PULMONOLOGIST'S GUIDE TO TUBERCULOSIS CARE

PULMONARY TUBERCULOSIS

TB is a contagious disease caused by Mycobacterium Tuberculosis. When it affects lungs, which is most common, it is called Pulmonary Tuberculosis (PTB). But it can affect any part of the body like bone, spine, brain, lymphnodes, kidney, uterus, testis and intestines, when it is called Extra Pulmonary Tuberculosis (EPTB).

WHAT IS ACTIVE TB AND WHAT IS LTBI?

The importance of Pulmonary TB is that it is contagious and spreads from person to person through air. When a person with PTB coughs, sneezes or speaks , TB Bacteria will release into the air. People near by can inhale the bacteria and develop TB infection. However, only 5 to 10 % of people who get infected in such a manner will develop the ACTIVE disease. In the remaining 90 to 95 % of infected people, the bacteria can be contained , without progressing to active disease because of 'good immunity'. These bacteria may remain dormant or viable in various organs of the body like lungs, kidney, bone, genital tract, brain etc forever. This is called Latent TB Infection (LTBI) . 5 to 10 % of these of LTBI people develop ACTIVE TB disease sometime in their lifetime when their immunity weakens due to malnutrition, diabetes, HIV infection, kidney disease, advanced age and immunosupressant therapy.

HOW COMMON IS LTBI?

LTBI: 1/3 rd the world population are infected with TB bacilli. These individuals have no symptoms and do not spread infection. But can develop ACTIVE TB disease later in life.

MANIFESTATIONS OF ACTIVE TB:

The symptoms of active TB depend on the organ affected by TB.

Signs and Symptoms of PULMOANARY TB (PTB) are:

Chronic cough lasting for 3+ weeks.

Coghing up blood in sputum.

Chest pain.

Fever, night sweats, fatigue, weakness.

Loss of weight and Loss of appetite .

When TB affects organs of body other than lungs ,it is called EXTRA PULMONARY TB (EPTB).

Signs and symptoms of EPTB are:

1. LYMPHNODE TB:

   Enlarged glands appear as swellings in the neck, axilla etc. They may grow into cold abscesses and may rupture causing caseous pus to leak.

2. KIDNEY TB:

   Painful urination, blood in urine , fever and swelling in the loins.

3. GENITAL TB:

   Women affected with Genital TB ( Reproductive organs like ovaries, fallopian tubes, uterus are involved ) will present with INFERTILITY (inablity to achieve pregnancy), tubo ovarian masses and menstrual disturbances. In India 1/3rd of the tubal block diseases are due to TB.

4. BONE AND JOINT TB:

   Pain, swelling and restricted movements of the joints are the manifestations. Weight bearing joints like hip joint and knee joints are most commonly involved.

5. CENTRL NERVOUS SYSTEM TB ( CNS TB ):

   Brain and spinal cord are involved. Headache, irritability, vomitings, confusion, neck stiffness and convulsions (fits) , high grade fever are the symptoms.

6. SKIN TB ( CUTANEOUS TB)

   Rashes, nodules, ulcers, plaques over the skin.

7. IN CHILDREN :

   In infants and young children , the presentation is mostly with failure to thrive, persistent fever, night sweats, swollen glands, anemia, irritability and seizures.

COMPLICATIONS OF UNDIAGNOSED AND UNTREATED TB DISEASE:

When PULMONARY or EXTRA PULMONARY TB is not diagnosed or treated early, the disease will progress leading to complications.

In PULMONARY TB:

The damage to lungs causes scarring, cavities, bronchiectasis, COPD, hemoptysis, spread to other parts of the body, diminished lung functions , Drug Ressistant TB (DRTB).

In EXTRA PULMONARY TB:

1. LYMPH NODE TB : Cold abscesses, chronic discharging sinuses or ulcers and scarring.

2. SPINAL TB: Gibbus deformity of spine, Psoas abscess, Paraplegia. (Paralysis of both lower limbs), Loss of bladder and bowel control.

3. BONE AND JOINT TB: Joint destruction and deformity, reduced movements of the affected joints.

4. CNS TB: Hydrocephalus ( swelling of brain due to obstruction), Cranial nerve palsies, loss of conciousness, stroke, seizures , brain damage.

