Genetic Conditions Flashcards
What is haemochromatosis
Iron storage disorder that results in excessive total body iron and deposition in tissues.
What type of mutation is haemochromatosis
Autosomal recessive
Which gene is the majority of cases affected in
Human haemochromatosis protein on chromosome 6
Symptoms of haemochromatosis
Chronic tiredness, joint pain, pigmentation, hair loss, erectile dysfunction, amenorrhoea, cognitive symptoms
What age does haemochromatosis present
After the age of 40 when the iron overload becomes symptomatic
What does haemochromatosis present later in females
Due to menstruation acting to regularly elimate iron from the body
Main diagnostic method for haemochromatosis
Serum ferritin level
What test is used to differentiate between haemochromatosis and other causes of high ferritin
Transferrin saturation which is high
What does a liver biopsy with Perl’s stain show
Used to establish the iron concentration in the parenchymal cells
What does an MRI picture show in haemochromatosis
More detailed picture of liver deposits of iron, it can also be used to look at iron deposits in the heart
Complications of haemochromatosis
T1DM, liver cirrhosis, iron deposits in pituitary and gonads, cardiomyopathy, hepatocellular carcinoma, hypothyroidism, chondocalcinosis/ pseudogout
Management of Haemochromatosis
Venesection, monitoring serum ferritin, avoid alcohol, genetic counselling, monitoring and treatment of complications
What is the role of venesection in haemochromatosis
Weekly protcol of removing blood to decrease total iron
What is the gene abnormality in alpha 1 antitrypsin deficiency
Protease inhibitor called alpha 1 antitrypsin on chromosome 14
What type of genetic condition is alpha 1 antitrypsin deficiency
Autosomal recessive
What are the two main organs affected in alpha 1 antitrypsin deficiency
Liver and lungs
What age does liver cirrhosis occur in alpha 1 antitrypsin deficiency
after 50 years old
What age does emphysema and bronchiectasis occur in alpha 1 antitrypsin deficiency
After 30 years old
What happens in the liver in alpha 1 antitrypsin deficiency
The mutant protein gets trapped in the liver and builds up causing liver damage, which progresses to cirrhosis
How is alpha 1 antitrypsin deficiency diagnosed
Low serum alpha 1-antitrypsin, liver biopsy, genetic testing and high resolution Ct thorax
Management of alpha 1 antitrypsin deficiency
Stop smoking, symptomatic management, Organ transplant, monitoring complications
What is Wilson’s disease
Excessive accumulation of copper in the body and tissues
What is the genetic inheritance of Wilson’s disease
Autosomal recessive
Features of Wilson’s disease
Hepatic problems (40%), neurological problems (50%) and psychiatric problems (10%)
How does Wilson’s disease affect the liver
Copper deposition in the liver causes chronic hepatitis and eventually liver cirrhosis.
Diagnosis of Wilsons
Serum caeruloplasmin which is low. and liver biopsy, 24 hour urine copper assay
Treatment of Wilsons
Copper chelation - penicillamine and trientene
