吉林大学 教师教案 (2010 ~2011 学年第 1 学期 ) 课程名称 : 病理学年级 :2008 级七年制教研室 : 病理学系任课教师 : 王琳 吉林大学教务处制

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1 吉林大学 教师教案 (2010 ~2011 学年第 1 学期 ) 课程名称 : 病理学年级 :2008 级七年制教研室 : 病理学系任课教师 : 王琳 吉林大学教务处制

2 教案 课程名称 : 病理学 授课教师王琳所在单位白求恩医学院 课程类型理论授课时间 (7-8) 授课对象 2008 级七年制 教学内容提要 时间分配及备注 Respiratory System-1 Normal respiratory system Penumonia Classification of pneumonia On the basis of etiology, anatomic distribution, inflammatory features Acute Bacterial pneumonia Lobar pneumonia Lobar pneumonia is fibrinous inflammation that affects a large area of a lobe and even an entire lobe of a lung by acute bacterial infection. 1. Etiology: Streptococcus pneumoniae 2. Pathologic Features 1)Congestion: Affected lobe(s) is (are) heavy, boggy and red. In the alveoli: -vascular congestion, -proteinaceous fluid, -few neutrophils, -numerous bacteria 2) Red hepatization: The lobe is red, firm with liver-like consistency. Alveolar space filled with RBCs, neutrophils and fibrin. The basic alveolar architecture is maintained and congestive. 10min 介绍肺炎的分类方法并进行解释 讲解概念中包含的信息 20min 首先介绍每个时期的大体改变, 提出问题后再讲镜下改变, 强调大叶性肺炎是纤维素性炎 3) Grey hepatization: The lobe is dry, grey, and firm with liver-like consistency. RBCs get lysed, while the fibrinous exudate persists within the alveoli. The basic alveolar architecture is maintained and ischemic.

3 4) Resolution: The favorable final stage in which consolidated exudate undergoes enzymatic digestion and cellular degradation and clearance. 3. Clinical Features: fever, shaking chills, cough, productive of rusty sputum, percussion dullness, breath sound, x-ray opacity 10min 以病例方式介绍大叶性肺炎的临床表现, 通过分析其与病理变化间的关系, 说明病理学在临床医学中的重要作用 Lobular Pneumonia (Bronchopneumonia) 5min Infection is centered on the bronchi but with the extension of the inflammatory exudate into the alveoli, causing a lobular distribution. It is characterized by foci of acute suppurative inflammation centered on bronchioles. 1. Etiology: S aureus, Haemophilus influenzae and S pneumoniae 2. Pathologic Features 15min Foci of inflammatory consolidation: distribute in patches 复习化脓性炎症 throughout one or several lobes, frequently bilateral and basal 的概念及病变特 Well-developed lesions: slightly elevated, dry, granular, grey-red 点 to yellow, and poorly delimited at their margins. Foci vary in size. Confluence of these foci producing the appearance of total lobular consolidation. The lung substance immediately surrounding areas of consolidation: usually slightly hyperemic and edematous, but the large intervening areas are generally normal. 3. Clinical Features: The major symptoms: fever, and cough 5min productive of purulent sputum. Abscess formation. The characteristic

4 radiologic appearance: focal opacities. Complications of Acute Air Space pneumonia 1) abscess formation; 2) empyema; 3) fibrinous pleuritis; 4) organization: pulmonary carnification Viral Pneumonia Pathology: 1) A predominance of interstitial with widened, edematous alveolar walls containing lymphocytes and plasma cells infiltrate. The alveolar spaces are airfilled. 2) The formation of hyaline membranes, reflecting diffuse alveolar damage. 3) Certain viruses cause necrosis of bronchial or alveolar epithelium in severe infections. 4) Characteristic cytopathic changes are inclusion bodies, and multinucleated giant cells, which may be useful in identifying the specific agent if tissue biopsies are taken. 5min 10min 强调与细菌性肺炎的不同 Severe Acute Respiratory Syndrome 5min Mycoplasmal Pneumonia Infection with this organisms evokes an acute inflammation that is usually restricted to the interstitium without involvement of the alveolar spaces. Summary 5min

5 教学目的及要求 教学重点与难点 教学手段 参考资料 掌握 : 各种肺炎的病理变化 熟悉 : 肺炎的临床病理联系 了解 : 肺炎的病因 重点 : 各种肺炎的基本病理变化 难点 : 各种肺炎之间的差别 多媒体 + 板书 + 双语供 8 年制及 7 年制用 病理学 主编陈杰 李甘地, 人民卫生出版社 Robbins Basic Pathology 主编 Vinay Kumar,Elsevier Science 肺炎是常见的呼吸道炎症性疾病, 同学们并不陌生 首先介绍肺炎的 分类, 然后以肺炎的症状作为切入点来讲解, 以各种肺炎的比较进行 课后小结 总结, 同学们理解的比较好, 但是反应有些英文不能很好理解, 所以, 在总结时用汉语再次强调重点内容 授课教师 : 王琳

