Saturday 2 November 2013

PNEMONIA

                                           Pneumonia.
 Pneumonia (P) is one of the most wide-spread disease of human. In spite of wide prevalence of P, knowledge of modern methods of diagnostics and treatment of disease are not enough.
PNEUMONIA - is acute infectious disease, mainly bacterial etiology, which causes the air sacs in the lungs (called the alveoli), and the smaller bronchial tubes to become inflamed and fill with fluid. From data of official statistics in Ukraine in 2005, morbidity of adults of P. was 4,26 on 1000 population, and death rate – 13,5 % per 100 thousand persons, it means that  about 3,2 % of all people who developed pneumonia subsequently died from the infection.  
Etiology.
Many different organisms can cause P, including bacteria (Str. Pneumoniae, Staf. pyogenus, Staf. albus, Klebsiella pneumoniae is a pneumobacillus, Neisseria cataralis, Proteus vulgaris, Haemophilus influenzae, Psevdomonas aeruginosa, Legionella pneumophilia,, Micoplasma pneumoniae,, Bacteroides fragilis), the viruses of Citomegalovirus, and fungi of Candida albicans. Pneumonia can range from mild to severe. The severity depends on the type of organism causing pneumonia, as well as your age and underlying health.
The basic patogenetic links of development of pneumonia are:
- penetration of infection in pulmonary tissue  (by inhalation, bronchogenic  way, hematogenic way – at a sepsis, direct distribution of infection in lungs from nearby organs, lymphogenic way).
- a change of the system of local bronchopulmonary protection -the state of mucociliary transport, bronchopulmonary immune system, factors of unspecific resistance (lysozyme , lactoferrin, IGA, interferon, system of surfactant),
- development of local inflammatory process and his distribution on pulmonary tissue , that depends on the type of infection:
Str. Pneumoniae, Klebsiella pneumoniae, Haemophilus influenzae and E. coli producing endotoxins   and during  persistence in air-cells  they cause a serosal edema. This serosal edema  is their reproducing environment and  helps them to penetrate through the Kon’s  pores to nearby  air-cells. In such way segmentary and croupous pneumonias are  developed.
Streptococci, staphylococcuss producing exotoxins, which promote  limitation of inflammation by fibrin,  and smaller bronchial tubes  to become inflamed and fill with fluid with formation of microatelectasis. In such way focal pneumonia is  developed.
Production by leucocytes and epithelial  cells bioactive substances (cytokines) plays important role in development of inflammation. Cytokines influence on chemotaxis of macrophages, neutrophils and other cells, which are taking part in local inflammatory reaction.
Classification
Select the followings types of pneumonias:
·       community-acquired pneumonia
·        nosocomial or hospital-acquired pneumonia
·       Aspiration pneumonia
·       Pneumonia in an immunocompromised host
Pneumonia that develops outside the hospital setting is considered community-acquired pneumonia. Pneumonia developing 72 hours or more after admission to the hospital is termed nosocomial or hospital-acquired pneumonia. Pneumonia can be mild, moderate and severe.
Severe P. is the special form of disease of different etiology, which shows up a heavy intoxication syndrome, haemodynamic changes, expressed respiratory insufficiency and signs of septic shock.
Recommend to select the large and small criteria of severe pneumonia.
SMALL CRITERIA :
- breathing frequency 30 in 1 mins and more,
- unconsciousness, - pressure of oxygen below 60 ,
- a systole arterial blood pressure below 90
- bilateral or polifocal defeat, cavities of disintegration, pleura effusion.

