A 35-year-old woman presents with a 12-month history of unintentional weight loss, fatigue, bloating, diarrhoea, mouth ulcers and an itchy bumpy rash on the extensors of her elbows. She has a past medical history of type 1 diabetes mellitus. Her full blood count shows low haemoglobin, her iron studies show low ferritin and her haematinics screen shows she is folate deficient.

What is the most likely diagnosis?

Options:
explanation: This is not the correct answer. While gastroenteritis can present with similar symptoms such as abdominal discomfort, bloating, and diarrhoea, it is more likely to present for a shorter duration and with symptoms such as nausea, vomiting and fever. However, given the association with diabetes type 1 and dermatitis herpetiform, systemic symptoms and clinical features of malabsorption, the more likely diagnosis is coeliac disease. A stool culture can be taken to rule out infectious causes. The gold standard diagnosis to confirm coeliac disease would be an oesophago-gastroduodenoscopy with biopsy. Other tests to support the diagnosis include serological tests that would most likely show anti-TTG antibodies and anti-endomysial antibodies, and blood tests (FBC may show anaemia, Iron, B12 and folate levels may be low and so forth).
name: Gastroenteritis
label: e
answer: no
explanation: This is not the correct answer. Irritable bowel syndrome is characterised by similar symptoms such as abdominal pain, bloating, and altered bowel habits. However, given the association with diabetes type 1 and dermatitis herpetiform, systemic symptoms and clinical features of malabsorption, the more likely diagnosis is coeliac disease. The gold standard diagnosis to confirm coeliac disease would be an esophagogastroduodenoscopy with biopsy. Other tests to support the diagnosis include serological tests that would most likely show anti-TTG antibodies and anti-endomysial antibodies, and blood tests (FBC may show anaemia, Iron, B12 and folate levels may be low and so forth).
name: Irritable bowel syndrome
label: b
answer: no
explanation: This is the correct answer. Coeliac disease is an autoimmune condition where the body has a T cell-mediated inflammatory response to gluten, leading to small bowel injury and subsequent malabsorption. This causes gastrointestinal symptoms such as abdominal pain, bloating, diarrhoea, nausea and vomiting, and steatorrhoea in severe disease. It can also cause systemic symptoms such as fatigue and weight loss. Dermatological manifestations include dermatitis herpetiformis which presents with pruritic papulovesicular lesions over the buttocks and extensor surfaces of the arms, legs, and trunk, as seen in this patient where she has an itchy bumpy rash on the extensors of her elbows. Due to malabsorption, clinical features of vitamin and mineral deficiencies may be present as well such as bruising due to vitamin K deficiency, or as seen in this patient, low ferritin and folate levels. Lastly, coeliac disease is associated with a positive family history, the HLA-DQ2 allele, and other autoimmune diseases such as type 1 diabetes mellitus which is present in this patient.
name: Coeliac disease
label: a
answer: yes
explanation: This is not the correct answer. Food intolerance can present with similar symptoms such as abdominal discomfort, bloating, and diarrhoea. However, given the association with diabetes type 1 and dermatitis herpetiform, systemic symptoms and clinical features of malabsorption, the more likely diagnosis is coeliac disease. The gold standard diagnosis to confirm coeliac disease would be an oesophago-gastroduodenoscopy with biopsy. Other tests to support the diagnosis include serological tests that would most likely show anti-TTG antibodies and anti-endomysial antibodies, and blood tests (FBC may show anaemia, Iron, B12 and folate levels may be low and so forth).
name: Food intolerance
label: d
answer: no
explanation: This is not the correct answer. Crohn's disease and ulcerative colitis are forms of inflammatory bowel disease and may present with similar symptoms such as abdominal pain, diarrhoea, and weight loss. The gold standard diagnosis to confirm coeliac disease would be an oesophagogastroduodenoscopy with biopsy. Other tests to support the diagnosis include serological tests that would most likely show anti-TTG antibodies and anti-endomysial antibodies, and blood tests (FBC may show anaemia, Iron, B12 and folate levels may be low and so forth).
name: Inflammatory bowel disease
label: c
answer: no

Correct answer: a