Discussion w11-12 652

Q-1

Bronchiectasis

Pathology - Bronchiectasis is a chronic condition where the bronchi are thickened and scarred, and the injury of the airway prevents the clearing of the mucus. It can affect a section of the lungs or several areas of both lungs. Individuals with bronchiectasis may have exacerbations, and over time affects airway exchange leading to respiratory failure, atelectasis, and lung infections (Börekçi & Müsellim, 2021).

Etiology - Bronchiectasis can be congenital or acquired including childhood infections, such as whooping cough or measles. Though, it increases with age and is typically due to infections, airway obstruction, cystic fibrosis (CF), systemic diseases, allergic bronchopulmonary aspergillosis, connective tissue diseases, and/or pulmonary infections (Börekçi & Müsellim, 2021). Airway blockage of a tumor or an inhaled object may also lead to bronchiectasis.

Risk factors – Individuals with medical conditions, such as cystic fibrosis, immunodeficiency disorders, COPD, and asthma at increased risk for bronchiectasis (Choi et al., 2021). Repeated infections including COVID, pneumonia, tuberculosis, also increase risks; therefore, individuals should limit exposure. COPD patients should decrease exposure to infections and smoking to prevent exacerbations, which may worsen pulmonary function and accelerate the progression of disease (Choi et al., 2021).

Signs/symptoms – The classic clinical manifestation of bronchiectasis include cough with the production of mucopurulent and tenacious sputum that lasts months to years. Patients may also report dyspnea, pleuritic chest pain, and rhinosinusitis (Börekçi & Müsellim, 2021). Clinical findings include crackles, wheezing, and clubbing.

Diagnostics – Patients with persistent or recurrent production of purulent sputum should be suspected of bronchiectasis. Lab tests including CBC, immunoglobulin quantitation, sputum smear/culture, and rheumatoid factor can help identify the underlying cause that resulted in bronchiectasis. A chest radiograph may identify dilated and thickened airways, but a CT scan of the chest is the preferred imaging modality (Choi et al., 2021). Clinical features of bronchiectasis on CT include airway dilation which is detected as parallel lines or end-on ring shadows, bronchial wall thickening, mucus plugs, and cysts of the bronchial wall.

Treatment – Childhood vaccines for whooping cough and measles can prevent infections and reduce complications. Patients with COPD, asthma, and other respiratory conditions should avoid fumes, smoke, and other harmful substances.

 

References

Börekçi, Ş., & Müsellim, B. (2021). Decreasing rate of unknown bronchiectasis etiology: Evaluation of 319 adult patients with bronchiectasis. Turkish Thoracic Journal, 22(1), 18–23. https://doi.org/10.5152/TurkThoracJ.2021.19142

Choi, H., Yang, B., Kim, Y. J., Sin, S., Jo, Y. S., Kim, Y., Park, H. Y., Ra, S. W., Oh, Y.-M., Chung, S. J., Yeo, Y., Park, D. W., Park, T. S., Moon, J.-Y., Kim, S.-H., Kim, T.-H., Yoon, H. J., Sohn, J. W., & Lee, H. (2021). Increased mortality in patients with non-cystic fibrosis bronchiectasis with respiratory comorbidities. Scientific Reports, 11(1), 1–9. https://doi.org/10.1038/s41598-021-86407-8

Q-2

Tuberculosis

Pathology

The inflammation produced with TB infection is granulomatous, with epithelioid macrophages and Langhans giant cells along with lymphocytes, plasma cells, maybe a few polymorphonuclear leucocytes, fibroblasts with collagen, and characteristic caseous necrosis in the center. The inflammatory response is mediated by a type IV hypersensitivity reaction (Agyeman & Ofori-Asenso, 2017).

Etiology

The association between poverty and TB is well-recognized, and the highest rates of TB were found in the poorest section of the community. TB occurs more frequently among low-income people living in overcrowded areas and persons with little schooling. Poverty may result in poor nutrition which may be associated with alterations in immune function. On the other hand, poverty resulting in overcrowded living conditions, poor ventilation, and poor hygiene-habits is likely to increase the risk of transmission of TB (Loddenkemper, Lipman, & Zumla, 2016).

Risk Factors

Specific risk factors include having lived in Asia, Latin America, Eastern Europe, or Africa for years; exposure to someone with infectious tuberculosis; residence in an institutional setting and homelessness. HIV infection Increases the risk for both progression to primary disease and reactivation of latent disease. In addition, active TB has been found to increase HIV viral loads (Loddenkemper, Lipman, & Zumla, 2016).

Signs and Symptoms

Cough for 2-3 weeks initially dry then later productive. Studies found that 50% of patients had cough over 2 weeks. Fever is usually low-grade and is less common in older population. Weight loss may be seen in patients with other suggestive symptoms (Agyeman & Ofori-Asenso, 2017). Malaise may be noticed in hindsight after treatment. Hemoptysis is present in <10% of patients typically with advanced disease. May be the result of sequelae such as bronchiectasis and is not represent in active disease (Loddenkemper, Lipman, & Zumla, 2016).

Diagnostics

The possibility of TB should be considered in any person with risk factors for TB exposure, who has suggestive symptoms such as fever, malaise, pleuritic chest pain, cough longer than 2-3 weeks, night sweats, and weight loss, hemoptysis, psychological symptoms, clubbing, erythema nodosum or chest x-ray abnormalities (Loddenkemper, Lipman, & Zumla, 2016). Investigations for active infection include chest x-ray, 3 sputum samples obtained for acid-fast bacilli (AFB), nucleic acid amplification testing (NAAT), complete blood count, and electrolytes. Stained smears should be made from sputum specimens to identify AFB, as this is the first bacteriologic evidence of infection and gives an estimate of how infectious the patient is (Loddenkemper, Lipman, & Zumla, 2016). Sputum culture supports the diagnosis of TB, is more sensitive and specific than smear staining, facilitates identification of the mycobacterium species by nucleic acid hybridization or amplification, and evaluates drug sensitivity (Agyeman & Ofori-Asenso, 2017). CT of the chest, although not done routinely, may be of use to exclude other pathology for example cancer. It is recommended that all patients who have TB should be tested for HIV within 2 months of diagnosis. Investigations for latent infection in a person exposed to M. tuberculosis but without signs of active TB are based on the tuberculin skin test (TST) or interferon gamma release assays (IGRAs). The TST and IGRA measure the response of T-cells to TB antigens (Agyeman & Ofori-Asenso, 2017).

Treatment

Treatment is initiated when TB is confirmed or strongly suspected and consists of an initial intensive phase and a subsequent continuation phase. The main goals are to cure the patient and to prevent further transmission of TB to others (Agyeman & Ofori-Asenso, 2017). Therapy for TB requires a minimum of 6 months of treatment except for culture-negative pulmonary TB. To reduce noncompliance rates, therapy can be given by a healthcare professional in conjunction with a local public health authority as DOT (Loddenkemper, Lipman, & Zumla, 2016). DOT can be given 5 days per week, or two or three times weekly, depending on the regimen and phase of treatment. Initial intensive phase treatment involves the preferred drugs of isoniazid, rifampin, pyrazinamide, and ethambutol, and lasts 8 weeks. Ethambutol may be discontinued immediately if the Mycobacterium tuberculosis isolate is sensitive to isoniazid and rifampin. If M. tuberculosis is sensitive to isoniazid and rifampin, in the continuation phase isoniazid and rifampin are given for 18 weeks, 26 weeks of total treatment (Agyeman & Ofori-Asenso, 2017).

Nutritional Approach

Reduced micronutrient intake, and especially intake of vitamins and minerals such as vitamins A, E, and C, zinc, and selenium, has been associated with an impaired immune response. There is evidence that at the time of diagnosis, patients with active TB have depressed blood concentrations of several micronutrients, including retinol, vitamins C and E, hemoglobin, zinc, iron, and selenium due to the immune system response to infection (Agyeman & Ofori-Asenso, 2017).

Food assistance is a potentially influential means for increasing adherence to TB treatment, reducing the costs to patients of staying in treatment, and for improving nutritional status. Food assistance may influence early case detection (encouraging patients to come sooner for diagnosis and treatment), and promote completion of the full course of treatment (Loddenkemper, Lipman, & Zumla, 2016). Both are important to decrease TB transmission. Periodic nutritional assessment, counseling on diet, nutritional management of symptoms and drug side-effects, may help TB patient maintain or increase their food intake and adhere to TB treatment (Agyeman & Ofori-Asenso, 2017).

