Which one of the following is least likely to cause malabsorption?
Correct Answer E:
Malabsorption: Malabsorption is characterized by diarrhoea, steatorrhoea and weight loss. Causes may be broadly divided into intestinal (e.g. villous atrophy), pancreatic (deficiency of pancreatic enzyme production or secretion) and biliary (deficiency of bile-salts needed for emulsification of fats).
Intestinal causes of malabsorption:
Pancreatic causes of malabsorption:
Biliary causes of malabsorption:
Other causes:
A 42-year-old woman is investigated for lethargy and diarrhoea. Investigations reveal positive antiendomysial antibodies.
Each of the following food stuffs should be avoided, except:
Correct Answer C:
Coeliac disease: management:
The management of coeliac disease involves a gluten-free diet. Gluten containing cereals include:
Some notable foods which are gluten-free include:
*Whisky is made using malted barley. Proteins such as gluten are however removed during the distillation process making it safe to drink for patients with coeliac disease.
**Some patients with coeliac disease appear able to tolerate oats.
Which one of the following statements best describes the prevention and treatment of hepatitis C?
Hepatitis C: Hepatitis C is likely to become a significant public health problem in the UK in the next decade. It is thought around 200,000 people are chronically infected with the virus. At risk groups include intravenous drug users and patients who received a blood transfusion prior to 1991 (e.g. haemophiliacs).
Transmission:
Features:
Complications:
Management of chronic infection:
Complications of treatment:
The most common type of inherited colorectal cancer:
Colorectal cancer: genetics:
It is currently thought there are three types of colon cancer:
Studies have shown that sporadic colon cancer may be due to a series of genetic mutations. For example, more than half of colon cancers show allelic loss of the APC gene. It is believed a further series of gene abnormalities e.g. activation of the K-ras oncogene, deletion of p53 and DCC tumour suppressor genes lead to invasive carcinoma.
HNPCC, an autosomal dominant condition, is the most common form of inherited colon cancer. Around 90% of patients develop cancers, often of the proximal colon, which are usually poorly differentiated and highly aggressive. Currently seven mutations have been identified, which affect genes involved in DNA mismatch repair leading to micro-satellite instability. The most common genes involved are:
The Amsterdam criteria are sometimes used to aid diagnosis:
FAP is a rare autosomal dominant condition which leads to the formation of hundreds of polyps by the age of 30- 40 years. Patients inevitably develop carcinoma. It is due to a mutation in a tumour suppressor gene called adenomatous polyposis coli gene (APC), located on chromosome 5. Genetic testing can be done by analyzing DNA from a patients white blood cells. Patients generally have a total colectomy with ileo-anal pouch formation in their twenties.
Patients with FAP are also at risk from duodenal tumours. A variant of FAP called Gardner's syndrome can also feature osteomas of the skull and mandible, retinal pigmentation, thyroid carcinoma and epidermoid cysts on the skin.
Which one of the following statements regarding hepatitis C is correct?
Correct Answer B: