Friday, July 17, 2009

Epitdemiology of Tuberculosis - Kota Star District

The district health office in Kota Setar has a unit organizational chart shown below, in their chart, TB will fall under the communicable disease unit.





DIAGNOSIS OF TUBERCULOSIS

The diagnosis of tuberculosis can be done through:
- Clinical evidence
- Radiological evidence
- Bacteriological evidence
Tuberculosis can be divided in to two broad categories, pulmonary and extra-pulmonary. Pulmonary TB has more epidemiological significance as it is transmissible from person to person.
Clinical symptoms for TB include the following:
- Productive cough for more than 2 weeks
- Haemoptysis
- Fever
- Loss of appetite / loss of weight
- Night sweats
TB is more common in immunocompromised people, such as people infected with HIV or Diabetic patients. In Kota Setar, 70% of patients who were diagnosed with TB were found to be diabetics. In kota setar, every patient diagnosed with TB will have a screening test for DM, HIV and Hep B done.
The screening test initially used is a capillary blood glucose level, which if >7 mmol/l an oral glucose tolerance test will be performed.
Bacteriological diagnosis is done by sputum direct smears for acid fast bacilli. Three specimens are taken (early morning specimens). Culture of the bacterium (Lowenstein Jensen medium) takes 8 weeks. Radiometric methods such as BACTEC can give a result within 2 weeks. The mantoux test is used for the diagnosis of TB in paediatric and extra-pulmonary cases. 2 units of 0.1 ml Purified Protein Derivative is used. The results are read after 72 hours. A diameter of <10mm>10mm or more in a child or adult is considered positive (but this does not necessarily mean there is an active disease). A diameter of >15mm is significant, and may indicate a recent infection.
Radiological methods for diagnosis includes chest x-rays. Often the lesion is present in the apical and posterior segments of the upper lobe. Fibrosis and calcification in the x-rays usually suggests healed lesions.
In KKB Alor Setar, after a patient has been diagnosed with TB, a wallet (for x-rays) and a file (consisting of different forms) is opened. A treatment book is also given to the patient. Two copies; one for the clinic and the other for the patient.

CONTACT TRACING
Once a case of TB has been diagnosed, contact tracing must be performed, to find any undiagnosed cases that have contracted the infection from the person diagnosed. In Kota Setar, it is the responsibility of Mr.Nazri (PPKP) from the communicable disease division to trace all contacts of the patient.
In the Kota Setar clinic, the patient is asked who lives with him/her. The people named are then requested to come in for screening for TB. The algorithms for this are shown below:


Contact tracing for an Adult



Contact Tracing for a Child

TB NOTIFICATION

TB is a notifiable disease under the infectious disease act 342, 1988. The disease notification is done with the aid of a 10A-1 form, which has to be passed to the district health office within 1 week. The form has 15 parts, and asks for the following:
- Treatment centre (where the disease was diagnosed)
- Patient details; name, sex, weight, age, marital status, whether the person is an immigrant…
- Address of the patient with the telephone number
- Occupation
- Disease history & pre-TB diagnosis status; DM, HD, Liver disease, renal failure, steroid therapy, smoker, alcohol intake, IVD user, HIV/AIDS status, Cancer
- BCG scar and Mantoux test results
- Lab test results (staining and culturing for AFB
- HIV test results
- Histopathology test results
- Radiology and imaging test results
- Current TB episode condition
- Previous TB treatment (for recurrent cases, discontinued treatment & failed treatment)
- List of examined contacts

In klinik Kesihatan Bandar (Kota Setar), if a patient is diagnosed with TB, the patient gets screened for DM, HIV& Hep B. in this clinic, 70% of the patients with TB have Diabetes Mellitus. For DM initially the blood glucose level using a glucometre is taken, if it is >7mmol/l, an oral glucose tolerance test is performed.


