1. Mycobacterium leprae For MBBS (05-12-2017) By: Dr Puneet Kumar Gupta
Assistant Professor, Microbiology

3. Disease of Historical importance
World's oldest recorded disease
Stigmatized disease
Gerhard Henrick Armauer Hansen (1873-Norway)

4. The Bacterium

5. Armauer Hansen in 1868
Morphology : Straight rods x µm Single / groups. Intracellular. Acid fast bacilli with 5% H2 SO4. As agglomerates, bacilli being bound together by a lipid like substance (Glia) – called GLOBI

6. Parallel rows of bacilli in globi: CIGAR BUNDLE appearance – as in tissue section clumps of bacilli resemble cigarette ends
GLOBI is seen in Virchow’s lepra cell or foamy cells (Large undifferentiated histiocytes)

10. Cultivation
No artificial media / tissue culture available. Generation time: days Mouse : Intradermally into Foot pads. Granulomatous lesions in months. Intact CMI : Limited replication. ↓CMI : Generalized leprosy. Armadillo: Highly susceptible. Chimpanzees, Mangabey monkey.

11. Important Experimental Animal

12. Most Important experimental Animal

13. Adaptation in artificial media: ICRC, Bombay 1962
Adaptation in artificial media: ICRC, Bombay – AFB from leprosy patients were isolated in human fetal spinal ganglion cell culture= ICRC bacillus (LJ adapted)

14. Warm humid environment 9 - 16 days. 46 days in Moist soil
Warm humid environment days days in Moist soil hours in Sunlight minutes U V rays
Resistance

15. LEPROSY

16. Lepers are outcasts ?

17. Epidemiology
Exclusively Human disease & only source is a patient Exact mode of transmission – not clear; probably via -Nasal secretions. (One nasal blow may release 8 x 108 bacilli) Entry via – respiratory tract or skin Asymptomatic infection not uncommon

18. Not very communicable – 5% spouses suffer
Incubation period is 3-5 years. (2to 40 yrs) Continuous close contact. Rare in children < 5 Years.
Confined to underdeveloped tropical countries & southern hemisphere currently
India
Prevalence 0.68/10000 population in 2012
32 states/UT achieved target of elimination
Chhattisgarh, Dadar & Nagar Haveli Prevalence >1/10000

19. Annual Report 2015-16 from NLEP GOI (as on 1st April 2016)
>1/10,000 Population (163 District out of 669)
Total cases 86028

20. Annual Report 2015-16 from NLEP GOI
>1-Chattisgarh, Dadar Nagar Haveli, Delhi, Odisha, Chandigarh, Lakshadeep

21. Classification of leprosy
Table 27.10

22. IV. WHO classification. Based on bacterial load. 1. Paucibacillary
IV. WHO classification Based on bacterial load Paucibacillary I, T T, BT 2. Multibacillary BB, BL, LL.
Table add

23. Clinically………………

24. Leprosy
Slow, chronic & progressive Granulomatous disease of Peripheral nerves,skin and Muco- cutaneous tissues (Nasal mucosa). It affects Skin, liver, testes ,bones.

25. Source : Nasal or Skin Pathogenesis
discharges from lesion. Portal of entry: Damaged
skin -Inoculation. Nasal mucosa- Inhalation

26. Pathogenesis contd….:
Infiltration of bacilli in cooler body tissues like skin (nose, outer ear), testicles & superficial nerve endings→ (maculae) visible lesions. A non-specific or Indeterminate skin lesion is the First sign of disease Schwann cell is target cell. Neuritis leads to Anesthesia & muscle paralysis.

27. CMI severely depressed High infectivity Tuberculoid leprosy
Lepromatous leprosy
Extensive
maculae,
papules or
nodules;
destruction of skin.
CMI severely depressed
High infectivity
Tuberculoid leprosy
Lesions are
large maculae on skin,
superficial nerve
endings.
CMI is intact.
Low infectivity
Regression
Progression

28. Lepromatous leprosy
Generalized form with decreased CMI. “Lepromata” : Granulation tissue with plenty of vacuolated cells, from MN cells to Lepra cells Ulceration Secondary infection & Mutilation of limbs. Skin lesions are extensive and bilaterally symmetrical.

