Mycobacteria

Nocardia

Actinomyces

Prof. Károly NAGY

Institute of Medical Microbiology Semmelweis University

NAGY KÁROLY

aerobic, rod shape(0.4x3 μm), no spores or cilias

Can not be stained by Gram , once stained, reisist decoloration by acid or alcohol

Acid-fast bacteria

high level resistance towards chemicals

MYCOBACTERIA (> 50 species, saprophitic)

Pathogenicity Species Reservoire Disease

Pathogenic M.tuberculosis human tbc

M.leprae human lepra

M.bovis bovine, human intestinal-,miliary tbc

Potentially M.avium- soil, birds, water disseminated and lung tbc

Pathogenic intracellulare bovine (frequent in AIDS )

M.kansasii water, bovine lung tbc

M.marinum fish, water sc.nodules, skin ulcers

M.scrofulaceum soil, water granuloma, cervical ly.ad

M.ulcerans human, environment sc.nodules, skin ulcers

M.fortuitum-chelonei soil, water, animals sc.abscess,disseminated

Stained by Ziehl-Neelsen acid-fast dye

lipid bilayerplasma memrane

peptidoglycan

Lipid+LPS

Mycolic acid(mycolyltrehalose:

„cord-factor”)

porins

D-arabinose

D-galactose

acyl lipids

Gram negatíve Gram positive Complex (acid-fast)

Ziehl-Neelsen stain

„Cord-formation”

M. tbc

Mycobacterium tuberculosis

Culture: aerobic, slow growth : cell division 18 h

Solid medium

Löwenstein-Jensen (egg,potato extract

Malachit-green, antibiotics)

3-8 weeks

Broth media

Sula (semisynthetic, Malachit-green)

Growth: clamps, bigger volumes

Mycobacterium tuberculosisPathogenesis

alveols

granuloma

lympnodes

caverna

Source of infection:

Sick human

animal

Infection

Aerosol droplets

dust

per os (milk)

contacts

Tbc develops in < 5% of those infected

Lung granuloma

Mycobacterium tuberculosis

Pathogenesis

2-4 weeks post infection:

CD4 T-cell cytokins activate macrophages

Granuloma and caverna formation:

cytokine toxycity, complement activation,

ischemia, macrophage enzyme activity,etc.

High number of bacteria in sputum:

primer and secunder infection,

high resistance towards drying and chemicals !

Surviving in phagolysosomes

alveolar macrophage

Mycobacterium tuberculosis: Pathogenesis

Focal,cheesy necrosis:

Caverna formation

Mycobacterium tuberculosis (tbc): Clinical picture

Pulmonal: lung (middle/lower lobes), lymphnodes, pleura

Symptomes: weakness, fatigue,weight loss, caughing, spitting: yellow/green mucus,

blood in the sputum, short breath, night sweating, pain in chest, back

• clinical diagnosis

• x - ray

• microscopy

• culture

In those infected disease develops <2years: 5%, > 2 years : additional 5-10%

Extrapulmonal : haematogen or urogen dissemination, contact infection

• gastrointestional (infected milk)

• genito-urinary system (kidney tbc)

• bone (deformity)

• skin tbc (erythema multiforme, aquarium disease)

• scrofula (neck swelling, ulcer)

Mycobacterium tuberculosis (tbc): Clinical picture

IMMUNITY

PRIMER

SECUNDER

Source of

infection

Gate of

entrance

M. tuberculosis: surviving strategies in macrophages

- high resistency of lipid/wax cell wall

- neutralisation of free radicals

- ammonia formation, which inhibits

* formation of phagolysosomes

* activity of lysosomal enzymes

„dormant” state

I. type II.type III. type IV.type

hypersensitivity

anaphylaxias cytotoxikus immunkomplex delayed, tuber-

culin type

IgE IgG IgG -

- Complement Complement -

- - - T lymphocyte

pollen,animal Rh, bact.,virus, intracellular

fur, penicillin gyógyszer fungi, etc, microbe

animal sera animal sera

local,gene- self cell Co activation granuloma

ralised, ADCC formation

odema, his- lysis trombocyte

tamin activation

skinprobe - - skinprobe

M. tuberculosis INDUCED IMMUNE DESTRUCTION

Tuberculin test: Mantoux - probe

Suitable to detect tbc infection or validation of the effect of BCG vaccination

Purified,standardised tuberculoprotein : M.tbc PPD (Purified Protein Derivate)

5 TU intracutan inoculation, < 10 mm induration: negatív

read after 48 h 10-20 mm induration: BCG-hypersensistivity

> 20 mm induration: infekctious hypersensitivity

Not M. tbc specifc

Conversion (pozitív): M.tbc infection, BCG vaccination

Reversion (negatív): early infection, miliary tbc, meningitis, AIDS, immunosuppression,

morbilli,varicella, wooping cough , influenza, helmintiosis, old age

THE HISTORY OF TUBERCULOSIS

•B.C. 1000 egyptian mummies – bone destrucion, abscess

•Hyppokrates: aerosol, droplets infection

•Middle ages: „phtysis”, the disease of the lung

•Franz de la Boë (1614 – 1672) : „tuberculum”

•London, XIX.c.:every 3. death due to tbc

•Johan Lukas Schönlein (1793 – 1864): the clinical

definition of tuberculosis (1832)

•1882: Robert Koch: a ‘Koch-bacillus” the etiological factor

1890 – tuberculin, 1930- diagnostical meaning

•1906: Albert Calmette és Camille Guerin: a „BCG”,

the possibility of active immunization (1921)

•1930: a Lübeck catastrophy: the significance of virulent/

avirulens strains, not interchangeable

•1930: introduction of tbc screening programs,epidemy decrease

•1945: WW II: epidemy increase

•1950-1980: significant decreasing

•1992: WHO Tbc: global problem

•2000: WHO AIDS – Malaria – TBC GLOBAL EMERGENCY

Famous people who have had tuberculosis :

Calvin

Anton Chehov

Branwell Bronté

Emily Bronté

Frédéric Chopin

Descartes

John Keats

D.H. Lawrence

Vivien Leigh

Nelson Mandela

Moliere

George Orwell

Paganini

Edgar Allan Poe

Richelieu cardinal

Schiller

Jean J. Rousseau

Sir Walter Scott

P.B.Shelly

Spinoza

R.L. Stevenson

Desmond Tutu

Simonetta Vespucci

Margaret Gardner (a former Ms. World)

EPIDEMIOLOGY : TB Incidence 2001

25 - 49

50 - 99

100 - 299

< 10

10 - 24

per 100 000 pop

> 300

Tbc prevalence - Hungary

Tbc split by gender and age

MALES FEMALS

RISK FACTORS

HOMLESS

DIRECT CONTACT

IMMIGRANT

LONELY

„Frigyes Korányi” National TBC and Pulmonological Institute

INCIDENCE OF TUBERCULOSIS TB is responsible for 25% of adult deaths in the developing world- more than those caused

by diarrhea, malaria and AIDS combined

South Africa has one of the highest incidences: >200/100 000

35 people die of TB every day in South Africa

The incidence in the 'first world' is less than 10/100 000

THE GLOBAL EMERGENCY1. 8-12 million new infections with M. tuberculosis per year

2. 2-3 million people die from TB per year

3. If present trends continue, deaths will exceed 4 million by 2004

4. There is also the emergence of multi-drug resistant M. tuberculosis

5. These trends, and the association of TB with HIV infection, has led to TB being declared

A GLOBAL EMERGENCY

by the World Health Organization

(1993)

Laboratory diagnosis

The basics of the effective treatment of tbc: early, rapid and accurate diagnosis

Microscopy of stained smear Isolation, culture

sensitivity104 bacterium/ml 102 bacterium/ml

low sensitivity long culture time: 4-8 hét

Cytocentrifuge (Sauton – and Dubos media )

Laboratory diagnosis

BacTec automats: radioactive palmitinic acid/CO2

fluorescent detection

turbidity

other color reaction

Rapid growth detection

4-14 nap

Biosensors:

Molecular detection: PCR, LCR

RFPL, DNA typing, DNS-chip

Drug sensitivity/ resistance

determination

( hours, 1-2 days)

