Chapter 28
Bronchitis
90% viral Cough last for 3 weeks Clear mucoid sputum Headache, fever, malaise, hoarseness, dyspnea Breath sounds normal, rhonchi, crackles, or wheezes Chest X-Ray normal Presence of colored not reliable indicator of bacterial infection Self limiting - treatment is supportive. Cough suppressants Influenza gets antiviral medications (zanamivir or oseltamivir)
Lung Cancer Diagnostic Studies
A chest x-ray is the initial diagnostic test used for patients with suspected lung cancer. Approximately 5% of cases are found incidentally on a chest x-ray performed for unrelated conditions. The x-ray may identify a lung mass or infiltrate. Evidence of metastasis to the ribs or vertebrae and the presence of pleural effusion may also be seen on chest x-ray. CT scanning is used to further evaluate the lung mass. CT scans can identify the location and extent of masses in the chest, as well as any mediastinal involvement or lymph node enlargement. Sputum cytology can identify malignant cells, but results are positive in only 20% to 30% of specimens because the malignant cells are not always present in the sputum. Biopsy is necessary for a definitive diagnosis. Cells for biopsy can be obtained by CT-guided needle aspiration, bronchoscopy, mediastinoscopy, or video-assisted thoracoscopy. If a thoracentesis is performed to relieve a pleural effusion, the fluid is also analyzed for malignant cells. Bone scans and CT scans of the brain, pelvis, and abdomen are used to determine if metastatic disease is present. A complete history and physical examination, complete blood count (CBC) with differential, chemistry panel, liver function tests (LFTs), renal function tests, and pulmonary function tests are necessary. Magnetic resonance imaging (MRI) and/or positron emission tomography (PET) may also be used to evaluate and stage lung cancer.
TB drug therapy
Active disease Treatment is aggressive. Two phases of treatment Initial (8 weeks) Continuation (18 weeks) Four-drug regimen INH Rifampin (Rifadin) Pyrazinamide (PZA) Ethambutol
TB pneuomnia
Acute pneumonia may result when large amounts of tubercle bacilli are discharged from granulomas into the lung or lymph nodes. The clinical manifestations are similar to those of bacterial pneumonia. Because TB can infect organs throughout the body, various acute and long-term complications can result. TB in the spine (Pott's disease) can lead to destruction of the intervertebral disc and adjacent vertebrae. Central nervous system TB can cause severe bacterial meningitis. Abdominal tuberculosis can lead to peritonitis, especially in HIV-positive patients. The kidneys, adrenal glands, lymph nodes, and urogenital tract may also be affected.
Lung cancer later clinical manifestations
Anorexia, fatigue, weight loss Nausea/vomiting Hoarseness Unilateral paralysis of diaphragm Dysphagia Superior vena cava obstruction Palpable lymph nodes Mediastinal involvement
Miliary TB
Appropriately treated pulmonary TB typically heals without complications except for a scar and residual cavitation within the lung. Significant pulmonary damage, although rare, can occur in patients who are poorly treated or who do not respond to anti-TB treatment. Miliary TB is the widespread dissemination of the mycobacterium. The bacteria are spread via the bloodstream to distant organs. The infection is characterized by a large amount of TB bacilli and may be fatal if left untreated. It can occur as a result of primary disease or reactivation of latent infection. Clinical manifestations of miliary TB slowly progress over a period of days, weeks, or even months. Symptoms vary depending on which organs are infected. Hepatomegaly, splenomegaly, and generalized lymphadenopathy may be present
TB drug therapy more info
Because of the growing prevalence of multidrug-resistant TB, it is important to manage the patient with active TB aggressively. Drug therapy is divided into two phases: initial and continuation. In most circumstances, the treatment regimen for patients with previously untreated TB consists of a 2-month initial phase with four-drug therapy (INH, rifampin [Rifadin], pyrazinamide [PZA], and ethambutol). If drug susceptibility test results indicate that the bacteria are susceptible to all drugs, ethambutol may be discontinued. If PZA cannot be included in the initial phase (due to liver disease, pregnancy, etc.), the remaining three drugs are used for the initial phase. Noncompliance is a major factor in the emergence of multidrug resistance and treatment failures. Many individuals do not adhere to the treatment program in spite of understanding the disease process and the value of treatment. Directly observed therapy (DOT) involves providing the antituberculous drugs directly to patients and watching as they swallow the medications. It is the preferred strategy for all patients with TB to ensure adherence and is recommended for all patients at risk for noncompliance. DOT is an expensive but essential public health issue. The risk for reactivation of TB and MDR-TB is increased in patients who do not complete the full course of therapy. In many areas, the public health nurse administers DOT at a clinic site.