References:

Agyeman, A. A., & Ofori-Asenso, R. (2017). Tuberculosis—an overview. Journal of Public Health and Emergency, 1, 7–7. https://doi.org/10.21037/jphe.2016.12.08

Loddenkemper, R., Lipman, M., & Zumla, A. (2016). Clinical Aspects of Adult Tuberculosis. Cold Spring Harbor Perspectives in Medicine, 6(1). https://doi.org/10.1101/cshperspect.a017848

Q-3

Restrictive Lung Disease

Restrictive lung diseases are a set of pulmonary disorders defined by restrictive patterns on spirometry, characterized by reduced distensibility of the lungs, compromising lung expansion, and lung volumes, particularly with reduced total lung capacity (King et al., 2019). Restrictive lung disease is often divided into two groups, depending on whether their cause is intrinsic or extrinsic.

I will focus on discussing interstitial lung disease (ILD), an intrinsic lung disease. ILD is an umbrella term used for a large group of diseases that cause scarring (fibrosis) of the lungs (King et al., 2019). ILDs are diffuse parenchymal lung diseases classified together because of similar clinical, radiographic, physiologic, or pathologic manifestations. The term “interstitial” reflects the pathologic appearance that the abnormality begins in the interstitium (King et al., 2019).

Pathology – Causes of ILD includes a broad range of diseases, exposures, and drugs, as well as idiopathic conditions (King et al., 2019). The most common identifiable causes of ILD are exposure to occupational and environmental agents, especially to inorganic and organic dusts, and drug-induced pulmonary toxicity (King et al., 2019). ILD can complicate the course of most rheumatic diseases (i.e., RA, lupus, and mixed connective tissue disease). Furthermore, idiopathic causes of ILD include sarcoidosis and idiopathic interstitial pneumonias.

Modifiable/nonmodifiable risk factors – Nonmodifiable risk factors include age and gender, family history, older age, autoimmune diseases and ethnic background (King et al., 2019). Some ILDs are more common in certain age groups or have a male or female predominance. Modifiable risk factors include smoking, prior medication use, radiation, chemotherapy, occupational and environmental exposures. Some ILD occur largely among current or former smokers, as well as some drugs having been reported to cause pulmonary toxicity (King et al., 2019).

Pertinent signs and symptoms – Patients with ILD commonly present with symptoms of progressive breathlessness with exertion (dyspnea) or a persistent nonproductive cough, chest discomfort, fatigue, and occasionally weight loss (King et al., 2019). They may have pulmonary symptoms associated with another disease, such as a connective tissue disease.

Diagnostics – Labs typically include BMP, CMP, CBC to evaluate hepatic and renal function, any evidence of anemia, polycythemia, leukocytosis, or eosinophilia (King et al., 2019). Chest x-ray is obtained to look for a reticular pattern, a common radiographic abnormality. Infectious processes can cause interstitial opacities on chest x-ray including fungal pneumonias, bacterial pneumonias, and viral pneumonias (King et al., 2019). Diagnostic approach to ILD relies on high resolution CT scan of the chest (King et al., 2019). Furthermore, I would obtain pulmonary function tests to assess spirometry and lung volumes as most ILDs have a restrictive defect with reductions in total lung capacity, functional residual capacity, and residual volume (King et al., 2019). The reductions in lung volumes become more pronounced as lung stiffness increases with disease progression.

Treatment regiments (pharmacological/nonpharmacological) – Approach to treatment varies based on the cause and type of ILD. Lung damage from ILDs is often irreversible and progressive, therefore treatment usually centers on relieving symptoms, improving quality of life, and slowing the disease’s progression (Distler et al., 2019). Medications, such as corticosteroids, can be used to decrease the amount of inflammation in the lungs. Oxygen therapy is another common treatment as it helps to make breathing easier for the patient. Lifestyle modifications should be included when treating these patients, such as smoking cessation, and reducing caffeine and carbonated beverage intake. A multidisciplinary approach is essential for diagnosis and treatment, particularly for patients with ILD related to autoimmune disease. Pulmonary rehab may be recommended in order to improve quality of life by giving patients techniques to improve lung efficiency, improve physical endurance and offer emotional support (Distler et al., 2019).

 

References

Distler, O., Highland, K., Gahlemann, M. (2019). SENSCIS Trial Investigators. Nintedanib for systemic sclerosis-associated interstitial lung disease. N Engl J Med, ;380(26):2518-2528. doi: 10.1056/NEJMoa1903076.

King, T., Flaherty, K., Hollingsworth, H. (2019). Approach to the adult with interstitial lung disease: Clinical evaluation. UpToDate. Retrieved from https://www.uptodate.com/contents/approach-to-the-adult-with-interstitial-lung-disease-clinical-evaluation?search=interstitial%20lung%20disease&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H5