29. Sites: Commonly face, ear lobules, hands and feet.
Symmetrical thickening of peripheral nerves & anesthesia
Bacilli invade mucosa of Nose , Mouth and Respiratory tract → shed in secretions.
Bacteremia present.
RE system, Eyes, testes, kidney & bone involved

30. Antibodies / other Abs are seen (exaggerated humoral response)
Lepromin test is negative. CD8+ cells in plenty
Antibodies / other Abs are seen (exaggerated humoral response)
BFP= syphilis tests (STS)
Infective form….more than other types – poor prognosis
Lateral part of eyebrows are lost

31. Lepromatous leprosy
Lepromatous leprosy

32. Complications : Acute exacerbations Testicular atrophy, Gynaecomastia Diffuse thickening of face – (Leonine face) Necrosis of nasal bones, cartilage with loss of upper incisors Corneal ulcers.

34. Localized form in individuals with intact CMI
Localized form in individuals with intact CMI. Skin lesions : Few hypo or hyper pigmented macular patches (anesthetic) Sharply demarcated Seen on Face, trunk and limbs. Bacilli are scanty or absent. (paucibacillary) Infectivity is low.
Tuberculoid leprosy

35. Diagnosed with Clinical + Histological evidences
Diagnosed with Clinical Histological evidences. Nerves : Peripheral Nerves to bigger nerves involved. Thickened, hard and tender. Deformities in hand & feet Lepromin test is positive. Auto antibodies production is rare. CD4+ cells.

37. Good prognosis

40. Peripheral neuropathy. V & VII th cranial nerve : Corneal ulcers
Peripheral neuropathy. V & VII th cranial nerve : Corneal ulcers. Ulnar nerve : Claw hand. Lateral popliteal nerve : Foot drop. Posterior tibial & medial nerve: Trophic ulcers, Loss of digits.
Complications

41. Dimorphous/Borderline type :
Dimorphous/Borderline type : Lesions resembles both LL (bacteriology) & T T (Clinically). May turn to complete LL or T T type (depending on host resistance or chemo therpay)

43. Cirular, sharply demarcated
Borderline lepromatous
Borderline tuberculoid leprosy
Lesions are Slightly
asymmetrical with or
without anesthesia.
Cirular, sharply demarcated
lesions. Raised erythematous border with anesthesia.

44. Indeterminate type:. Early stages : Maculoanesthetic patches
Indeterminate type: Early stages : Maculoanesthetic patches. Lesions are not like T T or LL Spontaneous healing Turn to either LL or T T type.

45. Indeterminate type

48. Immunity : High degree of innate immunity. Induces both AMI & CMI
Immunity : High degree of innate immunity. Induces both AMI & CMI. Antibodies are not effective. LL Pts : Large number of CD8 cells. TT Pts : Predominantly CD4 cells. Genetic relation: T T : HLA – DR2 L L : HLA MTI, DQ1

49. Differential diagnosis of Leprosy
Birth mark
T. versicolor
T.corporis

50. Pytiriasis alba
Vitiligo
Lichen planus

51. Fixed drug eruption
Psoriasis
Dermal leishmanoid
Lupus vulgaris

52. Kaposi’s sarcoma
Sarcoidosis

53. Lepra reactions: Acute inflammation of the disease due to Immunological reactions against bacilli. Medical emergency. Two types:

54. Jopling type 1: CMI response against bacilli
Synonym: Reversal reaction
Occurrence: Spontaneous, Chemotherapy
Seen in BT, BB, BL.
Due to influx of lymphocytes into lesions changed to T T morphology
Lesions are painful, tender Erythema and swelling.

57. Jopling type 2 Synonym: Erythema Nodosum Leprosum (ENL)
Due to vasculitis (Antigen – Antibody complex).
Seen in LL & BL few months after starting the chemotherapy

58. Characterised by: Tender, inflamed subcutaneous nodules Fever
Lymphadenopathy, arthralgia. (Ag from dead bacilli – Arthus type response)
IgG, neutrophil & C in lesions

60. Lucio phenomenon: Cutaneous hemorrhagic infarct in LL cases.

61. Main features of lepra reactions. Type 1 Type 2
1.Immunological basis : CMI Vasculitis with
Ag – Ab deposits.
2. Type of patient :
BT,BB, BL BL, LL.
3. Systemic disturbances :
Not seen . Present.
4. Hematological Not present Present
disturbances:
5. T Helper response TH1 predominate TH2
6. Proteinuria Not seen. Frequently present.
6.Relation to therapy Seen in first Rare in first
6 months months

62. Lab diagnosis Microscopy Culture Serology (Ab detection)
Molecular method
Demonstration of CMI

63. Lab diagnosis
Bacteriological Diagnosis is easy in LL types but difficult in TT.
Specimen:
smears collected from Nasal mucosa, Lesion, Skin (slit smear of ear lobule, forehead, Cheek, Chin, buttock) = 5-6 sites
Sample from thickened nerve or Nodular lesion are collected for H/P

64. Nasal mucosa (nasal Blow or Nasal Scrapping)
A blunt, narrow scalpel is introduced into the nose and internal septum
Scraped sufficiently to remove a piece of mucous membrane, which is transferred to a slide and teased out into a uniform smear.