5. GENITOURINARY TB: Destruction of kidney resulting in chronic kidney disease, obstruction in ureters leading to hydronephrosis ( swelling of kidney) , small shrunken kidney, shrunken and fibrotic bladder resulting in Thimble bladder, blockade of fallopian tubes in females leading to infertility; obstruction of vas deferens, ejaculatory dysfunction and scrotal sinuses in males.

HOW DOES A PULMONOLOGIST / TB SPECIALIST ARRIVE AT DIAGNOSIS?

1. SPUTUM MICROSCOPY / FLOUROSCENT MICROSCOPY: Its a cheap, rapid, widely available test. The test results are positive when at least 10,000 bacilli are present in one ml of sputum.

2. MOLECULAR DIAGNOSTIC TESTS: In these tests,the genetic material of MTB eg.DNA is detected. These tests have the advantage of giving positive results even if a single bacillus is present in sputum. In addition they can detect resistance mutations to RIFAMPICIN which is the cornerstone drug in treatment of TB.

Eg: CBNAAT/ GeneXpert MTB/RIF

TRUE NAT Xpert MTB

LPA ( Line Probe Assay)

3. SPTUM CULTURE FOR MTB: Gold standard test for detecting MTB.

Eg. LJ Medium and Middlebrook media

Liquid media like MGIT,MODS etc for rapid results

4. CHEST X RAY AND CT SCAN: help by observing radiological featres suggestive of TB.

5. BRONCHOSOPY: If sputum microscopy or CBNAAT tests are negative,but TB is strongly suspected, bronchoscopy will be done by a TB specialist or Chest physician for collection of lung secretions as samples or biopsies throgh Bronchial Washings / BAL / Biopsy.

OTHER TESTS WHICH HELP IN DIAGNOSIS OF EXTRAPULMONARY TB:

(Depending on Site of TB disease)

Pleural Fluid analysis testing by CBNAAT, Cultures, Pleural biopsy in PLEURAL TB.

Lymph Node aspirate/ Biopsy for MTB / HPE, in LYMPHNODE TB.

CSF analysis and testing for CBNAAT and Cultures in CNS TB

Hysteroscopy, Laparoscopy and Endometrial biopsy, PCR tests in GENITAL TB.

TESTS FOR LATENT TB INFECTION ( LTBI )

TUBERCULIN SENSITIVITY TEST ( TST OR MANTOUX TEST)

INTERFERON GAMMA RELEASE ASSAY (IGRA)

THE PRINCIPLES OF TREATMENT OF TB:

TB is generally considered curable with early and appropriate treatment as advised by a TB specialist. Incomplete, irregular or inconsistent treatment can lead to Drug Resistant TB (DRTB) which is more challenging to treat.

TREATMENT OF DRUG SENSITIVE TB:

Standard TB treatment consists of combination of First Line anti TB drugs, which are ISONIAZIDE,RIFAMPICIN, PYRAZINAMIDE and ETHAMBUTOL. These are given for 2 months (INTIAL INTENSIVE PHASE) ,followed by 4 months of ETHAMBUTOL, ISONIAZIDE AND RIFAMPICIN ( CONTINUOUS PHASE) .

Total duration of 6-9 months.

TREATMENT OF DRUG RESISTANT TB:(MDRTB/XDRTB):

Treatment is more complicated, because of longer duration , toxicities, difficulties in ensuring patient's adherence and higher treatment costs..

Treatment involves using Second Line drugs like, LINEZOLID,CLOFAZAMINE,MOXIFLOXACIN,BEDAQUILINE,ETHIONAMIDE etc.

Duration of treatment varies from 9 - 20 months or longer.

In selected cases BPaLM regimen is the first choice of treatment:

It consists of BEDAQQUILINE,PRETOMANID,LINEZOLID ,MOXIFLOXACIN for 6 months.

The war against TB begins with awareness and ends with cure.

Dont ignore a persistant cough - consult a TB specialist, follow the treatment and complete the journey to recovery.

"Together, we can make India TB - free".

PULMONARY TUBERCULOSIS SHOWING CAVITIES AND NODULES

NECROSIS AND DISCHARGING SINUSES IN LYMPHNODE TB IN NECK

TB ABSCESS SURROUNDED BY EDEMA IN BRAIN

NECROSIS AND GRANNULOMAS IN KIDNEY TB

FEMALE GENITAL TB WITH ABSCESSES, GRANNULOMAS AND TUBAL BLOCK