Download TUBERCULOSIS TREATMENT

TUBERCULOSIS TREATMENT
Tuberculosis (TB) is caused by bacteria (Mycobacterium tuberculosis) that most often affect the
lungs (Pulmonary TB). Tuberculosis is curable and preventable. It is spread from person to person
through the air. When people with pulmonary TB cough, sneeze or spit, they propel the TB germs
into the air. A person needs to inhale only a few of these germs to become infected. About onequarter of the world's population has a TB infection, which means people have been infected by
TB bacteria but are not (yet) ill with the disease and cannot transmit it. People infected with TB
bacteria have a 5–10% lifetime risk of falling ill with TB. Those with compromised immune
systems, such as people living with HIV, malnutrition or diabetes, or people who use tobacco,
have a higher risk of falling ill. When a person develops active TB disease, the symptoms (such as
cough, fever, night sweats, or weight loss) may be mild for many months. This can lead to delays
in seeking care.
Anti-TB chemotherapy is the most important intervention for the control of TB in any population.
Chemotherapy kills Mycobacteria tuberculosis bacilli from an infectious patient and thus stopping
transmission in the community. Most patients with smear positive TB on treatment become
noninfectious within 5 days of commencing effective treatment. For rational and effective
management of patients with TB disease, it is very important that every patient is categorized
correctly, before chemotherapy is started.
Cases of TB are classified according to the:
 The level of certainty
 Anatomical site of disease
 Bacteriological results (including drug resistance)
 History of previous treatment;
 HIV status of the patient.
Below is the table of the first line drugs used for the treatment of TB and their mode of action
in Namibia:
Generic name
Rifampicin
Isoniazid
Pyrazinamide
Streptomycin
Ethambutol
Mode of action
Bactericidal
Bactericidal
Bactericidal
Bactericidal
Bacteriostatic
Abbreviation
R
H
Z
S
E
TB treatment in adults
1.1 Standard Treatment regimens for defined patient groups
Namibia maintains WHO recommended standardized TB treatment regimens. Standardized
treatment means that all patients in a defined group receive the same treatment regimen. For
assigning standard regimens, patients are grouped by the same patient registration groups used
for recording and reporting, which differentiate new patients from those who have had prior
treatment. Registration groups for previously treated patients are based on the outcome of their
prior treatment course: failure, relapse and default and other
Recommended regimens for different patient registration groups are shown in tables below.
Previous guidelines used to refer to category 1, category 2 and second line regimens. These new
guidelines now use ―new patient regimen‖ (standard regimen for new TB patients),
―retreatment regimen with 1st line medicines‖ (standard regimen for previously treated
patients) and ―DR TB treatment regimens‖
New patients regimen – 2RHZE/4RHE
Initial phase of 2 months of RHZE daily, followed by continuation phase of 4 months of RHE
daily (total 6 months)
Retreatment regimen with 1st line medicines – 2RHZES/1RHZE/5RHE
Initial phase of 2 months of RHZES daily, followed by 1 month of RHZE daily, followed by
continuation phase of 5 months of RHE daily (total 8 months)
1.2 Treatment dosages by weight categories
1.2.1 Fixed dose combinations
The WHO continues to recommend the use of fixed-dose combinations (FDCs) as they are
thought to prevent acquisition of drug resistance due to inadequate therapy, which may occur
with separate (―loose‖) medicines. Due to the large number of tablets used in the treatment
regimens of TB, fixed-dose combination (FDC) tablets, each combining two or more anti-TB drugs,
have been manufactured since the 1980s [5] to simplify TB therapy and facilitate physician and
patient compliance with treatment recommendations [6]. These FDC tablets also prevent
inadvertent immunotherapy, which may occur because of physician error in prescription,
inadequate regimens or patient error in selectively taking only one drug. In addition, dealing with
one combined formulation that contains all essential drugs simplifies drug procurement, storage
and distribution, and may consequently reduce drug supply management errors and cost.
Below is a table followed to treat TB based on the fixed dose combination in Namibia:
ADULTS
Initial phase
Body weight in kg
Continuation phase
30-37
38-54
2 months
4 months
[RHZE]
[RHE]
[R150/H75/Z400/E275]
[R150/H75/E275]
Number of tablets
Number of tablets
Use pediatric FDCs (R60/H30/Z150; R60/H30) with
Ethambutol or single dose formulations calculated per drug by
body weight
2
2
3
3
55-74
4
4
75 and over
5
5
29 and below
Treatment of TB in children
Many children may be treated as outpatients; however children with severe disease should be
hospitalized. As with adults, the choice of TB treatment regimen in a child is determined by
whether the child has new TB, previously treated TB, or DR TB, irrespective of HIV status. TB
treatment in children should be given daily (7 days per week) during the intensive and
continuation phases of therapy. Response to TB treatment in even young and
immunocompromised children is generally good and swift. Below is a table that summarizes the
treatment for TB in children:
1.1 Standard first line treatment regimens
The standard regimens for new patients (new patient regimen-previously called ―Category I‖)
and for previously treated patients (retreatment regimen with FLDs-previously called ―Category
II‖) is the same for children as for adults. Exceptions to the 6 month regimen for new patients are
the treatment of TB meningitis and osteo-articular (bones and joints including spinal) TB, both of
which are treated for a longer duration. Table below summarizes the anti-TB treatment regimens
for children. Consultation with the CCRC and other specialists is recommended for any queries
regarding complicated cases.
Indication for treatment for PTB
Regimen
Standard regimen for new patients (new 2HRZE / 4HRE
patient regimen)
Standard regimen for previously treated 2HRZES / 1HRZE / 5HRE
patients (retreatment
regimen with first line medicines)
TB meningitis and osteo-articular TB
2HRZE / 10HRE
1.2 Recommended dosages
Current evidence shows that serum levels for all four oral first line anti-TB medications are lower
in children compared to adults when given at standard doses. For this reason, in 2010 WHO
revised daily dosage recommendations for children less than 12 years old as shown in Table
below.
Medicine
Recommended daily
dose
Daily dosage range in mg/kg
(maximum)
Isoniazid (H)
10 mg/kg
10-15 (300 mg)
Rifampicin (R)
15 mg/kg
10-20 (600 mg)
Pyrazinamide (Z)
35 mg/kg
30-40 (2000 mg)
Ethambutol (E)
Streptomycin (S)
15-25 (1200 mg)
20 mg/kg
15 mg/kg
12-18 (1000mg)