In by Raphikammer

What is pneumonia?

A pneumonia ( pneumonia)  is an acute or chronic inflammation of the alveoli (alveolar pneumonia) and / or of the lung tissue (interstitial pneumonia). This leads to a swelling and increased blood flow to the affected lung area. Typically, the disease is associated with fluid accumulation in the lung tissue.

Alveolar pneumonia is subdivided into lobar or focal pneumonia, depending on extent. In the lobar pneumonia an entire lobe of the lung or an entire lung segment is mostly affected. Herd pneumonias are so named because one or more sites of inflammation have developed within a lung lobe. Pneumonia can also originate from the bronchi and attack the surrounding tissue (bronchopneumonia).

Pneumonia causes around 400,000 people a year in Germany. In times of heavy flu, ie especially in winter, the number is still significantly higher. The risk group includes, in particular, infants and toddlers as well as elderly patients over the age of 60 and people with severe chronic illnesses. They are particularly susceptible to the development of pneumonia due to their not yet fully developed or weakened immune system .

The triggers of pneumonia are mostly bacteria, more rarely viruses or fungi. The disease can develop very differently depending on the general health of the patient and the type of the pathogen. About one in seven pneumonia is so severe that it requires hospitalization. Pneumonia is the most common fatal infection in Western Europe. It ranks number 5 in the nationwide cause of death statistics, with approximately 3 to 5% of patients dying annually. Particularly dangerous are the diseases that are acquired in the hospital, the so-called nosocomial pneumonia. They are usually difficult to treat because their agents prove to many antibiotics as resistant (resistant).

Transmission paths

The causative agents of pneumonia usually originate either from the nasopharynx or are transmitted by droplet infection from other patients by speaking, coughing or sneezing.

Normally, the lung has various defense mechanisms to prevent the ingress of bacteria, viruses or other pathogens. Small cilia, which sit in the mucous membrane of the respiratory tract and move constantly, prevent, for example, dust particles in the lower respiratory tract as far as the alveoli and can accumulate there. If, with the inhaled air, particles once reach the alveoli, they are usually transported away by cells of the immune system and rendered harmless. If the defense mechanisms of the lung are disturbed, however, microorganisms can be deposited and cause inflammation. This so-called airborne infection path is by far the most common.

However, pneumonia can also be triggered by corrosive and toxic gases, various medications or radiotherapy. Likewise, foreign bodies that accidentally enter the respiratory tract can lead to the development of pneumonia (aspiration pneumonia). In rare cases, pneumonia is caused by pathogens transmitted by the bloodstream (haematogenous infection) and washed into the lungs.

Spectrum of pathogens

While in adults, pneumococcal infection may cause pneumonia, the bacterium Haemophilus influenzae type b (Hib) is the most common pathogen in infants. In infants, however, Staphylococcus aureus is the main pathogen for pneumonia. Mycoplasma , Legionella and Chlamydia pneumoniae also play a role in adults . But it can also cause viruses, fungi or parasites inflammation of the lungs.

The pathogen spectrum of nosocomial pneumonia (hospital-acquired pneumonia) differs significantly from the so-called community-acquired diseases. The cause of these inflammations are mainly enterobacteria such as Pseudomonas aeruginosa, Klebsiella and Staphylococcus. Many patients have less resistance and therefore insufficient protection against pathogens. The germs in the hospital itself are another problem because they often become insensitive ( resistant ) to the commonly prescribed antibiotics and therefore are difficult to treat in many cases.

Secondary pneumonia

In the case of various underlying diseases, there is a risk that pneumonia will develop in addition. Due to the underlying disease, the lung is already damaged, so that the development of pneumonia is favored. This is called secondary pneumonia. Hypostatic pneumonia is the most common of all secondary pneumonia caused by poor ventilation and circulation in the lower lung fields, for example in bedridden patients. This creates ideal conditions that bacteria can colonize and cause inflammation.

