Effective amelioration of the Lucio phenomenon with adjuvant tofacitinib therapy in a patient with dual infection of Mycobacterium leprae and Mycobacterium lepromatosis: a case report from India

Introduction. The Lucio phenomenon (LP) is a characteristic reaction pattern seen in patients with diffuse lepromatous leprosy (DLL). Dual infection with Mycobacterium leprae and Mycobacterium lepromatosis in DLL has been confirmed from other endemic countries but not previously documented from India. Conventionally, LP is treated with a high dose of systemic glucocorticoid (GC) and anti-leprosy treatment (ALT). Here we report a case of leprosy lymphadenitis at initial presentation in a patient with LP and DLL due to dual infection with M. leprae and M. lepromatosis who responded favourably to tofacitinib as adjuvant to ALT and systemic GC therapy. Case report. A 20- to 30-year-old man presented with swelling over the bilateral inguinal region, pus-filled skin lesions with multiple ulcers, fever and joint pain. Post-hospitalization investigations showed the presence of anaemia, leukocytosis, and elevated acute and chronic inflammatory markers. Skin and lymph node biopsies were suggestive of LP and leprosy lymphadenitis. The presence of M. leprae and M. lepromatosis was confirmed by PCR followed by DNA sequencing of PCR amplicons from tissue. Despite anti-leprosy treatment, oral GC and thalidomide therapy, the patient continued to develop new lesions. One month after the commencement of adjuvant tofacitinib, the patient showed excellent clinical improvement with healing of all existing lesions and cessation of new LP lesions. Conclusion. Our case confirms the presence of dual infection with M. leprae and lepromatosis in India. Lymph node involvement as an initial presentation of DLL should be considered in endemic areas. Tofacitinib may be a promising new adjuvant therapy for recalcitrant lepra reactions.


Introduction
The Lucio phenomenon (LP) is a characteristic reaction pattern seen in patients with diffuse lepromatous leprosy (DLL) characterized by ulceronecrotic lesions.Infection with Mycobacterium lepromatosis has been reported from many endemic countries as a cause of DLL and LP.Dual infection of Mycobacterium leprae and M. lepromatosis has been confirmed from other endemic countries but not previously documented from India.Though involvement of lymph nodes in leprosy and the lepra reaction is not uncommon, generalized lymphadenopathy as an initial presentation is not routine.Conventionally, LP is treated with a high dose of systemic glucocorticoid (GC) and anti-leprosy treatment (ALT).Here we report a case of leprosy lymphadenitis at initial presentation in a patient with LP and DLL due to dual infection with M. leprae and M. lepromatosis who responded favourably to tofacitinib as adjuvant to ALT and systemic GC therapy.Studies have shown that the pathogenesis of the type 2 lepra reaction involves increased Th2 cytokine expression (e.g.IL4, IL5, IL6), with recent evidence of Th17 cell involvement.Tofacitinib is a reversible inhibitor of the enzyme Janus kinase (JAK) that effectively diminishes the intracellular signal transduction of the above-mentioned cytokines.

