Download tberculosis - Peshawar Medical College

TUBERCULOSIS
Diagnosis & treatment
Dr. Fazli Wahab
FCPS(Med), FCPS(Pulmonology)
Assisstant Prof Peshawar Medical College
Diagnostic Tools

Microscopy
◦ AFB smear
◦ Histology

AFB Culture

Radiology

Tuberculin skin test

Serological Tests
AFB smear

Rapid and inexpensive
Granuloma
Mycobacterial Culture

Definitive diagnosis

Growth detected after 4–8 weeks.
Radiographic Procedures

The "classic" picture is that of upper-lobe
disease with infiltrates and cavities,
X-ray chest appearance can be any of the following
Infiltration
Cavitations
Fibrosis with traction
Enlargement of hilar and mediastinal lymph node
 Pleural effusion/empyema
Nodular/ Miliary shadows
Mantoux Tuberculin Test (MT)/ Tuberculin
Skin Test (TST)

Test TB infection in adults and children
Patient status
Healthy individuals with
no exposure history
Positive
Result
>15mm
Healthy individuals with
exposure history or risk
factors
>10mm
HIV +ve
>5mm
Serological Tests

Not routinely used

Polymerase Chain Reaction (PCR)

Interferon Gamma release assays (IGRS)

Enzyme Assays & Chromatographic assays:
◦
◦
◦
◦
Unreliable & Ineffective methods
No role in diagnosis in any form of TB
Mycodot assay
ICT TB
Treatment

Two aims
◦ Interrupt transmission
◦ Prevent morbidity and death.
Anti-tuberculosis Drugs
1ST LINE DRUGS:
•
Isoniazid (H)
•
Rifampicin (R)
•
Pyrazinamide (Z)
•
Ethambutol (E)
•
Streptomycin (S)
1st line ATT
Mode of Action
Daily
Dose (mg/kg)
Isoniazid (H)
Bactericidal
5
(4-6)
Rifampicin (R)
Bactericidal
10
(8-12)
Pyrazinamide (Z) Bactericidal
25
(20-30)
Streptomycin (S)
Bactericidal
15
(12-18)
Ethambutol (E)
Bacteriostatic
15
(15-20)
Regimens
Standard short course regimens 6-8
months.

An initial, intensive or bactericidal, phase
and

A continuation, or sterilizing, phase.
DOTS

DOTS (directly observed treatment, short-course),
the WHO-recommended TB control strategy.
New Cases
•Sputum smear positive pulmonary TB
•Sputum smear negative pulmonary TB
•Extra-pulmonary tuberculosis
WHO Category I:
•New SS +VE Pulmonary TB
•Severe Extra-Pulmonary
•Severe SS –VE Pulmonary TB
WHO Category III:
New SS-VE Pulmonary TB
Extra-Pulmonary (less severe)
Initial Intensive Phase
HRZE : 2 Months
Continuation Phase
HR: 4months OR HE: 6 Months
RE-TREATMENT CASES/ WHOCategory II:
•Relapse
•Treatment Failures
•Smear positive patients who have taken ATT for more than one month and
defaulted
INITIAL INTENSIVE PHASE (3months)
HRZES: 2MONTHS
Then HRZE:1 Month
CONTINUATION PHASE
HRE: 5 Months
No Treatment is better than Poor Treatment

Drug-resistant TB is caused by:
◦ Inconsistent or partial treatment, when patients do not take all
their medicines regularly for the required period.
◦ Doctors and health workers prescribe the wrong treatment
regimens, or because
◦ The drug supply is unreliable.

The ultimate result is the multidrug-resistant
TB (MDR-TB) or extensively-drug resistant TB
(XDR-TB)

In MDR-TB the Mycobacterium Tuberculosis is
resistant to Rifampacin and INH with or
without resistance to other 1st ATT.

Treatment is difficult and expensive.
Prevention

The best way to prevent tuberculosis is
to Treat.

Additional strategies include
◦ BCG vaccination and
◦ Treatment of persons with latent tuberculosis
infection who are at high risk of developing
active disease.
ATT in Special situations

Pregnancy

Infants of T.B. mothers & Breast Feeding

Women on O.C.P

Renal Impairment

ATT Induced Hepatitis

HIV - Infected or AIDS
Pregnancy

H, R, Z, E : Safe
Streptomycin: Ototoxic
 May cause deafness in babies
 Contraindicated

Infants of T.B. mothers & Breast Feeding

Mothers must continue A.T.T during
feeding

Child should not be separated

Mother should cover her mouth during
cough particularly if smear +ve

INH prophylaxis : 5 mg/Kg 2 months
Infants of T.B. mothers & Breast Feeding


Do T.T:
If –ve
◦ Stop INH, give BCG

If +ve
◦ Continue INH 4 months
◦ Then BCG

Do not give BCG while on INH
◦ INH resistant BCG

Rifampicin + INH – 3 months
Women on O.C.P

Rifampicin:
◦ Hepatic enzyme inducer
◦ O.C.P may become ineffective
Renal Impairment

General principle:
◦ Standard chemotherapy
◦ Standard duration
◦ Dose interval modification

Rifampicin and INH
◦ Safe and use normal dose

Pyrazinamide
◦ Needs dose interval adjustment
Renal Impairment

Ethambutol
◦ Nephrotoxic , Renal excretion - 80% unchanged
◦ Ocular toxicity – dose dependent
◦ Serum monitoring required

Amino glycosides – Streptomycin
◦ Nephrotoxic, renal excretion- 80% unchanged
◦ Needs dose interval adjustment in all stages

New recomandations
◦ Avoid Aminoglycosides
ATT Induced Hepatitis

Usually present early but may present any
time

Mild / transient derangement in LFTs is
normal (15 – 20 %)

TYPES:
◦ Hepatocellular:
◦ Cholestatic
◦ Mixed
ATT Induced Hepatitis
RISK FACTOR










Age >35 years
Female sex
Oriental race (EAST ASIAN)
Pre-existing liver disease
Extensive tuberculosis
High alcohol consumption
Malnutrition and hypo Albuminemia
Other hepatotoxic drugs
Slow Acetylator status
High dosage in relation to body weight
Management

↑ ALT/AST (< Twice normal)
◦ Continue ATT
◦ Check after 2 weeks

↑ ALT/AST (>Twice normal)
◦ Continue ATT
◦ Check LFTs weekly for 2 weeks
◦ Then every 2 weeks until normal
Management

↑ ALT/AST (>Thrice normal) + Symptoms
◦ Anorexia, Nausea, Vomiting, Abdominal Pain , Jaundice
◦ STOP ATT

↑ ALT/AST (>5 time normal) OR ↑ Bilirubin
◦ Even If Patient Asymptomatic
◦ Stop ATT

If patient is smear –ve / Clinically stable
◦ Wait until LFTs are normal
◦ No need for alternate drugs

If patient is smear +ve / Clinically unstable
◦ Start Ethambutol, Streptomycin and one of the reserve
drugs until LFT‘s are normal
◦ Continue safe drugs until LFTs are normal
Management

When LFT’s are normal
◦ Reintroduce ATT to detect offending drugs
◦ Start with least hepatotoxic one by one


INH > RIF > PZA
If no reaction
◦ Continue ATT
◦ Stop alternate drugs

If reaction has developed
◦ Stop offending drug
◦ Continue remaining drugs

Ensure adequate regimen and duration
HIV - Infected or AIDS

Standard regimen – usually good response
◦ Drug reactions more common
◦ Thiacetazone should be avoided
◦ Prolonged treatment
Thanks