2. INTRODUCTION
Tuberculosis is a chronic Infectious disease
• caused by M.tuberculosis/M.bovis
• mainly affecting the lung causing Pulmonary TB
• also affect other parts causing Extra Pulmonary TB
Characterized by
•Cough lasting > 3 wks and not respond to usual antibiotic.
•Production of purulent, sometimes blood- stained sputum
•Evening rise of temp.
•Night sweats
•Weight loss
3. CHARECTERISTICS OF M. TUBERCULOSIS
gram +ve bacilli
Non motile, non sporing,&
noncapsulated
Strict aerobes
Branching filamentous forms ≈
fungal mycelium
=>MYCOBACTERIUM
A.F.B => when stained by Carbol
Fuschin by
Z-N Stain they resist
decolorisation by 25% H2S04
&Abs.alcohol
Cell wall is lipid rich with mycolic
acid which is essential & unique
component
4. CAUSES:
The primary cause of TB, Mycobacterium tuberculosis , is a
small aerobic non-motile bacillus.
The M. tuberculosis complex includes four other TB-causing
mycobacteria: M. bovis, M. africanum, M. canetti and M.
microti. M. africanum is not widespread, but in parts of Africa it
is a significant cause of tuberculosis.
The high lipid content of this pathogen accounts for many of its
unique clinical characteristics.
M. microti is mostly seen in immunodeficient people, although
it is possible that the prevalence of this pathogen has been
underestimated.
6. Signs and symptoms:
When the disease becomes active, 75% of the
cases are pulmonary TB, that is, TB in the lungs.
Symptoms include chest pain, coughing up
blood, and a productive, prolonged cough for
more than three weeks.
Systemic symptoms include
fever, chills, night sweats, appetite
loss, weight loss, pallor, and often a tendency
to fatigue very easily.
In the other 25% of active cases, the infection moves from the lungs, causing other
kinds of TB, collectively denoted extrapulmonary tuberculosis. This occurs more
commonly in immunosuppressed persons and young children.
Extrapulmonary infection sites include the pleura in tuberculosis pleurisy,
the central nervous system in meningitis, the lymphatic system in scrofula of the
neck, the genitourinary system in urogenital tuberculosis, and bones and joints
in Pott's disease of the spine.
7.
8. Transmission of the disease
Pulmonary tuberculosis is a disease of
respiratory transmission, Patients with the
active disease (bacilli) expel them into the air
by:
– coughing,
– sneezing,
– shouting,
– or any other way that will expel bacilli into
the air
Transmission is dependent on closeness and
time of contact
Once inhaled by a tuberculin free person, the
bacilli multiply 4 -6 weeks and spreads
throughout the body. The bacilli implant in
areas of high partial pressure of oxygen:
lung
renal cortex
reticuloendothelial system
9. EPIDEMIOLOGY:
It is currently estimated that 1/2 of the world's population (3.1 billion) is
infected with Mycobacterium tuberculosis. Mycobacterium avium complex is
associated with AIDS related TB.
The proportion of people who become sick with tuberculosis each year is
stable or falling worldwide but, because of population growth, the absolute
number of new cases is still increasing.
In 2007 there were an estimated 13.7 million chronic active cases, 9.3 million
new cases, and 1.8 million deaths, mostly in developing countries.
The distribution of tuberculosis is not uniform across the globe; about 80% of
the population in many Asian and African countries test positive in tuberculin
tests, while only 5-10% of the US population test positive.
10. Most TB cases were in India and China
10 000 - 99 999
100 000 - 999 999
< 1 000
1 000 - 9 999
No estimate
Number of cases
1 000 000 or more
Asia
59%Africa
21%
11. Problem of TB in India
• Estimated incidence
– 1.96 million new cases annually
– 0.8 million new smear positive cases annually
– 75 new smear positive PTB cases/1lakh population per year
• Estimated prevalence of TB disease
– 3.8 million bacillary cases in 2000
– 1.7 million new smear positive cases in 2000
• Estimated mortality
– 330,000 deaths due to TB each year
– Over 1000 deaths a day
– 2 deaths every 3 minutes
Gopi P et al (TRC), IJMR, Sep 2005
12. Problem of TB in India (contd)
• Prevalence of TB infection
– 40% (~400m) infected with M. tuberculosis (with a 10% lifetime risk
of TB disease in the absence of HIV)
• Estimated Multi-drug resistant TB
– < 3% in new cases
– 12% in re-treatment cases
• TB-HIV
– ~2.31 million people living with HIV (PLWHA)
– 10-15% annual risk (60% lifetime risk) of developing active
TB disease in PLWHA
– Estimated ~ 5% of TB patients are HIV infected
13. India is the highest TB burden country accounting for more
than one-fifth of the global incidence
Indonesia
6%
Nigeria
5%
Other countries
20%
Other 13 HBCs
16% China
14%
South Africa
5%
Bangladesh
4%
Ethiopia
3%
Pakistan
3%
Phillipines
3%
India
21%
Source: WHO Geneva; WHO Report 2009: Global Tuberculosis Control; Surveillance, Planning and Financing
Global annual incidence = 9.4 million
India annual incidence = 1.96 million
India is 17th
among 22
High Burden Countries
(in terms of TB
incidence rate)
14. PATHOGENESIS OF TUBERCULOSIS
Pathogenesis in a previously unexposed
,immunocompetent person depends on the
development of anti-mycobacterial cell
mediated immunity,which confers resistance to
bacteria and development of hypersensitivity to
mycobacterial antigens.
