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Types of pneumonia
Last reviewed: 04.07.2025
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All pneumonias are divided into two large groups according to the conditions of infection: community-acquired (home-acquired) and hospital-acquired (hospital, nosocomial). Hospital-acquired pneumonias are those that develop after 72 hours of hospital stay or within 72 hours after discharge from it. Pneumonias in patients with immunodeficiency are considered separately.
Among hospital pneumonias, it is customary to distinguish ventilator-associated pneumonia (VAP), i.e. pneumonia that occurs in children on artificial ventilation (AVL), and ventilator-non-associated, or simply hospital pneumonia. Ventilator-associated pneumonias, in turn, are usually divided into early (occurring in the first 3 days of AVL) and late (occurring in a child on AVL for more than 3 days).
This division is due to differences in the mechanisms of development of these diseases, in morphological and clinical signs, in the types of infecting microorganisms.
According to etiology, pneumonia is divided (indicating the pathogen) into viral, bacterial, fungal, parasitic, and mixed.
According to pathogenesis, pneumonia is divided into primary, which develops in children without significant premorbid disorders of the body's anti-infective defense, and secondary, which develops in children with significant premorbid disorders of the leading links of the body's anti-infective defense. In such a case, pneumonia is indicated in the diagnosis as a manifestation or complication of other serious diseases.
Based on clinical and radiological data, the following are distinguished: focal, focal-confluent, lobar (croupous), segmental and interstitial pneumonia.
According to the course, acute and protracted pneumonia are distinguished. With full treatment, uncomplicated pneumonia regresses in 2-4 weeks, complicated - in 1-2 months. Protracted course is diagnosed in the absence of reverse dynamics in a period of 1.5 to 6 months.
Depending on the severity of the disease, there are mild and severe pneumonias that require intensive care, as well as complicated ones.
Pneumonia may occur with pulmonary and extrapulmonary complications. Pulmonary complications: pleurisy, intrapulmonary destruction (bullae, abscesses), pneumothorax, pyopneumothorax, pleural empyema. Extrapulmonary complications: infectious toxic shock, disseminated intravascular coagulation syndrome (DIC syndrome), acute renal failure.