. Pathophysiology Of Pulmonary Tuberculosis
Pulmonary tuberculosis is caused by Mycobacterium tuberculosis, an aerobic bacterium transmitted mainly through respiratory droplets. After inhalation, the bacilli reach the pulmonary alveoli, where they are phagocytized by macrophages.
However, due to their lipid-rich cell wall, M. tuberculosis resists intracellular destruction, allowing replication. The host immune response forms granulomas in an attempt to contain the infection. These granulomas may progress to caseous necrosis, pulmonary cavities, and hematogenous dissemination, depending on the immune response’s effectiveness.
Pharmacological Therapy For Pulmonary Tuberculosis
The treatment of pulmonary tuberculosis is divided into two main phases:
- Intensive Phase: Lasts two months and includes a combination of four drugs: rifampin, isoniazid, pyrazinamide, and ethambutol. This phase aims to rapidly reduce the bacterial load.
- Maintenance Phase: Lasts four months and includes rifampin and isoniazid. The goal is to eliminate remaining bacteria and prevent relapse.
Adherence to the treatment is crucial to avoid bacterial resistance. Directly Observed Treatment (DOT) is a widely used strategy to ensure compliance.
Mycobacterium Tuberculosis: The Causative Agent
Mycobacterium tuberculosis, also known as Koch’s bacillus, is a slow-growing bacterium highly resistant to adverse conditions. Its cell wall, rich in mycolic acids, confers resistance to disinfectants and hinders antibiotic penetration.
This bacterium is an obligate aerobe, requiring high oxygen levels, which explains its predilection for the lungs. Diagnosis is conducted through smear microscopy, culture in specific media, and molecular testing.
Symptoms
The main symptoms of the disease are severe weight loss, cough with or without secretion for more than three weeks, low fever usually in the afternoon, night sweats, excessive fatigue, lack of appetite, paleness and hoarseness. It is recommended that anyone with respiratory symptoms for a period longer than three weeks be investigated for tuberculosis.
Diagnosis
Tuberculosis is diagnosed using a chest X-ray, as well as laboratory tests and the patient’s sputum (bacilloscopy)
Prevention
To prevent tuberculosis, children are given the BCG vaccine, which only prevents the severe form of the disease. Contagion can also be avoided by treating and providing guidance to those infected, as well as improving the population’s living conditions, since the disease is associated with poverty and poor income distribution.
Treatment
Treatment can last six months to a year and is based on antibiotics. Treatment is free and available through the Unified Health System (SUS).
One of the difficulties in combating tuberculosis is the lack of adherence to treatment – because it is long and provides rapid results, some patients abandon it.
Which ends up causing the development of a form of the disease that is resistant to drugs, known as multidrug-resistant tuberculosis. This type of tuberculosis has been on the rise worldwide.
Transmission
Tuberculosis is transmitted via the respiratory route, through the elimination of aerosols produced by the coughing, speaking or sneezing of a person with active tuberculosis, without treatment; and the inhalation of aerosols by a susceptible individual. It is estimated that, over the course of a year, in a community, a person with active pulmonary and/or laryngeal tuberculosis, without treatment, can infect, on average, 10 to 15 people.
Tuberculosis is not transmitted through shared objects. Bacteria that settle on clothing, sheets, glasses and cutlery are unlikely to be dispersed into the air and therefore do not play an important role in the transmission of the disease.
With the start of treatment, transmission tends to gradually decrease, and in general, after 15 days, the risk of disease transmission is significantly reduced.
The bacteria responsible for tuberculosis are sensitive to sunlight and air circulation allows infectious particles to disperse. For this reason, ventilated environments with direct natural light reduce the risk of transmission. Cough etiquette, which consists of covering the mouth with the forearm or a tissue when coughing, is also an important measure to be considered in preventing the disease.
Nursing Care For Patients With Pulmonary Tuberculosis
Nursing care plays a vital role in managing pulmonary tuberculosis. Here are 10 key nursing interventions:
- Patient Education: Educate about the importance of adherence to treatment and the risks of abandonment.
- Medication Administration: Ensure medications are taken correctly and at prescribed times.
- Monitoring Side Effects: Observe for signs of hepatotoxicity and other adverse effects.
- Prevention of Transmission: Teach respiratory etiquette and the importance of ventilated environments.
- Regular Follow-Up: Schedule appointments to monitor treatment progress.
- Psychological Support: Provide emotional support to cope with stigma and the disease’s impact.
- Contact Identification: Assist in screening close contacts for early diagnosis.
- Promotion of Healthy Habits: Encourage a balanced diet and smoking cessation.
- Supervision of Directly Observed Therapy (DOT): Ensure adherence to the therapeutic regimen.
- Documentation and Communication: Record relevant information and communicate with the multidisciplinary team
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