INTERNATIONAL JOURNAL OF LEPROSY Volume 64, Number 3Printed in the U.S.A.

(ISSN 0148-91 6X)

Multibacillary Nerve Histology in Clinically DiagnosedBorderline Tuberculoid Leprosy Patients'

Gigi Jasmine Ebenezer, Sujai Suneetha, Renu Mohandas, and S. Arunthathi 2

The past two decades have seen drasticchanges in the time schedule for the treat-ment of leprosy patients, resulting in short-term anti leprosy courses. The World HealthOrganization (WHO) recommends a stan-dard multidrug therapy (MDT) consistingof 600 mg of rifampin given once a monthfor 6 months, plus dapsone 100 mg dailyfor 6 months for paucibacillary (13 13) pa-tients and a regimen consisting of rif .ampin600 mg once a month, dapsone 100 mgdaily and clofazimine 300 mg once a monthand 50 mg daily given over a period of atleast 2 years for multibacillary (MB) pa-tients ("). MDT coverage has been exten-sively and successfully used in many areas,hut it is obvious that due to these two defi-nite therapeutic regimens the responsibilityfor categorizing a patient into one or theother is increased. This may be a crucialfactor in the ultimate goal of the eliminationof leprosy as a public health problem. Clas-sification of leprosy based on the clinicalfeatures of characteristic skin lesions stillremains the essence of this categorization ( 4 .

'"). The disparity between the clinical andhistological classification across the spec-trum of leprosy is known to exist ").Striking differences in the histopathologicalfeatures of leprosy lesions in the skin andcutaneous nerves have been reported in afew studies ( 7 .' 2 ).

This study was done to find out whethersuch disparity exists in the nerves of chili-

' Received for publication on 5 December 1995; ac-cepted for publication in revised form on 22 April1996.

= C. J. Ebenezer, M.B.B.S., NI.D., Ag. I lead, De-partment of Ilistopathology and Experimental Pathol-ogy; S. Suncetha, M.B.B.S., D.C.P., Ag. Head, Depart-ment of Immunology and Clinical Pathology; R. Mo-handas, M.B.B.S., Medical Officer; S. Arunthathi,M.B.B.S., M.D., Head, Branch of Medicine, Schieffe-lin Leprosy Research and Training Center, Karigiri632 106, North Arcot District, Tamil Nadu, India.

cally diagnosed borderline tuberculoid (BT)skin lesions. Its relevance to the present-day diagnostic and therapeutic trends inleprosy is also discussed in this paper.

MATERIALS AND METHODSLeprosy patients attending the outpatient

department of the Schieffelin Leprosy Re-search and Training Center in Karigiri,South India, were clinically classified ac-cording to the classification described byRidley and Jopling ( 1 "). Among those clini-cally diagnosed as BT, only those who hadone or more enlarged cutaneous nerves andwere willing to undergo biopsy of the skinand nerve were selected for the study. Thecharacteristic features of skin lesions thatclinically classified a patient as belongingto the BT group included single or multiple,dry, hypopigmented, Ilat or raised patchesof any size with ill-defined or well-definedmargins. Modalities of sensation were lostto varying degrees in these patches. Skinsmears for acid-fast bacilli (A113) weredone by the slit and scrape method from sixroutine sites in all patients and selected sitesin some patients.

A sliver of nerve from a thickened pe-ripheral cutaneous nerve was biopsied ineach of these patients. The most commonlybiopsied nerve was the radial cutaneous,followed by the musculocutaneous, ulnarcutaneous and other cutaneous nerves. Anelliptical piece of skin was biopsied eitherfrom an active skin lesion overlying thethickened nerve or from a similar patch sit-uated away from such a nerve. Biopsieswere taken under local anesthesia by thestandard Khanolkar technique (''). The skinbiopsies were fixed in Formol-Zenker andthe nerves in 10% buffered formalin. Serialsections of 5-mm thickness were stainedwith hematoxylin and eosin (H&E) for rou-tine study and a modified Fite-Faraco stainfor AFB ( 5 ).

3 I 1

312 ^ International Journal of Leprosy^ 1996

THE TABLE. Hi.slOpa/h0/ogy of skinand nerve in 21 clinically diagnosed 137'patients.

I listopathological classification'

Skin^ Nerve

BT^ Ind.Ind.^ 131.Ind.^ PNTInd.^ NSLBT^ BLInd.^ BLBT^ BTNSI^ PNT13L^ BLNSI^ NSLNSI^ NSLBT^ BTBT^ BLBT^ BLBT^ BLNSI^ BLNSI^ NSLBL^ 13LBT^ 13TInd.^ 13LBT^ 13T

= Borderline tuberculoid leprosy; Ind. = inde-terminate leprosy; BL= borderline lepromatous lep-rosy; PNT = perineurial thickening; NSL = no signifi-cant lesion; NSI = nonspecific inflammation.

The skin and nerve lesions were carefullystudied histopathologically and classifiedaccording to the features described by Job( 3) and Ridley ( 9). The histopathologicalclassification of skin and nerve differ inonly some aspects. Caseation is more com-mon in nerve lesions in tuberculoid (TT)leprosy and organisms may be focused inthe areas of necrosis. In BT leprosy thereare no major differences between skin andnerve lesions. In the nerve in borderlinelepromatous (BL) leprosy the lymphocytesare concentrated near the epineurium ratherthan the entire lesion, and macrophages arerelatively few. In lepromatous (LL) leprosythe macrophages are fewer in the nerve le-sions, and bacilli are mainly found inSchwann cells. The bacterial index (BI) ofthe granuloma was assessed for the skin andnerve biopsies separately ( 9 ).

RESULTSOf the clinically diagnosed BT patients,

21 with enlarged cutaneous nerves were

FR;. I. Photomicrograph of skin showing focal ar-eas of epitheloid granulomas admixed with lympho-cytes in BT leprosy (H&E x100).

studied (16 males and 5 females). The dura-tion of the disease ranged from 1 month to10 years (mean 2 years and 2 months).Eighteen of these patients were untreatedand 3 of them had received dapsone mono-therapy, 2 for a period of < 2 months and 1for 3 years' duration. Skin smears were pos-itive for AFB from a selected site in one pa-tient. Skin smears from all other patientswere negative.

Of the 21 clinically diagnosed BT pa-tients, only 9 of the skin and 4 of the nervebiopsies showed the characteristic granulo-matous inflammation of BT histopathology,consisting of poorly organized collectionsof epithelioid cells admixed with lympho-cytes (Fig. 1). Two of the skin and 10 of thenerve biopsies showed 131. histology (Figs.2 and 3). Five skin specimens showed non-specific chronic inflammation. Two nervebiopsies had only perineurial thickeningand four showed no significant lesion (The

_^ .f7

•?41:7 , '

• ••••■dIllom■

!111.1111.1‘'44,X44114111N."41Lime416%._

-440411b,LtIts_isoli - ,^•ileb 4, .•■,%

116%.' Ile Alip ..844‘`t• I* Apa4114114 4:` "AM^mak'^.*41

v. API

64, 3^Ebeneze►; G., et al.: MB Nerve Histology in BT^313

---11_-‘;,--;`;-:-.- -4.'---- ----,•— ---...izti,-,^ srl- J.-. ^- -

..;...: „...4s..„:..4...t..0.: 4 ....„ . _,_ ,,,,,,,..„,,,, - ; .1.- ...4i-S,(-_, 11-7--21.4-..: A - -. :;.-ftIck.; ;,--'''''..; ..--., .1-:;," - - !'"2.‘'e",. '''_.,% ........, ?t: -•:-* ''.; d•Z: ;1* •*. .."':-.'fC ':V-• • . 1%;-:.,,,,:t1-:.........- '.':,...1,i- • it.t.-,...".;-• -...a ",■... -.:4,7_ 7 st az.,:t. rl•-•:...-;,.,>:

,-;;,..._ •;.--,',1-.:!"."-; .:.:-;..A.,....,:=4.":-.:....:...:n".._--1'.,--z:-.,.-1:4--ile;,--.--:,=,,,,,----•-ef--, •N't', "--..- .74•'. •-•:;;;-...`...'"•:, f'',.• • 744: --';':',.:-=%-..-':,,, ;,..,e-',,'"-e.,,:;:: si.y--• r•i ..1.

" .11.4:(:.... i. ', ;':•'-i'•:<.;,C.:4...Sr.

A.: .: ......._:77.;.N.,:,' --.0,-,17:7-F.---:::"!;.=•---...;'ir;,..:. ''",• ..1. .''' ;'"l4-.. ‹

,;417•11,...:. ....,.•.•-.■- :;'.i.:7' Ala if...L.:. '"1-- .e;, f;.• .•= .,,n.;::,; , ,...:"Zr•JE::. 4.'1 t; '":,S1-- -:....;t4'."--•:;•... :!;',::;' .,•";:•::i'.:47trz''''.;•■• -,;-r '''.: .."C'",1•1‘,4M- --", '''''''... '''

Fic. 2. Photomicrograph of a longitudinal sectionof a nerve with granuloma destroying and protrudingthrough the perineurium in 131. leprosy (III &E. x100).

