What specialist and diagnostic tests are recommended for a sarcoidosis (Sarcoid) workup?

Sarcoidosis Workup and Specialist Referral

Patients with suspected sarcoidosis should be referred to a pulmonologist for initial evaluation and management, with additional specialist referrals based on organ involvement. 1, 2

Initial Diagnostic Tests

• Chest Imaging: Start with chest X-ray and high-resolution CT scan to detect bilateral hilar adenopathy, perilymphatic nodules, and parenchymal infiltrates which are highly characteristic of pulmonary sarcoidosis 1, 3
• Laboratory Tests:
  • Serum calcium (strong recommendation) to screen for abnormal calcium metabolism 1
  • Serum creatinine to screen for renal involvement 1
  • Serum alkaline phosphatase to screen for hepatic involvement 1
  • Consider measuring both 25-OH and 1,25-OH vitamin D levels if vitamin D assessment is needed 1
• Cardiac Screening:
  • Baseline ECG to screen for cardiac involvement 1
  • Consider cardiac MRI if cardiac involvement is suspected; if unavailable, dedicated PET is preferred over echocardiography 1
• Biopsy: Tissue sampling for histopathologic confirmation of noncaseating granulomas, typically from the most accessible involved site 1
  • Note: In patients with highly characteristic presentations (e.g., Löfgren's syndrome, lupus pernio), lymph node sampling may be deferred 1

Specialist Referrals Based on Organ Involvement

• Pulmonologist: Primary specialist for initial evaluation and management due to frequent lung involvement (90% of cases) 4, 5
• Cardiologist: For patients with suspected cardiac involvement based on ECG abnormalities, symptoms (exertional chest pain, syncope), or imaging findings 1
• Ophthalmologist: For patients with ocular symptoms or signs (uveitis, optic neuritis, scleritis, retinitis) 1, 2
• Dermatologist: For patients with skin manifestations (lupus pernio, erythema nodosum, maculopapular lesions) 1, 2
• Neurologist: For patients with neurological symptoms (cranial nerve palsies, especially facial nerve) 1, 2
• Nephrologist: For patients with evidence of renal involvement (elevated creatinine, hypercalciuria, nephrolithiasis) 1
• Hepatologist: For patients with significant liver abnormalities (elevated alkaline phosphatase >3x normal) 1
• Rheumatologist: For patients with significant joint involvement or when considering immunosuppressive therapies 5, 2

Additional Testing Based on Suspected Organ Involvement

• Pulmonary Function Tests: To assess lung function impairment and monitor disease progression 4, 3
• Bronchoscopy with BAL and transbronchial biopsy: For tissue diagnosis and to exclude other causes 1
• Echocardiography: If pulmonary hypertension is suspected based on symptoms or exam findings 1
• Right heart catheterization: If echocardiogram suggests pulmonary hypertension 1
• PET scan: Useful for detecting multiorgan involvement and guiding biopsy sites 1, 6

Diagnostic Pitfalls to Avoid

• Failure to exclude alternative diagnoses: Always consider other granulomatous diseases including infections (tuberculosis, fungal), berylliosis, hypersensitivity pneumonitis, and vasculitis 1
• Relying solely on ACE levels: While elevated ACE can support diagnosis, it lacks sensitivity and specificity 1
• Missing cardiac involvement: Cardiac sarcoidosis can be fatal and may require specific imaging beyond routine echocardiography 1
• Overlooking drug-induced sarcoid-like reactions: Consider medication review, especially immunotherapeutics and anti-TNF agents 1
• Inadequate follow-up: Patients who don't undergo biopsy require close clinical monitoring 1

Algorithm for Specialist Referral

1. Initial referral to pulmonologist for comprehensive evaluation 4, 5
2. Additional specialist referrals based on:
   • Organ-specific symptoms or signs
   • Abnormal laboratory findings
   • Imaging evidence of extrapulmonary involvement
   • Disease severity and treatment requirements 1, 2
3. Consider multidisciplinary sarcoidosis clinic if available, especially for complex cases with multiorgan involvement 4, 2