LARGE CRITERIA:
           -  requirement of artificial ventilation of lungs,
- rapid progress of focal infiltration, infiltration more than on 50% during the nearest 2 days,
-                      septic shock or necessity of introduction of vasopressor  medicines during 4 hours and more. We can say about severe P. if we have 2 small and 1 large criteria. In such cases must be immediate hospitalization.
M. pneumoniae is a common cause of mild pneumonia that usually affects people younger than 40. Various studies suggest that it causes 15-50% of all pneumonia in adults and an even higher percentage of pneumonia in school-aged children.
People at highest risk for mycoplasma pneumonia include those living or working in crowded areas such as schools and homeless shelters, although many people who contract mycoplasma pneumonia have no identifiable risk factor.
The symptoms are generally mild and appear over a period of 1 to 3 weeks. They may become more severe in some people.
Common symptoms include the following:
Headache, fever (may be high),Chills, excessive sweating, Cough (usually dry and without phlegm or blood), chest pain, sore throat
Less frequently seen symptoms include:
A physical examination may reveal enlarged lymph nodes and inflammation of the eardrum. An examination of the chest with a stethoscope (auscultation) reveals crackles.
Legionella pneumophila.
Most infection occurs in middle-aged or older people, although it has been reported in children. Typically, the disease is less severe in children. Symptoms tend to get worse during the first 4 to 6 days. They typically improve in another 4 to 5 days.
Symptoms may include:
  • Muscle aches and stiffness
  • Joint pain
  • Loss of energy
  • General discomfort, uneasiness, or ill feeling (malaise)
  • Headache
  • Fever
  • Shaking chills
  • Nonproductive cough
  • Coughing of blood
  • Shortness of breath
  • Chest pain,
  • Diarrhea
Chlamydophila pneumonia occurs year round and accounts for 5-15% of all pneumonias. It is usually mild with a low mortality rate.

Community acquired pneumonia

Community-acquired pneumonia develops in people with limited or no contact with medical institutions or settings. The most commonly identified pathogens are Streptococcus pneumoniae , Haemophilus influenzae , and atypical organisms (ie, Chlamydia pneumoniae , Mycoplasma pneumoniae , Legionella sp). Symptoms and signs are fever, cough, dyspnea, tachypnea, and tachycardia. Diagnosis is based on clinical presentation and chest x-ray. Treatment is with empirically chosen antibiotics. Prognosis is excellent for relatively young and/or healthy patients, but many pneumonias, especially when caused by S. pneumoniae and influenza virus, are fatal in older, sicker patients.
Symptoms and Signs
Symptoms include malaise, cough, dyspnea, and chest pain. Cough typically is productive in older children and adults and dry in infants, young children, and the elderly. Dyspnea usually is mild and exertional and is rarely present at rest. Chest pain is pleuritic and is adjacent to the infected area. Pneumonia may manifest as upper abdominal pain when lower lobe infection irritates the diaphragm. Symptoms become variable at the extremes of age; infection in infants may manifest as nonspecific irritability and restlessness; in the elderly, as confusion and obtundation.
Symptoms and signs were previously thought to differ by type of pathogen, but presentations overlap considerably. In addition, no single symptom or sign is sensitive or specific enough to predict the organism. Symptoms are even similar for noninfective lung diseases such as pulmonary embolism, pulmonary malignancy, and other inflammatory lung diseases.
Diagnosis
The most important diagnostic tool for pneumonia is the stethoscope. Sounds in the chest that may indicate pneumonia include:
-                      Rales, a bubbling or crackling sound. Rales on one side of the chest or that are heard while the patient is lying down strongly suggest pneumonia.
-                      Abnormal rumblings indicating that there is sputum in the large airways.
-                      A dull thud. The physician will use a test called percussion, in which the chest is tapped lightly. A dull thud, instead of a hollow drum-like sound, indicates certain conditions that suggest pneumonia. These conditions include consolidation (in which the lung becomes firm and inelastic) and pleural effusion (fluid build-up in the space between the lungs and the lining around it).

