ANSWER 57
The likely diagnosis is sarcoidosis. The age is typical and sarcoidosis is more common in
those of African-Caribbean origin. The chest X-ray shows bilateral hilar lymphadenopathy.
The blood results show a slightly raised calcium level which is related to vitamin D sensi-
tivity in sarcoidosis where the granulomas hydroxylate 25-hydroxycholecalciferol to 1,25-
dihydroxycholecalciferol. The ESR is raised and some of the liver enzymes are around the
upper limit of normal. The skin lesions at the hairline and the nostrils are typical sites for
sarcoid skin problems. The eye trouble 6 weeks earlier might also have been a manifesta-
tion of sarcoidosis, which can cause both anterior and posterior uveitis.
An alternative diagnosis which might explain the findings is tuberculosis. Tuberculosis can
also cause hypercalcaemia although this is much less common than in sarcoid. Tumours,
especially lymphoma, might give this X-ray appearance but would not explain the other
findings. The arthralgia (pains with no evidence of acute inflammation or deformity on
examination) can occur in sarcoid or tuberculosis but again they are commoner in sarcoid.
The ESR is non-specific. Arthralgia without deformity in an African-Caribbean man raises
the possibility of systemic lupus erythematosus (SLE), but this would be much commoner
in women and would not cause bilateral hilar lymphadenopathy.
He is likely to have had BCG (bacille Calmette–Guèrin) vaccination at school at around the age
of 12 years, giving a degree of protection against tuberculosis. A tuberculin test should be pos-
itive after BCG, strongly positive in most cases of tuberculosis and negative in 80 per cent of
cases of sarcoidosis. The serum level of angiotensin-converting enzyme would be raised in
over 80 per cent of cases of sarcoidosis but often in tuberculosis also; the granuloma cells
secrete this enzyme. A computed tomography (CT) scan of the chest will confirm the extent of
the lymphadenopathy and show whether there is any involvement of the lung parenchyma.
Histology of affected tissue would confirm the clinical diagnosis. This might be obtained by a
skin biopsy of one of the lesions. A bronchial or transbronchial lung biopsy at fibreoptic bron-
choscopy would be another means of obtaining diagnostic histology. In patients with a cough
and sarcoidosis the bronchial mucosa itself often looks abnormal, and biopsy will provide the
diagnosis. Lung function tests and electrocardiogram (ECG) should be performed as a baseline
if the diagnosis is confirmed.
Steroid treatment would not be necessary for the hilar lymphadenopathy alone, but would
be indicated for the hypercalcaemia and possibly for the systemic symptoms.
- Sarcoidosis is commoner in African-Caribbeans.
- Typical sites for skin lesions are around the nose and the hairline.
- Sarcoidosis is a systemic disease and can affect most parts of the body.