FIG. 3. Photomicrograph showing clump of acid-fast bacilli in a Schwann cell (Fite-Faraco x1000).

Table). The BI of two skin biopsies with BLhistology were 2+ and in 10 of the nervebiopsies varied from 2 to 4+. All othernerve and skin biopsies were negative forAFB.

DISCUSSIONThis study confirms earlier studies de-

scribing the disparity between clinical andhistopathological diagnosis ('' "). Even withthe histopathological examination of bothskin and nerve, 4 of the 21 patients (19%)did not have any evidence of leprosy. Theimportance of the histopathological exami-nation of leprosy lesions in any researchstudy (especially chemotherapeutic trials inPB patients) is clearly brought out here.

Further, this study shows without anydoubt the discordance in histopathologicalappearance of the nerve and skin biopsiesfrom the same patient. A few earlier studiesemphasize this important point ( 7 . ' 2 ). Thepresence of AFB in skin lesions makes thepatient multibacillary and eligible for a

2-year duration of MDT. The absence ofAFB makes him/her paucibacillary, qualify-ing for only 6 months of MDT. In most lep-rosy clinics, diagnosis is based entirelyupon clinical examination, and they are notequipped to do even skin smears. In thisstudy I of the 21 BT patients (clinically di-agnosed as BT and therefore classified asPB) showed AFB during skin-smear exam-ination. On histopathological study of theskin, two patients had AFB in the macro-phages, in dermal nerves and in arrestorpili muscle cells of the skin lesions. Whencutaneous nerve biopsies were performed,10 out of 21 (47.6%) were BL patients withAFB in macrophages and Schwann cells.Should all of these patients with demonstra-ble AFB in the skin/nerve lesions be classi-fied as MB and he given the benefit of a2-year period of MDT?

One reason pointed out for the compara-tively higher relapse rate following MDT inPB leprosy is the possibility of potentialMB patients being misdiagnosed as PB lep-

314^ International Journal of Leprosy^ 1996

rosy and given the shorter MDT regimen( 2.'). The patient who is positive for AFB inskin smears, of course, qualifies for MBMDT. It is imperative to resolve the ques-tion of whether M. leprae confined to a fewscattered macrophages and dermal or cuta-neous nerves makes a patient multibacil-lary, requiring a longer period of therapy.We intend to follow up the 10 PB patientswith AFB in cutaneous nerves and 2 pa-tients with AFB in dermal nerves and an oc-casional macrophage in the skin lesion tofind out the relapse rate among them. Amuch larger number of PB patients with M.leprae-positive nerve lesions, dermal andcutaneous, will have to be studied and care-fully followed up before this question is fi-nally answered.

SUMMARYThe classification of leprosy into multi-

bacillary (MB) and paucibacillary (PB) pa-tients in almost all clinics is entirely depen-dent on clinical examination. In a study of21 patients clinically classified as border-line tuberculoid (BT) and, therefore, be-longing to the PB group, skin smears andskin and nerve biopsies were examined.Four patients did not have any histopatho-logical evidence of leprosy. Skin smearsshowed that 1 patient was positive for acid-fast bacilli (AFB), 2 skin biopsies belongedto the borderline lepromatous (BL) cate-gory and showed AFB in their lesions, andAFB were present in 10 nerve biopsies clas-sified as BL. It is possible that reported re-lapses among PB patients may be in thosepatients with demonstrable AFB in the le-sions, including nerves. A careful follow-upstudy of this particular group of patients af-ter PB multidrug therapy is suggested to re-solve this question.

RESUMENLa clasificacion de los pacientes con lepra, como

multibacilares (MB) o paucibacilares (PM, se hate enla mayorla de los casos sobre la base del examenclinico. En el presente trabajo se hit() el estudio de lalinfa cutanea y de hiopsias de piel y nervios, corre-spondientes a 21 pacientes PI3 clasificados clínica-mente como tuherculoides subpolares (11T). Se encon-tro que cuatro pacientes no tuvieron ninguna evidenciahistológica de la lepra. El examen de la hnfa cutancamostró que on paciente fue positivo para bacilos

resistentes (BAAR), dos hiopsias de piel corre-spondieron a la categoria de lepromatosos subpolares(BL) y mostraron BAAR en sus lesiones, y diet biop-sias de nervios clasificados como BL mostraronBAAR. Es posihle que las recaldas reportadas entre lospacientes PB pudieran ocurrir principalmente en acme-llos pacientes con BAAR demostrables en las lesiones,incluyendo nervios. pant analitar esta posibihdad, sesugiere un estudio de seguimiento coidadoso de estegrupo de pacientes P13, después de concluir la poll-quimioterapia.