TB clinical manifestations
Can also present more acutely High fever Chills, generalized flulike symptoms Pleuritic pain Productive cough Adventitious breath sounds Extrapulmonary TB manifestations dependent on organs infected Sometimes TB has a more acute, sudden presentation. The patient may have a high fever, chills, generalized flulike symptoms, pleuritic pain, and a productive cough. Auscultation of the lungs may be normal or reveal crackles, rhonchi, and/or bronchial breath sounds. The clinical manifestations of extrapulmonary TB are dependent on the organs infected. For example, renal TB can cause dysuria and hematuria. Bone and joint TB may cause severe pain. Headaches, vomiting, and lympadenopathy may be present with TB meningitis.
Pneumonia
Community acquired is the 6th leading cause of death for adults > 65 Organisms invade via Aspiration Inhalation Hematogenous spread CAP/MCAP Until about 1936 pneumonia was the leading cause of death in the US. Development of sulfa and PCN changed the outcome of pneumonia in the US. Aspiration - high risk individuals, (LOC, swallowing,, cva, etoh) Opportunistic - alterned immune responses, protein calorie malnutrition, HIV, radiation, chemo, immune suppressing medications. CAP - not inpatient (resident) in past 14 days MCAP - 48 hrs. or more after admitted and not incubating at time of admission. High costs, many multi-drug resistant VAP more than 48 hrs after intubation
pneumonia assessment
Concepts - oxygenation, nutrition, activity, comfort Planning - clear breath sounds, normal breathing patterns, normal chest x-ray, no complications Nursing implementation - decrease risk
TB concepts
Concepts: Oxygenation; nutrition and metabolism, infection, comfort and rest, stress and coping, anxiety, family Planning: comply with therapeutic regimen; no recurrence of disease; normal pulmonary function; appropriate measures to prevent the spread of the disease Nursing Implementation : a. The ultimate goal it to eradicate TB worldwide. Screening, treatment of LTBI (latent TB infection), decrease those at risk (poverty, HIV, substance abuse, malnutrition, ...) b. Strongly suspected of TB placed on airborne precautions, get medical workup, appropriate drug therapy. HEPA masks. Screen close contacts Monthly sputum cultures until 2 consecutive specimens are neg. House well ventilated. Teach adherence. Notifying Public Health Department is mandatory. Public health nurse follows up. Direct observation therapy (DOT). Teach S/S of relapse (5% relapse). Evaluation: how will you know the patient goal are being met?
Pneumonia clinical manifestations in older adults
Confusion or stupor Hypothermia Diaphoresis Anorexia Abdominal pain
pneomnia clinical manifestations
Cough Fever Chills Dyspnea Tachypnea Pleuritic chest pain Sputum Rhonchi and crackles, rales
Pneuomnia diagnostic studies
History Physical examination Chest X-Ray Sputum specimen Blood cultures ABGs WBCs
TB nursing assessment
History Physical symptoms Productive cough Night sweats Afternoon temperature elevation Weight loss Pleuritic chest pain Crackles over apices of lungs Sputum collection Ask the patient about a previous history of TB, chronic illness, or any immunosuppressive medications. Obtain social and occupational history to determine risk factors for transmission of TB. Assess the patient for productive cough, night sweats, afternoon temperature elevation, weight loss, pleuritic chest pain, and abnormal lung sounds. If the patient has a productive cough, early morning is the ideal time to collect sputum specimens for an acid-fast bacillus (AFB) smear.
TB risk factors
Homeless Residents of inner-city neighborhoods Foreign-born persons Living or working in institutions (includes health care workers) IV injecting drug users Poverty, poor access to health care Immunosuppression Asian descent TB occurs disproportionately in the poor, the underserved, and minorities. In the United States, persons at risk include the homeless, residents of inner-city neighborhoods, foreign-born persons, those living or working in institutions (long-term care facilities, prisons, shelters, hospitals), IV injecting drug users, persons at poverty level, and those with poor access to health care. Immunosuppression from any etiology (e.g., HIV infection, malignancy, long-term corticosteroid use) increases the risk of active TB infection. The prevalence of TB in the United States is highest in those of Asian descent.
