Sarcoidosis

Question 1

Sarcoidosis is a multisystem disorder of unknown aetiology characterised by non-caseating granulomas. It is more common in young adults and in people of African descent.

What are the clinical features of sarcoidosis?

Answer 1

• Acute → erythema nodosum, bilateral hilar lymphadenopathy, swinging fever, polyarthralgia
• Insidious → dyspnoea, non-productive cough, malaise, weight loss
• Skin → lupus pernio
• Hypercalcaemia → macrophages inside the granulomas cause an increased conversion of vitamin D to its active form (1,25-dihydroxycholecalciferol)

Two spikes in incidence, in young adulthood and again around age 60. Typical MCQ exam patient is 20-40 y/o black woman presenting w/ dry cough and SoB. They may have nodules ontheir shins suggesting erythema nodosum.

Question 2

What are symptoms affecting each particular system for sarcoidosis?

Answer 2

• Lungs → mediastinal lymphadenopathy, pulm fibrosis + nodules
• Systemic → fever, fatigue, weight loss
• Liver → liver nodules, cirrhosis, cholestasis
• Eyes → uveitis, conjunctivitis, optic neuritis
• Skin → erythema nodosum, lupus pernio, granulomas
• Heart → bundle branch block, heart block, myocardial muscle involvement
• Kidneys → kidneys, nephrocalcinosis, interstitial nephritis
• CNS → nodules, pituitary involvement, encephalopathy
• PNS → facial nerve palsy, mononeuritis multiplex
• Bones → arthralgia, arthritis, myopathy

These are in order of most common to least common (top to bottom)

Question 3

What is Lofgren’s syndrome?

Answer 3

There is a specific presentation of sarcoidosis, triad:

• Erythema nodosum
• Bilateral hilar lymphadenopathy
• Polyarthralgia

Question 4

How is sarcoidosis investigated?

Answer 4

• diagnosis largely clinical
• ACE levels 60% sensitivity + 70% specificity
  
  • not reliable in diagnosis but role in monitoring
• routine bloods may show hypercalcaemia + raised ESR
• CXR may show:
  
  • stage 0 = normal
  • stage 1 = bilateral hilar lymphadenopathy
  • stage 2 = BHL + interstitial infiltrates
  • stage 3 = diffuse interstitial infiltrates only
  • stage 4 = diffuse fibrosis
• spirometry may show restrictive defect
• tissue biopsy shows non-caseating granulomas

Question 5

What is the gold standard for confirming diagnosis of sarcoidosis?

Answer 5

• Histology from biopsy
• Done by bronchoscopy w/ USS guided biopsy of mediastinal lymph nodes
• Histology shows non-caseating granulomas + epithelioid cells

Question 6

No treatment is considered as first line in patients with no or mild symptoms as the condition often resolves spontaneously.

What is the management of sarcoidosis?

Answer 6

Steroids indicated if:

• Pts w/ CXR stage 2 or 3 disease who have moderate-severe or progressive symptoms. Pts w/ asymptomatic + stable stage 2 or 3 disease who have only mildly abnormal lung function do not require treatment
• Hypercalcaemia
• Eye, heart or neuro involvement

Give bisphosphonates for bone protection too. Second line includes methotrexate and azathioprine. Lung transplant in severe disease.