Even with existing heart disease (such as left heart failure or after a heart attack) may develop pneumonia. Due to the damaged heart, there is a backwater in the lungs, so that a so-called congestive pneumonia can develop.

General risk groups

People whose immune system is not fully developed or already weakened are primarily affected by pneumonia . These include mainly infants and toddlers and the elderly over 60 years, but also patients with chronic heart disease, chronic bronchitis, diabetes (diabetes) or severe neurological diseases. The general risk group also includes those infected with HIV, alcoholics, persons receiving chemotherapy or radiotherapy, and patients requiring artificial respiration. In this case, especially for the purification of the lungs, the lack of coughing fitsan important role. Due to the weakening of the immune system, the range of other people with pathogens (eg fungi or so-called other mycobacteria), which normally would not cause pneumonia in healthy people, is widening in this group of people .

In addition to these general risk factors, quite different factors often play a role in the development of pneumonia, depending on the type of agent. For example, pneumonia often occurs as a complication of other diseases such as influenza (influenza) or measles.

Classic bacterial pneumonia

The typical pneumococcal pneumonia usually occurs during the cold season and is primarily observed in elderly or pre-existing individuals. Often the disease is preceded by an infection in the throat or throat area. Often the classic pneumonia then begins with chills and fever over 38.5 ° C, which can often rise up to 40 ° C. The patients usually make a very sick impression. As a rule, coughing also sets in after a short time . Initially, it is still dry, but after a while, mucus is coughed up, which is green, yellow, brown or rusty.

Striking is a mostly superficial, strained and fast breathing (tachypnea) in those affected. Depending on the affected lung side, the respiratory movement is clearly limited. Often, patients complain of chest pain, especially inhalation, caused by concomitant pneumonia. In some patients there is still a shortness of breath, which is due to the so-called nostrils expresses. The Nasenflügeln is especially in small children a sure indication that they suffer from respiratory distress. Due to the superficial and fast breathing, the oxygen supply is no longer optimally guaranteed. Occasionally one can see the resulting lack of oxygen on the lips, nose, toenails or fingernails, which then appear bluish to violet (cyanosis). However, the infection can also be very atypical with slow deterioration of the general condition.

Atypical pneumonia

The atypical pneumonia is for the most part caused by viruses and / or so-called mycoplasmas caused. In contrast to pneumococcal pneumonia, the symptoms develop much more slowly, so that the formation of the full clinical picture usually takes several days. Patients are generally younger and healthier than classic pneumonia. In atypical pneumonia, headache and pain in the limb are in the foreground, whereby the general condition is usually little impaired. Chills rarely occur, the fever curve is slightly increasing and barely reaches values ​​above 38.5 ° C. Those affected suffer less often from respiratory distress than is the case with classical bacterial pneumonia. Furthermore, very few patients complain of respiratory pain. The cough is dry and long-lasting, a so-called unproductive cough, ie no mucus is coughed up. In children, an eardrum inflammation is often observed.

Special forms:

Legionella pneumonia ( legionnaires’ disease )
Legionella can be transmitted through air conditioners, showers or baths. This is especially the case if the water can not be heated above 60 ° C. At risk are mainly the elderly, patients with diabetes (diabetes) or a weakened immune system . Less than 10% of those infected develop pneumonia with a high fever, respiratory-related chest pain, and bleeding in the sputum .

Chlamydia pneumonia
The signs of chlamydia pneumonia correspond to atypical pneumonia. In this form of pneumonia is a persistent, mostly dry cough in the foreground. Frequently, patients also complain of fever and muscle aches. If the disease is not treated properly or not at all, it is often very tedious (up to 3 months). The pathogens of the so-called ornithoses or psittacoses belong to the chlamydia. If there are parrots or other species of birds in the patient’s house, parrot disease (psittacosis) should always be considered.

