Celiac Disease

Malabsorption can cause:

• The changes in the bowel make it less able to absorb nutrients, minerals and the fat-soluble vitamins A, D, E, and K • The inability to absorb carbohydrates and fats may cause weight loss (or failure to thrive/stunted growth in children) and fatigue or lack of energy. • Anaemia may develop in several ways: iron malabsorption may cause iron deficiency anaemia, and folic acid and vitamin B12 - malabsorption may give rise to megaloblastic anaemia. • Calcium and vitamin D malabsorption (and compensatory secondary hyperparathyroidism) may cause osteopenia (decreased mineral content of the bone) or osteoporosis (bone weakening and risk of fragility fractures). • A small proportion have abnormal coagulation due to vitamin K deficiency and are slightly at risk for abnormal bleeding. • Coeliac disease is also associated with bacterial overgrowth of the small intestine, which can worsen malabsorption or cause malabsorption despite adherence to treatment.

Pathophysiology:

• Upon exposure to gliadin, and specifically to three peptides found in prolamins, the enzyme tissue transglutaminase (tTG) modifies the protein, and the immune system cross-reacts with the small-bowel tissue, causing an inflammatory reaction. • Tissue transglutaminase tTG modifies gluten peptides in two ways: deamidation or transamidation. That leads to a truncating of the villi lining the small intestine (called villous atrophy). This interferes with the absorption of nutrients, because the intestinal villi are responsible for absorption.

Diagnosis:

Its important that when the patient is taking the tests that he or she is NOT on a gluten free diet Serology: - Antiendomysial antibodies of the immunoglobulin A (IgA) type can detect coeliac disease with a sensitivity and specificity of 90% and 99%, respectively. - Serology for anti-tTG antibodies was initially reported to have a higher sensitivity (99%) and specificity (>90%) for identifying coeliac disease. Positive blood test is still followed by an endoscopy/gastroscopy and biopsy. Tissue biopsy is still considered the gold standard in the diagnosis of coeliac disease.

Classification of Celiac disease:

Marsh classification

Genetics

Patient with Celial disease has either: 1. HLA-DQ2 allele (90-95%) or 2. HLA-DQ8 allele ( 5-10%). However, about 20-40% of people without coeliac disease have also inherited either of these alleles. Thus HLA not suffiecient to develop Celiac disease

Symptoms

SYMPTOMS • Severe coeliac disease leads to the characteristic symptoms of: pale, loose and greasy stool (steatorrhoea), and weight loss or failure to gain weight (in young children). People with milder coeliac disease may have symptoms that are much more subtle and occur in other organs than the bowel itself. It is also possible to have coeliac disease without any symptoms whatsoever. Many adults with subtle disease only have fatigue or anaemia gastrointestinal syptoms: Abdominal pain and cramping, bloatedness with abdominal distension (thought to be due to fermentative production of bowel gas) and mouth ulcers may be present. As the bowel becomes more damaged, a degree of lactose intolerance may develop.

Symptoms:

chronic diarrhoea, failure to thrive (in children)due to malabsorption, and fatigue, but these may be absent, and symptoms in other organ systems have been described.

Classification

CLASIFICATION • classic- serology+, gastrointestinal symptoms, villous atrophy • non typical- serology +, extraintestinal symptoms , villous atrophy • latent- serology+, without symptoms, villous atrophy • potential- serology +, without symptoms and without villous atrophy

Definition:

Coeliac disease is an autoimmune disorder of the small intestine that occurs in genetically predisposed people of all ages from middle infancy onward.

Cause:

Coeliac disease is caused by a reaction to gliadin, a prolamin (gluten protein) found in wheat, and similar proteins found in the crops of the tribe Triticeae (which includes other common grains such as barley and rye).

Celiac disease might be confused with

Frequently, the symptoms are ascribed to irritable bowel syndrome (IBS), only later to be recognised as coeliac disease; a small proportion of patients with symptoms of IBS have underlying coeliac disease, and screening for coeliac disease is recommended for those with IBS symptoms.( 3,6 % patients).

Treatment

Gluten free diet

Celiac disease has been linked to numerous of conditions:

IgA deficiency • Dermatitis herpetiformis • Growth failure and/or pubertal delay in later childhood • Recurrent miscarriage and unexplained infertility. • Hyposplenism • Abnormal liver function tests other disorders: disorders: diabetes mellitus type 1 (10%), autoimmune thyroiditis (4-8%), autoimmune hepatitis (8%) and microscopic colitis ( lymphocytic)- 2-40%