Pathologic manifestation of tuberculosis like
caseating granuloma and cavitation are result
of hypersensitivity that develops in concert
with the protective host immune response.
Macrophages are the primary cells infected
by M.tuberculosis.
15. Diagnosis of Pulmonary TB
Routine investigations- Hb, TLC,
DLC (lymphocytosis), ESR.
Chest x-ray-
• Abnormalities often seen in apical
or posterior segments of upper lobe
or superior segments of lower lobe.
• May have unusual appearance in
HIV-positive persons.
• Cannot confirm diagnosis of TB.
15
Arrow points to cavity in
patient's right upper lobe.
16. TUBERCULIN (MONTOUX )TEST
The Mantoux skin test
consists of an intradermal
injection of 5 IU PPD is
extensor aspect of forearm
tuberculin.
The size of
induration is
measured 48–72
hours later.
Erythema (redness)
should not be
measured.
Mantoux test
injection site in a
subject without
chronic conditions or
in a high risk group
clinically diagnosed
as negative at 50
hours.
17. SPUTUM EXAMINATION – Sputum examination are essential to confirm TB
Best collected in morning before any meal.
Sputum examination on 3 days increase chances of detection.
Sputum can be collected from laryngeal swab or bronchial washing.
In small children, gastric lavage can be examined.
Smear should be prepared from thick dirty part of sputum & stained with Ziehl-Neelson
technique.
Culture - Use to confirm diagnosis of Tuberculosis.
Conventional cultures take up to 10 weeks.
Culture all specimens, even if smear report is negative.
Culture is done in Lowenstein Jansen media.
Susceptibility testing is essential.
Result in 4-14 days when liquid medium system is used.
For example- BACTEC can confirm TB growth within one week by indirectly
measuring TB bacilli growth in special bottles and medium.
18. Difficult to treat:
1. Most antibiotics are effective against rapidly growing organism in
contrast to M.tb slow growing
2. Mycobacterium Cell can be dormant, thus completely resistant to
many antibiotics or killed very slowly by few drugs
3. The lipid rich mycobacterium Cell wall is impermeable to many
drugs.
4. A substantial proportion are intracellular &chemotherapeutic agents
penetrate poorly
5. Mycobacterium =>develop resistance to any single drug
6. Caseation &fibrosis block the b.v. supplying necrotic area thus
penetration of antitubercular drug difficult
19. TREATING TB DISEASE
(GENERAL PRINCIPLES)
Always treat with multiple drugs.
Never add a single drug to a failing regimen.
DOTS (Directly Observed Treatment Shortcourse) is given.
Treatment course depends on the categories of the patient.
Usually 6 months, sometimes 9 months.
Four drugs for two months.
Isoniazid – Rifampicin – Ethambutol - Pyrazinamide
Two drugs for four or seven months.
Isoniazid - Rifampicin
19
20. Classification of Antitubercular
Drugs
First line Drug(Essential AntiTB)
High Anti TB effect
Acceptable degree of toxicity
Used routinely
- ISONIAZID(H)
-RIFAMPICIN(R)
-PYRAZINAMIDE(Z)
- ETHAMBUTOL(E)
- STREPTOMYCIN(S)
21. Contd.• SECOND LINE DRUG (RESERVE ANTI TB DRUG)
-low anti tb effect
- high toxicity
-or both
-used in special circumstances only
1. Fluroquinolone- Ciprofloxacin, Ofloxacin, Levofloxacin, Moxifloxacin
2. Amikacin
3. Capreomycin
4. Ethionamide
5. Para Amino salicylic Acid (PAS)
6. Cycloserine
7. Thiacetazone
Newer Drugs:
a) Linezolid
b) R-207910 (also known as TMC 2007)
22. ISONIAZID(INH)
Salient features:
1) Most active antitb drug
2)Important assets are
-potency
-infrequent toxicity
-low cost
3)Bactericidal for rapid growers
4)Useful for tb meningitis
5)Effective for both extra cellular & intracellular tb
6)If combined with other drug it has good
resistance
preventing action
23. Mechanism of Action
ISONIAZID
Kat G(catalase peroxidase
in mycobacteria)
Active INH
AcpM & Kas AcpM-Acyl Carrier protein
KasA( ßketoAcyl Carrier protein synthetase)
Block Mycolic Acid Synthesis
24. Pharmacokinetics
Absorption: complete orally. Oral dose=Parenteral dose
Distribution: penetrate all body tissue
Placenta
Meninges
Caseous tb lesion
Metabolism: In liver by N- Acetyltransferase, to acetylisoniazid. Generic
variation has been observed in its rate of N- Acetylation which is inherited as autosomal recessive trait.
• Indians are rapid acetylators while egyptians are slow acetylators.
• Excretion: 75-95% excreted in urine
-Dose adjustment is not required in Renal Failure
-INH & Acetyl Hydrazine are not bound to P.P, thus dialyzable
Contra Indication: - KNOWN HYPERSENSITIVITY
-ACUTE HEPATIC DISEASE
25. Drug interaction
• Inhibit metabolism of Warfarin,Diazepam,Disulfiram
• Abs.impaired by Al(OH)3
• PAS inhibits the metabolism of INH
26. Adverse Effect:-
I. Rash
II. Peripheral Neuropathy
III. Hepatitis
IV. Transient loss of Memory
V. Seizure
HEPATOTOXICITY
-Acetyl Hydrazine cause the damage
-↑in Serum Transaminase
-Can be fatal if not withdrawn promptly
27. Clinical Use
Therapeutic: Essential component of all
AntiTB Regimen
Prophylactic:
-Transmission to close contact
-Baby born to inf.mother
-Development of active TB in
immunodeficient individuals
Doses of INH
I. 5mg/kg/day
II. 10mg/kg/A.D
III. 10mg/kg/day –in serious infection
-If malabsorbtion is a problem
IV. Prophylactic: 5mg/kg/day
28. RIFAMPIN(R)
Semisynth. deri of Rifamycin B-from St.meditarranei
Bactericidal ,affect all subpopulation of
M.tb.acts best on Spurters &slow growing
Acts both extra &intracellularly
Good sterilising property &resistance preventing
action
Bactericidal efficacy ≈ INH
&>any other 1st
line drug
Analogue of RIFAMPIN isRIFABUTIN
obtained from Rifamycin S
30. M.O.A Of Rifampicin
Normal synthesis of RNA from DNA by DNA dependent RNA polymerase (DDRP)
D.N.A
DNA dependent R.N.A.polymerase
R.N.A
Protein Syn.
Cell multiplication
Rifampicin bind to β S.U of DDRP
Drug –Enz Complex
Suppression of chain initiation
31. Pharmacokinetics
Abs: -Well absorbed from g.i tract
-PAS interferes with abs.
-Food also interferes with abs.
Dist: -wide. Penetration to
•Cavities
•Meninges
•Caseous Mass
•Placenta
Rifampicin causes an orange red coloration of
body secretion due to various aspect of
Rifampin metabolism
32. P/K Contd.
Metabolism
Following abs. from G.I. Tract
Eliminated rapidly in the bile
&undergoes Enterohepatic Circulation
Rifampin is progressively
deacetylated
This metabolite is bactericidal
T1/2 varies from 1.5-5 hrs
EXCRETION: Urine-30%
Faeces 60-65%
Recycling through liver by excretion in bile, reabsorption from intestines
into portal circulation, passage back into liver, and re-excretion in bile.
33. Doses of Rifampin
Doses- 10mg/kg/day
10mg/kg/Alt.day
C/I –k/c/o history of h/s to Rifamycin
-Hepatic Dysfunction
Precaution –Careful monitoring of L.F.T.
