Reading Time: 7 Minutes | Quiz Included
Tuberculosis has been killing humans for thousands of years. Ancient Egyptian mummies show signs of TB in their spines. Today, India alone accounts for about 26% of all TB cases worldwide. Yet this is one disease that is completely curable if the patient takes the right medicines for the right duration without stopping in between.
For NORCET, RRB, ESIC, and State PSC exams, TB is asked every single year. Examiners focus heavily on DOTS therapy drug names, drug side effects, and nursing management. Once you understand the logic behind why each drug is used and what it damages, every TB question becomes straightforward.
Table of Contents
1. What is Tuberculosis and How Does It Spread?
The Causative Organism
Tuberculosis is caused by a bacterium called Mycobacterium tuberculosis. It is also called Koch's bacillus, named after Robert Koch who discovered it in 1882. This bacterium is unique because it has a thick waxy coat made of mycolic acid. This coat makes it resistant to most antibiotics and is why TB treatment takes 6 months instead of a few days.
The bacterium is an aerobic organism - it needs oxygen to survive. This is exactly why it loves the upper lobes of the lungs, where oxygen concentration is highest. When the bacteria settle there, they trigger the immune system to wall them off in a small mass called a granuloma.
How TB Spreads
TB spreads through the air by droplet nuclei - tiny invisible particles released when an infected person coughs, sneezes, speaks, or sings. These particles are so small they can float in the air for hours. A single cough can release up to 3000 infectious droplet nuclei.
TB does NOT spread through sharing food, water, utensils, or touching an infected person. It is purely an airborne infection. This is why the most important nursing intervention is airborne precautions - not droplet precautions.
2. Types of TB and Diagnosis
Primary vs Post-Primary TB
| Feature | Primary TB | Post-Primary (Secondary) TB |
|---|---|---|
| When It Occurs | First time the body encounters TB bacteria | Reactivation of old infection or reinfection |
| Who Gets It | Children, immunocompromised people | Adults, especially those with weak immunity |
| Location in Lung | Middle and lower lobes (Ghon focus) | Upper lobes (high oxygen area) |
| Ghon Complex | Ghon focus + hilar lymph node = Ghon complex | No Ghon complex. Cavitation is common. |
| Symptoms | Often mild or no symptoms | Classic TB symptoms: cough, hemoptysis, night sweats |
Pulmonary vs Extrapulmonary TB
| Type | Site Affected | Special Name |
|---|---|---|
| Pulmonary TB | Lungs (most common, 80%) | Most infectious form |
| TB Meningitis | Brain and meninges | Most dangerous form |
| Pott's Disease | Spine (vertebrae) | TB Spondylitis |
| Miliary TB | Entire body via bloodstream | Disseminated TB - millet seed pattern on X-ray |
| TB Lymphadenitis | Lymph nodes (especially cervical) | Scrofula |
| TB Pericarditis | Pericardium (heart covering) | Can cause constrictive pericarditis |
Diagnosis of TB
The most definitive diagnosis of TB is sputum culture and sensitivity, but it takes 4-8 weeks. For quick diagnosis, sputum smear microscopy (AFB stain) is used. Three early morning sputum samples are collected on three consecutive days.
The Mantoux test (Tuberculin Skin Test) is used for screening. PPD (Purified Protein Derivative) is injected intradermally in the forearm. Read after 48-72 hours. Induration of 10 mm or more is considered positive in general population. For immunocompromised or HIV patients, even 5 mm induration is positive.
3. DOTS Therapy - Drug Names and Treatment Phases
What is DOTS?
DOTS stands for Directly Observed Treatment Short Course. It is the WHO-recommended strategy for TB treatment. A health worker physically watches the patient swallow every single dose of medicine. This prevents the patient from skipping doses, which leads to drug resistance.
