26th February 2025

Sarcoidosis

Clinical features of sarcoidosis

Sarcoidosis is a multisystem inflammatory disorder characterised by non-caseating granulomas on histology.

Acute sarcoidosis (Löfgren’s syndrome) classically presents with a triad of erythema nodosum, fever and bilateral hilar lymphadenopathy. These features are not always all present, and polyarthritis is also commonly seen. It is generally self-limiting, and lymphadenopathy tends to resolve within 1 year.

Chronic sarcoid is more variable and can affect almost any organ system. Lung disease is the most common manifestation, either as bi-hilar lymphadenopathy or, at later stages, as pulmonary fibrosis. The most classic skin involvement is lupus pernio, a violaceous plaque or nodules that affects the nose, cheeks and ears. Cardiac and neurological involvement has a poor prognosis of up to 25% mortality. Granulomas can be found anywhere, including liver, kidneys, and GI tract; however, symptoms are generally caused by release of mediators, not the granulomas themselves.

Investigations in sarcoidosis

Blood tests can reveal hypercalcaemia or elevated serum ACE. ACE is produced by granulomas, so can be used to monitor disease activity as a marker of granuloma burden.

Chest X-ray may show bi-hilar lymphadenopathy or pulmonary fibrosis. Findings are generally graded by the Scadding stages:

Table 6 Scadding staging system for sarcoidosis

Sarcoid can mimic many other diseases, including TB and malignancies, so tissue diagnosis is generally required. This can be obtained from the most easily accessible lesion, often using techniques such as EBUS.

Management of sarcoidosis

Acute sarcoidosis is generally self-limiting and does not require intervention.

Management of chronic sarcoidosis varies from case to case, depending on presentation and organ involvement. A global summary, which should be adequate for MRCP purposes, is that glucocorticoids are indicated where there is risk of significant or progressive organ involvement, demonstrated by the mnemonic PUNCH:

• Progressive lung involvement
• Uveitis
• Neurological involvement
• Cardiac involvement
• Hypercalcaemia

References

• Chauhan A, Jandial A, Mishra K, Sandal R. Acute arthritis, skin rash and Lofgren’s syndrome. BMJ Case Reports. 2021 Jun;14(6):e239239
• Grunewald J, Grutters JC, Arkema EV, Saketkoo LA, Moller DR, Müller-Quernheim J. Sarcoidosis. Nature Reviews Disease Primers. 2019 Jul 4;5(1)
• Clunie GPR, Wilkinson N, Nikiphorou E, Deepak Jadon. Oxford handbook of rheumatology. Oxford: Oxford University Press; 2018
• Gerke AK. Treatment of Sarcoidosis: A Multidisciplinary Approach. Frontiers in Immunology [Internet]. 2020 Nov 19 [cited 2022 May 8];11. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7732561/