3. Contents of the training materials

Aetiology and pathogenesis of the disease.

Pneumonia is defined as an acute respiratory illness associated with recently developed radiological pulmonary shadowing which either is segmental or affects more than one lobe. As the setting in which a pneumonia develops has such major implications for the likely organisms involved and hence dictates the immediate choice of antibiotics, pneumonias are now classified as community-acquired, hospital-acquired, or those occurring in the immunocompromised host or damaged lung (including suppurative and aspirational pneumonia).

Common symptoms and signs of pneumonia include:

• cough

• fever

• pleuritic chest pain

Features which indicate the severity of the pneumonia include:

• confusion

• respiratory distress

• cyanosis

The classical physical signs of pneumonic lung consolidation are:

• reduced percussion note

• bronchial breathing

• crackles

• whispering pectoriloquy (Whispering pectoriloquy is the increased quality and loudness of whispers that are heard with a stethoscope over an area of lung consolidation

• pleural friction rub

Septicaemia should be suspected if the patient is cold, clammy and hypotensive.

Sputum production may not be a feature in the acute phase

Clinical classification of the PNEUMONIA

1. Community-acquired pneumonia

Typical:

S. pneumoniae, H. influenzae, S. aureus, M. catarrhalis, gram(-) aerobs, S. aeroginosa

2. Hospital-Acquired and Institutional-Acquired Pneumonia

Atypical:

M. pneumoniae, Legionella spp., C. pneumoniae

S. aureus, St. pneumoniae, P. aeroginosa, Klebsiella, Proteus, E. coli, enterobacters

3. Pneumonia in the immunocompromised patient

Bacteroides flagelis, Bac. melanogerucus, Fusobacterium nucleatum

4. Suppurative pneumonia and aspiration pneumonia

citomegalovirusis, fungi, Pneumocystis carm

The criteria for severe pneumonia

Small:

• respiratory rate 30/min and >

• confusion

• systolic BP less than 90 мм.рт.ст.

• SaО2<90%

• PaО2<60 мм.рт.ст.

• More than one lobe involved

Big:

• Need in Artificial Ventilation

• fast progression of infiltrative changes

• septic chock

• acute renal failure

1. Community-acquired pneumonia

This form of pneumonia is responsible for over 1 000 000 admissions per year in the UK. Infection is usually spread by droplet inhalation and, while most patients affected are previously well, cigarette smoke, alcohol and corticosteroid therapy all impair ciliary and immune function. Other risk factors include old age, recent influenza infection, pre-existing lung disease and, for certain forms of pneumonia, contact with sick birds (Chlamydia psittaci) or farm environments (Coxiella burnetii). Knowledge of the patient's recent travel history and local epidemics is also valuable. Appropriate investigation allows a microbiological diagnosis to be made in approximately 60% of patients with pneumonia. 'Lobar pneumonia' is a radiological and pathological term referring to homogeneous consolidation (red hepatisation) of one or more lung lobes, often with associated pleural inflammation; bronchopneumonia refers to more patchy alveolar consolidation associated with bronchial and bronchiolar inflammation often affecting both lower lobes. It is particularly common in winter in countries with temperate climates.

Eighty percent of community acquired pneumonia is pneumococcal pneumonia.

Other causes of community acquired pneumonias include haemophilus influenzae, staphylococcal aureus, atypical pneumonias (e.g. due to mycoplasma pneumoniae), mycobacterium tuberculosis, and viruses.

Clinical features

Patients present with a short illness of cough, fever and malaise, often associated with pleuritic chest pain which is occasionally referred to the shoulder or anterior abdominal wall. The cough is characteristically short, painful and at first dry, but later becomes productive and may become rust-coloured or even frankly blood-stained. The sudden onset of a high fever can result in rigors or, in children, vomiting or a febrile convulsion. Appetite is usually lost and headache is a frequent accompanying symptom. In patients with severe pneumonia confusion can be an early and dominant problem.

