What is the initial management for a patient suspected to have pseudogout (Calcium Pyrophosphate Deposition Disease, CPPD)?

Management of Suspected Pseudogout (CPPD)

For patients with suspected pseudogout (calcium pyrophosphate deposition disease), first-line treatment should be NSAIDs, oral corticosteroids, or intra-articular corticosteroid injections based on the number of joints involved and patient comorbidities.

Diagnosis Confirmation

Before initiating treatment, confirm the diagnosis by:

• Joint aspiration and synovial fluid analysis to identify calcium pyrophosphate crystals (weakly positive birefringent rhomboid-shaped crystals under polarized microscopy)
• Radiographic imaging to detect chondrocalcinosis (linear stippled calcifications in cartilage)

Acute Attack Management

First-line options (based on joint involvement):

1. For monoarticular or oligoarticular attacks:

   • Intra-articular corticosteroid injection (preferred if 1-2 joints affected) 1
     • Dose depends on joint size
     • Provides rapid relief with minimal systemic effects

2. For polyarticular attacks or when joint injection is not feasible:

   • Oral NSAIDs (if no contraindications) 1

     • Full anti-inflammatory doses until attack resolves
     • Examples: naproxen, diclofenac, indomethacin
     • Avoid in patients with renal impairment, history of GI bleeding, or cardiovascular disease

   • Oral corticosteroids 1

     • Prednisone 30-35 mg daily for 3-5 days
     • Option for patients with contraindications to NSAIDs
     • Taper not necessary for short courses

   • Intramuscular/intravenous corticosteroids 1

     • Methylprednisolone 0.5-2.0 mg/kg IV or IM
     • Triamcinolone acetonide 60 mg IM
     • Good option for NPO patients or those with multiple joint involvement

3. For patients unable to take oral medications (NPO):

   • Parenteral corticosteroids (IV/IM) 1
   • Subcutaneous ACTH 25-40 IU with repeat doses as needed 1

Second-line options:

• Colchicine 1

  • Low-dose regimen: 0.6 mg twice daily
  • Less effective than in gout but can be considered
  • Reduce dose in renal impairment
  • Avoid with strong P-glycoprotein/CYP3A4 inhibitors

• IL-1 inhibitors (anakinra) 2

  • For refractory cases not responding to conventional therapy
  • Off-label use
  • Contraindicated in active infection

Special Considerations

For patients with renal impairment:

• Avoid NSAIDs and high-dose colchicine 1
• Prefer corticosteroids (oral, intra-articular, or parenteral) 1
• Note that pseudogout is more common in patients with chronic kidney disease 3

For elderly patients:

• Higher prevalence of CPPD (15.8% in dialysis patients >60 years) 3
• Consider comorbidities when selecting therapy
• Prefer intra-articular steroids when feasible to minimize systemic effects

For recurrent attacks:

• Consider prophylactic therapy with low-dose colchicine (0.6 mg once or twice daily) 1
• A small uncontrolled trial showed reduction in attack frequency from 3.2 to 1 per year 1

Addressing Underlying Causes

Evaluate for metabolic conditions associated with CPPD:

• Hyperparathyroidism
• Hemochromatosis
• Hypomagnesemia (especially in younger patients) 4
• Hypophosphatasia
• Hypothyroidism

Follow-up Management

• Treat the underlying metabolic disorder if identified
• For patients with concurrent osteoarthritis and CPPD, follow standard OA management guidelines 1
• For chronic CPP crystal inflammatory arthritis not responding to conventional therapy, consider:
  • Low-dose methotrexate (5-10 mg/week) 1
  • Hydroxychloroquine 1

Common Pitfalls to Avoid

1. Misdiagnosing pseudogout as gout or septic arthritis
2. Failing to aspirate the joint to confirm diagnosis
3. Not investigating for underlying metabolic disorders
4. Using high-dose colchicine regimens (can cause severe toxicity)
5. Overlooking CPPD in atypical locations (temporomandibular joint, great toe)

Remember that unlike gout, there are currently no disease-modifying therapies that reduce calcium pyrophosphate crystal deposition 2. Treatment focuses on managing inflammation and reducing symptoms during acute attacks.