Latent TB drug therapy
In people with LTBI, drug therapy helps prevent a TB infection from developing into active TB disease. Because there are fewer bacteria in a person with LTBI, treatment is much easier. Usually, only one drug is needed. The standard treatment regimen for LTBI is 9 months of daily isoniazid (INH). It is an effective and inexpensive drug that the patient can take orally. The 9-month regimen is more effective, but compliance issues may make the 6-month regimen preferable. For HIV patients and those with fibrotic lesions on chest x-ray, INH is given for 9 months. An alternative 3-month regimen of INH and rifapentine (Priftin) may be used for otherwise healthy patients who are not presumed to be infected with drug-resistant bacilli. A 4-month therapy with rifampin may be indicated if the patient is resistant to INH. Due to reports of severe liver injury and deaths, the CDC does not recommend the combination of rifampin and pyrazinamide for treatment of LTBI. Bacille Calmette-Guérin (BCG) vaccine is a live, attenuated strain of Mycobacterium bovis. The vaccine is given to infants in parts of the world where there is a high prevalence of TB. In the United States, it is typically not recommended because of the low risk of infection, the vaccine's variable effectiveness against adult pulmonary TB, and potential interference with TB skin test reactivity. The BCG vaccine should be considered only for very select individuals who meet specific criteria (e.g., health care workers continually exposed to patients with MDR-TB and infection control precautions are not successful). The BCG vaccination can result in a false-positive TST. IGRA results are not affected.
LTBI - asymptomatic
LTBI - asymptomatic Pulmonary TB Takes 2-3 weeks to develop symptoms. Initial dry cough that becomes productive Constitutional symptoms (fatigue, malaise, anorexia, weight loss, low-grade fever, night sweats) Dyspnea and hemoptysis late symptoms Cough becomes frequent. Hemoptysis is not common and is usually associated with advanced disease. Dyspnea is unusual. People with LTBI have a positive skin test but are asymptomatic. Symptoms of pulmonary TB usually do not develop until 2 to 3 weeks after infection or reactivation. The characteristic pulmonary manifestation is an initial dry cough that frequently becomes productive with mucoid or mucopurulent sputum. Active TB disease may initially manifest with constitutional symptoms such as fatigue, malaise, anorexia, unexplained weight loss, low-grade fevers, and night sweats. Dyspnea is a late symptom that may signify considerable pulmonary disease or a pleural effusion. Hemoptysis, which occurs in less than 10% of patients with TB, is also a late symptom.
Lung cancer clinical manifetations more info
Lung cancer frequently presents as a lobar pneumonia that does not respond to treatment. One of the most common symptoms of lung cancer, and often the one reported first, is a persistent cough. Blood-tinged sputum may be produced because of bleeding caused by the malignancy. The patient may complain of dyspnea or wheezing. Chest pain, if present, may be localized or unilateral, ranging from mild to severe. Later manifestations include nonspecific systemic symptoms such as anorexia, fatigue, weight loss, and nausea and vomiting. Hoarseness may be present as a result of involvement of the laryngeal nerve. Unilateral paralysis of the diaphragm, dysphagia, and superior vena cava obstruction may occur because of intrathoracic spread of the malignancy. Sometimes there are palpable lymph nodes in the neck or axilla. Mediastinal involvement may lead to pericardial effusion, cardiac tamponade, and dysrhythmias.
Lung cancer metastsis
Lung cancers metastasize primarily by direct extension and via the blood and lymph system. The common sites for metastasis are the liver, brain, bones, lymph nodes, and adrenal glands.
adenocarcinoma
Moderate Accounts for 30% to 40% of lung cancers. Most common lung cancer in people who have not smoked; more common in women. Peripherally located. Often has no clinical manifestations until widespread metastasis is present. Surgical resection may be attempted depending on the staging. Does not respond well to chemotherapy.
