Common Causes of Pulmonary Fibrosis

Immune system abnormalities (rheumatoid arthritis, scleroderma, polymyositis, and rarely, systemic lupus erythematosus)

Infection (viruses, rickettsias, rnycoplasmas, disseminated tuberculosis)

Mineral dust (silica, carbon, metal dusts, asbestos)

Organic dust (molds, bird droppings)

Gases, fumes, and vapors (chlorine, sulfur dioxide)

Therapeutic or industrial radiation

Drugs and poisons (methotrexate, busulfan, cyclophosphamide, gold, penicillamine, nitrofurantoin, sulfonamides, amiodarone, paraquat)

 

Pneumonia

Text A. Introduction.

Pneumonia is an infection of the lungs that involves the small air sacs (alveoli) and the tissues around them.

Often, pneumonia is the final illness in people who have other serious, chronic dis­eases. It's the sixth most common cause of death overall, and the most common fatal infection ac­quired in hospitals. In developing countries pneumonia is either the leading cause of death or second only to dehydration from severe diarrhea.

Causes

Pneumonia isn't a single illness but many dif­ferent ones, each caused by a different micro­scopic organism. Usually pneumonia starts after organisms are inhaled into the lungs, but some­times the infection is carried to the lungs by the bloodstream or it migrates to the lungs directly from a nearby infection.

In adults, the most common causes are bacte­ria, such as Streptococcus pneumoniae, Staphylococcus aureus, Legionella, and Hemophilus influenzae. Viruses, such as influenza and chickenpox, can also cause pneumonia. Mycoplasma pneumo­niae, a bacterialike organism, is a particularly common cause of pneumonia in older children and younger adults. Some fungi also cause pneu­monia.

Some people are more susceptible to pneumo­nia than others. Alcoholism, cigarette smoking, diabetes, heart failure, and chronic obstructive pulmonary disease all predispose people to pneu­monia. The very young and very old are also at higher than average risk. So are people whose immune system is suppressed by certain drugs (such as those used to treat cancer and those used to prevent the rejection of an organ trans­plant). People who are debilitated, bedridden, paralyzed, or unconscious or who have a disease that impairs the immune system, such as AIDS, are also at risk.

Pneumonia may follow surgery, particularly abdominal surgery, or an injury (trauma), partic­ularly a chest injury, because of the resulting shallow breathing, impaired ability to cough, and retention of mucus. Staphylococcus aureus, pneumococci, Hemophilus influenzae, or a combina­tion of these organisms is often the cause.

Symptoms and Diagnosis

Common symptoms of pneumonia are a cough that produces sputum, chest pain, chills, fever, and shortness of breath. These symptoms may vary, however, depending on how extensive the disease is and which organism is causing it. When a person appears to have pneumonia, a doctor listens to the chest with a stethoscope to evaluate the condition. Pneumonia usually produces dis­tinctive changes in the way sounds are transmit­ted, which can be heard with the stethoscope.

In most cases, the diagnosis of pneumonia is confirmed with a chest x-ray, which often helps determine which organism is causing the disease. Sputum and blood specimens also are examined in an attempt to identify the organism causing pneumonia. However, the precise organism can't be identified in up to half of people who have pneumonia.

Treatment

Deep-breathing exercises and therapy to clear secretions help prevent pneumonia in people at high risk, such as those who have had chest sur­gery and those who are debilitated. People with pneumonia also need to clear secretions.

Often, people who aren't very sick can take oral antibiotics and remain at home. The elderly and those who are short of breath or have preexisting heart or lung disease are generally hospitalized and given intravenous antibiotics. They may also need supplemental oxygen, intravenous fluids, and mechanical respiratory support.

 

Notes:

susceptible восприимчивый

chicken-pox ветряная оспа

bedridden прикованный к постели (болезнью); дряхлый, бессильный