Pneumonia adquirida na comunidade em crianças: etiologia, patogênese e tratamento ambulatorial

Abstract

Introduction: Pneumonia is the involvement of the lung parenchyma, with fever, cough and/or shortness of breath, evidenced by history and physical examination or by infiltrates on chest x-ray. In children, the term for lower respiratory tract infection may include bronchitis, bronchiolitis, and pneumonia. The latter is an important cause of morbidity in rich countries and of morbidity and mortality in countries with few resources. The annual incidence of pneumonia in children <5 years of age was 231/1000 in 2015, with 80% progressing to severe disease and requiring hospitalization and case fatality rates of 0.3 to 15% in poorer countries. Therefore, it is a relevant topic for public health at an international level.Objective: to discuss the pathogenesis, etiology and outpatient treatment of pneumonia in children.

Methodology: Literature review of the Scielo, PubMed and VHL databases, from January to March 2024, with descriptors “pneumonie”, “children”, “pathogenesis”, “etiology” and “treatment”. Articles from 2019 to 2024 (80 studies) were included. Studies with other criteria were excluded, with 05 full articles. Results and Discussion: Pneumonia is more common in children under five years of age and in colder months. Its risk factors are: environmental crowding, school-age siblings and comorbidities (asthma, congenital heart disease, cystic fibrosis, immunodeficiencies). Cigarette and alcohol use can lead to aspiration in adolescents, compromising coughing and epiglottic reflexes. Children introduce viral agents into homes, resulting in secondary infections in parents and siblings. The most common agents in community-acquired pneumonia (CAP) are viruses and bacteria (Streptococcus pneumoniae, Staphylococcus aureus and Streptococcus pyogenes); in children > 5 years old, we have atypical microorganisms: Mycoplasma pneumoniae and Chlamydia pneumoniae. If in-hospital pneumonia, gram-negative bacilli must be considered. Pathogens are transmitted by droplets from the index case, fomites, and initial colonization of the nasopharynx followed by aspiration or inhalation. The involvement can be lobar or bronchopneumonia when bacterial and interstitial if viral. Children with CAP who are treated in an outpatient setting are treated empirically. It is not necessary to obtain laboratory or radiographic data in an attempt to suggest a bacterial etiology in children who are well enough to be treated as outpatients. Decisions regarding empirical antimicrobial therapy for CAP in children are generally based on age unless there are other predominant epidemiologic or clinical factors to suggest a specific etiologic agent. In infants and children four months and older with uncomplicated pneumonia, the usual duration of antimicrobial therapy is seven days for agents other than azithromycin; for children with mild illness and adequate follow-up, five days may be sufficient, as long as the child is afebrile for 24 hours and shows clinical improvement. Conclusion: Pneumonia can have different etiologies depending on the age of the child and the environment in which it is acquired. This directly influences therapeutic management. The decision to hospitalize a child with pneumonia must be individualized and is based on age, underlying medical problems, and severity of illness.