Photo Quiz - September 2019

A 73/M, from Thanjavur, Tamil Nadu, had a history of erythematous patchy rash with papulonodular lesions for the last 3 years for which he had received multiple short courses of oral prednisolone over 3 years with pulse methylprednisolone therapy given at another center the previous year. Lesions resolved mildly with therapy only to recur later. He was a known diabetic (poorly controlled with OHA + Insulin) for 10 years.

He now presented with worsening of skin lesions with ulcerations and nodular eruptions over extremities associated with fever and chills since one week. On examination, he had reduced superficial sensations over both hands and feet with more impairment over left L3-L5 dermatomal distribution. Other systemic examination was unremarkable.

Investigations showed haemoglobin of 8.3g/dl, platelets-9,83,000/μl ,TLC-29,000/μl (N- 72 L-23 M- 5). Peripheral smear - neutrophilic leukocytosis with toxic granulations with thrombocytosis and giant platelets. HbA1c:7.2 , ESR- 140 , CRP- 143. HIV ELISA –negative. Blood cultures after 96 hours showed no growth. There was no response to IV meropenem and clindamycin. ANA/ANCA/anti MPO Ab and other vasculitis workup was negative.

What is your diagnosis? View Answer

Answer

He underwent a skin biopsy of tissue from nodular skin lesions (see figure).

On Lepra staining -numerous AFB seen singly and in clumps with BI: 6+ and MI: 65%. On histopathology multiple foci of acute inflammation with neutrophils, histiocytes and macrophages, giant cells . AFB lepra stain showed numerous beaded AFB in globi within the macrophages which were changes consistent with ENL.

He was treated for multibacillary leprosy with daily rifampicin, dapsone and clarithromycin. Erythema nodosum leprosum was treated with clofazimine 100mg TDS, prednisone 70 mg OD and thalidomide 100mg BD.

Appearance after 2 weeks

For erythema nodosum leprosum, along with anti-inflammatory agents, rapidly acting disease modifying agents like steroids and thalidomide should be used initially. They should be supported with high dose clofazimine which takes about 4-6 weeks to become effective and has to be continued for 3-4 months. The WHO 2018 guidelines mention criteria for diagnosis and therapy for PBL and MBL. Resistance to front line agents for leprosy mainly for rifampicin, dapsone is emerging. It is difficult to test for drug resistance without PCR based techniques which are not available freely. Hence if resistance to either of the front line drugs is suspected, second line therapy should be commenced with ofloxacin or minocycline with clarithromycin. Post exposure chemoprophylaxis is important for close contacts: single dose rifampicin 600mg has been shown to be effective.

References

  1. WHO 2018 leprosy guidelines
  2. Costa PD et al. Erythema Nodosum Leprosum: Update and challenges on the treatment of a neglected condition. Acta tropica. 2018 Jul 1;183:134-41

Case provided by: Dr Pruthu Dhekane (ID Fellow, Apollo Hospitals, Chennai)