PNEUMONIA affects 156 million children under the age of 5 yrs across the globe,& is the leading cause of mortality in this age group.more than 2 million annual deaths are estimated to occur because of pneumonia in under 5 children,&almost all these occur in developing countries.It kills more children in this age groupthan AIDS,malaria &,measles combined.India carries largest burden of disease & deaths because of pneumonia,accuonting for 43million cases & 0.4million deaths.Fortunately most of deaths attributed to pneumonia can be prevented by relateively inexpensive strategies.An increasing focus on the scaling up of interventions for appropriate management of childhood pneumonia is crucial to achieve the Mellenium Development Goal of"reducing by two-third betwen 1990 & 2010,the under 5 mortality rate.

DEFINITION- Pneumonia is an abnormal inflammatory condition of the lung.It is often characterized as including inflammation of the parenchyma of the lung (that is, the alveoli) and abnormal alveolar filling with fluid (consolidation and exudation).

CONTENTS- [1] Classification a) Early classification schemes b) Combined clinical classification c) Community-acquired d) Hospital-acquired e) Other types of pneumonia.

[2] Signs and symptoms.

[3] Cause a) Viruses b) Bacteria c) Fungi d) Parasites e) Idiopathic.

[4] Diagnosis a) Investigations b) Combining findings

[5] Prevention

[6] Treatment a) Bacterial b)Viral

[7] Complications a) Respiratory and circulatory failure b)Pleural effusion, empyema, and abscess [8] Prognosis

CLASSIFICATION-Pneumonia can be classified in various ways- a) Early classification schemes Initial descriptions of pneumonia focused on the anatomic or pathologic appearance of the lung, either by direct inspection at autopsy or by its appearance under a microscope.

1) A lobar pneumonia is an infection that only involves a single lobe, or section, of a lung. Lobar pneumonia is often due to Streptococcus pneumoniae (though Klebsiella pneumoniae is also possible.)

2) Multilobar pneumonia involves more than one lobe, and it often causes a more severe illness.

3) Bronchial pneumonia affects the lungs in patches around the tubes (bronchi or bronchioles).

4) Interstitial pneumonia involves the areas in between the alveoli, and it may be called "interstitial pneumonitis." It is more likely to be caused by viruses or by atypical bacteria.

b)Combined clinical classification Traditionally, clinicians have classified pneumonia by clinical characteristics, dividing them into "acute" (less than three weeks duration) and "chronic" pneumonias. This is useful because chronic pneumonias tend to be either non-infectious, or mycobacterial, fungal, or mixed bacterial infections caused by airway obstruction. Acute pneumonias are further divided into the classic bacterial bronchopneumonias (such as Streptococcus pneumoniae), the atypical pneumonias (such as the interstitial pneumonitis of Mycoplasma pneumoniae or Chlamydia pneumoniae), and the aspiration pneumonia syndromes. Chronic pneumonias, on the other hand, mainly include those of Nocardia, Actinomyces and Blastomyces dermatitidis, as well as the granulomatous pneumonias (Mycobacterium tuberculosis and atypical mycobacteria, Histoplasma capsulatum and Coccidioides immitis). The combined clinical classification, now the most commonly used classification scheme, attempts to identify a person's risk factors when he or she first comes to medical attention. The advantage of this classification scheme over previous systems is that it can help guide the selection of appropriate initial treatments even before the microbiologic cause of the pneumonia is known.

There are two broad categories of pneumonia in this scheme: community-acquired pneumonia and hospital-acquired pneumonia. A recently introduced type of healthcare-associated pneumonia (in patients living outside the hospital who have recently been in close contact with the health care system) lies between these two categories.

A}Community acquired pneumonia (CAP) Is infectious pneumonia in a person who has not recently been hospitalized. CAP is the most common type of pneumonia. The most common causes of CAP vary depending on a person's age, but they include Streptococcus pneumoniae, viruses, the atypical bacteria, and Haemophilus influenzae. Overall, Streptococcus pneumoniae is the most common cause of community-acquired pneumonia worldwide. Gram-negative bacteria cause CAP in certain at-risk populations. CAP is the fourth most common cause of death in the United Kingdom and the sixth in the United States. The term "walking pneumonia" has been used to describe a type of community-acquired pneumonia of less severity (because the sufferer can continue to "walk" rather than require hospitalization).