Special features in childhood

Children with pneumonia usually appear very dull, look pale and sick. Often they sweat a lot. As in adulthood , typical symptoms such as coughing , chills, rapid heart rate, strained and rapid breathing (tachypnea), shortness of breath (dyspnea) and the associated nasal blowing often occur on. The latter is especially in infants and toddlers a clear sign of severe pneumonia. The cough is often dry, distressing and painful at first. After a few days, greenish mucus usually forms, coughing up older children, while infants may ingest and vomit. In children, there are also frequent skin retractions of the chest, abdominal pain, nausea and earache (middle ear, eardrum inflammation). Small children have a high fever especially in bacterial pneumonia, while in pneumonia caused by viruses and mycoplasma, the fever curve barely exceeds values ​​above 38.5 ° C.

In children, however, pneumonia can also be completely uncharacteristic, especially in infants, the general condition can hardly be affected with only slightly elevated temperature. Sick infants and toddlers are usually hospitalized.

Often, pneumonia is the result of a common cold, eg bronchitis , but it also occurs as a complication of measles or cystic fibrosis . In infants and young children, the bacteria Staphylococcus aureus, Haemophilus influenzae type b (Hib) and pneumococci are among the most common pathogens. In the first year of life, children with a four-time vaccination who are still immunized against other diseases should be protected against Haemophilus influenzae type b (Hib). Children can be vaccinated against pneumococci from the 2nd month of age.


Complications of pneumonia can occur in the lungs as well as in other organs. One of the most serious complications is the so-called respiratory failure. The patient is no longer able to breathe independently and to absorb enough oxygen. A severe oxygen deficiency is the result. A blood infection (sepsis) is also one of the worst complications. The pathogens are scattered throughout the body, causing inflammation in many organs. Both complications necessarily require intensive care treatment with possibly mechanical ventilation.

Any acute pneumonia can develop into chronic inflammation with a protracted course. Such chronic pneumonia can lead to sloughing of the bronchi (bronchiectasis), which can cause recurrent inflammation or even hemorrhages of the lungs. As a result of the inflammatory reactions, the lung tissue is scarred, which is then less distensible.

Since patients with severe pneumonia are bedridden for a long time, thromboses (closure of a vein by a blood clot) may form. In the worst case, such a thrombus can be trafficked into the bloodstream and occlude a vessel in the lungs (embolism).

As a result of pneumonia it can also lead to meningitis (meningitis) or to a collection of pus in the brain (brain abscess). In addition, inflammatory changes to the heart, joints and bones are to be feared.

Research Methods

Anamnesis and examination

At the beginning of each examination, the attending pulmonary specialist will ask you in detail about the current complaints, but also about previous and already existing illnesses. This so-called anamnesis is thus a first and very important guide to be able to recognize and assess possible pneumonia . In the subsequent physical examination, the physician attempts to detect possible densities of the lung tissue that occur in any form of pneumonia. Listening to the lungs and heart is done with a stethoscope(Auscultation) and the knocking (percussion) of the patient in the foreground. The so-called voice fremitus gives the doctor further important diagnostic information. In this exam, the patient says “99” so that the physician can feel transmitted vibrations on his back. If the lung tissue is compressed, as is the case with pneumonia, the vibration is amplified. An additional possibility to detect compressed lung tissue is bronchophony. The doctor whispers to the patient “66” and at the same time stops the lungs. The speech is transmitted much worse in compressed tissue.


Further important information is provided by bacterial investigations. On the one hand, there is the possibility of investigating the coughing, the so-called sputum, microscopically on various pathogens. On the other hand, one can culture bacteria from a blood sample of the patient (creating a bacterial culture), so as to get information about the possible cause of pneumonia.

Both methods have their drawbacks: the microscopic examination is a very fast variant for pathogen detection. However, there is always the danger of contamination, so it is not very reliable. In a bacterial culture, however, the pathogen can be identified and tested at the same time, even if so-called resistance forces ( resistances) exist against various antibiotics. But unfortunately, the cultivation takes quite a long time (2-3 days), so that in many cases, even before a precise knowledge of the pathogen with a therapy must begin.

blood count

On the basis of the blood picture can also draw first conclusions about the actual presence of pneumonia and their nature. Thus, in a bacterial pneumonia, the proportion of white blood cells ( leukocytes ) is usually increased, while in viral pneumonia no significant increase in the number of leukocytes is conspicuous. In bacterial pneumonia also found immature precursors in the blood, what the physicians call a left shift. In atypical pneumonia , on the other hand, there may be an increase in lymphocytes (special white blood cells, which occur alongside the blood in the lymph and bone marrow).


Patients who are suspected of having pneumonia or who have already developed significant disease symptoms will have their lungs x-rayed. On the basis of the X-ray, conclusions can be drawn on the place of origin and the possible causes of pneumonia. Although there are very specific and specific findings for certain causes or pathogens, they can occasionally also appear quite untypically. Foci of inflammation can be detected in the X-ray image as so-called shadows or densifications, which are visible as brightening. The X-ray image may also provide clues to possible underlying diseases that may have favored pneumonia.

Antigen or antibody detection

This method is mainly used in cases of suspected atypical pneumonia. Urine, sputum (sputum) and / or lung tissue or rinse water taken by bronchoscopy are examined.

differential diagnosis

In the case of delayed-healing pneumonia, a differential diagnosis must be made of lung cancer, an inhaled foreign body (eg peanut) or tuberculosis. If antibiotic therapy does not improve the symptoms, allergic inflammation should be strictly excluded.


The treatment of pneumonia depends on its cause or the type of the pathogen and the resulting complaints. It includes both general and medicinal measures.

General measures

In any case, patients should be sparing with pneumonia, in case of fever the treating pulmonologist will recommend bed rest. In particularly difficult cases even a hospitalization is required. This affects primarily elderly and immunocompromised persons as well as infants. Because with them quickly sets in a shortness of breath with oxygen deficiency, which makes an additional oxygen or in the worst case, even a necessary ventilation.

Patients with pneumonia should drink a lot. This is especially important when taking agents for mucus solution.

By means of breathing exercises and a regular tapping massage (tapping the ribcage), the symptoms of pneumonia can also be alleviated.

Medical therapy

In most cases you have to start with a drug treatment with pneumonia before the exact pathogen is known. Therefore, so-called broad-spectrum antibiotics are prescribed. These are medicines that are effective against many of the possible germs. As soon as the pathogen is known, the previously used antibiotic may be exchanged for a more targeted one.

The classic pneumonia pneumococcal is usually treated with penicillin. Haemophilus influenzae type b (Hib), a common pathogen in childhood, can be successfully controlled by ampicillin or amoxicillin. Pneumonia caused by chlamydia, mycoplasmaor legionella can be well treated with so-called macrolides.

Treatment with antibiotics is limited to pneumonia caused by bacteria. Virus-induced pneumonia can not actually be influenced by medication, so people are limited to general measures and try to avoid complications. Often, however, a so-called bacterial superinfection develops here (additional infection with bacteria), which in turn requires the administration of antibiotics.

Patients suffer from a productive cough(ie they make a lot of tough mucus, which is difficult to cough up), they get prescribed so-called secretolytic drugs. These are medicines that dissolve and liquefy the mucus in the lungs so that they can be coughed off better. On the other hand, if the cough is dry, as is usually the case with atypical pneumonia, so-called antitussives can suppress the onset of cough. It is important to know that secretolytics and antitussives must never be used in combination, as otherwise the dissolved mucus can not be coughed off and an already existing respiratory distress would worsen.


The prognosis of pneumonia depends on several factors. For example, which pathogen is the causative agent, how it is about the defenses of the patient and whether the right therapy was chosen, is of crucial importance. People of higher age or with pre-existing illnesses such as the heart or lungs have a less favorable prognosis than young or healthy patients.

