What is the initial treatment for a patient presenting with pseudogout (calcium pyrophosphate deposition disease)?

Initial Treatment for Pseudogout (Calcium Pyrophosphate Deposition Disease)

For acute pseudogout, initiate treatment with NSAIDs, corticosteroids (oral, intra-articular, or intramuscular), or colchicine as first-line monotherapy, with the specific choice determined by the number of joints involved, contraindications, and patient comorbidities. 1

Treatment Selection Algorithm

For Monoarticular or Oligoarticular Attacks (1-3 joints):

• Intra-articular corticosteroid injection is particularly useful and safe for monoarticular or oligoarticular microcrystalline synovitis 1
• NSAIDs at full anti-inflammatory doses (e.g., diclofenac 150 mg/day for 3 days, then 75 mg/day for 3 days, or naproxen at full dosing) are effective first-line options 1
• Oral colchicine can be used, though evidence is more limited than for gout 1

For Polyarticular Attacks:

• Oral corticosteroids, parenteral corticosteroids, or ACTH are useful alternative treatment modalities for patients with polyarticular attacks 1
• Intramuscular triamcinolone acetonide 60 mg is safe, well-tolerated, and effective, with all patients in one prospective study achieving at least 50% improvement 2
• Parenteral corticosteroids (betamethasone 7 mg IM or methylprednisolone 125 mg IV) provide faster pain control than NSAIDs, with significant improvement by day 1 (NNT=3) 1

For Patients with NSAID Contraindications:

• Corticosteroids become the primary treatment option when NSAIDs are contraindicated 1, 2
• In one study, 12 of 14 pseudogout patients had NSAID contraindications and all responded well to intramuscular triamcinolone acetonide 60 mg 2
• ACTH 40-80 units given intravenously, intramuscularly, or subcutaneously three times resolved all acute attacks in an average of 4.2 days 1

Specific Dosing Recommendations

Corticosteroids:

• Intramuscular triamcinolone acetonide 60 mg (may require second injection on day 1-2 if inadequate response) 2
• Intra-articular injection for 1-2 affected joints (dose varies by joint size) 1
• Betamethasone 7 mg IM or methylprednisolone 125 mg IV as single injection 1

NSAIDs:

• Full anti-inflammatory doses until symptoms resolve 1
• Diclofenac 150 mg daily for 3 days, then 75 mg daily for 3 days 1

Colchicine:

• Standard dosing for acute attacks (though less evidence than for gout) 1
• Treatment with colchicine and naproxen combination has been reported effective 3

Expected Response Timeline

• Major clinical improvement typically occurs by day 3-4 in most patients (11 of 14 patients in one study) 2
• Corticosteroid injections provide faster pain relief than NSAIDs, with significant improvement by day 1 1
• Some patients may require up to 10-14 days for complete resolution 2

Prophylaxis Considerations

• Low-dose colchicine 0.6 mg twice daily may be efficacious as prophylactic therapy for recurrent acute attacks, reducing attack frequency from 3.2 per year to 1.0 per year in one study 1
• The evidence for prophylactic NSAIDs is less clear and requires investigation 1
• Carefully consider potential side effects before initiating prophylactic therapy 1

Critical Safety Points

• Corticosteroid treatment is generally well-tolerated, with only minor adverse effects reported (profuse sweating, hot flushes) 1
• ACTH may cause mild hypokalemia, hyperglycemia, fluid retention, and rebound arthritis, but these are easily controlled 1
• No significant toxicities were observed with intramuscular triamcinolone acetonide in prospective study 2

Common Pitfalls

• Distinguish pseudogout from septic arthritis through arthrocentesis and crystal analysis - this is essential as treatment approaches differ dramatically 3
• Consider pseudogout in post-operative settings, particularly after parathyroidectomy or arthroplasty 4, 3
• Check for associated metabolic abnormalities (hypocalcemia, hypomagnesemia) that may trigger pseudogout flares 3