Rare occurrence of lepra type 1 reaction in pure neuritic le
Type 1 reaction in pure neuritic leprosy usually occurs in the form of neuritis. The development of new skin lesion during reaction is rare. Clinicians should be aware about occurrence of type 1 reaction in pure neuritic leprosy.

A 36-year-old lady presented with ulcer over anterolateral aspect of left foot for a duration of 8 months. She was diagnosed as leprosy from other center and was started on WHO MB-MDT blister pack. She was under fifth blister pack at the time of presentation to our center. She had history of decreased sensation over bilateral hands and feet but there was no history of any cutaneous lesions of leprosy.

Clinical examination showed thickened and non-tender peripheral nerves (ulnar, radio cutaneous, and lateral popliteal) with complete loss of sensation to temperature (hot/cold), touch, and pain over bilateral hands and feet as per WHO testing sites. There was hypothenar atrophy on right hand and mobile clawing of little finger on left hand. No cutaneous lesions suggestive of leprosy were noted.

Slit skin smear was negative. Nerve conduction study revealed asymmetrical sensory-motor axonal polyneuropathy involving peripheral nerves of upper limbs and symmetrical sensory involvement on nerves of lower limbs. The diagnosis of pure neuritic Hansen's disease with grade II disability of bilateral hands and left foot and grade I disability of right foot was made, and the patient was continued with WHO MB-MDT. For trophic ulcer, conventional dressing was done daily with ointment mupirocin followed by application of paraffin mesh (Jelonettm Smith & Nephew) and non-adherent dressing. The ulcer was healed completely in 4 weeks.

Three months later, the patient developed acute onset swelling of bilateral legs associated with tingling sensation disturbing daily activities. There was presence of pitting edema over bilateral feet extending till distal one-third of legs. Similarly, erythematous edematous area was noticed over left cheek.

The clinical diagnosis of lepra type 1 reaction was confirmed by examination of biopsy specimen taken from two sites, face and leg, which showed edematous dermis with perivascular, periadnexal, and interstitial lymphohistiocytic infiltrate along with few epithelioid histiocytes. The infiltrates were encroaching the arrector pili muscles and destructing nerve bundles. Stain for acid-fast bacilli (lepra) was negative.

Erythema and edema over left cheek and edema on bilateral legs improved considerably after 2 weeks of starting oral prednisolone 40 mg following which dose of corticosteroid was tapered slowly. The pedal edema subsided and the erythematous plaque over the left cheek resolved in 8 weeks, and after 30 weeks of treatment with tapering dose of oral corticosteroid, steroid was stopped. The patient completed 24 blister pack of WHO MB-MDT.

Source: https://onlinelibrary.wiley.com/doi/10.1002/ccr3.4324?af=R