Management of Type 1 Lepra Reactions
Type 1 lepra reactions (reversal reactions) require immediate initiation of oral corticosteroids at 1-2 mg/kg/day prednisolone, with treatment duration extending beyond the traditional 12-week course to prevent silent nerve damage and recurrence. 1, 2, 3
Immediate Assessment and Treatment Initiation
Severity Stratification:
- Mild reactions (no neuritis): Start prednisolone 1 mg/kg/day orally 4
- Severe reactions or any neuritis present: Start prednisolone 2 mg/kg/day orally and strongly consider hospitalization 1, 4
- Rapidly progressive or severe neuritis: Consider IV methylprednisolone 1g daily for 3 days followed by oral prednisolone 2
The FDA label explicitly states that if Type 1 reactions are severe or neuritis is present, large doses of steroids should always be used and the patient should be hospitalized 1. This is critical because Type 1 reactions result from enhanced delayed hypersensitivity causing swelling of existing skin and nerve lesions, which can rapidly progress to irreversible nerve damage 1, 5.
Treatment Duration and Tapering
The traditional 12-week WHO recommendation is insufficient. 3
Recommended approach:
- Continue prednisolone at initial dose until clinical improvement (typically 4-8 weeks) 2, 3
- Begin taper only after complete resolution of acute inflammatory signs 3
- Total treatment duration should be at least 16-20 weeks to prevent recurrence 2, 3
- Taper slowly over 4-6 weeks once improvement achieved 2
Evidence shows that 50% of patients require additional prednisolone despite 16 weeks of treatment, indicating that even this extended duration may be inadequate for some patients 2. Earlier data conclusively demonstrate that discontinuing prednisolone early leads to silent nerve damage that may not be clinically apparent until irreversible disability occurs 3.
Continuation of Anti-Leprosy Treatment
Continue multi-drug therapy (MDT) throughout the reaction. 1
The FDA label is explicit that anti-leprosy treatment should be continued during Type 1 reactions, as the reaction represents an immunological response to reduced antigenic load rather than treatment failure 1. Stopping MDT risks disease progression and does not improve the reaction 1.
Adjunctive Measures
For severe neuritis with nerve trunk swelling:
- Analgesics for pain control 1
- Consider surgical decompression of swollen nerve trunks in consultation with specialists 1
- Contact specialized leprosy centers (historically USPHS Carville) for complex cases 1
Monitoring and Prevention of Complications
Critical monitoring parameters:
- Weekly assessment of nerve function (sensory and motor testing) during first month 2, 4
- Monthly nerve function assessment during months 2-6 2, 4
- Neurophysiological studies (nerve conduction) at baseline, 1 week, 1 month, and 6 months for objective documentation 4
The evidence demonstrates that deterioration in sensory function can occur between day 29 and day 113 of treatment, even with adequate corticosteroid therapy 2. This underscores the need for prolonged monitoring beyond the acute treatment phase.
Special Considerations for High-Dose IV Methylprednisolone
While IV methylprednisolone 1g daily for 3 days did not show significant differences in overall clinical improvement compared to oral prednisolone alone, patients receiving methylprednisolone were less likely to experience deterioration in sensory function during the later treatment period (days 29-113) 2. Consider this approach for:
- Rapidly progressive neuritis 2
- Multiple nerve involvement 2
- Patients with borderline leprosy at high risk for severe reactions 5
Common Pitfalls to Avoid
Never use short-course steroids (less than 12 weeks) for Type 1 reactions. This is the most common error and leads to recurrence and silent nerve damage 3. The historical data clearly show that 12 weeks is inadequate, yet this remains the WHO recommendation 3.
Do not delay steroid initiation while awaiting specialist consultation. Type 1 reactions cause nerve damage through acute inflammation, and delays in treatment result in irreversible disability 1, 5. Start treatment immediately and consult specialists concurrently.
Do not stop MDT during reactions. This is explicitly contraindicated and worsens outcomes 1.
Do not assume clinical improvement means nerve function is preserved. Silent nerve damage can occur even when skin lesions improve 3. Objective nerve function testing is mandatory throughout treatment 2, 4.
Distinguishing Type 1 from Type 2 Reactions
Type 1 reactions occur in borderline or tuberculoid leprosy, often soon after chemotherapy initiation, with swelling of existing lesions and neuritis 1. Type 2 reactions (ENL) occur mainly in lepromatous patients with fever, tender erythematous nodules, and systemic features 1. This distinction is critical because Type 2 reactions may require different management including thalidomide (available through specialized centers) 1, 6.