Diagnosis is suspected on the basis of clinical presentation and is confirmed by chest x-ray .Chest x-ray almost always demonstrates some degree of infiltrate; rarely, an infiltrate is absent in the first 24 to 48 h of illness. In general, no specific findings distinguish one type of infection from another, though multilobar infiltrates suggest S. pneumoniae or Legionella pneumophila infection, and interstitial pneumonia suggests viral or mycoplasma etiology.In severe cases, a doctor needs to use invasive diagnostic measures to identify the cause of the infection. Standard lab tests used to help diagnose pneumonia include:
Sputum Tests. The color of the mucus (sputum) sample coughed up from the lungs can reveal the severity of the disease. Only a sputum sample will reveal the organism causing the infection.The patient coughs as deeply as possible to bring up mucus from the lungs, since a shallow cough produces a sample that usually only contains normal mouth bacteria. Some people may need to inhale a saline spray to produce an adequate sample. In some cases, a tube will be inserted through the nose into the lower respiratory tract to trigger a deeper cough.
The physician will check the sputum for:
-                      Blood, which means an infection is present.
-                      Color and consistency: If it is yellow, green, or brown, an infection is likely.
The sputum sample is sent to the laboratory, where it is analyzed for the presence of bacteria and to determine whether the bacteria are Gram-negative or Gram-positive.
Blood Tests. The following blood tests may be performed:
-                      White blood cell count (WBC). High levels indicate infection.
-                      Blood cultures. Cultures are done to determine the specific organism causing the pneumonia, but they usually cannot distinguish between harmless and dangerous organisms. They are accurate in only 10 - 30% of cases. Their use is generally limited to severe cases.
-                      Detection of antibodies to S. pneumoniae. Antibodies are immune factors that target specific foreign invaders. One type of immunohistochemical test for S. pneumoniae is showing tremendous promise. The presence of antibodies that are responding to mycoplasma or chlamydia infection are not present early enough in the course of pneumonia to allow for prompt diagnosis and treatment.
Patients with CAP can be categorized into 1 of 4 groups based on information collected at the time of the initial evaluation. The risk factors for stratification include the need for hospitalization, the severity of illness, the presence of coexisting disease, and the patient's age. The 4 major categories not only speculate the microbial etiology but also predict ultimate prognosis and outcome. These categories are
(1) CAP occurring in patients aged 60 years or younger who have no evidence of comorbidity and who can be treated in an outpatient setting,
(2)  CAP occurring in patients with evidence of comorbidity and/or who are aged 60 years or older who can be treated in an outpatient setting,
(3) CAP requiring hospitalization but not admission to an intensive care units (ICU),
(4) severe CAP requiring ICU care.
Treatment
Because organisms are difficult to identify, antibiotics are selected based on likely pathogens and severity of illness
A/b for empiric treatment, divide into medicines of the first choice (medicines of  1 choice and alternative medicines) and second row.
                                  

EMPIRIC ANTIBAKTERIAL THERAPY
PATIENTS OF CAP IN AMBULATORY

Group of patients

Possible exciter
Antibiotic
first row

Antibiotic of the second row

Drugs of
choice
Alternative Drugs
1 group
(with the unsevere CAP, without concomitant pathology and other modifying factors
M. pneumoniae
S. рneumoniae
H. influenzae
Peroral
reception: amoxycillin
or macrolide

Peroral reception:
fluoroquinolones
III-IV generation
Peroral reception:
1. Makrolide or doxycycline at uneffectiveness of aminopenicillin
2. Aminopenicillin or fluoroquinolones III-IV  generation at uneffectiveness of macrolide
11 group
With the unsevere CAP, with the presence of concomitant pathology or other modifying factors

M. pneumoniae
S. рneumoniae
H. influenzae
S. aureus
M. catarrhalis
family
Enterobacteriaceae
A peroral reception is amoxycillin or cefuroxym ethanol
Peroral reception: fluoroquinolones

III-IV generation
Or
Ceftriakson
Peroral reception:
To add to в-lactam macrolide or
monotherapy
Fluoroquinolones
III-IV generation
Note: * - parenterally introduction of Ceftriakson is appointed at impossibility of peroral reception of preparations of choice.       
  Estimation of efficiency of  antibacterial therapy is conducted in 48 hours from the beginning of treatment.
Duration of antibacterial therapy:
For patients with the unsevere CAP antibacterial   therapy can be completed after achievement of normalization of temperature during 3-5 days. As a rule in such cases treatment takes 7-10 days.
Criteria of efficiency of antibacterial therapy
- Temperature of body below 37,5
- absence of symptoms of intoxication,
- absence of signs of respiratory failure (breathing frequency below 20 in 1 mins),
- absence of festering sputum,
- there is a less than amount of leucocytes in blood, neutrocytes less than 80%, young forms –less 6%,
- absence of negative dynamics from data of roentgenologic research.
If  patient saved high temperature of body, intoxication or symptomatology makes progress, treatment is considered ineffective,  and it is necessary to  change antibacterial therapy to the antibiotic of the second row . U should remember some sings that are not necessary to change therapy.
Clinical signs and states which are not necessary to change  therapy
or make  its modifications
Clinical sign

 temperature of body of 37,0-37,5оС
In absence  of other signs of bacteria infection can be the sign of non-bacterial inflammation, postinfectious asthenia, medicinal fever

Maintainance of remaining changes on a x-rays (infiltration, increasing of pulmonary vasculature)
Can be saved during 1-2 months and more after carried P

(a roentgenologic dynamics is carried out more slowly, for 60% patients regress in the first 4 weeks. and these information can not be criteria for determination of duration of à/b therapy)
Dry cough
Can be saved during 1-2 months.