Case presentation
A 20-to 30-year-old man presented with swelling over the bilateral inguinal region, pus-filled skin lesions with multiple ulcers, fever and joint pain.The asymptomatic inguinal swelling had been present for the last 5 months for which he was on anti-tubercular drugs.He started to develop skin lesions which were associated with fever and joint pain 2 months before his presentation.On examination the patient had multiple well-defined punched out ulcers of varying sizes with violaceous margins and necrotic haemorrhagic slough, present predominantly over both extremities (Fig. 1a).
Multiple tender and enlarged lymph nodes were present in bilateral inguinal, axillary and cervical regions (largest measuring 3×2 cm).There were no signs of ear lobe infiltration, nerve thickening or sensory loss.Initial clinical differentials of pityriasis lichenoides et varioliformis acuta, LP and pyoderma gangrenosum were considered.Post-hospitalization investigations showed the presence of anaemia, leucocytosis, and elevated acute and chronic inflammatory markers (Table 1).
Punch biopsy of the skin from margins of ulcers demonstrated infiltrates of foamy histiocytes and lymphocytes following neurovascular bundles, admixed with neutrophils and signs of vasculitis (Fig. 2a-c).Fite-Faraco staining revealed fragmented and granular acid fast bacilli (Fig. 2d).Biopsy of inguinal lymph nodes showed infiltration of foamy histiocytes and presence of acid fast bacilli (Fig. 2e, f).
The presence of M. leprae in lymph node biopsies and M. lepromatosis in both lymph node and skin biopsies were confirmed by standard PCR (Table 1) [1,2], followed by DNA sequencing of PCR amplicons.
Based on the above clinical and laboratory findings, a final diagnosis of DLL with LP due to dual infection with M. leprae and M. lepromatosis was established and the patient was started on ALT (rifampicin, minocycline, ofloxacin and clofazimine) with oral prednisolone (1 mg kg -1 ) and thalidomide (200 mg twice day).One month after starting this therapy, the patient did not show any improvement in skin lesions or systemic complaints.Laboratory markers of inflammation remained high.Given the presence of a severe neutrophilic response, adalimumab was administered subcutaneously (40 mg) as an adjuvant therapy after discussing and gaining consent for its off-label use with the patient.The patient reported mild improvements after the first dose of adalimumab but presented with increased skin lesions and systemic complaints (fever and joint pain) after the second dose (Fig. 1b).In view of the worsening clinical condition and persistent high laboratory markers of inflammation, off-label use of oral tofacitinib was discussed with the patient and consent for its use was given.One month after administration of tofacitinib the patient reported marked healing of the skin ulceration and cessation of new lesions (Fig. 1c).Laboratory evaluation revealed leukocytosis returning to a normal range and other inflammatory markers showing reducing trends.The patient was continued on ALT and oral steroids throughout this treatment period; oral thalidomide therapy was discontinued after commencement of tofacitinib.At the time of writing of this report, the patient is in remission of LP and on regular ALT.ALT, anti-leprosy treatment.

Discussion
M. lepromatosis has been recognized as causing DLL and severe LP from endemic countries in South America and Southeast Asia [3,4].Dual infection with M. leprae and M. lepromatosis has been confirmed in around 14 % cases where species identification was performed using genomic techniques [5].Our patient had a clinical presentation of DLL and LP with dual infection from both species.These findings corroborate presentations from other endemic countries and represent the first confirmation of dual infection in India.Involvement of lymph nodes in patients with leprosy, particularly at the lepromatous pole, is well established.Our case is unique in its presentation where generalized lymphadenitis was the initial disease presentation.In the absence of characteristic infiltrated skin lesions associated with leprosy, it was misdiagnosed as tuberculous lymphadenitis.It is thus pertinent to keep this presentation in mind by clinicians as it can be confused with other causes of generalized lymphadenopathies and diagnosis may be delayed, particularly in patients with DLL.The LP involves a severe necrotizing skin reaction in cases of DLL with systemic manifestations and can be fatal if left untreated.Systemic GC along with ALT remains the mainstay of treatment for LP.For non-responding cases or patients with a persistent reaction, alternative therapies such as thalidomide and pentoxifylline have been utilized along with GC.Recently, biological therapy (e.g.TNF-α inhibitors) has been successfully used in the management of recalcitrant lepra reactions.[6] Our patient showed no improvement in skin lesions or systemic complaints despite use of GC, thalidomide and a TNF-α inhibitor.Studies on the pathogenesis of the type 2 lepra reaction show increase expression of Th2 cytokines such as IL4, IL5 and IL6 [7].Recently, the role of Th17 cells has also been established in the pathogenesis of LP [8].Tofacitinib is a JAK inhibitor that inhibits the intracellular signal transduction of pro-inflammatory cytokines.It is being increasingly utilized in various autoinflammatory conditions having a similar Th17 cytokine profile.With this rationale we decided to utilize it in our patient.The patient showed an excellent clinical response to tofacitinib as adjuvant to GC, which was further corroborated by improvement in laboratory markers of inflammation.Our case is unique as the first reported case of dual infection with M. leprae and M. lepromatosis from India, lymph node involvement as a presenting feature and excellent response to tofacitinib.
Limitations include that this is a report of a single case.Tofacitinib was used as adjuvant to GC and ALT, and thus not all clinical improvement may not be attributed to tofacitinib alone.Larger case series or randomized trials are needed before tofacitinib can be firmly established in the management of lepra reactions.

