Question 136#

A 72-year-old female is admitted with diarrhoea to the acute medical unit. A sigmoidoscopy is performed which shows multiple white plaques adhered to the gastrointestinal mucosa.

What is the most likely diagnosis?

A. Crohn's disease

Correct Answer D: 

Clostridium difficile:
Clostridium difficile is a Gram positive rod often encountered in hospital practice. It produces an exotoxin which causes intestinal damage leading to a syndrome called pseudomembranous colitis. Clostridium difficile develops when the normal gut flora are suppressed by broad-spectrum antibiotics. Clindamycin is historically associated with causing Clostridium difficile but the aetiology has evolved significantly over the past 10 years. Second and third generation cephalosporins are now the leading cause of Clostridium difficile.

Features:

• Diarrhoea
• Abdominal pain
• A raised white blood cell count is characteristic
• If severe toxic megacolon may develop

Diagnosis is made by detecting Clostridium difficile toxin (CDT) in the stool.

Management:

• First-line therapy is oral metronidazole for 10-14 days
• If severe or not responding to metronidazole then oral vancomycin may be used
• For life-threatening infections a combination of oral vancomycin and intravenous metronidazole should be used

Question 137#

You are reviewing a 31-year-old man in the liver clinic. He is currently on interferon-alpha treatment.

What is the best way to assess his response to treatment?

A. Alanine transaminase level

Correct Answer 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: 

• The risk of transmission during a needle stick injury is about 2%
• The vertical transmission rate from mother to child is about 6%
• Breast feeding is not contraindicated in mothers with hepatitis C
• The risk of transmitting the virus during sexual intercourse is probably less than 5%

Features:

• After exposure to the hepatitis C virus less than 20% of patients develop an acute hepatitis Complications
• Chronic infection (80-85%) - only 15-20% of patients will clear the virus after an acute infection and hence the majority will develop chronic hepatitis C
• Cirrhosis (20-30% of those with chronic disease)
• Hepatocellular cancer
• Cryoglobulinaemia

Management of chronic infection:

• Currently a combination of pegylated interferon-alpha and ribavirin are used
• Up to 55% of patients successfully clear the virus, with success rates of around 80% for some strains
• The aim of treatment is sustained virological response (SVR), defined as undetectable serum HCV RNA six months after the end of therapy

Complications of treatment:

• Ribavirin - side-effects: haemolytic anaemia, cough. Women should not become pregnant within 6 months of stopping ribavirin as it is teratogenic
• Interferon alpha - side-effects: flu-like symptoms, depression, fatigue, leukopenia, thrombocytopenia

Question 138#

What percentage of patients with chronic hepatitis C will develop liver cirrhosis over a 20-30 year period?

A. 5-10%

Correct Answer C: Liver cirrhosis will develop in around 20-30% of patients over 20-30 years.

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: 

• The risk of transmission during a needle stick injury is about 2%
• The vertical transmission rate from mother to child is about 6%
• Breast feeding is not contraindicated in mothers with hepatitis C
• The risk of transmitting the virus during sexual intercourse is probably less than 5%

Features:

• After exposure to the hepatitis C virus less than 20% of patients develop an acute hepatitis Complications
• Chronic infection (80-85%) - only 15-20% of patients will clear the virus after an acute infection and hence the majority will develop chronic hepatitis C
• Cirrhosis (20-30% of those with chronic disease)
• Hepatocellular cancer
• Cryoglobulinaemia

Management of chronic infection:

• Currently a combination of pegylated interferon-alpha and ribavirin are used
• Up to 55% of patients successfully clear the virus, with success rates of around 80% for some strains
• The aim of treatment is sustained virological response (SVR), defined as undetectable serum HCV RNA six months after the end of therapy

Complications of treatment:

• Ribavirin - side-effects: haemolytic anaemia, cough. Women should not become pregnant within 6 months of stopping ribavirin as it is teratogenic
• Interferon alpha - side-effects: flu-like symptoms, depression, fatigue, leukopenia, thrombocytopenia

Question 139#

Which one of the following is most strongly associated with coeliac disease? 

A. HLA A5

Correct Answer B: 

Coeliac disease:

 Coeliac disease is caused by sensitivity to the protein gluten. Repeated exposure leads to villous atrophy which in turn causes malabsorption. Conditions associated with coeliac disease include dermatitis herpetiformis (a vesicular, pruritic skin eruption) and autoimmune disorders (type 1 diabetes mellitus and autoimmune hepatitis).

It is strongly associated with HLA-DQ2 (95% of patients) and HLA-B8 (80%) as well as HLA-DR3 and HLA-DR7 In 2009 NICE issued guidelines on the investigation of coeliac disease.

They suggest that the following patients should be screened for coeliac disease:

Complications:

• Anaemia: iron, folate and vitamin B12 deficiency (folate deficiency is more common than vitamin B12 deficiency in coeliac disease)
• Hyposplenism
• Osteoporosis
• Lactose intolerance
• Enteropathy-associated T-cell lymphoma of small intestine
• Subfertility, unfavourable pregnancy outcomes
• Rare: oesophageal cancer, other malignancies

Question 140#

Which one of the following statements regarding hepatitis B and pregnancy is correct? 

A. Without intervention the vertical transmission rate is around 3%

Correct Answer D: Without intervention the vertical transmission rate is around 20%, which increases to 90% if the woman is positive for HBeAg. 

Hepatitis B and pregnancy:

Basics:

• All pregnant women are offered screening for hepatitis B
• Babies born to mothers who are chronically infected with hepatitis B or to mothers who've had acute hepatitis B during pregnancy should receive a complete course of vaccination + hepatitis B immunoglobulin
• Studies are currently evaluating the role of oral antiviral treatment (e.g. Lamivudine) in the latter part of pregnancy
• There is little evidence to suggest caesarean section reduces vertical transmission rates
• Hepatitis B cannot be transmitted via breastfeeding (in contrast to HIV)