Physical signs include a significant pyrexia, tachycardia, tachypnoea, evidence of hypoxaemia and, not infrequently, hypotension and confusion. Pleurisy often results in diminution of respiratory movement and a pleural rub on the affected side. At a variable time after onset, generally within 2 days, signs of consolidation appear, with impairment of the percussion note and high-pitched bronchial breath sounds. When resolution begins, numerous coarse crepitations are heard, indicating liquefaction of the alveolar exudate. If a para-pneumonic pleural effusion develops, physical signs of fluid in the pleural space are usually found, but bronchial breath sounds can persist and the presence of an empyema may be suspected only from the recurrence or persistence of pyrexia. Upper abdominal tenderness is sometimes apparent in patients with lower lobe pneumonia or if there is associated hepatitis.

Investigations

The main objectives of investigating patients with a clinically based diagnosis of pneumonia are:

• to obtain a radiological confirmation of the diagnosis

• to exclude other conditions that may mimic pneumonia

• to obtain a microbiological diagnosis

• to assess the severity of the pneumonia

• to identify the development of complications.

Radiological examination

In lobar pneumonia, the chest radiograph shows a homogeneous opacity localised to the affected lobe or segment; this usually appears within 12-18 hours of the onset of the illness. Radiological examination is also particularly helpful if a complication such as pleural effusion, intrapulmonary abscess formation or empyema is suspected. Hilar lymphadenopathy is occasionally seen in mycoplasma pneumonia, and lung cavities are more frequently observed in patients with staphylococcal or pneumococcal serotype 3 pneumonia. Follow-up radiological examination is essential as failure of a pneumonia to resolve may indicate underlying bronchial obstruction (e.g. a foreign body or carcinoma)

Microbiological investigations

Every effort should be made to establish a microbiological diagnosis, as such information is invaluable in tailoring antibiotic therapy and in managing any complications. The identification of organisms such as Legionella pneumophila also has important public health implications. Rapid results can sometimes be obtained with 'bedside' complement fixation tests for antigen levels (for example, of H. influenzae and Pneumocystis carinii) in urine and other body fluids. In patients who are severely ill a microbiological diagnosis becomes essential and, if sputum cannot be obtained, an attempt should be made to aspirate secretions or washings from the trachea or lower respiratory tract either by bronchoscopy or by inserting a needle through the cricothyroid membrane. Some patients can be induced to produce sputum by the administration of nebulised hypertonic saline.

Arterial blood gas measurements

These should be measured in all patients admitted to hospital with a diagnosis of pneumonia.

General blood tests

A high neutrophil leucocytosis favours a diagnosis of bacterial (particularly pneumococcal) pneumonia; patients with pneumonia caused by atypical agents tend to have a marginally raised or normal white cell count. A marked leucopenia indicates either a viral aetiology or an overwhelming bacterial infection.

Assessment of disease severity

It is essential that in every patient with a clinical diagnosis of pneumonia an assessment is made to determine the severity of the disease. The use of simple clinical and laboratory parameters can determine very accurately those at high risk of death and forms an important guide to the level of patient monitoring required. This assessment also has an important bearing on antibiotic choice.

C omplications:

Medical Care:

Oxygen should be administered to all hypoxaemic patients, and high concentrations (≥35%) should be used in all patients who do not have hypercapnia associated with advanced COPD. Assisted ventilation should be considered at an early stage in all patients who remain significantly hypoxaemic despite adequate oxygen therapy. Most patients with moderate to severe pneumonia also require intravenous fluids and occasionally inotrope support

Antibiotics should be given as soon as a clinical diagnosis of pneumonia is made. If possible, culture specimens should be sent prior to starting antibiotics but such treatment should not be delayed if, for example, a sputum sample is not readily available. In most cases of uncomplicated pneumococcal pneumonia a 7-10-day course of treatment is usually adequate, although treatment is usually required for 14 days or longer in patients with Legionella, staphylococcal or Klebsiella pneumonia.

penicillins
ampicillin	0,5-1,0-2,0		6-8 час.		в/м
amoxicillin	0,5-1,0		8 час.		per os
amoxiqlave	0,5-1,0 0,375-0,625 1,2		8-12 час. 8 час. 6-8 час.		в/м, в/в per os в/в
piperacillin	0,1-0,3 г/кг		6-12 час.		в/в, в/м
oxacillin	0,75		4-6 час.		per os, в/м, в/в
cephalosporins
cefasolin, I	0,5-2,0		8 час.		в/м, в/в
cefalotin, I	0,5-2,0		4-6 час.		в/м, в/в
Cefamandol, II	0,5-1,0		4-8 час.		в/м, в/в
cefuroxim, II	0,75-1,5		8 час.		в/м, в/в
cefotaxim, III	1,0-1,5		6-12 час.		в/м, в/в
ceftriaxon, III	1,0-2,0		12 час.		в/м, в/в
Fluoroquinolones
ciprofloxacin		0,5 0,2-0,4		12 час. 12 час.		per os в/в
ofloxacin		0,2		12 час.		per os
pefloxacin		0,4		12 час.		per os, в/в
levofloxacin		0,5		12-24 час.		per os в/в
tetracyclins
Doxycycline	0,2 0,1		І день след. дни		per os

