What is the recommended treatment for leprosy?

Treatment of Leprosy

The recommended treatment for leprosy is multidrug therapy (MDT) consisting of rifampicin, dapsone, and clofazimine, with duration determined by leprosy classification as either paucibacillary (6 months) or multibacillary (12 months). 1, 2

Classification and Treatment Regimens

Leprosy is classified into two main types for treatment purposes:

1. Paucibacillary (PB) Leprosy:

   • Duration: 6 months
   • Regimen:
     • Rifampicin: 600 mg once monthly (supervised)
     • Dapsone: 100 mg daily (self-administered)

2. Multibacillary (MB) Leprosy:

   • Duration: 12 months
   • Regimen:
     • Rifampicin: 600 mg once monthly (supervised)
     • Clofazimine: 300 mg once monthly (supervised) and 50 mg daily (self-administered)
     • Dapsone: 100 mg daily (self-administered)

Pediatric Dosing

For children, doses are adjusted by weight:

• Clofazimine: 2-3 mg/kg/day (maximum 100 mg daily) 3
• Dapsone: Pediatric dosing should be correspondingly smaller than adult doses, typically starting at lower doses 2
• Rifampicin: Adjusted by weight

Evidence Supporting MDT

The World Health Organization (WHO) recommends MDT as the standard treatment for leprosy. This recommendation is supported by multiple studies showing high efficacy and acceptable safety profiles 1, 4, 5.

A network meta-analysis of 60 controlled clinical trials including 9,256 patients confirmed that MDT is effective for treating leprosy, particularly multibacillary leprosy 1. The uniform MDT regimen has shown low relapse rates (2.6-4.5 per 1000 patient-years) in clinical trials 4.

Key Considerations in Management

Monitoring for Adverse Effects

1. Dapsone:

   • Screen for G6PD deficiency before starting treatment
   • Monitor for hemolytic anemia, methemoglobinemia, and peripheral neuropathy
   • Common side effects include gastrointestinal disturbances 3

2. Clofazimine:

   • Monitor for skin pigmentation (reversible but may take time to resolve)
   • Perform monthly ECGs when possible, especially when combined with other QTc-prolonging agents
   • Counsel patients about skin discoloration 3

3. Rifampicin:

   • Monitor liver function
   • Be aware of potential drug interactions

Leprosy Reactions

Patients should be monitored for and educated about leprosy reactions, which can occur during or after treatment:

1. Type 1 (Reversal) Reaction:

   • Characterized by increased inflammation in existing lesions
   • May require corticosteroid treatment

2. Type 2 (Erythema Nodosum Leprosum) Reaction:

   • Clofazimine (P score=0.9141) and dapsone+rifampicin (P score=0.8785) are effective for treating type 2 leprosy reactions 1
   • Thalidomide may be used in severe cases (with appropriate precautions)

Special Populations

HIV Co-infection

In HIV/AIDS-associated leprosy, systemic antileishmanial therapy is recommended, particularly in persons who are moderately to severely immunosuppressed, as they may be at increased risk for suboptimal therapeutic responses, post-treatment relapses, and cutaneous, mucosal, or visceral dissemination 3.

Pregnancy

Dapsone can be used during pregnancy. However, clofazimine should be used with caution, and rifampicin requires careful consideration of risks and benefits.

Treatment Compliance and Follow-up

• Compliance to MDT is crucial for successful treatment and prevention of drug resistance
• Clinical trials have reported high compliance rates (99%) with MDT regimens 5
• Regular follow-up during and after treatment is essential to monitor for:
  • Treatment response
  • Drug adverse effects
  • Leprosy reactions
  • Relapse

Pitfalls to Avoid

1. Monotherapy: Single-drug regimens are not effective enough to treat leprosy and can lead to drug resistance 1, 6
2. Premature discontinuation: Incomplete treatment can lead to relapse and drug resistance
3. Inadequate monitoring: Failure to monitor for adverse effects and leprosy reactions
4. Missing drug interactions: Particularly with rifampicin, which induces cytochrome P450 enzymes
5. Overlooking neurological assessment: Regular nerve function assessment is essential to prevent disability

MDT has transformed leprosy from a dreaded, incurable disease to a curable condition with excellent outcomes when diagnosed early and treated appropriately.