ASSIGNMENT

ONLINE ASSIGNMENT

Topic: LUNG DISEASES

PREPARED BYVINOD P H

DEPT. OF NATURAL SCIENCE

S N T C NEDUNGANDA

INTRODUCTIONThe chest contains two lungs, one lung on the right side of the chest, the other on the left side of the chest. Each lung is made up of sections called lobes. The lung is soft and protected by the ribcage. The purposes of the lungs are to bring oxygen (abbreviated O2), into the

body and to remove carbon dioxide (abbreviated CO2). Oxygen is a gas that provides us energy while carbon dioxide is a waste product or "exhaust" of the body.

The cone-shaped lungs are sponge-like organs that fill the chest cavity and make up most of the lower respiratory tract. Their most important job is providing oxygen to capillaries so they can oxygenate blood.

Each lung is divided into lobes. The right lung has three, but the left lung has only two, thus allowing room to accommodate the heart.

Together, the lungs’ tissue surface is almost 40 times greater than the body’s outer surface, making the lungs (together) one of the largest organs in the body.

Each lung houses a bronchial tree, which gets its name from the intricate network of air passages that supply the lungs with air. The air-filled sacs in the lungs called alveoli resemble grape clusters. White blood cells known as macrophages, located inside each alveolus, ingest and destroy airborne irritants that enter the lungs. After you exhale, the lungs stay partly inflated because of a fluid called surfactant that is produced by special cells and secreted within the alveoli. Surfactant contains fatty proteins and helps to prevent lung infections.

Suffering from a respiratory disorder is one of the most common reasons for doctor visits in industrialized countries, where the air is filled with chemicals, pollutants, dust, pollen, bacteria, and viruses. The billions of microorganisms — bacteria, viruses, and fungi — in the air you breathe can enter the lungs, and they make respiratory infections quite common. Some infections, such as the common cold or sinusitis, affect the upper respiratory tract. Others, such as bronchitis and pneumonia, affect the lower respiratory tract

Acute bronchitis

Acute bronchitis is an infection of the the bronchi - the large airways. Acute bronchitis is common and is usually due to infection with a virus. Infection with a germ (a bacterial infection) is a less common cause

Symptoms of acute bronchitis

The main symptom is cough. You may also develop a high temperature (fever), headache, cold symptoms and aches and pains. Symptoms typically peak after 2-3 days and then gradually clear. However, it commonly takes 2-3 weeks for the cough to go completely after the other symptoms have gone. This is because inflammation in the airways caused by the infection may take some time to settle.

Symptoms are a nonproductive or mildly productive cough accompanied or preceded by URI symptoms, usually by > 5 days. Subjective dyspnea results from chest pain or tightness with breathing, not from hypoxia. Signs are often absent but may include scattered rhonchi and wheezing. Sputum may be clear, purulent, or occasionally contain blood. Sputum characteristics do not correspond with a particular etiology (ie, viral vs bacterial). Mild fever may be present, but high or prolonged fever is unusual and suggests influenza or pneumonia.

On resolution, cough is the last symptom to subside and often takes 2 to 3 wk or even longer to do so.

Diagnosis

Clinical evaluation Sometimes chest x-ray to exclude other disorders

Diagnosis is based on clinical presentation. Testing is usually unnecessary. However, patients who complain of dyspnea should have pulse oximetry to rule out hypoxemia. Chest x-ray is done if findings suggest serious illness or pneumonia (eg, ill appearance, mental status change, high fever, tachypnea, hypoxemia, crackles, and signs of consolidation or pleural effusion). Elderly patients are the occasional

exception, as they may have pneumonia without fever and auscultatory findings, presenting instead with altered mental status and tachypnea.

Sputum Gram stain and culture usually have no role. Nasopharyngeal samples can be tested for influenza and pertussis if these disorders are clinically suspected (eg, for pertussis, persistent and paroxysmal cough after 10 to 14 days of illness, only sometimes with the characteristic whoop and/or retching, exposure to a confirmed case—see also Pertussis : Diagnosis).

Cough resolves within 2 wk in 75% of patients. Patients with persistent cough should undergo a chest x-ray. Evaluation for noninfectious causes, including postnasal drip and gastroesophageal reflux disease, can usually be done clinically. Differentiation of cough-variant asthma may require pulmonary function testing.

Symptom relief (eg, acetaminophen, hydration, possibly antitussives)

Inhaled β-agonist or anticholinergic for wheezing

Acute bronchitis in otherwise healthy patients is a major reason that antibiotics are overused. Nearly all patients require only symptomatic treatment, such as acetaminophen and hydration. Evidence supporting efficacy of routine use of other symptomatic treatments, such as antitussives, mucolytics, and bronchodilators, is weak. Antitussives should be considered only if the cough is interfering with sleep (see Treatment). Patients with wheezing may benefit from an inhaled β 2 -agonist (eg, albuterol) or an anticholinergic (eg, ipratropium) for a few days. Oral antibiotics are typically not used except in patients with pertussis or during known outbreaks of bacterial infection. A macrolide such as azithromycin 500 mg po once, then 250 mg po once/day for 4 days or clarithromycin 500 mg po bid for 14 days is given.

PneumoniaPneumonia is an infection in one or both lung. It can be caused by fungi, bacteria, or viruses. Pneumonia causes inflammation in your lung’s air sacs, or alveoli. The alveoli fill with fluid or pus, making it difficult to breathe.

Symptoms of pneumonia can range from mild to life-threatening. The severity of your pneumonia usually depends on:

the cause of your inflammation the type of organism causing your infection your age your general health

There are five major types of pneumonia. They are:

Bacterial Pneumonia

Bacterial pneumonia can affect anyone at any age. It can develop on its own or after a serious cold or flu. The most common cause of bacterial pneumonia is Streptococcus pneumoniae. Bacterial pneumonia can also be caused by Chlamydophila pneumonia or Legionella pneumophila. Pneumocystis jiroveci

pneumonia is sometimes seen in those who have weak immune systems due to illnesses like AIDS or cancer.