Pneumonia in patients without risk factors can be treated on an outpatient basis, they have a favorable prognosis. Mortality is below 2%. If inpatient therapy becomes necessary, the mortality rate is 2 to 10%. The data are subject to rather large fluctuations, since hospital admissions are often associated with severe pre-existing or advanced age, which in itself have an increased mortality result. Interestingly, the mortality rate for inpatient pneumococcal pneumonia is particularly high and is still 20% today. In severe forms of pneumonia, which must always be treated in the hospital, about 20 to 50% of all patients die.

The so-called nosocomial pneumonia acquired in the hospital generally has a much worse prognosis than the community-acquired infections because of the persistent pathogens. Many of the disease-causing germs have developed so-called resistance over time , so that the therapy with certain antibiotics is no longer able to counteract them. The drug used can then in many cases not destroy the pathogen and / or prevent its further spread in the body. The cause of such resistance is the increased use of antibiotics in hospitals. Two-thirds of hospital-acquired infections that are fatal are pneumonia.

All in all, it is estimated that around 40,000 to 50,000 deaths a year are caused by severe pneumonia in Germany . In heavy flu times the number of pneumonia increases. As a result of flu ( influenza ) it can come, especially in immunosuppressed patients to develop pneumonia.


Vaccination against pneumococci

A vaccination against pneumococci , the most common cause of bacterial pneumonia in old age, is recommended by the Standing Vaccination Commission (STIKO) at the Robert Koch Institute for anyone over the age of 60 years. The one-time vaccination should be with a polysaccharide vaccine containing 23 antigens of different types of pneumococci responsible for 90% of the disease.

The vaccination against pneumococci is also recommended by the STIKO for all children from the 2nd month of age. The four anti-pneumococcal vaccinations are usually given in parallel with the combination dose of diphtheria, tetanus, whooping cough, polio, hepatitis B and Haemophilus influenzae type b (Hib), ie at 11 to 14 months the infant should ideally be primed with pneumococci. For this primary immunization, a conjugate vaccine is available that is tailored to the immature infant and toddler immune system and protects against 13 or 10 of the most dangerous and common types of pneumococci.

For children, adolescents and adults at increased risk to health (eg congenital or acquired immunodeficiencies or immunosuppression including absent or incapacitated spleen (asplenia), chronic diseases such as asthma or diabetes, kidney or heart disease, bone marrow transplantation, and before (or at the latest after) use of a cochlear implant) a pneumococcal vaccine is also recommended to protect these high-risk patients from pneumococcal diseases such as pneumonia or meningitis.

The vaccine protection starts about three weeks after the vaccination. Persons with a continuing health risk can receive the polysaccharide vaccine from the age of five. For the vaccine previously vaccinated with conjugate vaccine, as recommended, the minimum interval for polysaccharide vaccine vaccination should be 2 months. In adults, a single injection is usually sufficient. In certain risk groups, such as people with immunodeficiencies or chronic kidney disease, it may be useful to refresh the pneumococcal vaccine every 6 years. About the need for a repeat vaccination, depending on the age and the underlying disease, decides the attending physician or the treating physician.

The costs for the pneumococcal vaccine according to the STIKO recommendation are taken over by the health insurances of the health insurances.

Vaccination against influenza viruses

You can protect yourself against the influenza virus ( influenza virus), which usually causes illnesses in the cold season, through an annual vaccination. As a result of flu (influenza) it can come, especially in immunosuppressed patients to develop pneumonia. 80% of these pneumonias are caused by an additional bacterial infection, eg with pneumococci.

General precautionary tips

In general, the respiratory tract can be protected by the following measures:

  • Do not smoke
  • Optimize room climate
  • Vitamin C intake (vegetables, fruits)
  • Sufficient movement in the fresh air