Maintainance of wheezes during auscultation
Dry wheezes can be saved during 3-4 weeks and more

Increase of erythrocyte sedimentation rate, ESR
Heterospecific index, is not only the sign of bacteria infection

Weakness, sweating
Displays of postinfectious asthenia

It is necessary to conduct differential diagnosis with the empyema of pleura, cancer of lungs, tuberculosis.

Empiric à/b therapy of patients of CAP in the hospital.
To the patients 1 and 2 groups which are hospitalized on social testimonies, appoint the proper à/b therapy.
To the patients 3 groups must be appointed the combined à/b therapy with the parenterally setting of preparations.
Antibacterial THERAPY OF PATIENTS with CAP IN HOSPITAL


Group of patients

Possible exciter
Antibiotic
first row

Antibiotic of the second row

Preparation
choice
Alternative preparation
3
group
(with the unsevere CAP)
S. рneumoniae
H. influenzae,
Atipichnye exciters,
Gramnegativnye
enterobacteria
Application of intravenous introduction or intramuscular introduction of: protected
aminopenicillin + macrolide (per os)
          or cephalosporin II- IIIgenerations + macrolide (per os)
Intravenous application: Fluoroquinolones
III-IV generation
Intravenous application of Fluoroquinolones III-IV generation or carbapenems
IV
group

with  severe CAP
S. рneumoniae
H. influenzae
S. aureus,
Legionella spp.,
Polimikrobnye associations
 intravenous introduction of protected
aminopenicillin + macrolide
          or cephalosporin III
generations + macrolide
Intravenous application: Fluoroquinolones
III-IV generation + в-lactam
Intravenous application of Fluoroquinolones III-IV generation + carbapenems
     Or carbapenems
+
Macrolide

At suspicion on
P. aeruginosa
cephalosporin
III-IV + aminoglycoside + cyprofloxaciny
Intravenous application: cephalosporin
III-IV  generation + aminoglycoside + Macrolide
Intravenous application
Meropenem
+ aminoglycoside +cyprofloxaciny

Estimation of efficiency – on those criteria in 48-72 hours  from the beginning of therapy.
Duration of à/b therapy – at treatment of patients with the severe CAP– 10 days. In this term mark disappearance of leukocytosis .
For patients with an early adequate clinical answer for à/b therapy  it is possible to change parenterally injection  to taking antibiotics per os.. In default of answer for treatment during the first  3 days it’s necessary  make the correction of treatment and additional inspection.
COMPLICATIONS OF NP
- pleura effusion,
- empyema of pleura,
- destruction / abscess of pulmonary tissue ,
- acute respiratory failure,
- infectious toxic shock,
- pericarditis, myocarditis..
Risk factors:
- age more  50 years
- concomitant diseases
- severe pneumonia,
-smoking.

Hospital-acquired pneumonia (HAP) or Nosocomial pneumonia
refers to any pneumonia contracted within 48-72 hours of being admitted in hospital. In practice, hospital-acquired pneumonia is often suspected on the basis of the appearance of a new infiltrate on a chest x-ray.
Classification
Select:
Early HAP – arises up during the first 5 days from the moment of hospitalization and  caused by  infection which patient had before hospitalization -S. Rneumoniae, H. Influenzae, methicillinsensetive S. aureus and other representatives of normal microflora of cavity of mouth. More frequent these agents are sensible to antibiotic drugs, and pneumonia has more favourable prognosis.
Late – develops not earlier 6 day of hospitalization and caused actually  by hospital microflora with more high risk of development of high-virulent and polyresistant bacterias, such as P. Aeruginosa, Enterobacteriaceae,  methicillinresistant culture of S. aureus. Such HAP has a less favourable prognosis.

Risk factors:
 Endotracheal intubation with mechanical ventilation poses the greatest overall risk; ventilator-associated pneumonia constitutes > 85% of all cases, with pneumonia occurring in 17 to 23% of ventilated patients. Endotracheal intubation breaches airway defenses, impairs cough and mucociliary clearance, and facilitates microaspiration of bacteria-laden secretions that pool above the inflated endotracheal tube cuff. In addition, bacteria form a biofilm on and within the endotracheal tube that protects them from antibiotics and host defenses.
In nonintubated patients, risk factors include previous antibiotic treatment, high gastric pH (from stress ulcer prophylaxis therapy), and coexisting cardiac, pulmonary, hepatic, and renal insufficiency. Major risk factors for postoperative pneumonia are age > 70, abdominal or thoracic surgery, and dependent functional status.