65. Taken from Edge of lesion
Slit Skin smear:
Taken from Edge of lesion
Skin is pinched up tight to minimize bleeding
a cut about 5 mm long made with a scalpel, deep enough to get into the infiltrated layers.
Wipe off blood or lymph that may have exuded
Scalpel blade is turned transversely to scrape the sides and bottom of the cut for tissue pulp
smeared uniformly on a slide.
About 5-6 different areas of the skin buttocks, forehead, chin, cheek and ears.
Collection of skin smears

66. Smears are stained by the Ziehl-Neelsen technique using 5% sulphuric acid.
Biopsy Nodular lesions and thickened nerves, and lymph node puncture may be necessary

67. Z-N staining: Decolorizer =5% H2SO4
Acid fast bacilli within the undifferentiated macrophages: L L
Live bacilli : Solid, uniformly stained, parallel side, rounded ends, length five times width
Dead bacilli :Fragmented and granular

69. Grading 1-10 / 100 oil immersion fields : 1+ 1 -10/10 “ “ : 2+
1 -10/10 “ “ : 2+
1 -10 / 1 “ “ : 3+
10-100/ field : 4+
/field : 5+
>1000, clumps/globi in every field: 6+

70. Load of bacilli:
1. Bacteriological index (BI): total no of pluses (+) scored in all the smears divided by no of smears; Minimum 4 skin lesion, nasal scrap & both ear lobule must
2. Morphological index(% of uniformly stained bacilli)
= Uniformly stained bacilli X 100
Total number of bacilli
(= SFGB/Total x100)

71. Skin & Nerve biopsy.

72. Lymphohistiocytic infiltrate surrounding a nerve fiber

74. Culture: No Culture media Animal inoculation: Advantage: Disadvantage:
Mouse foot pad:
9 banded Armadillo
Advantage:
10 times more sensitive
Drug resistance detection
Evaluation of drug potency
Check Viability
Disadvantage:
Time consuming (6-9 months)
Ethical issue: animals used

75. LESIONS DEVELOPING FOLLOWING INOCULATION IN FOOT PAD OF MICE

76. Serological test : Antibodies against phenolic glycolipid Ag
-ELISA (Antibody against PGL-I)
Sensitivity LL: 95%
TT: 60%
-FLA-Abs-Fluorescent leprosy Ab Absorption Test
Detect specific Ab irrespective of duration and stage of disease
92% sensitive & 100% specific
Molecular diagnosis:

77. Detection of CMI (Lepromin test) :
Detection of CMI (Lepromin test) : Skin test for delayed hypersensitivity to lepra bacilli Antigens: Boiled extract of Lepromatous tissue in isotonic saline Leprosins : Ultrasonicates of tissue – free bacilli from lesions a). leprosins – H b). leprosins – A 3.Dharmender’s antigen. 4.Soluble antigen.

78. Two types of reactions on Intradermal injection 1
Two types of reactions on Intradermal injection 1. Early reaction of Fernandez : Erythema & Induration within days Remains for days. Poorly defined with little significance Late reaction of Mistuda. Erythematous, indurated , granulomatous nodular skin lesion. Seen in weeks reaches to peak in 4 weeks. Indicates CMI status in leprosy patients.

79. Significance : 1. To classify the lesions of leprosy
Significance : To classify the lesions of leprosy. T T ( + ) L L ( - ) Borderline (+/-) 2. To assess prognosis & response to treatment. Positive: Good prognosis Negative: Bad prognosis 3. To assess the resistance of individuals to leprosy Identify candidate lepra bacilli

80. Treatment : Until 1982 : Dapsone only.
Now MDT being given because of resistant strains.
WHO recommended Multi drug therapy
Paucibacillary case. (I, TT, BT)
Rifampicin 600 mg/ month
annually
Dapsone 100mg / day till 2year

81. Multi bacillary case: (BB, BL, LL) Rifampicin 600mg / month
Dapsone 100 mg / day
annually
Clofazimine 300 mg / month till 5 years +
50 mg / day
(Ethionamide/prothionamide)

82. Vaccines: BCG, MAI complex vaccine.
Mycobacterium w vaccine.
Chemoprophylaxis: Dapsone ; in TT variety only

83. THANKS