-In elderly
- In alcoholics
-Pts. having hepatic disease
37. 2)Other indications
a)meningococcal meningitis-carrier state
600mg B.D for 2 days
b)H.influenzae meningitis –close contact
20mg/kg/dayfor 4days
c)Legionella infection -Along wiyh Erythromycin
d) Serious staphylococcal infection like
- osteomylitis
-prosthetic Valve Surgery
e)Brucellosis –Along with Doxycycline
f)MRSA
g)T/t of meningitis caused by highly penicillin resistant
strain
38. PYRAZINAMIDE(Z)
Synthetic analogue of Nicotinamide
Though weakly tuberculocidal
More active in acidic medium
Highly effective during 1st
2months
More effective against Slow Growing
Active both intra&extracellularly
Including Z in combination tharapy
-duration of t/t is ↓
-It has potent sterilising action
39. MOA Of Pyrazinamide
Pyrazinamide
Mycobacterial Pyrazinamidase
Pyrazinoic Acid
Inhibits Mycolic Acid Synthesis
Resistance due to mutation of gene pncA, A few
pyrazinamidase resistant strains with mutations in
the rpsA gene have also been identified.
40. Pharmacokinetics
Absorption: Well absorbed from g.i.tract
Distribution: good penetration to all body tissue
& CSF
Metabolism: Pyrazinamide
Pyrazinoic Acid
5-OH pyrazinoic Acid
T1/2 6-10hrs
Dose: 25mg/kg/day once Daily
35mg/kg/day thrice in a week.
41. Adverse Effects:
1)Hepatotoxicity: Most hepatotoxic
SGOT &SGPT
Serum Bilirubin
C/I-Not to be given with any degree of
hepatic dysfn
2)Inhibits the excren
of ureates
Hyperuracemia
Acute episodes of Gout
3)Joint pain ,Arthralgia
43. M.O.A of Ethambutol
Ethambutol
Mycobact. Arabinosyl Transferase
Polymerisation reaction of
Arabinoglycan
Essential component of
Mycobacterial Cell wall
Ethambutol inhibits the enzyme Mycobacterial Arabinosyl
Transferase, which is required for polymerisation reaction of
Arabinoglycan
44. Pharmacokinetics
Abssorption: Well absorbed from g.i.t.
Distribution: Wide,penetrates the meninges
Metabolism: Hepatic
T1/2~ 4hrs
Excretion :-unchanged in urine(3/4th
)
-Excreted by G.F& T.S
-Dose to be reduced in Renal failure
C/I ; Cr. Clearance <50ml/min
Doses of Ethambutol : usual daily dose - 15mg/kg/day
30mg/kg/day can be given thrice in a
week orally.
45. Adverse Effects:
1)RETROBULBAR NEURITIS :causing
-Loss of Visual Acuity
- Red Green Color blindness
Early recognition &stoppage of drug-
visual toxicities is largely reversible
Contra-indication ;In children <6yrs
a) they are unable to report early.
b) may not permit the assessment of Vascular Acuity
& red green color blindness discrimination
2) Renal uric acid excretion
Hyperuricemia
3)Pruritus, Joint Pain
46. First-line Supplement Drug
Aminoglycoside from Str.griseus
1st
clinically active against Mycobact.
Limitation of its use
i)dose related toxicity
ii)devlopment of resistant org.
iii)pt compliance is poor due to i.m
Present status:
-Least used 1st
line A.T.D
-More active against extracellular bacilli
-Inactive against intracellular bacilii
STREPTOMYCIN(S)
1.Streptomycin
2.Rifabutin
3.Rifapentine
47. Mechanism of Action of Streptomycin
Streptomycin is a protein synthesis inhibitor. It binds to the small 16S
rRNA of the 30S subunit of the bacterial ribosome, interfering with the
binding of formyl-methionyl-tRNA to the 30S subunit.
-Protein Syn . Is hampered
*Interferes with chain initiation
*Induce misreading of mRNA
* Incorporation of incorrect Amino Acid into peptide
Formation of Nonfunctional /toxic protein
*Cause break up of polysomes into monosomes
IRREVERSIBLE &LETHAL FOR CELL
This results in an unstable ribosomal-mRNA complex, leading to
a frameshift mutation and defective protein synthesis; leading to
cell death.
48. Pharmacokinetics
Neither absorbed / destroyed in G.I.Tract.
Absorption from inj site is rapid (30-60min)
Distributed to Extracellular TB cavities.
Not metabolized, Excreted unchanged in urine
49. Adverse Effects:
i)OTOTOXICITY-drugs get conc. In labrynthine fluid, both vestibular &
cochlear damage
ii)NEPHROTOXICITY
iii)Neuro Muscular PARALYSIS -Ach release,
sensitivity of post.syn. receptors.
iv)Sterile abscess at the inj. site
Contra Indication:
- Not to be given in pregnancy
-Avoid use with other ototoxic drug eg;High ceiling
diuretics,Minocycline,Cisplatin
-Avoid use of other nephrotoxic drug eg;Amphotericin B,
Vancomycin,Cyclosporin,Cisplatin
-Pts with renal disease.
