the villi, which are the finger-like projections in the intestine and the lining of the intestine (enterocytes), are damaged, reducing the surface available for nutrient absorption.

Symptoms

Celiac symptoms can manifest only when gluten is ingested by genetically susceptible individuals. Symptoms can be subtle, delayed, or absent; may vary in number, range, and intensity; and include intestinal as well as extraintestinal symptoms. The complexity of symptoms and variety can be elusive, and the diagnosis may be missed. Symptoms in children can include malodorous, bulky, pale-colored stools, diarrhea, growth retardation, weight loss, anorexia, poor appetite, irritability, abdominal discomfort, abdominal distension, or emesis (vomiting). Symptoms in adults can include abdominal pain, bloating, muscle cramps, anemia, depression, fatigue, irritability, diarrhea, emesis, involuntary weight loss, osteoporosis, osteopenia, steatorrhea, foul-smelling stool, and dermatitis herpetiformis. There are individuals with celiac disease who do not have overt symptoms.

Diagnosis

Diagnosis of celiac disease can be challenging. If a professional is unfamiliar with the protean manifestations of this disease, it is not considered in the differential diagnosis. Symptoms of the disease overlap with other diseases. Symptom complexes of interintestinal and extraintestinal origin vary in nature and intensity.

Subjects with symptoms or at high risk for celiac disease should undergo laboratory screening. Serologic testing by using anti-tissue transglutaminase (tTG) IgA antibody assay is necessary. A positive result should be confirmed by histological examination; therefore, endoscopy with small-bowel biopsy is considered the “gold standard” for the diagnosis.

It is important to realize that a negative tTG test does not exclude the possibility of the disease later in life in those who have the genetic markers (HLA DQ2 or/and DQ8), which are present in 95% of the patients with celiac disease. In these individuals, celiac disease can manifest at any period of their lives.

Prevention and Treatment

The exact pathomechanism of the disease is still undetermined, and except for the elimination of gluten, there is no known method of prevention. Individuals whose family members have celiac disease have higher lifelong risk (8%–10%). Early detection can alleviate suffering and severe intestinal damage. A lifelong elimination of gluten from the diet is the only available treatment at this time. Foods containing wheat, rye, and barley must be eliminated from the diet. Food labels should be scrutinized for “hidden” sources of gluten. Symptoms may disappear a few weeks after a gluten-free diet is begun, but the complete healing of the lining can take years. Some individuals may remain symptom free even if small amounts of gluten are present in their diets. However, symptom free does not equate to disease free. The damage to the intestine can continue undetected.

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