Medical brain notes 15

  CONGENITAL CYSTIC LUNG LESIONS The 2 most common malformations of the lung are  congenital cystic adenomatoidmalformation  (CCAM) and  bronchopulmonary sequestration  (BPS). CCAM is ahamartomatous lesion, and BPS is a nonfunctioning bronchopulmonary segment separate from the tracheobronchial tree. These conditions are followed by serial ultrasonography. Some resolve spontane-ously, though minimally invasive surgery may be required.

  ATELECTASIS Atelectasis  refers to an area of collapsed or nonexpanded lung. It is reversible, butareas of atelectasis predispose for infection due to decreased mucociliary clearance. The major types are as follows : ·              Obstruction/resorption atelectasis  is collapse of lung due to resorption ofair distal to an obstruction; examples include aspiration of a foreign body, chronic obstructive pulmonary disease (COPD), and postoperative atelectasis.   ·              Compression atelectasis  is atelectasis due to fluid, air, blood, or tumor in thepleural space.   ·              Contraction (scar) atelectasis  is due to fibrosis and scarring of the lung.   ·              Patchy atelectasis   is due ...

  PULMONARY INFECTIONS   In  bacterial pneumonia,  acute inflammation and consolidation (solidification) of the lung are due to a bacterial agent. Clinical signs and symptoms include fever and chills; productive cough with yellow-green (pus) or rusty (bloody) sputum; tachypnea; pleuritic chest pain; and decreased breath sounds, rales, and dullness to percussion. Studies typically show elevated white blood cell count with a left shift (an increase in immature leukocytes). Chest x-ray for lobar pneumonia typically shows lobar or segmental consolidation (opacification), and for bronchopneumonia typically shows patchy opacification. Pleural effusion may also be picked up on chest x-ray. In general, the keys to effective therapy are identification of the organism and early treatment with antibiotics. Lobar pneumonia  is characterized by consolidation of an entire lobe. The infect-ing organism is typically  Streptococcus pneumoniae  (95%) or  Klebsiella...

  SARCOIDOSIS Sarcoidosis  is a systemic granulomatous disease of uncertain etiology. The diseaseaffects females more than males, with typical age 20–60. It is most common in African American women. Clinical presentation varies. It may be asymptomatic, or presenting symptoms may include cough and shortness of breath; fatigue and malaise; skin lesions; eye irritation or pain; and fever or night sweats. Most often, the disease is first detected on chest x-ray as bilateral hilar lymphadenopathy or parenchymal infiltrates. The noncaseating granulomas that are characteristic of sarcoidosis may occur in  anyorgan of the body . In the lung, they typically form diffuse scattered granulomas;lymph node involvement may cause hilar and mediastinal adenopathy. Skin, liver and/or spleen, heart, central nervous system, bone marrow, and gastrointestinal tract are also frequent targets of the disease. Eye involvement can be seen in Mikulicz syndrome (involvement of the uvea and parotid). ...

  OBSTRUCTIVE PULMONARY DISEASE Chronic obstructive pulmonary disease (COPD)  is a general term used to indicatechronic decreased respiratory function due to chronic bronchitis or emphysema. Both diseases are associated with smoking. Chronic bronchitis   is a clinical diagnosis made when a patient has a persistent coughand copious sputum production for at least 3 months in 2 consecutive years. It is highly associated with smoking (90%). Clinical findings include cough, sputum production, dyspnea, frequent infections, hypoxia, cyanosis, and weight gain. Microscopic examination demonstrates hypertrophy and hyperplasia of bronchial mucous glands (Reid index equals the submucosal gland thickness divided by the bronchial wall thickness between the pseudostratified columnar epithelium and the perichondrium; normal ratio is ≤0.4). Complications include increased risk for recurrent infections; secondary pulmonary hypertension leading to right heart failure (cor pulmonale) and lun...

  INFILTRATIVE RESTRICTIVE LUNG DISEASES(DIFFUSE INTERSTITIAL DISEASES) Acute respiratory distress syndrome (ARDS)   refers to diffuse damage of alveolarepithelium and capillaries, resulting in progressive respiratory failure that is unre-sponsive to oxygen treatment. Clinicians use the term  ARDS , while pathologists use the term  diffuse alveolar damage (DAD)  to describe the pathologic changes. ARDS may be caused by shock, sepsis, trauma, gastric aspiration, radiation, oxygen toxicity, drugs, or pulmonary infection. Activated neutrophils mediate cell damage. Clinically, patients show dyspnea, tachypnea, hypoxemia, cyanosis, and use of acces-sory respiratory muscles. X-rays show bilateral lung opacity (“white out”). On gross pathologic examination affected lungs are heavy, stiff, and noncompli-ant. Microscopically, there is intra-alveolar edema, and hyaline membranes line the alveolar spaces. In resolving cases there is proliferation of type II pneumocytes and...