INFECTION CONTROL

A patient diagnosed with TB has to be counseled on methods by which he/she can reduce the spread of the disease. Methods to be counseled on include:
- Respiratory hygiene ; cover the mouth when coughing with a tissue or handkerchief. Do not spit out sputum haphazardly. Sputum should be spit out in a sink with running water.
- Travel; any travel should be postponed until the patient is non-infectious
- Masks are provided to the patient to help reduce the spread of the disease. Ideally an N95 mask should be worn, but due to the cost of the mask it is not used in the KKB. Instead surgical masks are used.
The healthcare staff in the KKB wear surgical masks to protect them from the infection. They are supposed to get yearly x-rays to check whether they have contracted the infection (however this is not done in the clinic). They are also supposed to get mantoux tests to check for infection. This is done if any of the nurses develop any signs/symptoms of TB.
The KKB has UV ceiling lights which automatically come on at night, it automatically comes on at 7pm and switches off at 7am. This is used to destroy any bacteria present in the clinic overnight.

CLASSIFICATION OF TB

PULMONARY TB – TB involving the lung parenchyma
PULMONARY TB SMEAR POSITIVE – i) A patient with at least 2 sputum smear examinations positive for AFB
ii) A patient with one positive sputum smear examination & radiographic abnormalities consistent with active pulmonary TB.
iii) A patient with at least one positive sputum smear examination & sputum culture positive for M. tuberculosis.
PULMONARY TB SMEAR NEGATIVE – i) A patient with TB with at least 3 negative sputum smear examinations & radiographic abnormalities consistent with pulmonary TB.
ii) A patient whose initial sputum smears were negative, but sputum culture was positive for M. tuberculosis.
EXTRA PULMONARY TB – TB of organs other than the lung parenchyma. Diagnosis based on at least one culture positive specimen from an extra pulmonary site.
PULMONARY WITH EXTRA PULMONARY TB – TB involving the lung parenchyma as well as any other part of the body.

TERMS:
NEW CASE – A patient who has never had treatment for TB in the past, or has taken Anti-TB drugs for a period less than 4 weeks.
RELAPSE CASE – i) sputum positive relapse – A patient formerly declared cured of TB by a doctor after taking a full course of chemotherapy, has now become sputum smear positive.
ii) sputum negative relapse – A patient formerly declared cured of TB by a doctor after taking a full course of chemotherapy, has now developed TB based on bacteriological, histological or radiological assessment.
CHRONIC CASE – A patient who remained or became smear positive again after completing a fully supervised re-treatment regimen.
TREATMENT FAILURE – A patient who while on treatment, remained smear positive 5 months or later after commencing treatment, also a patient who was initially smear negative before starting treatment and became smear positive after the second month of treatment.
TREATMENT AFTER INTERRUPTION – A patient who interrupts anti-TB treatment for 2 months or more, and then returns to the health service with smear positive sputum.
TRANSFERRED IN CASE – A patient transferred from another centre for continuation of treatment of tuberculosis.


TREATMENT OF TB

TB can be classified into 3 categories for the purpose of treatment. These are:
Category 1 – new cases
Category 2 – Relapse, Treatment failure, Treatment after interruption
Category 3 – Chronic case
The aims of treatment are to:
- Reduce morbidity
- Prevent mortality
- Prevent relapse of TB
- To decrease transmission
- Prevent emergence of MDR TB
The first line drugs used in the treatment of TB are:
- Isoniazid (H)
- Rifampicin (R)
- Pyrazinamide (Z)
- Streptomycin (S)
- Ethambutol (E)
There are 2 phases of treatment:
- Initial / intensive – leads to rapid sputum conversion, and reduces clinical symptoms
- Continuation / maintenance – eliminates the remaining bacteria

CATEGORY 1:
- Intensive phase – 2SHRZ or 2EHRZ or 2HRZ (2 months of daily doses)
- Continuation phase – 4H2R2 or 4S2H2R2 or 4HR or 4S3H3R3

CATEGORY 2:
- Send the sputum for C&S
- Do not initiate standard treatment
- Refer to a chest physician

CATEGORY 3:
- Send the sputum for C&S
- Refer to chest physician

DRUG DOSAGES
Source: KKM PRACTICE GUIDELINES FOR THE CONTROL AND MANAGEMENT OF TUBERCULOSIS



In Kota Setar district, the treatment progress of the patient is recorded in a special card and form. The card and form come in 2 colours. A white one for extra-pulmonary or sputum negative patients and a yellow one for sputum positive patients (infectious). The card is kept by the treatment centre, while the book is kept by the patient.