< 1 h

Atypical and apathogenic mycobacteria

M. avium-intracellulare, M. kansasi , M. scrofulaceum

M. smegmatis, M. phlei, stb

induce mycobacteriosises

characteristics: occurrence in the nature

faster growth

pigment formation

niacin negativity

different drug resistance

member of the normal flora

disease: local (skin, lung, lymphnodes, etc.) processes

no transmission from human to human,

nozokomial infections

generalized in AIDS

THERAPY

• Stop infectivity

• Inhibit drug resistance

• Prevent remission of infection

• Goal : complete recovery

Combination treatment, long time (6 -12 month) treatment

Initial, intense phase:

3 -4 anti tuberculotics against extracellular bacteria

Stabilisation phase:

fewer drugs against intracellular, slow growing bacteria

INH (isonikotinic acid hidrazid ) - Rifampicin - Pirazinamid

Ethambutol (AIDS, extrapulmonal tbc, meningitis)

Ciprofloxacin,ethionamid,cycloserin (Multiresistant M.tbc)

Clarithromycin,rifampicin,etambutol,clofazimin (M. avium-intracellulare)

Doxicyclin ( M. fortuitum-chelonei)

Multiresistant strains !

TBC – AIDS coinfections

PREVENTION

2. Vaccina: BCG inoculation

M.bovis live, attenuated strain BCG (Bacillus Calmette-Guerin)

2 - 42 day after birth, partial resistency

3. Chemoprofilaxis:

INH monotherapy , Rifampicin (min. 6 month)

1. Prevention of infection:

General hygienic rules

Effective treatment of those infected

Eradication of infected cattles

Induces lepra (Hansen disease) , does not grow in media or cell culture,

Only in mouse sole and in armadillo.

Aerob, pálcika alakú, saválló baktérium : Ziehl – Neelsen festés

Laboratory diagnosis: from skin disorders, nose mucosa

Syphilis serological reactions are fals posistive in lepra

The bacteria grow intracellularly in skin histiocytes, endothel cells and superficial

nerves (Schwann-cells) . Optimal temperature: 30 C°

Tuberculoid lepra: normal cellular immunity,

few bacteria growing,

giant cells in granulomas

Lepromin skin tests: positive

Lepromatic lepra: immune response towards M.leprae is weak

skin, mucosa : large number of bacteria (histiocytes)

Lepromin skin test: negative

Immune response to only M.leprae is defective,

cellular and humoral immune response towards other

microorganisms are intact

Antibodies are not protective

Macular skin disorders:

Insensibility ulcer

Long incubation time: 10-15 year ! Gradual disease formation

Nodular skin disorders: „ lion face” (facies leontina)

Fingers, extremities

exposed to amputation

because trophical

disorders,

resorption of bones

resulting in

loss of nose cartilags

or digits

Boswelia carteri (Tömjénfa)

„Salai guggul”

Dapson (sulfonamid residue)

Rifampin (inhibitor of bacterial RNS synthesis

Clofazimin

Nocardia genus

Obligate aerob, Gram positive, moderate acid fast , filamental bacteria

Occurrence: widespread, soil, water

Domestic animals, dogs, cows (natural hosts)

In Humans: N.asteroides N. braziliensis

Nocardiosis: chronic, lobular pneumonia, miliary tbc-like

fever, weigh loss, chest pain. Lung abscess, haematogen

dissemination:central nerve system abscesses

Mycetoma: abscess in hand, leg, s.cutan connecting tissues

Laboratory diagnosis: sputum, pus, liquor smears

Gram- and acid fast staining

Treatment: Surgical removal

trimetoprim

sulfonamids

ActinomycesAnaerobic, no spores, Gram positive, irregular shape rods

Actinomyces israelii: non obligate anaerobic, slow growth (7-10 days)

Actinomycosis

Gram positive

Gram negative

Actinomyces mycelium

Pathogenesis:

2 -3 mm, yellow granules (mycelia) consisting of the bacterial bodies

ActinomycosisPathogenesis: typical endogenous infection. Caries teeth, pharyngeal lavage, intestines,

Vaginal flora

Pathogenic process is initiated by: trauma, pyogenic infections, i.u. contraceptive devices

ABSCESS FISTULA DRAINING OF PUS

Lung actinomycosis

Pelvic inflammation

SKIN

actinomycosis

Therapy:

• Surgical removal

• Penicillin

• sulfonamids