Standard DOTS Regimen for New TB Cases
| Phase | Duration | Drugs Used | Short Code |
|---|---|---|---|
| Intensive Phase | 2 months | Isoniazid + Rifampicin + Pyrazinamide + Ethambutol | 2HRZE |
| Continuation Phase | 4 months | Isoniazid + Rifampicin | 4HR |
| Total Duration | 6 months | All four drugs then two drugs | 2HRZE + 4HR |
Drug Side Effects - Most Exam-Tested Topic
| Drug | Short Code | Key Side Effect | Nursing Action |
|---|---|---|---|
| Isoniazid | H | Peripheral Neuropathy (tingling and numbness in hands and feet). Also hepatotoxic. | Give Pyridoxine (Vitamin B6) to prevent neuropathy. Monitor liver enzymes. |
| Rifampicin | R | Orange-red discoloration of urine, tears, sweat, and saliva. Hepatotoxic. Reduces effectiveness of oral contraceptives. | Warn patient that orange urine is harmless and expected. Advise alternative contraception. Monitor liver function. |
| Pyrazinamide | Z | Hyperuricemia (high uric acid levels causing gout-like joint pains). Hepatotoxic. | Monitor serum uric acid levels. Monitor for joint pain and swelling. Monitor liver enzymes. |
| Ethambutol | E | Optic Neuritis (inflammation of optic nerve causing blurred vision and loss of ability to distinguish red and green colors). | Baseline visual acuity test before starting. Monthly visual check. If vision changes, report immediately and stop drug. |
| Streptomycin | S | Ototoxicity (hearing loss, tinnitus, vertigo). Nephrotoxic. | Baseline hearing test. Monitor renal function. Never give in pregnancy (causes fetal hearing damage). |
Golden Points to Remember:
- Airborne Precautions for TB: TB spreads via airborne droplet nuclei, not droplets. So the nurse must wear an N95 respirator mask (not a surgical mask). The patient should be in a negative pressure isolation room with the door kept closed at all times. At least 6-12 air exchanges per hour are required in the room.
- Sputum Collection Rule: Always collect sputum early morning before eating or brushing teeth. The first morning sample has the highest concentration of bacteria. Instruct the patient to take a deep breath and cough from deep inside the lungs, not just spit saliva.
- MDR-TB (Multi Drug Resistant TB): When TB bacteria become resistant to at least Isoniazid and Rifampicin (the two most powerful first-line drugs), it is called MDR-TB. The main cause is incomplete or irregular treatment. MDR-TB requires second-line drugs for 18-24 months. Treatment is much harder, more toxic, and more expensive.
- BCG Vaccine: BCG (Bacillus Calmette-Guerin) vaccine is given at birth under the national immunization program. It protects against severe forms of childhood TB like TB meningitis and miliary TB. It does NOT fully protect against pulmonary TB in adults. BCG is given intradermally in the left deltoid region and leaves a small scar.
- Isoniazid Preventive Therapy (IPT): Given to close contacts of TB patients, HIV positive individuals, and children under 5 years who live with an active TB patient. Isoniazid 300 mg daily for 6 months is given to prevent TB from developing in exposed but not yet infected people.
4. Nursing Management and Infection Control
Airborne Isolation Precautions
The patient with active pulmonary TB must be placed in a negative pressure isolation room. Negative pressure means air flows INTO the room from the corridor, not out. This prevents contaminated air from escaping into the hospital hallway.
The nurse must wear a fitted N95 respirator every time entering the room. A regular surgical mask does not filter particles small enough to stop TB droplet nuclei. The patient should wear a surgical mask when being transported outside the room for any procedure.
Patient and Family Education
The most important education point is about treatment completion. Patients often feel better after 2-3 weeks and stop taking medicines. This is the single biggest cause of drug resistance and treatment failure. The nurse must explain clearly that feeling better does not mean cured. The bacteria are still alive and can come back stronger.
Teach the patient proper cough hygiene - cover the mouth with a tissue or elbow when coughing, never the hand. Dispose of tissues immediately in a covered bin. Wash hands frequently. Ensure good ventilation at home - open windows, let sunlight in. TB bacteria are killed by direct sunlight and fresh air.