RÉSUMÉLa classification de la lepre en patients multibacillaires(MB) et paucibacillaires (P13) depend dans presquetoes les centres de l'examen clinique. Dans une etudede 21 patients chniquement classifies comme border-line tuberculoides (13T) et done appurtenant au groupeBT, des froths cutanes et des biopsies cutanées etnerveuses ont etc examines. Quatre patients n'avaientpas le moindre signe histopathologique de lepre. Lesfrottis cutanes out montre qu'un patient etait positifpour les bacilles acido- resistants (BAR), deux biop-sies cutanées appartenaient a la categoric borderlinelépromateuse (BL) et montraient des BAR dans leerslesions, et des BAR etaient presents dans dix biopsiesde nerfs classifiCes BL. II est possible que les rechutesrapportées parmi les patients PB pourraient correspon-dre ces patients chez lesquels des BAR out etc mis enevidence thins les lesions, y compris les nerfs. On sug-gère one etude soigneusc de suivi de cc groupe parti-culier de patients apres polychimiotherapie pour PBpour resoudre cette question.

Acknowledgment. The authors thank Dr. CharlesK. Job and Dr. P.S.S. Sundar Rao for their commentsand advice toward the preparation of this manuscript.

REFERENCES1. 130A-riA, A. S., KATOCH, K., NARAYANAN, R. 13.,

RAmu, G., MUKHERJEF, A. and L,wANIA, R. K.Clinical and histopathological correlation in theclassification of leprosy. Int. J. Lepr. 61 (1993)433-438.

2. EKAMBARAM, V. and RAo, M. K. Relapse rate inpaucibacillary leprosy patients after multidrugtherapy in North Arcot District. Indian J. Lepr. 63(1991) 34-42.

3. Jon, C. K. Pathology of leprosy. In: "Leinv.v .v."2nd. edn. Hastings, R.C., ed. Edinburgh: ChurchillLivingston, 1994, p. 200.

4. Jon, C. K. and CoAcK0, C.J.G. A simplified 6group classification of leprosy. Lepr. India 54(1981) 14-16.

5. JOB, C. K. and CtiAcKo, C.J.G. A modification ofFite's stain for demonstration of Al. leprae in tis-sue sections. Indian J. Lepr. 58 (1986) 17-18.

64, 3^Ebenezer G., et al.: MB Nerve Histology iii BT^315

6. KliANoi.KAR, V. R. Method of taking biopsy tissuefor histopathological examination. Lepr. Rev. 22(1951) 83-85.

7. Nu.stiN, R., MliNGISTU, G. and RFDDY, B.B. Therole of nerve biopsies in the diagnosis and man-agement of leprosy. Lepr. Rev. 60 (1989) 28-32.

8. RAM, G. Duration of MDT for paucibacillaryleprosy. Indian J. Lepr. 64 (1992) 1-7.

9. Riou:y, D. S. Skin Biopsy in Leprosy. 3rd edn.Basle: Ciba-Geigy Ltd., 1900.

10. RIDLEY, D. S. and Joi'LiNG, W. 11. Classification ofleprosy according to immunity; a five-group sys-tem. Int. J. Lepr. 34 (1966) 255-273.

I I. SHIIGAI., V. N., REGii, V. L. and REYs, M. Correla-tion between clinical and histopathologic classifi-cation in leprosy. Int. J. Lepr. 45 ( 1977) 278— 280.

12. SRINIVASAN, 1 -1. R,,o, K. S. and IYLR, C. G. S. Dis-crepancy in the hi stopathological features of lep-rosy lesions in the skin and peripheral nerve. Re-port of a preliminary study. Lepr. India 54 (1982)275-282.

13. WHO Expert Committee on Leprosy. Sixth report.Geneva: World Ilealth Organization, 1988. Tech.Rep. Ser. 768.

New FAX Number for Editorial Office

Please note that the JOURNAL'S Editorial Office in Baton Rouge, Louisiana,U.S.A., has a new FAX number: 504-647-0430.