DOTS (Directly Observed Treatment Shortcourse)

Malaysia has adopted the DOTS strategy for the treatment of TB. DOTS comprises the following five elements:
1) Government commitment to a national TB control programme
2) Case detection through sputum smear microscopy examination of TB suspects
3) Standardised short-course treatment regimen of six months, supervised by a trained supervisor to ensure the patient takes all the medication.
4) A regular uninterrupted supply of anti-tuberculosis drugs
5) A monitoring and reporting system to evaluate treatment outcome for each patient

Why is DOTS used? Because:
- It can produce cure rates of up to 95%
- Case detection through sputum examination is cheap, simple & reliable
- Trained healthcare workers or even community volunteers can supervise treatment.
- It does not require hospitalization or isolation
- Helps to prevent drug resistance which is 100 times more expensive to treat

In KKB, Alor Setar, the DOTS treatment supervision is done by a staff nurse. The DOTS treatment room is open from 8am – 5pm. The patients can come in anytime during the day, at their convenience. For those who have transport problems, money for transport (~ 60-70 RM / Month) can be obtained directly from the chest clinic with an application form (TB treatment allowance form 53A). In other cases, the treatment can be monitored at home, either by a healthcare person or by the family (in Kota Setar). The consensus however, is that family members cannot monitor TB treatment, it is however allowed in Kota Setar.


DEFAULTERS

Definition – a patient who has missed > 25% of the treatment doses in one month (more than 6 doses of daily treatment or 2 doses of biweekly treatment.
Steps to be taken if a patient does not show up for treatment:
1) Send the first reminder letter or phone call (in KKB phone call)
2) Send the second reminder letter or phone call (in KKB phone call)
3) If the patient does not turn up on the third day (in KKB the 10D form is filled, and passed on to the health inspector. The health inspector will make a home visit, and advice the patient to come for treatment. The patient is given 1 week to show up for treatment. If he/she does not show up for treatment, a summon is issued against the patient, and he/she will have to present themselves to a court of law.

TBIS (TB Information System)

The TBIS has been set up to fulfil the fifth element of the DOTS strategy, which is, to have a standardised recording and reporting system that allows the assessment of treatment results for each patient and of the TB control program performance overall.
The TBIS in Malaysia, consists of the forms filled and kept in the ‘National TB control program folder (TBIS 10B-1)’, as well as the electronic records entered into the e-notis & my TB databases.

TBIS 10B-1 folder: this is the main folder in which all the patient records are kept. On the cover it asks for:
- Name
- Age
- Sex
- Race
- Work
- Address
- Telephone number
- Registration number
- Treatment centre
- Health office
- Old registration number (for re-starting treatment)
The inner pages have portions to record the progress of the patient, test results (LFT’s, Renal profile, FBS, chest x-ray) and treatment details.
TBIS 10A-1 form – this is the TB notification form, which has already been discussed above
PER-PAT 301 – pathology service form – clinical information as well as tests ordered are recorded on this form.
TBIS 10C-1 and 2 – this is a form filled out for contacts who need to undergo a TB confirmation test.
TBIS 10A-4 – TB registration number slip, which contains the patients details, the treatment centre as well as the TB registration number
TBIS 10A-3 – TB case investigation details – contains the following sections:
· Patient details
· Patient background information
· Family background & financial information
· TB infection risk factors
· Patient movement (address other than current home address)
· Source and place of infection
· List of contacts
· Investigator’s details
TBIS 10J – a form to investigate deaths in TB treatment. Contains the following sections:
· Registration centre details
· Patient details
· Death details
· Decision reached by audit meeting
TBIS 10I – treatment details, including details about the intensive phase, continuation phase and a summary at the end of treatment.
TBIS 10H/10E – treatment card and treatment book respectively
In Kota setar, Mr. Nazri will receive all TBIS 10A-1 forms from all the government clinics in the district, but not from the hospitals. The information from the forms will be transferred to the e-notis online database, which is a registry for all diseases. The information from here is automatically transferred to the myTB database, which gives more detailed information, including treatment progress, defaulters, results.

No comments: