Tuberculosis: Pathophysiology, Diagnosis, RIPE Therapy, and Nursing Care

Tuberculosis (TB) is a high-yield NCLEX topic because it combines infection control, multi-drug therapy with distinctive side effects, and nursing priorities around airborne isolation. This guide reviews the disease process, diagnostics, the RIPE regimen, and the key teaching points students must master.

What Is Tuberculosis?

• TB is an infectious disease caused by Mycobacterium tuberculosis.
• It primarily affects the lungs but can spread to other organs (extrapulmonary TB).
• Spread occurs through airborne droplet nuclei released when an infected person coughs, sneezes, or speaks.
• Despite being preventable and curable, TB remains a leading cause of death worldwide.

Transmission and Pathophysiology

• TB is transmitted via airborne droplet nuclei that can remain suspended in the air.
• Inhaled bacteria reach the alveoli, where they are engulfed by macrophages.
• In most exposures, the immune system contains the infection, resulting in latent TB.
• In active TB, bacteria multiply and cause tissue destruction with cavity formation.

Latent vs. Active TB

Risk Factors

• Close contact with someone who has active TB.
• HIV is the strongest risk factor for progression from latent to active TB.
• Immunocompromised states: chemotherapy, chronic steroid use.
• Substance abuse, homelessness, incarceration, and recent immigration from high-prevalence countries.

Clinical Presentation

• Persistent cough lasting more than 3 weeks is the most common symptom.
• Sputum may be mucoid, purulent, or bloody (hemoptysis).
• Fever is usually low-grade, occurring in the afternoon or evening.
• Night sweats may soak bedding.
• Unexplained weight loss, anorexia, fatigue, and malaise are common.

Mnemonic — "WEIGHT": Weight loss, Evening fever, Ill health, Night sweats, Gasping cough, Tuberculosis.

Diagnostic Tests

PPD Interpretation

• ≥ 5 mm is positive in HIV-positive patients, recent close contacts, and those with chest X-ray changes consistent with prior TB.
• ≥ 10 mm is positive in recent immigrants, IV drug users, healthcare workers, and children under 4.
• ≥ 15 mm is positive in persons with no known risk factors.

Treatment: The RIPE Regimen

Mnemonic — "RIPE": Rifampin, Isoniazid, Pyrazinamide, Ethambutol.

Standard Treatment Courses

• Active TB: 2 months of RIPE, followed by 4 months of Rifampin + Isoniazid.
• Latent TB: 3 to 9 months of isoniazid or rifampin.
• Directly Observed Therapy (DOT) is recommended to ensure adherence.

Drug Side Effects and Monitoring

• Rifampin: orange-red discoloration of urine, tears, and sweat — harmless but reassure patient; stains contact lenses.
• Isoniazid: peripheral neuropathy — give pyridoxine (vitamin B6) daily.
• Ethambutol: optic neuritis — test visual acuity and color discrimination monthly.
• All RIPE drugs can cause hepatotoxicity — monitor LFTs and teach patients to report jaundice, dark urine, or abdominal pain.

Infection Control

• Patients with suspected or confirmed active TB require airborne isolation.
• Place patient in a negative pressure room with the door closed.
• Healthcare workers must wear an N95 respirator when entering the room.
• Patient should wear a surgical mask when leaving the room.
• Continue isolation until three negative sputum smears are obtained.
• Patients are generally considered non-infectious after 2 to 3 weeks of effective treatment.

Nursing Care

Assessment

• Monitor respiratory rate, depth, and breath sounds.
• Assess for cough, sputum production, and hemoptysis.
• Monitor for fever, night sweats, and weight loss.
• Assess for medication side effects: vision changes, jaundice, neuropathy.

Interventions

• Initiate airborne precautions immediately for suspected TB.
• Wear N95 respirator and place patient in a negative pressure room.
• Administer medications on time and document adherence.
• Provide vitamin B6 with isoniazid.
• Monitor LFTs and teach signs of hepatotoxicity.
• Provide nutritional support for weight loss.
• Arrange for DOT when indicated.

Patient Teaching

• Take medications exactly as prescribed — never miss doses.
• Complete the full course of treatment even if symptoms improve.
• Rifampin causes harmless orange-red urine, tears, and sweat.
• Report yellow skin, dark urine, or abdominal pain immediately (hepatotoxicity).
• Report vision changes, especially difficulty distinguishing red from green.
• Cover mouth and nose when coughing.
• Stay home until no longer contagious.
• Family members and close contacts should be tested for TB.

Drug-Resistant TB

• MDR-TB (multidrug-resistant) is resistant to isoniazid and rifampin.
• XDR-TB (extensively drug-resistant) is resistant to isoniazid, rifampin, fluoroquinolones, and injectable second-line agents.
• Prevention: never add a single drug to a failing regimen.
• Always use combination therapy and ensure adherence through DOT.

Common NCLEX Traps

• Active TB requires airborne isolation; latent TB does not.
• An N95 respirator (not a surgical mask) is required for staff.
• A negative pressure room is required for airborne precautions.
• Three negative sputum smears are needed to discontinue isolation.
• Isoniazid causes peripheral neuropathy → give vitamin B6.
• Ethambutol causes optic neuritis → test vision monthly.
• Rifampin turns body fluids orange → reassure the patient.
• HIV is the strongest risk factor for progression to active TB.
• Never add a single drug to a failing regimen — this drives resistance.

Key Takeaways

• TB is an airborne disease caused by Mycobacterium tuberculosis; suspected cases need a negative pressure room and N95 respirator.
• Latent TB is asymptomatic and non-contagious; active TB presents with chronic cough, low-grade evening fever, night sweats, and weight loss.
• Diagnosis uses PPD/IGRA screening, chest X-ray, AFB smear (contagiousness), and sputum culture (gold standard).
• The RIPE regimen (Rifampin, Isoniazid, Pyrazinamide, Ethambutol) is given for 2 months, followed by 4 months of RI for active TB.
• Critical drug teaching: Rifampin → orange secretions; Isoniazid → give B6; Pyrazinamide → hepatotoxicity; Ethambutol → optic neuritis.
• Use DOT to ensure adherence and prevent MDR-TB; never add a single drug to a failing regimen.