Table 1 .
Sequential details of laboratory, radiological and microbiological investigations of case

2 months post-therapy (adjuvant adalimumab 2 dose of 40 mg, 15 days apart) 3 month post-therapy (adjuvant tofacitinib 5 mg twice day)
[5]. tuberculosis not detected using culture and cartridge-based amplification test.•Presence of M. leprae was confirmed in skin tissue using PCR.M. leprae specific repetitive element (RLEP)-forward 5′-TGCATGTCATGGCCTTGAGG-3′ and RLEP-reverse 5′-CACCGATACCAGCGGCAGAA-3′ and product size 129 bp.• Presence of M. lepromatosis was confirmed in skin and lymph node tissues via heminested PCR using protocol developed by Han and Quintanilla in 2015[5].First round of PCR was done with primers AFBO (5′-GCGTGCTTAACACATGCAAGTC, common to all mycobacterial species) and MLER4 (5′-CCACAAGACATGCGCCTTGAAG, specific for M. leprae); product size is 171 bp.It was diluted 100-fold and further amplified with three separate second rounds of PCR using MLER4 as the anchoring primer to pair with primer LPMF2 (5′-GTCTCTTAATACTTAAACCTATTAA, specific for M. lepromatosis); amplicon of 142 bp in size.It was further confirmed by DNA sequencing of PCR product, which showed 100 % similarity with M. lepromatosis.Imaging studiesChest X-ray: no abnormality detected.Ultrasonography of lymph node: multiple enlarged lymph nodes in bilateral inguinal, axilla and cervical region.Largest measuring 25×9 mm in right inguinal region, 19×6 mm in left inguinal region, 23×11 mm in right axilla, 21×12 mm in left axilla and 20×11 mm in left level 1B.All lymph nodes show altered echotexture with internal areas of necrosis.
This study would be a valuable contribution to the existing literature.The reviewers have highlighted minor concerns with the work presented.Please ensure that you address their comments.Reviewers and I have reviewed your manuscript and as you can see from the largely positive comments below, there are a few suggestions on how your manuscript can be improved.The case is very interesting and would be of great interest of clinicians in the field; however it would be beneficial to describe tofacitinib and its potential role in managing these infections briefly in the Introduction as suggested; and validation of the diagnostic processes.Additionally, there are a few grammatical errors that would benefit from a thorough proof-read.Please try and address these and I look forward to receiving your revised manuscript.The authors have described a case with possible mixed infection of M. leprae and M. lepromatosis based on the PCR results: targeting M. leprae specific repetitive sequence RLEP, while for M. lepromatosis, and nested PCR approach was used targeting single copy gene in M. lepromatosis.The authors have cited a reference Ahuja et al 2018, which was later on retracted and authors have not mentioned this in the manuscript despite being aware of this.Major comments are as follows: (i) The authors have not performed sequencing of the PCR product after heminested PCR to confirm the presence of M. lepromatosis, in addition to M. leprae specific amplcons of RLEP.Mere amplification shouldn't be considered as a confirmation of presence of M. lepromatosis.Authors should justify why the sequencing couldn't be done, as some of the authors on this work have performed sequencing routinely for drug resistance related studies and are familiar with the technology and analysis part.(ii)The authors have not used additional genomic targets which are known to be specific for M. lepromatosis such as hemN gene (later re-annotated as hemW) or the multi-copy genomic targets described for M. lepromatosis genome in subsequent studies etc in recent publications.This should be explained, as these are very important findings and should be confirmed.(iii)Therearetypographicalerrorswhich need to be carefully corrected, such as line 114: "collaborate" to be replaced by "corroborate"? (iv) Auto-capitalization after full stop in Line 135 (M.Leprae and M. Lepromatosis) should be corrected as "M.leprae and M. lepromatosis" throughout the manuscript.(v)Line109:severLPfrom endemic countries.spellingtobecorrectedtoseverePlease rate the quality of the presentation and structure of the manuscript SatisfactoryTo what extent are the conclusions supported by the data?Partially supportDo you have any concerns of possible image manipulation, plagiarism or any other unethical practices?NoIs there a potential financial or other conflict of interest between yourself and the author(s)?NoIf this manuscript involves human and/or animal work, have the subjects been treated in an ethical manner and the authors complied with the appropriate guidelines?Yes Reviewer 1 recommendation and comments https://doi.org/10.1099/acmi.0.000460.v1.4 © 2022 Serrano-Coll H.This is an open access peer review report distributed under the terms of the Creative Commons Attribution License.