Monitoring During Treatment
Every patient on TB treatment needs regular monitoring. Check liver function tests (ALT, AST) before starting and monthly during treatment because three drugs - Isoniazid, Rifampicin, and Pyrazinamide - are all hepatotoxic. If the patient develops jaundice, nausea, or abdominal pain, stop all drugs immediately and report to the doctor.
For Ethambutol, perform a baseline visual acuity test and color vision test before starting. Repeat monthly. Any complaint of blurred vision or inability to distinguish red from green means Ethambutol must be stopped immediately to prevent permanent vision damage.
Quick Revision Before Quiz:
- Causative organism: Mycobacterium tuberculosis (Koch's bacillus)
- Mode of spread: Airborne droplet nuclei
- Most common site: Upper lobe of lungs
- First organ affected: Lungs (Pulmonary TB = 80%)
- TB spine: Pott's disease
- TB lymph nodes: Scrofula
- Miliary TB: Millet seed pattern on X-ray
- Mantoux positive (general): 10 mm or more
- Mantoux positive (HIV): 5 mm or more
- Mantoux reading time: 48-72 hours
- DOTS full form: Directly Observed Treatment Short Course
- Intensive phase: 2 months - HRZE
- Continuation phase: 4 months - HR
- Isoniazid side effect: Peripheral Neuropathy - give Vit B6
- Rifampicin side effect: Orange urine - harmless, warn patient
- Pyrazinamide side effect: Hyperuricemia (Gout)
- Ethambutol side effect: Optic Neuritis - check vision monthly
- Streptomycin side effect: Ototoxicity - avoid in pregnancy
- MDR-TB caused by: Incomplete treatment
- Nurse wears: N95 respirator (not surgical mask)
- Room type: Negative pressure isolation room
- BCG vaccine site: Left deltoid, intradermal
- Sputum collection: Early morning, 3 consecutive days
Tuberculosis
Loading...
Quiz Result
Score: 0 / 0
Frequently Asked Questions (Tuberculosis)
Q1: Why does a nurse wear an N95 respirator and not a regular surgical mask when caring for a TB patient? Ans: TB spreads through airborne droplet nuclei which are extremely small particles (1-5 microns). A regular surgical mask has larger pores and cannot filter these tiny particles. An N95 respirator filters at least 95% of airborne particles including TB droplet nuclei. It must be properly fitted to the nurse's face with no gaps for it to work effectively. Q2: What is the most important nursing education point for a patient starting TB treatment? Ans: The most critical education point is to never stop medicines even when feeling better. Most patients feel significantly better within 2-3 weeks of starting treatment and are tempted to stop. However, the bacteria are still alive. Stopping early leads to drug resistance (MDR-TB) which is much harder and longer to treat. The patient must complete the full 6-month course without missing a single dose. Q3: A patient on TB treatment complains of tingling and numbness in both hands and feet. Which drug is responsible and what is the treatment? Ans: Peripheral neuropathy is the classic side effect of Isoniazid (H). Isoniazid interferes with Vitamin B6 (Pyridoxine) metabolism, which is essential for nerve function. The treatment is supplementation with Pyridoxine (Vitamin B6) tablets. This is why Pyridoxine is routinely given alongside Isoniazid, especially in patients who are malnourished, elderly, diabetic, or pregnant.Question for You:
A patient who has been on TB treatment for 3 weeks tells the nurse that he feels completely fine and wants to stop his medicines. He says the medicines upset his stomach and he does not think he needs them anymore. What is the most important nursing response?
A. Tell the patient it is okay to stop since he feels better.
B. Reduce the dose of medicines to reduce stomach upset.
C. Explain that stopping early causes drug resistance and the full 6-month course must be completed.
D. Immediately report to the doctor and put the patient in isolation.
Comment your answer below. Drop an A, B, C, or D and let us check your preparation level.
1 Comments
C
ReplyDelete