-Cautious use with muscle relaxant.
50. Uses
Sensitive to M.tb
Mycobacterium Avium Complex
M.kansassi
It is as an important drug when inj. form is needed-
-especially with severe & life threatening
condition.
-TB meningitis
-Miliary TB
Dose:15mg/kg/D
15mg/kg/A.D
51.
52. Rationale behind Combination Therapy
To prevent emergence of resistant bacilli
Drugs like H & R act synergistically &
Z is more active during the inflammatory states
Duration of treatment is reduced
To act simultaneously with all subpopulation of
Mycobacterium tuberculosis
53. Aminoglycosides: least effective and more toxic
Capreomycin - Viomycin – Kanamycin
Adverse effects:
These drugs are: Nephrotoxic will cause
Proteinuria, Hematuria, Nitrogen metabolism,
and Electrolyte disturbances
However effect is reversible when drug is
stopped
Capreomycin has replaced viomycin because of less toxic effects,
but all three drugs have the same effects.
Second line drugs:
54. Can cause CNS disturbances
Therapeutic States :
Cycloserine should be used when re-treatment is necessary
or when the micro-organism is resistant to the other drugs.
It must be given in combination with other anti-tuberculosis
drugs.
Mechanism of Action :
An analog of D- alanine synthetase, will block bacterial
cell wall synthesis.
Cycloserine:
55. cys absorbed orally, diffuses all over.
About 1/3 of a dose is metabolised the rest is excreted
unchanged by kidney.
Toxicity:
Most common in the CNS: Headache, Tremor,
Vertigo, Confusion, Nervousness,
Pharmacokinetics:
56. These are first anti tubercular drugs.
It is a tuberculostatic drug.
Low efficacy drug.
Side effects:
hepatitis,
optic neuritis,
mental disturbences
impotence
Thioacetazone & Ethionamide:
57. PAS is a tuberculostatic and one of least active
drugs.
It inhibits denovo folate synthesis.
PAS is completely absorbed by oral route and
distributed all over .
T1/2 is 1hr.
Patient acceptability of PAS is poor.
Adverse effects ;
Rashes, fever, liver dysfunction
Para-amino salicylic acid:
58. Chemotherapy
DOTS (Directly Observed Treatment Shortcourse) :
To control tuberculosis requires:
Effective, inexpensive, simple and standardised technology.
The success of the DOTS strategy depends on:
Government commitment to a national tuberculosis
programme.
Case detection –finding by smear microscopy examination
of TB susceptible in general health services.
Regular uninterrupted supply of essential anti-TB drugs.
Monitoring system for programme supervised and
evaluation.
59. Short Course Chemotherapy:
These are regimens of 6-9 month duration.
All regimens have an initial intensive phase
lasting 2-3 months to kill the TB bacilli and
afford symptomatic relief.
This is followed by continuation phase for 4-6
months so that relapse does not occur.
61. Resistance to both Isoniazid and Rifampin and number of
other anti-TB drugs . MDR-TB has a more rapid course ,(some
die in 4-16 weeks).
Treatment is difficult as second line drugs
are less efficacious, less convenient, more expensive and
toxic.
Therapy depends on drugs used in earlier regimen, dosage and
regularity with which they have been taken.
In India>200,000patients have been treated under DOTS by
early 2001 with cure rate of 75-80%.
In other countries 80-93%cure rates have been obtained.
Multiple Drug Resistance(MDR):
62. Extensively Drug Resistant TB (XDR TB) is a form of TB
caused by bacteria resistant to all the most effective Drug [i.e.,
MDR-TB plus resistance to any Fluroquinolone (FQ) and any
of the second line anti TB injectable drugs: Amikacin,
Kanamycin, Capreomycin
Extensively Drug Resistant TB (XDR- TB)
63. MDR/XDR Treatment Strategies: WHO
Three approaches to treatment:
Standardized regimens
Empiric regimens
Individualized treatment regimens
(based on DST results)
The choice among these should be based on:
Availability of second-line drugs
Local drug-resistance patterns, and the history of use of
second-line drugs
Drug susceptibility testing of first- and second-line drugs
64. Use any
available
One of
these
One of
these
First-line
drugs
Fluoroquinolones
Injectable
agents
Pyrazinamide
Ethambutol
Levofloxacin
Moxifloxacin
Ofloxacin
Amikacin
Capreomycin
Streptomycin
Kanamycin
Building a Regimen for MDR-TB
STEP 1
Begin with any
first-line agents
to which the
isolate is
susceptible
Add a
fluoroquinolone
and an
injectable drug
based on
susceptibilities
PLUS PLUS
65. Pick one or more of these
Oral second-line drugs
Cycloserine
Ethionamide
PAS
Building a Regimen for MDR-TB
STEP 2
If 4 drugs are
not identified in
Step 1:
Add second-line
drugs until you
have four to six
drugs to which
the isolate is
susceptible (and
preferably which
have not been
used to treat the
patient
previously)
66. Consider use of these
Third-line drugs
Clofazimine
Linezolid
Amoxicillin/
Clavulanate
Imipenem
Clarithromycin
STEP 3
Building a Regimen for MDR-TB
If there are
not four to six
drugs available
in the above
categories,
consider
third-line
drugs in
consultation
with an
expert.