B}Hospital-acquired Pneumonia- Also called nosocomial pneumonia, is pneumonia acquired during or after hospitalization for another illness or procedure with onset at least 72 hrs after admission. The causes, microbiology, treatment and prognosis are different from those of community-acquired pneumonia. Up to 5% of patients admitted to a hospital for other causes subsequently develop pneumonia. Hospitalized patients may have many risk factors for pneumonia, including mechanical ventilation, prolonged malnutrition, underlying heart and lung diseases, decreased amounts of stomach acid, and immune disturbances. Hospital-acquired microorganisms may include resistant bacteria such as MRSA, Pseudomonas, Enterobacter, and Serratia. Because individuals with hospital-acquired pneumonia usually have underlying illnesses and are exposed to more dangerous bacteria, it tends to be more deadly than community-acquired pneumonia. Ventilator-associated pneumonia (VAP) is a subset of hospital-acquired pneumonia. VAP is pneumonia which occurs after at least 48 hours of intubation and mechanical ventilation.

C}Other types of pneumonia -Severe acute respiratory syndrome (SARS) SARS is a highly contagious and deadly type of pneumonia which first occurred in 2002 after initial outbreaks in China. SARS is caused by the SARS coronavirus, a previously unknown pathogen. -Bronchiolitis obliterans organizing pneumonia (BOOP)- is caused by inflammation of the small airways of the lungs. It is also known as cryptogenic organizing pneumonitis (COP). -Eosinophilic pneumonia- is invasion of the lung by eosinophils, a particular kind of white blood cell. Eosinophilic pneumonia often occurs in response to infection with a parasite or after exposure to certain types of environmental factors. -Chemical pneumonia- is caused by chemical toxicants such as pesticides, which may enter the body by inhalation or by skin contact. When the toxic substance is an oil, the pneumonia may be called lipoid pneumonia. -Aspiration pneumonia- is caused by aspirating foreign objects which are usually oral or gastric contents, either while eating, or after reflux or vomiting which results in bronchopneumonia. The resulting lung inflammation is not an infection but can contribute to one, since the material aspirated may contain anaerobic bacteria or other unusual causes of pneumonia. Aspiration is a leading cause of death among hospital and nursing home patients, since they often cannot adequately protect their airways and may have otherwise impaired defense.

AETIOLOGICAL CLASSIFICATION-

1)VIRAL-is commonly caused by viruses such as influenza virus, respiratory syncytial virus (RSV), adenovirus, and metapneumovirus. Herpes simplex virus is a rare cause of pneumonia except in newborns. People with weakened immune systems are also at risk of pneumonia caused by cytomegalovirus (CMV).

2)BACTERIAL-in first 2 months most common agents are Kleibsiella,Ecoli,& Staphylococci.Betwen 3 months to 3 yrs common agents are S.pneumoniae,H.influenza,& staphylococci.After 3yrs of age S.pneumoniae,& staphylococci.Gram negative bacteria causes pneumunia in early infancy,severe malnutrition,& immunocompromised children.

3)FUNGAL-Fungal pneumonia is uncommon, but it may occur in individuals with immune system problems due to AIDS, immunosuppresive drugs, or other medical problems. The pathophysiology of pneumonia caused by fungi is similar to that of bacterial pneumonia. Fungal pneumonia is most often caused by Histoplasma capsulatum, blastomyces, Cryptococcus neoformans, Pneumocystis jiroveci, and Coccidioides immitis. Histoplasmosis is most common in the Mississippi River basin.

SIGNS & SYMPTOMS- RISK FACTORS include,low birth weight, Malnutrition,Vitamin-A defiecincy,lcack of breast feeding,passive smoking, large family size,family history of bronchitis,advanced birth order,crowding,young age & air pollution.