Viral Pneumonia

In most cases, respiratory viruses can cause pneumonia, especially in young children and the elderly. Pneumonia is usually not serious and lasts a short time. However, the flu virus can cause viral pneumonia to be severe or fatal. It’s especially harmful to pregnant women or individuals with heart or lung issues. Invading bacteria can cause complications with viral pneumonia.

Mycoplasma Pneumonia

Mycoplasma organisms are not viruses or bacteria, but they have traits common to both. They are the smallest agents of disease that affect humans. Mycoplasmas generally cause mild cases of pneumonia, most often in older children and young adults.

Other Types of Pneumonia

Many additional types of pneumonia affect immune-compromised individuals. Tuberculosis and Pneumocystis carinii pneumonia (PCP) generally affect people with suppressed immune systems, such as those who have AIDS. In fact, PCP can be one of the first signs of illness in people with AIDS.

Less common types of pneumonia can also be serious. Pneumonia can be caused by inhaling food, dust, liquid, or gas, as well as by various fungi.

Symptoms

The general symptoms of bacterial pneumonia can develop quickly and may include:

chest pain shaking chills fever dry cough

wheezing muscle aches nausea vomiting rapid breathing rapid heartbeat difficulty breathing

Diagnosis Physical Exam

Crackling and bubbling sounds in the chest during inhalation are usually indicators of pneumonia. Wheezing may also be present. Your doctor may also have trouble hearing normal breathing sounds in different areas of your chest.

Diagnostic Tests

Chest X-rays can be used to determine if infection is present in your lungs. However, chest X-rays won’t show your type of pneumonia. Blood tests can provide a better picture of the type of pneumonia. Also, blood tests are necessary to see if the infection is in your bloodstream

AsthmaAsthma is a chronic disease involving the airways in the lungs. These airways, or bronchial tubes, allow air to come in and out of the lungs.

If you have asthma your airways are always inflamed. They become even more swollen and the muscles around the airways can tighten when something triggers your symptoms. This makes it difficult for air to move in and out of the lungs, causing symptoms such as coughing, wheezing, shortness of breath and/or chest tightness.

For many asthma sufferers, timing of these symptoms is closely related to physical activity. And, some otherwise healthy people can develop asthma symptoms only when exercising. This is called exercise-induced bronchoconstriction (EIB), or exercise-induced asthma (EIA). Staying active is an important way to stay healthy, so asthma shouldn't keep you on the sidelines. Your physician can develop a management plan to keep your symptoms under control before, during and after physicial activity.

People with a family history of allergies or asthma are more prone to developing asthma. Many people with asthma also have allergies. This is called allergic asthma.Occupational asthma is caused by inhaling fumes, gases, dust or other potentially harmful substances while on the job.

Childhood asthma impacts millions of children and their families. In fact, the majority of children who develop asthma do so before the age of five.

Symptoms

Asthma symptoms vary from person to person. You may have infrequent asthma attacks, have symptoms only at certain times — such as when exercising — or have symptoms all the time.

Asthma signs and symptoms include:

Shortness of breath Chest tightness or pain Trouble sleeping caused by shortness of breath, coughing or

wheezing A whistling or wheezing sound when exhaling (wheezing is a

common sign of asthma in children) Coughing or wheezing attacks that are worsened by a respiratory

virus, such as a cold or the flu

Diagnosis

Allergy testing to find out which allergens affect you, if any. A test to measure how sensitive your airways are. This is called a

bronchoprovocation test. Using spirometry, this test repeatedly measures your lung function during physical activity or after you receive increasing doses of cold air or a special chemical to breathe in.

A test to show whether you have another condition with the same symptoms as asthma, such as reflux disease, vocal cord dysfunction, or sleep apnea.

A chest x ray or an EKG (electrocardiogram). These tests will help find out whether a foreign object or other disease may be causing your symptoms.

Tuberculosis

Tuberculosis, MTB, or TB (short for tubercle bacillus), in the past also called phthisis, phthisis pulmonalis, or consumption, is a widespread, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis typically attacks the lungs, but can also affect other parts of the body. It is spread through the air when people who have an active TB infection cough, sneeze, or otherwise transmit respiratory fluids through the air. Most infections do not have symptoms, known as latent tuberculosis. About one in ten latent infections eventually progresses to active disease which, if left untreated, kills more than 50% of those so infected

Symptoms of TB disease depend on where in the body the TB bacteria are growing. TB bacteria usually grow in the lungs (pulmonary TB). TB disease in the lungs may cause symptoms such as

a bad cough that lasts 3 weeks or longer pain in the chest coughing up blood or sputum (phlegm from deep inside the lungs)

Symptoms

weakness or fatigue

weight loss no appetite chills fever sweating at night

Symptoms of TB disease in other parts of the body depend on the area affected.

People who have latent TB infection do not feel sick, do not have any symptoms, and cannot spread TB to others.

Diagnosis

During the physical exam, your doctor will check your lymph nodes for swelling and use a stethoscope to listen carefully to the sounds your lungs make while you breathe.

The most commonly used diagnostic tool for tuberculosis is a simple skin test, though blood tests are becoming more commonplace. A small amount of a substance called PPD tuberculin is injected just below the skin of your inside forearm. You should feel only a slight needle prick.

Within 48 to 72 hours, a health care professional will check your arm for swelling at the injection site. A hard, raised red bump means you're likely to have TB infection. The size of the bump determines whether the test results are significant.

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