Pneuomnia complications
More prevalent in older or chronic disease Pleurisy Pleural effeusion Atelectasis Bacteremia Empyema Pericarditis Meningitis Sepsis Acute respiratory failure Pneumothorax Lung abscess
TB colab care
Most patients with TB are treated on an outpatient basis. Many people can continue to work and maintain their lifestyles with few changes. Patients with sputum smear positive TB are generally considered infectious for the first 2 weeks after starting treatment. Advise these patients to restrict visitors, travel on public transportation, and trips to public places. Hospitalization may be needed for the severely ill or debilitated. The mainstay of TB treatment is drug therapy. Promoting and monitoring compliance is critical for treatment to be successful.
Non small cell lung cancer
NSCLC includes squamous cell carcinoma, adenocarcinoma, and large-cell carcinoma.
MDR TB
Occurs when a strain develops resistance to two of the most potent first-line anti-TB drugs Extensively drug-resistant TB (XDR-TB) resistant to any fluoroquinolone plus any injectable antibiotic Several causes for resistance occur Once a strain of M. tuberculosis develops resistance to two of the most potent first-line antituberculosis drugs (e.g., isoniazid [INH], rifampin [Rifadin]), it is defined as multidrug-resistant tuberculosis (MDR-TB). Extensively drug-resistant TB (XDR-TB) occurs when the organism is also resistant to any of the fluoroquinolones plus any injectable antibiotic agent. Resistance results from several problems, including incorrect prescribing, lack of public health case management, and patient nonadherence to the prescribed regimen.
Pleural TB
Pleural TB can result from either primary disease or reactivation of a latent infection. A pleural effusion is caused by bacteria in the pleural space, which trigger an inflammatory reaction and a pleural exudate of protein-rich fluid. Empyema is less common than effusion but may occur from large numbers of tubercular organisms in the pleural space.
pneomnia collab care
Pneumococcal vaccine Prompt treatment Mobility improves diaphragm movement ATB therapy if bacterial Hydration Small frequent meals
Lung Cancer early clinical manifestations
Pneumonitis Persistent cough with sputum (most common) Hemoptysis Dyspnea Wheezing Chest pain
large cell carcinoma
Rapid Accounts for 10% of lung cancers. Composed of large-sized cells that are anaplastic and often arise in the bronchi. Is highly metastatic via lymphatics and blood. Surgery is not usually attempted because of high rate of metastases. Tumor may be radiosensitive but often recurs.
Screening for Lung cancer
Screening for high-risk patients is supported by the recent National Lung Screening Trial (NLST). This study showed a 20% decrease in deaths from lung cancer in patients who underwent screening with low-dose spiral CT scanning compared with those who had chest x-rays. Only those patients who meet the following criteria should be considered for screening: 55 to 74 years old, current or former smokers with at least a 30 pack-year smoking history, former smokers who have quit within the past 15 years, no history of lung cancer, not on home oxygen.
squamous cell carnicomna
Slow growing Centrally located so produces early symptoms of nonproductive cough and hemoptysis. Does not have a strong tendency to metastasize. Surgical resection may be attempted. Adjuvant chemotherapy and radiation Depending on the staging, life expectancy is better than for small-cell lung cancer.
Lung Cancer
Smoking accounts for 80 to 90% Mutated cells Two primary types Paraneoplastic syndrome Hypercalcemia Syndrome of inappropriate antidiuretic hormone Adrenal hypersecretion Hematologic disorders Neurologic syndromes Often associated with SCLC Leading cause of cancer-related deaths in the US. Accounts for 28% of all cancer deaths. High mortality, low cure rates. Smoking accounts for 80 to 90%. Contains 60 carcinogens . Carbon monoxide and nicotine interfere with normal cell development. 10 to 15 years after quitting the risk is the same as nonsmoker. Carcinogens cause cells to mutate. Genetic factors also play a role. Non-small cell NSCLC 80%; small cell SCLC 20% Paraneoplastic syndrome caused by humoral factors (hormones and cytokines) excreted by tumor cells or by an immune response against the tumor. May manifest before diagnosis of the tumor.
TB Etiology and patho
Spread via airborne droplets Can be suspended in air for minutes to hours Transmission requires close, frequent, or prolonged exposure. NOT spread by touching, sharing food utensils, kissing, or other physical contact Can spread to other areas M. tuberculosis is a gram-positive, acid-fast bacillus that is usually spread from person to person via airborne droplets produced by breathing, talking, singing, sneezing, and coughing. A process of evaporation leaves small droplet nuclei, 1 to 5 μm in size. These droplets contain M. tuberculosis. Because they are so small, the particles remain suspended in the air for minutes to hours and are transmitted via inhalation to another person. TB is not highly infectious, and transmission usually requires close, frequent, or prolonged exposure. Brief exposure to a few tubercle bacilli rarely causes an infection. Factors that influence the likelihood of transmission include the (1) number of organisms expelled into the air, (2) concentration of organisms (small spaces with limited ventilation would mean higher concentration), (3) length of time of exposure, and (4) immune system of the exposed person. The disease cannot be spread by touching, sharing food utensils, kissing, or any other type of physical contact. Once inhaled, these small particles lodge in the bronchiole and alveolus. A local inflammatory reaction occurs, and the focus of infection is established. This is called the Ghon focus, which develops into a granuloma, the hallmark of TB. The formation of a granuloma is a defense mechanism aimed at walling off the infection and preventing further spread. Replication of the bacillus is inhibited, and the infection is stopped. Seventy percent of immunocompetent adults infected with TB are able to completely kill the mycobacteria. The remainder will contain the mycobacteria in a nonreplicating dormant state. Of these individuals, 5-10% will go on to develop active TB infection when the bacteria begin to multiply months or years later.
Lung Cancer other therapies
Stents are used alone or in combination with other techniques for relief of dyspnea, cough, or respiratory insufficiency. The advantage of an airway stent is that it supports the airway wall against collapse or external compression and can delay extension of tumor into the airway lumen. Radiofrequency ablation therapy is being used to treat small NSCLC lung tumors that are near the outer edge of the lungs. This therapy is used as an alternative to surgery in patients who cannot or elect not to have surgery. A thin, needle-like probe is inserted through the skin into the tumor. CT scans are used to guide placement. An electric current is then passed through the probe, which heats and destroys tumor cells. Local anesthesia is used for this outpatient procedure.
Lung Cancer Treatments etc
Stereotactic body radiotherapy (SBRT), also called stereotactic surgery or radiosurgery, is a new lung cancer treatment. SBRT provides an option for patients with very early stage lung cancers who are not surgical candidates because of other medical reasons. It is a type of radiation therapy that uses high doses of radiation delivered very accurately to the tumor. SBRT is an outpatient procedure that uses special positioning procedures and radiology techniques so that a higher dose of radiation can be delivered to the tumor, and only a smaller part of the healthy lung is exposed. Therapy is given over one to three days. Chemotherapy is the primary treatment for SCLC. In NSCLC, chemotherapy may be used in the treatment of nonresectable tumors or as adjuvant therapy to surgery. A variety of chemotherapy drugs and multidrug regimens (i.e., protocols) have been used. Chemotherapy for lung cancer typically consists of combinations of two or more drugs.
Table 28 18 Nursing Assessment for Lung Cancer
Subjective Data Important Health Information Past health history: Exposure to secondhand smoke, airborne carcinogens (e.g., asbestos, radon, hydrocarbons), or other pollutants; urban living environment; chronic lung disease (e.g., TB, COPD, bronchiectasis) Medications: Cough medicines or other respiratory medications Functional Health Patterns Health perception-health management: Smoking history, including amount per day and number of years; family history of lung cancer; frequent respiratory tract infections Nutritional-metabolic: Anorexia, nausea, vomiting, dysphagia (late); weight loss; chills Activity-exercise: Fatigue; persistent cough (productive or nonproductive); dyspnea at rest or with exertion, hemoptysis (late symptom) Cognitive-perceptual: Chest pain or tightness, shoulder and arm pain, headache, bone pain (late symptom) Objective Data General Fever, neck and axillary lymphadenopathy, paraneoplastic syndrome (e.g., syndrome of inappropriate ADH secretion) Integumentary Jaundice (liver metastasis); edema of neck and face (superior vena cava syndrome), digital clubbing Respiratory Wheezing, hoarseness, stridor, unilateral diaphragm paralysis, pleural effusions (late signs) Cardiovascular Pericardial effusion, cardiac tamponade, dysrhythmias (late signs) Neurologic Unsteady gait (brain metastasis) Musculoskeletal Pathologic fractures, muscle wasting (late) Possible Diagnostic Findings Observance of lesion on chest x-ray, CT scan, or PET scan; MRI findings of vertebral, spinal cord, or mediastinal invasion; positive sputum or bronchial washings for cytologic studies; positive fiberoptic bronchoscopy and biopsy findings
table 28-7
Subjective Data Important Health Information Past health history: Lung cancer, COPD, diabetes mellitus, chronic debilitating disease, malnutrition, altered consciousness, immunosuppression, exposure to chemical toxins, dust, or allergens Medications: Antibiotics; corticosteroids, chemotherapy, or any other immunosuppressants Surgery or other treatments: Recent abdominal or thoracic surgery, splenectomy, endotracheal intubation, or any surgery with general anesthesia; tube feedings Functional Health Patterns Health perception-health management: Cigarette smoking, alcoholism; recent upper respiratory tract infection, malaise Nutritional-metabolic: Anorexia, nausea, vomiting; chills Activity-exercise: Prolonged bed rest or immobility; fatigue, weakness; dyspnea, cough (productive or nonproductive); nasal congestion Cognitive-perceptual: Pain with breathing, chest pain, sore throat, headache, abdominal pain, muscle aches Objective Data General Fever, restlessness or lethargy; splinting of affected area Respiratory Tachypnea; pharyngitis; asymmetric chest movements or retraction; decreased excursion; nasal flaring; use of accessory muscles (neck, abdomen); grunting; crackles, friction rub on auscultation; dullness on percussion over consolidated areas, increased tactile fremitus on palpation; pink, rusty, purulent, green, yellow, or white sputum (amount may be scant to copious) Cardiovascular Tachycardia Neurologic Changes in mental status, ranging from confusion to delirium Possible Diagnostic Findings Leukocytosis; abnormal ABGs with↓or normal PaO2,↓PaCO2, and ↑pH initially, and later↓PaO2,↑PaCO2, and↓pH; positive sputum on Gram stain and culture; patchy or diffuse infiltrates, abscesses, pleural effusion, or pneumothorax on chest x-ray*
Lung Cancer Treatments
Surgical resection is the treatment of choice in NSCLC stages I-IIIa without mediastinal involvement, because resection provides the best chance for a cure. For other NSCLC stages, patients may require surgery in conjunction with radiation therapy and/or chemotherapy. Fifty percent of NSCLCs are not resectable at the time of diagnosis. The surgical procedures that may be performed include pneumonectomy (removal of one entire lung), lobectomy (removal of one or more lobes of the lung), or segmental or wedge resection procedures. Video-assisted thoracic surgery (VATS) may be used to treat lung cancers near the outside of the lung. Surgery is generally not indicated for SCLC because of its rapid growth and dissemination at the time of diagnosis. Radiation therapy may be used as treatment for both NSCLC and SCLC. Radiation therapy may be given as curative therapy, palliative therapy (to relieve symptoms), or adjuvant therapy in combination with surgery or chemotherapy. Radiation therapy may be used as primary therapy in the individual who is unable to tolerate surgical resection due to comorbidities. Radiation therapy also relieves symptoms of dyspnea and hemoptysis resulting from bronchial obstructive tumors and treats superior vena cava syndrome. It can also be used to treat pain that is caused by metastatic bone lesions or cerebral metastasis. Sometimes radiation is used preoperatively to reduce the tumor mass before surgical resection. Complications of radiation therapy include esophagitis, skin irritation, nausea and vomiting, anorexia, and radiation pneumonitis.
TB classification
TB can also be classified according to its presentation - primary, latent, or reactivated and whether it is pulmonary or extrapulmonary. Primary infection occurs when the bacteria are inhaled and initiate an inflammatory reaction. The majority of people mount effective immune responses to encapsulate these organisms for the rest of their lives, preventing primary infection from progressing to disease. Latent TB infection (LTBI) is a TB infection in a person who does not have active TB disease. These individuals are asymptomatic and cannot transmit the TB bacteria to others. An estimated 10 to 15 million Americans have LTBI, of which 5-10% will develop active TB disease at some point. Therefore treatment of LTBI is important. If the initial immune response is not adequate, the body cannot contain the organisms, the bacteria replicate, and active TB disease results. When active disease develops within the first 2 years of infection, it is termed primary TB. Post-primary, or reactivation TB, is defined as TB disease occurring 2 or more years after the initial infection. Individuals co-infected with HIV are at greatest risk for developing active TB.