CLINICAL FEATURES ; Pneumococcal pneumonia-incubation period is 1-3 days.Onset is abrupt with headache,chills,cough & high grade fever.Pleural pain may me there & may reffer to shoulder or abdomen.Respiration is rapid.In sever cases there may be grunting & chest indrawing,difficulty in feeding & cyanosis.Pecussion note is impaired ,air entry is diminished,crepitations and bronchial breathing may be heard over areas of consolidation.Bronchophony & whispering pectoriloquy may be observed.Meningismus may be present in apical pneumonia. Staphylococcal pneumonia-usually follows upper respiratory infections,pyoderma,or other associated purulent diseases.child may have fever,anorexia,grunting respiration.he/she is listless,irritable.abdomen is usually distended due to septicemia,& ileus.Cyanosis may be present.Progression of the signs & symptoms is very rapid.May be sometimes complicated by disseminated disease(involvement of more than 2 anatomically different sites). Hemophillus pneumonia-onset is gradual with nasopharyngeal infection.there is moderate fever,dyspnea,grunting respiration,retaction of lower inter costal spaces.Presentation may mimic acute bronchiolitis. Steptococcal pneumonia-onset is abrupt fever,chills,dyspnoea,rapid respiration,blood streaked sputum,cough & extreme prostration. Primary atypical pneumonia-Incubation period is 10 to 14 days,initial symptoms are malaise,headache, fever,sore throat,myagia, cough.there may be cervical lymphadenopathy. Pneumonia due to gram negative organisms-onset is gradual,assumes life threatening proportions during its course. DIAGNOSIS; If pneumonia is suspected on the basis of a patient's symptoms and findings from physical examination, further investigations are needed to confirm the diagnosis. Information from a chest X-ray and blood tests are helpful, and sputum cultures in some cases. The chest X-ray is typically used for diagnosis in hospitals and some clinics with X-ray facilities. However, in a community setting (general practice), pneumonia is usually diagnosed based on symptoms and physical examination alone.[citation needed] Diagnosing pneumonia can be difficult in some people, especially those who have other illnesses. Occasionally a chest CT scan or other tests may be needed to distinguish pneumonia from other illnesses.

INVESTIGATIONS An important test for pneumonia in unclear situations is a chest x-ray. Chest x-rays can reveal areas of opacity (seen as white) which represent consolidation. Pneumonia is not always seen on x-rays, either because the disease is only in its initial stages, or because it involves a part of the lung not easily seen by x-ray. In some cases, chest CT (computed tomography) can reveal pneumonia that is not seen on chest x-ray. X-rays can be misleading, because other problems, like lung scarring and congestive heart failure, can mimic pneumonia on x-ray.Chest x-rays are also used to evaluate for complications of pneumonia. A complete blood count may show a high white blood cell count, indicating the presence of an infection or inflammation. In some people with immune system problems, the white blood cell count may appear deceptively normal. Blood tests may be used to evaluate kidney function (important when prescribing certain antibiotics) or to look for low blood sodium. Low blood sodium in pneumonia is thought to be due to extra anti-diuretic hormone produced when the lungs are diseased (SIADH). Specific blood serology tests for other bacteria (Mycoplasma, Legionella and Chlamydophila) and a urine test for Legionella antigen are available. Respiratory secretions can also be tested for the presence of viruses such as influenza, respiratory syncytial virus, and adenovirus. Liver function tests should be carried out to test for damage caused by sepsis. PREVENTION Research shows that there are several ways to prevent pneumonia in newborn infants. Testing pregnant women for Group B Streptococcus and Chlamydia trachomatis, and then giving antibiotic treatment if needed, reduces pneumonia in infants. Suctioning the mouth and throat of infants with meconium-stained amniotic fluid decreases the rate of aspiration pneumonia. Vaccination is important for preventing pneumonia in both children and adults. Vaccinations against Haemophilus influenzae and Streptococcus pneumoniae in the first year of life have greatly reduced the role these bacteria play in causing pneumonia in children. Vaccinating children against Streptococcus pneumoniae has also led to a decreased incidence of these infections in adults because many adults acquire infections from children. Hib vaccine is now widely used around the globe. The childhood pneumococcal vaccine is still as of 2009 predominantly used in high-income countries, though this is changing. In 2009, Rwanda became the first low-income country to introduce pneumococcal conjugate vaccine into their national immunization program.

