A. Ferritin – Explanation

The above patient has symptoms consistent with haemochromatosis. The excessive thirst is
secondary to untreated diabetes mellitus. Diabetes mellitus itself would not normally cause reduced
libido or arthralgia.

Haemochromatosis: features
Haemochromatosis is an autosomal recessive disorder of iron absorption and metabolism resulting
in iron accumulation. It is caused by inheritance of mutations in the HFE gene on both copies of
chromosome 6*. It is often asymptomatic in early disease and initial symptoms often non-specific
e.g. lethargy and arthralgia

Epidemiology

• 1 in 10 people of European descent carry a mutation genes affecting iron metabolism, mainly HFE
• prevalence in people of European descent = 1 in 200

Presenting features

• early symptoms include fatigue, erectile dysfunction and arthralgia (often of the hands)
• ‘bronze’ skin pigmentation
• diabetes mellitus
• liver: stigmata of chronic liver disease, hepatomegaly, cirrhosis, hepatocellular deposition)
• cardiac failure (2nd to dilated cardiomyopathy)
• hypogonadism (2nd to cirrhosis and pituitary dysfunction – hypogonadotrophic hypogonadism)
• arthritis (especially of the hands)

Questions have previously been asked regarding which features are reversible with treatment:

*there are rare cases of families with classic features of genetic haemochromatosis but no mutation
in the HFE gene
**whilst elevated liver function tests and hepatomegaly may be reversible, cirrhosis is not