Lung Cancer treatments continued
Targeted therapy uses drugs that block the growth of molecules involved in specific aspects of tumor growth. Because they inhibit growth rather than directly kill cancer cells, targeted therapy may be less toxic than chemotherapy. One type of targeted therapy for patients with NSCLC inhibits tyrosine kinase, an enzyme associated with epidermal growth factor receptor. These drugs block signals for growth in the cancer cells. An example of this type of drug is erlotinib (Tarceva). Another kinase inhibitor, crizotinib (Xalkori), is used to treat patients with NSCLC who have an abnormal anaplastic lymphoma kinase (ALK) gene. This drug directly inhibits the kinase protein produced by the ALK gene that is responsible for cancer development and growth. Other drugs inhibit the growth of new blood vessels (angiogenesis) by targeting vascular endothelial growth factor. An example of this type of drug is bevacizumab (Avastin). Patients with SCLC have early metastases, especially to the central nervous system. Most chemotherapy does not penetrate the blood-brain barrier. Therefore after successful systemic treatment, the patient is at risk for cerebral metastases. Prophylactic radiation has been shown to decrease the incidence of cerebral metastases and improve the survival rate in patients with limited SCLC. Bronchoscopic laser therapy makes it possible to remove obstructing bronchial lesions. It is a safe and effective treatment of endobronchial obstructions from tumors. Symptoms of airway obstruction are relieved as a result of thermal necrosis and shrinkage of the tumor. The procedure may be repeated as needed. Photodynamic therapy can be used to treat very early stage lung cancers that are confined to the outer layers of the airways. It can also be used to remove lesions obstructing the airway. Porfimer (Photofrin) is injected IV and selectively concentrates in tumor cells. After a set time period (usually 48 hours), the tumor is exposed to laser light via bronchoscopy, activating the drug and causing cell death. Necrotic tissue is removed with bronchoscopy a few days later. This process can be repeated as needed.
Lung Cancer clinical manifestations
The clinical manifestations of lung cancer are usually nonspecific and appear late in the disease process. Symptoms may be masked by a chronic cough attributed to smoking or smoking-related lung disease. Manifestations depend on the type of primary lung cancer, its location, and metastatic spread.
TB skin test
The tuberculin skin test (TST) (Mantoux test) using purified protein derivative (PPD) is the standard method to screen people for M. tuberculosis. The test is administered by injecting 0.1 mL of PPD intradermally on the dorsal surface of the forearm. The test is read by inspection and palpation 48 to 72 hours later for the presence or absence of induration. The indurated area (if present) is measured and recorded in millimeters. Induration (not redness) at the injection site means the person has been exposed to TB and has developed antibodies. (Antibody formation would occur 2 to 12 weeks after the initial exposure to the organisms.) Interferon-γ release assays (IGRAs) provide another screening tool for TB. These whole blood assays detect INF-γ released from T-cell lymphocytes in response to mycobacterial antigens. Examples of IGRAs include QuantiFERON-TB test and the T-SPOT. Test results are available in a few hours. IGRAs offer several advantages over the TST in that they require only one patient visit, are not subject to reader bias, have no booster phenomenon, and are not affected by prior BCG vaccination. The cost of an IGRA is substantially higher than the TST. Current guidelines suggest that both tests are viable options and that selection should be based on context and reasons for testing. Neither IGRAs or TST can distinguish between LTBI and active TB infection. LTBI can only be diagnosed by excluding active TB.
TB
Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis. It usually involves the lungs, but any organ can be infected. TB is a primary cause of death worldwide from a potentially curable infectious disease. It is the leading cause of mortality in patients with HIV/acquired immunodeficiency syndrome (AIDS). The incidence of TB worldwide declined until the mid-1980s when HIV disease emerged. The major factors that contributed to the resurgence of TB were (1) high rates of TB among patients with HIV infection and (2) the emergence of multidrug-resistant (MDR) strains of M. tuberculosis. Worldwide, more than two billion people (one third of the population) are currently infected with TB. Although the prevalence of TB has increased in Europe, in the United States it has steadily declined since reaching a resurgence peak in 1992.
small cell lung cancer
Very rapid Accounts for about 20% of lung cancers. Most malignant form of lung cancer. Spreads early via lymphatics and bloodstream; frequent metastasis to brain. Associated with endocrine disturbances. Chemotherapy mainstay of treatment but overall poor prognosis. Radiation is used as adjuvant therapy as well as palliative measure.