67. Building a Regimen for XDR-TB
STEP 1
Begin with any
first-line agents
to which the
isolate is
susceptible
Add a
fluoroquinolon
e and an
injectable drug
based on
susceptibilities
Use any
available
One of
these
One of
these
First-line
drugs
Fluoroquinolones
Injectable
agents
Pyrazinamide
Ethambutol
Levofloxacin
Moxifloxacin
Ofloxacin
Amikacin ?
Capreomycin ?
Streptomycin ?
Kanamycin ?
Commonly not
susceptible
By definition
there is
fluoroquinolone
resistance
Select agent
based on history
and susceptibility
testing
PLUS PLUS
68. STEP 2
Building a Regimen for XDR-TB
Add second-
line drugs until
you have four
to six drugs to
which the
isolate is
susceptible
(and
preferably
which have
not been used
to treat the
patient
previously)
Pick one or more of these
Oral second-line drugs
Cycloserine
Ethionamide
PAS
With XDR-TB, often
all three of these agents
are necessary
69. STEP 3
Building a Regimen for XDR-TB
If there are
not four–six
drugs available
in the above
categories,
consider third-
line drugs in
consultation
with an
expert.
Consider use of these
Third-line drugs
Clofazimine
Linezolid
Amoxicillin/
Clavulanate
Imipenem
Clarithromycin
70. • Ensure laboratory services for hematology,
biochemistry and audiometry are available
• Establish a clinical and laboratory baseline before
starting the regimen
• Initiate treatment gradually when using drugs that
cause gastro-intestinal intolerance
• Ensure availability of ancillary drugs to manage
adverse effects
• Use DOT for all doses
Initiating Treatment: WHO
71. • Isolate until three consecutive sputum AFB smears
(or documented culture conversion) are negative
and there has been a good clinical response to
treatment
• Initiate MDR-TB treatment under close supervision
to provide patient education and monitoring and to
treat drug toxicity
• Tailor toxicity monitoring to specific drugs employed
• Seek consultation with an expert as soon as drug
resistance is known
MDR/XDR-TB: Management Principles
72. • Use daily patient-centered DOT throughout entire
treatment course
• Record drugs given, bacteriological results, chest
radiographic findings, and the occurrence of
toxicities
• Optimize management of underlying medical
conditions (example: diabetes) and nutritional
status
MDR/XDR-TB: Management Principles
73. MDR/XDR-TB: Monitoring
• Collect sputum specimens for smear and culture
periodically during treatment once culture negative
• Obtain end-of-treatment sputum specimen for
smear and culture
• Perform chest radiograph periodically during
treatment and at end of treatment
• Resources permitting, monitor minimum of two
years following treatment (quarterly during first
year, every six months during second year)
75. Evolution of TB Control in India
• 1950s-60s Important TB research at TRC and NTI
• 1962 National TB Programme (NTP)
• 1992 Programme Review
• only 30% of patients diagnosed;
• of these, only 30% treated successfully
• 1993 RNTCP pilot began
• 1998 RNTCP scale-up
• 2001 450 million population covered
• 2004 >80% of country covered
• 2006 Entire country covered by RNTCP
76. Objectives of RNTCP
• To achieve and maintain a cure rate of at least
85% among newly detected infectious (new
sputum smear positive) cases
• To achieve and maintain detection of at least
70% of such cases in the population
77. RNTCP Organization structure: State level
Health Minister
Health Secretary
MD NRHM Director Health
Services
Additional / Deputy / Joint
Director
(State TB Officer)
State TB Cell
Deputy STO, MO, Accountant,
IEC Officer, SA,
DEO, TB HIV Coordinator etc.,
State Training and Demonstration
Center (TB)
Director, IRL Microbiologist, MO,
Epidemiologist/statistician, IRL LTs etc.,
78. One/ 100,000
(50,000 in hilly/ difficult/
tribal area)
One/ 500,000
(250,000 in hilly/
difficult/ tribal area)
TB Health Visitors (TBHV),
DOT Provider
(MPW, NGO, PP, ASHA,
Community Volunteers)
Medical Officer, paramedical staff
And Laboratory Technician (20-50%)
Medical officer-TB Control,
Senior Treatment supervisor(STS),
Senior TB Laboratory Supervisor(STLS)
District Health Services
District TB Centre
Tuberculosis Unit
Microscopy Centre
DOT Centre
Nodal point for TB
control
Structure of RNTCP at district levels
Chief Medical Officer and
other supporting staff
District Administration District Magistrate/
District Collector
DTO, MO-DTC (15%), LT, DEO,
Driver, Urban TB Coordinators,
TBHVs, Communication Facilitators
79. Unique features of RNTCP
• District TB Control Society