6 Chapter 7 Diseases of the Respiratory System Acute Air Space Pneumonia (Acute Bacterial pneumonia) Acute air space pneumonia results from infection by bacteria that multipaly extracellulary in the alveoli. This evokes an acute inflammation with dilation of alveolar capillaries, exudation of fluid, and emigration of neutrophils in to the alveoli. The air spaces become filled with inflammatory exudates,causing the affected lung to become airless (consolidation). The peripheral blood commonly shows a neutrophil leukocytosis. Acute space pneumonias tend to spread to adjacent alveoli though direct intra-alveolar communications (the pores of Kohn). The facility with which organisms spread directly is a measure of their virulence; highly virulent organisms spread rapidly, causing large areas of lung to become affected, whereas less virulent agents tend to remain localized. Lobar Pneumonia In lobar pneumonia, the bronchi are not involved, and large confluent areas (sometimes entire lobes) consolidated (Figure 7-3).Lobar pneumonia is characterized by a large area of consolidafion on chest x-ray associated with air bronchograms that indicate absence of involvement of bronchi. Lobar pneumonia typically occurs with primary pneumonias caused by virulent agents, most commonly pneumococci. A. Etiology The most common cause of air space pneumonia is S. pneumoniae. This is overwhelmingly the case (60% - 70%) in primary community-acquired pneumonias of lobar pattern, with most of the remainder resulting from L. pneumophila. B, Pathologic Features Lobar pneumonia progresses through four stages: acute congestion, red hepatization, gray hepatization, and resolution. ~ Acute congestion is the early phase of infection, when the bacteria are multiplying in the alveoli and spreading to contiguous alveoli. The normal alveolar defenses have been overcome, and there is early injury to the alveoli. Alveal macropbages secrete mediators, and there is complement activation resulting in acute inflammation. There is active dilation of alveolar capillaries and early fluid exudation, neutrophil emigration, and erythmeyte diapedesis into the alveoli. Clinically, this stage corresponds to the onset of disease, with high fever and cough. Bacteremia is common. Involvement of the pleura is also conmmon and may result in chest pain, a pleural rub, and pleural effusion. ~ Red hepatization is characterized by lncreasing consulidation of the involved lung due to continued exudation and neutrophil emigration (Figure 7 4 ), Alveolar congestion is still present, and the alvcolur air has been replaced by the cellular exudate, red cells, neutrophils, and fibrin, etc. The basic alveolar architecture is maintained, although there is loss of lining cells. The lung lobe has a liver-like consistency, In most patients, the infection is controlled at this stage, either naturally or by antibiotic therapy, which eliminates the bacterium. ~ In gray hepatization, features of consolidation are present, but the infection has been controlled and there is neither hyperemia nor continued exudation and neutrophil emigration, while the fibrinous exudates persist within the alveoli. The lung is dry, gray and firm. The patient has usually recovered clinically. ~ Resolution. This stage represents the resorption of exadate and enzymatic digestion of inflammatory debris: the exudate is slowly removed and the alveo1ar injur) repaired.

7 Gray hepatization and resolution correspond to phases of healing, which can go on for several weeks until the lung returns to normal. C. Clinical Features Patients with lobar pneumnonia present with an acute onset of fever, dyspnea, and cough that is commonly productive of purulent, rust-colored sputum. Chest pain. a pleural friction rub, and effusion are present if there is pleural involvement. When secondary pneumonia occurs in chronically ill patients, these symptoms may not be obvious. Physical exmination may show evidence of consolidation. Chest x-ray to confirm an alveolar pattern of pneumonia is essential to differentiate air space pneumonia from interstitial pneumonia. Chest x ray may also differentiate between lobar and brochopneumonie patterns, which provides insight to the etiologic agent. Lobular Pneumonia (Bronchopneumonia) In bronchopneumonia, the bronchi are infected, with involvement of adjacent alveoli in a patchy, often limited fashion. Chest x-ray shows patchy consolidation with absent air bronchograms. Bronchopneumonia occurs typically in secondary pneumonia and is usually caused by less virulent agents. When bronchopnenmonia is the result of infection with a virulent agent, infection spreads through the pores of Kohn and becomes confluent, resulting in disease that is very similar to lobar pneumonia. A. Etiology In patients who develop secondary pneumonas of a bronchopneumonic pattern - many bacteria, such Staphylococcus aureus gram-negative bacilli, and H. influenzae as well as S. pneumoniae, can be involved. B. Pathologic Features Lobular pneumonia is characterized by foci of acute suppurative iuflammation centered on bronchioles. The consolidation may be patchy through one lobe but is more often multilobar and frequently bilateral and basal. Well-developed lesions are slightly elevated, dry, granular, gray-red to yellow, and poorly delimited at their margins. They vary in size up to 0.5 to 1 cm in diameter. Confluence of these foci occurs in the more florid instances, producing the appearance of total lobular consolidation ( confluent bronchopneumonia ). The lung substance immediately surroundinlg areas of consolidation is usually slightly hyperemic and edematous, but the large intervening areas are generally normal. Histologically. the reaction compliscs a suppurative exudate thai fills the bronchi, bronchioles, and adjacent alveolar spaces. Neutrophils are dominant in this exudation, and usually, only small amounts of fibrin are present. As expected, the abscesses are marked by necrosis of the underlyiug architecture. C, Clinical Features The clinical picture of lobular pneumonia is seldom as well defined as that of lobar pneumonia, largely be cause it is frequently overshadowed by the predisposing bondition. Moreover the many etiologic agents for this disease have a considerable range of virulence, and patients vary in vulnerability, In general, the onset is insidious; often appearing as a nonspecific worsening of the patient's prior condition, with low-grade fever and cough productive of punlent sputum. Respiratory difficulty is typically not prominent. The course is irregular, but resolution usually occurs if treatment is appropriate and the patient is not severely debilitated. The characteristic radio logic appearance of broncho pneumonia shows focal opacities, The area of affected Lung can be identified clinically by hearing crackles (crepitating) on auscultation.

8 Complications of Acute Air Space pneumonia A. Disturbances of Ventilation and Perfusion Air space pneumonia interferes with gas exchange in the involved area of the lung. There is no ventilation because the alveoli are filled with exudates, and perfusion is abnormal because of the micro circulatory changes of acute inflammation. In most cases, vital capacity is reduced, but respiratory; failure occurs only with extensive disease involving both lungs. B. Pleural Involvement Spread of infection to the pleura, with acute inflammation and effusion, commonly accompanies air space pneumonia. In most cases, this resolves with treatment of the pneumonia. Rarely, pleural inflammation becomes progressive and does not resolve, leading to loculation and accumulation of pus (enlpyenla). C. Bacteremia Baeteremia is the most serious complication of pneumoeoceal pneumonia. Its occurrence significantly increases the likelihood of death. Bacteremia may also lead to pneumococcal infections else-where in the body. most commonlly meningitis and endocarditis. D. Suppuration ( Abscess Formation) Suppuration is associated wilh liquefactive necrosis of alveoli leading to areas of destroyed lung replaced by pus. Suppuration is associated with virulent pyogenic bacteria such as s. aureus, gram-negative bacilli, and type 3 pneumococci. Suppuration is associated with a high incidence of treatment failure and death, in patients who recover, areas of suppuration heal by fibrous scarring because the destroyed alveoli cannot regenerate. E. Necrotizing Bacterial Pneumonia This is a rare complication characterized by extremely severe necrosis of the lung associated with a rapidly progressive disease with a high mortality rate. It is seen with etiologic agents such as Yersinia pestis (pneumonic plague ) and Bucillus anthracis (anthrax), which are rare causes of pneumonia. An acute necrotizing pneumonia may also occur in immunodeficient and malnourished patients secondary to more common pathogens such as L. pneumophila and M. tuberculosis. F. Pulmonary Camification Organization of tile excudate, which may convert a portion of the lung into solid tissue, known as pulmonary carnificafion. Viral pneumonia A. Etiology Most of the agents causing viral pneumonia are obligate intracellular organisms: Influenza and para influenza viruses commonly occur in epidomics; respiratory syncytial virus and adenovirus are the most common causes of sporadic viral pneunmonia in children and adults, respectively. cytomegalovirus and herpesviruses are important in immunocompromised patients. Pneumonia may accompany viral exanthems such as measles and chickenpox. B. Pathologic Features The alveolar septa are expanded by hyperemia, edema, and a cellular infiltrate composed of lymphocytes and plasma cells (Figure 7-6). The alveolar spaces are airfilled. The infected alveolar epithelial cells may show a variety of cytopathic effects such necrosis, the presence of inclusion bodies ( cytomegalovrus, herpesviruses, chlamydiae), and multinucleated giant cells (respiratory syncytial virus, measles, herpesviruses ), which may be useful in identifying the specific agent if

9 tissue biopsies are taken. C. Clinical Features Patients with viral pneumonia present with acute unit of fever, cough, and dyspnea. Cough is usually unproductive or produces mucoid sputum. The illness is usually mild and self-limited (walking pneumonia). Physical examination may show scattered rules due to associated bronchiolitis, but there is no evidence of consolidation. Chest x-ray shows the pattern of interstitial involvement that serveres to differentiate this disorder from air space pneumonia.pleural involvement does not occur. In most cases, patients are not seriously ill, and a specific etiologic diagnosis is not attempted because no specific therapy is indicated.

10 本次内容为病理学重点, 大叶性肺炎和小叶性肺炎均为临床常见 疾病 在首次进入呼吸系统的讲解时, 结合学生组织学已经淡忘 的特点, 为他们首先讲解了正常呼吸系统的组织及解剖学特点, 课后小结 便于他们进一步理解疾病的病理变化, 授课效果较好 授课教师 : 王琳