Sarcoidosis
Sarcoidosis is uncommon in pregnancy, affecting 0.05% of all pregnancies in the United Kingdom. It is a multisystem non-caseating granulomatous disorder of unknown aetiology. Chest symptoms include breathlessness and cough, but the patient is often asymptomatic.
The commonest feature is bilateral hilar lymphadenopathy seen on chest radiography or lung computed tomography (CT). There may be extensive pulmonary infiltration progressing to fibrosis. Although there may be no obvious infiltration in the lung fields, the lung parenchyma is usually involved and diagnosis is made by high- resolution CT, bronchoalveolar lavage, and transbronchial biopsy. Lung function may be affected causing an obstructive or restrictive pattern and the transfer factor (diffusing capacity) is reduced. This measurement is not affected by pregnancy and can be used to monitor disease activity. Serum levels of angiotensin-converting enzyme may be altered in normal pregnancy and cannot therefore be used to help diagnosis or monitor disease activity as in the nonpregnant patient.Extrapulmonary manifestations of sarcoidosis include erythema nodosum (which may also occur as an isolated finding in pregnancy without evidence of an underlying associated cause), anterior uveitis, hypercalcaemia, abnormal liver function tests, arthropathy, fever, and central nervous system involvement.
Sarcoidosis may be unaffected or improved by pregnancy. Those with active disease may have resolution of their X- ray changes during pregnancy and there is a tendency for sarcoidosis to relapse in the puerperium. Any improvement that is seen antenatally may be due to the increased levels of endogenous cortisol present in pregnancy.
Sarcoidosis often resolves spontaneously, but indications for steroid treatment include extrapulmonary, especially central nervous system disease, and functional respiratory impairment. Steroids should be continued or started in pregnancy if clinically indicated. Women receiving maintenance steroids should receive ‘stress-dose’ steroids in labour and delivery if they are taking more than 7.5 mg daily of prednisolone. Care should be taken with supplemental vitamin D, which may precipitate hypercalcaemia in patients with sarcoidosis.