• Modular training
• Patient wise boxes
• Sub-district level supervisory staff (STS, STLS)
for treatment & microscopy
• Robust reporting and recording system
80. 0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
110%
120%
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009
Annualised New S+ve CDR Success rate
•Population projected from 2001 census
•Estimated no. of NSP cases - 75/100,000 population per year (based on recent ARTI report)
Annualized New Smear-Positive Case Detection Rate
and Treatment Success Rate in DOTS Areas, India, 2000-2009*
81. Impact of RNTCP
• Cure rate more than doubled compared with earlier NTP,
85% global target consistently achieved 2003 onwards
• Case detection rate is more than 70%
• Case fatality reduced from 29% to 4% in NSP cases, and
deaths due to TB from 500,000 to <330,000 a year
• Over 11 million patients initiated on DOTS, and over 2
million additional lives saved
Editor's Notes
Divide into two slides
However, in terms of absolute numbers, India accounts for one fifth of the global Tuberculosis burden. Every year 1.9 million people in India develop tuberculosis (TB), of which 0.8 million are sputum positive cases that are infectious. Tuberculosis is unique among the main disease killers of the developing world in that it afflicts nearly all age groups. Tuberculosis has devastating social costs as well. This continued burden of disease is particularly tragic because TB is nearly 100% curable. Untreated patients can infect 10-15 persons each year; poorly treated patients develop drug resistant and potentially incurable TB.
This slide begins a series of 8 slides taken from the WHO publication:
[Reference: Guidelines for the programmatic management of drug-resistant tuberculosis (WHO/HTM/TB/2006.361)]
Three strategic options for treatment of MDR-TB are currently recommended by WHO:
1. Standardized regimens are based on information about the drugs used in the country in the past and the results of drug-resistance testing within the population. This information can be used to develop a regimen for use in all previously treated patients or other patients in whom resistance is strongly suggested.
2. The composition of empiric regimens is determined individually based on knowledge of the drugs used previously and local resistance patterns.
3. Individualized treatment regimens are based on the history of drugs used previously and the results of drug susceptibility testing. It should be noted that because of the delay in obtaining second-line drug-susceptibility test results, even when such testing is available, most patients are begun on either a standardized or an empiric regimen.
The choice among these 3 approaches is largely determined by the 3 factors listed. [Review content of slide]
It should be noted that 2nd-line drug susceptibility testing is not well standardized and that results even between experienced laboratories may vary. Consequently, quality control for these laboratories is very important for the test results to be valid.
Step by step, building an individualized MDR regimen:
Individualized treatment regimens (based on DST profiles and previous drug history of individual patients, or on local patterns of drug utilization) have the advantage of avoiding toxic and expensive drugs to which the MDR strain is resistant.
However, an individualized approach requires access to substantial human, financial and technical (laboratory) capacity.
The first step in building a MDR-TB regimen is to identify any 1st-line drugs which are proven or likely susceptible. These generally should be used if the organism is susceptible, even if they have been used previously as part of a failed treatment regimen.
Next a fluoroquinolone, which will likely be the most important and active drug in the regimen, should be added if one is available. When a fluoroquinolone is not included in the treatment regimen the likelihood of a good outcome is significantly less. The high mortality of XDR-TB is especially related to resistance to fluoroquinolones. Moxifloxacin is regarded by many to be the most active fluoroquinolone (and ciprofloxacin no longer recommended).
Finally an injectable agent should be added. Any of these agents is generally considered equally efficacious but slight differences in toxicity profiles exist. Because the incidence of streptomycin resistance is &gt;10% in many areas of the world, it should only be used if there is documented sensitivity.