Formal physiotherapy is not indicated in patients with community-acquired pneumonia; however, assisted coughing is important in patients who suppress cough because of pleural pain. The administration of analgesic drugs should be coordinated with this form of physiotherapy to optimise patient cooperation.

HOSPITAL-ACQUIRED PNEUMONIA

Hospital-acquired or nosocomial pneumonia refers to a new episode of pneumonia occurring at least 2 days after admission to hospital. The term includes post-operative and certain forms of aspiration pneumonia, and pneumonia or bronchopneumonia developing in patients with chronic lung disease, general debility or those receiving assisted ventilation.

Aetiology

The factors predisposing to the development of pneumonia in a hospitalised patient are listed in Box 13.47. The elderly are particularly at risk and this condition now occurs in 2-5% of all hospital admissions

The most important distinction between hospital- and community-acquired pneumonia is the difference in the spectrum of pathogenic organisms, with the majority of hospital-acquired infections caused by Gram-negative bacteria. These include Escherichia, Pseudomonas and Klebsiella species. Infections caused by Staph. aureus (including multidrug-resistant-MRSA-forms) are also common in hospital, and anaerobic organisms are much more likely than in pneumonia acquired in the community. This profile of organisms in part reflects the high rate of colonisation of the nasopharynx of hospital patients with Gram-negative bacteria, together with the poor host defences and general inability of the severely ill or semiconscious patient to clear upper airway and respiratory tract secretions.

Clinical features

The clinical features and investigation of patients with hospital-acquired pneumonia are very similar to community-acquired pneumonia (see pp. 526-528). In the elderly or debilitated patient who develops acute bronchopneumonia (or 'hypostatic pneumonia') symptoms of acute bronchitis are followed after 2 or 3 days by increased cough and sputum purulence associated with a rise in temperature. Breathlessness and central cyanosis may then appear, but pleural pain is uncommon. In the early stages the physical signs are those of acute bronchitis followed by the development of crepitations. There is a neutrophil leucocytosis and the chest radiograph shows mottled opacities in both lung fields, chiefly in the lower zones.

Management

Adequate Gram-negative coverage is usually obtained with:

- third-generation cephalosporin (e.g. cefotaxime) plus an aminoglycoside (e.g. gentamicin)

imipenem or

- monocyclic β-lactam (e.g. aztreonam) plus flucloxacillin.

Physiotherapy is of particular importance in the immobile and elderly, and adequate oxygen therapy, fluid support and monitoring are essential. The mortality from hospital-acquired pneumonia is high (approximately 30%).

ASPIRATIONAL PNEUMONIA

More frequently, aspiration pneumonia develops after the inhalation of septic material during operations on the nose, mouth or throat under general anaesthesia, or of vomitus during anaesthesia or coma. Additional risk factors for aspiration pneumonia include bulbar or vocal cord palsy, achalasia or oesophageal reflux and alcoholism. Aspiration into the lungs of acid gastric contents can give rise to a severe haemorrhagic pneumonia often complicated by the acute respiratory distress syndrome (ARDS).

Aspiration pneumonia can be treated with co-amoxiclav 1.2 g 8-hourly plus metronidazole 500 mg 8-hourly. The nature and severity of most hospital-acquired pneumonias dictate that these antibiotics are all given intravenously, at least initially

Type of pneumonia	Drugs
Aspirational pneumonia	Aminoglycosides or Cephalosporins ІІІgen.+Metronidazole orClindamycin Aminoglycosides + β-lactams / inhibitors of β-lactamaz or Clindamycin

PNEUMONIA IN THE IMMUNOCOMPROMISED PATIENT

Pulmonary infection is common in patients receiving immunosuppressive drugs and in those with diseases causing defects of cellular or humoral immune mechanisms. For example, patients with AIDS are susceptible to many types of pneumonia, in particular Pneumocystis carinii (see p. 120). It is important to recognise, however, that the common pathogenic bacteria are responsible for the majority of lung infections in immunocompromised patients (see Box 13.48). Despite this, the Gram-negative bacteria, especially Pseudomonas aeruginosa, are more of a problem than Gram-positive organisms, and unusual organisms or those normally considered to be of low virulence or non-pathogenic may become 'opportunistic' pathogens. Likewise, infection is often due to more than one organism. Pneumocystis carinii and other fungi such as Aspergillus fumigatus, viral infections, cytomegalovirus, herpesviruses, and infections with M. tuberculosis and other types of mycobacteria are all common causes of infection in patients who are immunocompromised.

Clinical features

The patient usually presents with fever, cough, breathlessness and infiltrates on the chest radiograph. Patients may develop non-specific symptoms, and a high index of suspicion is required to determine the site and nature of the infection. In general, the onset of symptoms tends to be less rapid in patients with opportunistic organisms such as Pneumocystis carinii and mycobacterial infections. In Pneumocystis carinii pneumonia symptoms of cough and breathlessness can be present several days or weeks before the onset of systemic symptoms or even a chest radiograph abnormality.

Management

Whenever possible, treatment should be based on an established aetiological diagnosis. In practice, however, the cause of the pneumonia is frequently not known when treatment has to be started. Hence, broad-spectrum antibiotic therapy is required (e.g. a third-generation cephalosporin, or a quinolone, plus an antistaphylococcal antibiotic, or an antipseudomonal penicillin plus an aminoglycoside) and this treatment is thereafter tailored according to the results of investigations and the clinical response.

Agent	Drugs
Virus	Acyclovir, guncyclovir
Pneumocysta carinii	Trimethoprim-sulfamethoxazole
Fungi	Cetoconazol, fluconazol, voriconazol, itraconazol

• Streptococcus pneumoniae (pneumococcus)

  • Penicillin

  • Amoxicillin

  • Cephalosporins

  • Erythromycin

  • Azithromycin

  • Clarithromycin

  • Fluoroquinolones

• Haemophilus influenzae

  • Cephalosporins (2nd and 3rd generation)

  • Amoxicillin-clavulanate

  • Azithromycin

  • Fluoroquinolones

  • Trimethoprim-sulfamethoxazole

• Legionella pneumophila

  • Erythromycin (with or without rifampin)

  • Azithromycin

  • Fluoroquinolones

• Mycoplasma pneumoniae

  • Erythromycin

  • Doxycycline

  • Azithromycin

  • Clarithromycin

  • Fluoroquinolones

• Chlamydia pneumoniae

  • Erythromycin

  • Doxycycline

  • Azithromycin

  • Clarithromycin

  • Fluoroquinolones

• Staphylococcus aureus

  • Cephalosporins (1st generation)

  • Nafcillin

  • Oxacillin

  • Vancomycin

• Anaerobic bacteria

  • Clindamycin

  • Metronidazole

• Gram-negative bacteria

  • Imipenem

  • Cephalosporins (3rd and 4th generation)

  • Aminoglycosides

  • Fluoroquinolones

  • Newer fluoroquinolones

  • levofloxacin, monifloxacin, gatifloxacin

4. Plan and organizational structure of educational sessions on discipline.

№ з/п	Stages of class	Time distribu-tion	Types of control	Equipment training
1.	The starting phase	15%
1.1.	Organizational matters	20-25 min.
1.2.	Formation of motivation
1.3.	Control of entry-level training		─ written computer testing; ─ oral questioning by the standardized list of questions.	─ textbooks treatment of internal diseases; ─ guidelines; ─ situational problem in therapy of internal medicine; ─ tests "Step 2";
2.	The main stage ─ demonstration of the patient - his clinical examination (history, physical examination, additional methods of investigation); ─ interpretation received symptoms	65% 120-130 mn.	─ practical skills at the bedside (collecting complaints, history of illness, physical examination, assessment of results of additional methods investigation); ─ interpretation of the results.	─ themed patients.
3.	The final stage	20%
3.1.	Control of the final level of training	25-30 min.	─ situational tasks; ─ structured written work.
3.2.	The total score of student workload
3.3.	Informing students about the topic the next lesson