TREATMENT A)Bacterial Antibiotics are used to treat bacterial pneumonia. The antibiotic choice depends on the nature of the pneumonia, the most common microorganisms causing pneumonia in the local geographic area, and the immune status and underlying health of the individual. Treatment for pneumonia should ideally be based on the causative microorganism and its known antibiotic sensitivity. Antibiotic of choice for pneumonia is Cotrimoxazole and Amoxicillin.

DOMICILLIARY TREATMENT OF PNEUMONIA- @Give cotrimoxazole(trimithiprim+sulphmethoxazole){5-7mg/kg/day +25-35mg/kg/day}in two divided doses for 5 days. OR Amoxacillin(30-40mg/kg/dy)in 2-3 divided dosesfor 3-5 days.. @Advice mother to return immediately if child develops chest indrawing ,is unable to feed,or looks sick. @Follow up after 2 days. -check the child for general danger signs, -Asses the child for cough or difficult breathing. -ask,if the child is breathing slower?Is there less fever?Is the child eating better. @if the answer to above que is yes,complete 5 days of Cotrimoxazole or 3-5 days of amoxicillin. @if condition is same ,refer for second line antibiotics to FRU. @if chest indrawing ,or a general danger sign,refer urgently for treatment of severe or very severe pneumonia. Viral Viral pneumonia caused by influenza A may be treated with rimantadine or amantadine, while viral pneumonia caused by influenza A or B may be treated with oseltamivir or zanamivir. These treatments are beneficial only if they are started within 48 hours of the onset of symptoms. Many strains of H5N1 influenza A, also known as avian influenza or "bird flu," have shown resistance to rimantadine and amantadine. There are no known effective treatments for viral pneumonias caused by the SARS coronavirus, adenovirus, hantavirus, or parainfluenza virus. COMPLICATIONS Sometimes pneumonia can lead to additional complications. Complications are more frequently associated with bacterial pneumonia than with viral pneumonia. The most important complications include: Respiratory and circulatory failure Because pneumonia affects the lungs, often people with pneumonia have difficulty breathing, and it may not be possible for them to breathe well enough to stay alive without support. Non-invasive breathing assistance may be helpful, such as with a bi-level positive airway pressure machine. In other cases, placement of an endotracheal tube (breathing tube) may be necessary, and a ventilator may be used to help the person breathe. Pneumonia can also cause respiratory failure by triggering acute respiratory distress syndrome (ARDS), which results from a combination of infection and inflammatory response. The lungs quickly fill with fluid and become very stiff. This stiffness, combined with severe difficulties extracting oxygen due to the alveolar fluid, create a need for mechanical ventilation. Pleural effusion, empyema, and abscess Occasionally, microorganisms infecting the lung will cause fluid (a pleural effusion) to build up in the space that surrounds the lung (the pleural cavity). If the microorganisms themselves are present in the pleural cavity, the fluid collection is called an empyema.

PROGNOSIS With treatment, most types of bacterial pneumonia can be cleared within two to four weeks.Viral pneumonia may last longer, and mycoplasmal pneumonia may take four to six weeks to resolve completely. The eventual outcome of an episode of pneumonia depends on how ill the person is when he or she is first diagnosed. The death rate (or mortality) also depends on the underlying cause of the pneumonia. Pneumonia caused by Mycoplasma, for instance, is associated with little mortality. However, about half of the people who develop methicillin-resistant Staphylococcus aureus (MRSA) pneumonia while on a ventilator will die.[32] In regions of the world without advanced health care systems, pneumonia is even deadlier. Limited access to clinics and hospitals, limited access to x-rays, limited antibiotic choices, and inability to treat underlying conditions inevitably leads to higher rates of death from pneumonia. For these reasons, the majority of deaths in children under five due to pneumococcal disease occur in developing coutries. Adenovirus can cause severe necrotizing pneumonia in which all or part of a lung has increased translucency radiographically, which is called Swyer-James Syndrome. Severe adenovirus pneumonia also may result in bronchiolitis obliterans, a subacute inflammatory process in which the small airways are replaced by scar tissue, resulting in a reduction in lung volume and lung compliance.