This is also the sequence by which an empiric MDR-TB treatment regimen is built, except that drug-susceptibility testing is not available.
After incorporation of drugs in Step 1, the next step is to add one or more of the oral 2nd-line drugs to create a regimen of at least four and preferably five to six drugs.
In designing the regimen, co-morbid conditions must be taken into account. For example, cycloserine should be avoided in patients with seizures or serious underlying psychiatric disorders and ethionamide should not be given to patients with serious underlying liver disease.
[Note: Prothionamide and terizadone are additional oral 2nd-line drugs that may be available in some countries.]
If an acceptable regimen cannot be built from drugs available in Step 1 and 2, the addition of 3rd-line agents is considered.
The drug that is thought to be most helpful from this group is linezolid.
Remember, consult an expert for the management of all drug-resistant cases, but especially those requiring the use of drugs in Step 3.
[Interactive option: The development of individualized regimens is dependant on the availability of drug-susceptibility testing. Ask participants their experience with these tests, their availability or any problems with their use. Ask if there are any questions in regards to how these same steps would be used to develop an empiric regimen for a patient without DST. Ask if they can anticipate how these steps may be affected by the presence of XDR-TB (information on following slides).]
With XDR-TB there is likely to be no drug listed on this Step 1 slide that could be assumed to be effective. Such patients commonly have resistance to all first line drugs.
There is a high degree of cross resistance between amikacin and kanamycin. In some isolates there is also cross resistance with capreomycin.
Commonly in patients with XDR-TB, building a regimen begins with Step 2 using the oral 2nd-line drugs to create a regimen of at least four and preferably five to six drugs.
[Note: Prothionamide and terizadone are additional oral 2nd-line drugs that may be available in some countries.]
For XDR-TB, additional 3rd-line agents will often be needed to augment the regimen.
Again, the drug that is thought to be most helpful from this group is linezolid. High costs for this drug can be a prohibitory obstacle for many programs and patients.
Expert consultation should be obtained for help with the complex and lengthy management of XDR cases.
When initiating treatment for MDR/XDR-TB, one should:
[Review content of slide]
Adverse effects are a major limitation in using 2nd-line drugs. To use the drugs safely and effectively there must be laboratory services available.
Experience and skill are needed in guiding a patient through what may be a very difficult treatment program. Treatment using 2nd-line drugs is sufficiently complicated that it is best undertaken by a person who has specific training in management of MDR-TB.
And again as noted before, DOT is an essential component in the management of MDR/XDR-TB to help ensure adherence, monitor for adverse effects, and support the patient through a long and often difficult treatment course.
Management Principles:
To prevent the spread of MDR/XDR-TB, patients should be isolated until 3 consecutive sputa AFB smears (or documented culture conversion in some circumstances) are negative and there has been a good response to treatment.
Close supervision is essential when initiating treatment. Drug toxicities can occur frequently.
Severe anorexia and nausea is very common with ethionamide, diarrhea with PAS, and altered mental status with cycloserine. These 3 drugs, in particular should be increased to full dose slowly over a course of a week to minimize side effects.
Toxicity monitoring should be tailored to each drug used (e.g. hypothyroidism can occur with both ethionamide and PAS; renal dysfunction and ototoxicity with all injectable agents).
It is essential that the provider understands the side effects of each drug used.
[A good resource for toxicity and its monitoring can be found in the Drug-Resistant Tuberculosis, A Survival Guide for Clinicians 2nd edition. http://www.nationaltbcenter.ucsf.edu/drtb/]
Patient-centered DOT ensures adherence to treatment; addresses social issues that creates barriers to treatment and enables effective clinical monitoring.
Good documentation with case management tools to follow serial changes in drugs, bacteriology, radiographic findings, and toxicities helps minimize errors. These tools also help to keep track of the patient’s progress (or lack of progress) during treatment.
Last but not least, adequate nutritional status and management of other medical conditions are essential in the recovery of patients with MDR-TB.
As resources permit, an optimal monitoring plan would include:
Monthly collection of sputum specimens until smears and cultures have converted
Additional sputum specimen collection at the end of treatment to document cure
Periodic chest radiographs during treatment and at the end of treatment (provides further evidence of the effectiveness of treatment)
Periodic sputum collection and clinical evaluation for a period 2 years after treatment ends to detect possible relapse
Formattiing required..TURN 450 INTO PERCENTAGE
Explanatory notes (brief and carefully written)
Treatment success has recently exceeded the global target of 85%
Case Detection in DOTS areas has recently attained global target of 70%
Add slide of graphs (differential mortality) with reference