Imaging in immunocompetent children who have pneumonia

Radiographic findings of adenoviral pneumonia in children

OBJECTIVE

Adenovirus pneumonia is a common cause of community-acquired pneumonia in children and can mimic bacterial pneumonia, but there are few publications on its radiographic features. This study has evaluated the chest radiography findings of community-acquired adenovirus pneumonia in children. The frequency of radiological findings mimicking bacterial pneumonia was investigated. The clinical features of patients with adenovirus pneumonia possessing radiological findings mimicking bacterial pneumonia were also evaluated.

MATERIALS AND METHODS

The chest radiographs of patients diagnosed with adenovirus pneumonia were retrospectively reviewed. The chest radiographs were interpreted independently by a pediatric infectious disease specialist and a pediatric radiologist. Chest radiography findings mimicking bacterial pneumonia (bacterial-like) were specified as consolidation +/- pleural effusion. Other findings on chest radiography or a completely normal chest X-ray were specified as findings that were compatible with "typical viral pneumonia".

RESULTS

A total of 1407 patients were positive for adenovirus with respiratory multiplex PCR. The 219 patients who met the study criteria were included in the study. Chest radiographs were normal in 58 (26.5 %) patients. The chest radiograph findings mimicked bacterial pneumonia in 41 (18.7 %) patients.

CONCLUSION

Adenovirus pneumonia occurs predominantly in children aged five years and younger, as with other viral pneumonias. The radiographic findings in adenovirus pneumonia are predominantly those seen in viral pneumonia. Increasing age and positivity for only adenovirus without other viruses on respiratory multiplex PCR were associated with the chest radiograph being more likely to be "bacterial-like". Adenovirus may lead to lobar/segmental consolidation at a rate that is not very rare.

Pediatric Lower Respiratory Tract Infections: Imaging Guidelines and Recommendations

Lower respiratory tract infection (LRTI) remains a major cause of morbidity and mortality in children. Various organisms cause LRTI, including viruses, bacteria, fungi, and parasites, among others. Infections caused by 2 or more organisms also occur, sometimes enhancing the severity of the infection. Medical imaging helps confirm a diagnosis but also plays a role in the evaluation of acute and chronic sequelae. Medical imaging tests help evaluate underlying pathology in pediatric patients with recurrent or long-standing symptoms as well as the immunocompromised.

Lung ultrasound in pediatric radiology - cons

In the 1990s, intensivists suggested a new type of sonography: lung ultrasound, based on artefacts that receive information even from physical acoustic phenomena not directly convertible into images of the human body. They compared the artefacts from the lung zones with no acoustic window with various computed tomography (CT) patterns. They used and still use US as a tool to evaluate patients bedside, i.e. monitoring of lung recruitment. They included Lung ultrasound in what was termed POCUS (Point-of-Care Ultrasound). Lung ultrasound has been progressively extended to paediatrics in general. The most appealing novelty has been the diagnosis of pneumothorax. Lung ultrasound was developed as a support tool for critical patients. Extrapolation with mass diffusion, in the absence of appropriate training, has led to misunderstandings and dangerous therapeutic diagnostic drifts.

The radiological diagnosis of pneumonia in children

Despite the importance of paediatric pneumonia as a cause of short and long-term morbidity and mortality worldwide, a reliable gold standard for its diagnosis remains elusive. The utility of clinical, microbiological and radiological diagnostic approaches varies widely within and between populations and is heavily dependent on the expertise and resources available in various settings. Here we review the role of radiology in the diagnosis of paediatric pneumonia. Chest radiographs (CXRs) are the most widely employed test, however, they are not indicated in ambulatory settings, cannot distinguish between viral and bacterial infections and have a limited role in the ongoing management of disease. A standardised definition of alveolar pneumonia on a CXR exists for epidemiological studies targeting bacterial pneumonias but it should not be extrapolated to clinical settings. Radiography, computed tomography and to a lesser extent ultrasonography and magnetic resonance imaging play an important role in complicated pneumonias but there are limitations that preclude their use as routine diagnostic tools. Large population-based studies are needed in different populations to address many of the knowledge gaps in the radiological diagnosis of pneumonia in children, however, the feasibility of such studies is an important barrier.

Chest ultrasound in children: critical appraisal

We analyze the potential use of ultrasound in the study of the thorax in children. The physical limitations imposed on sonography by the ventilated lung and thoracic cage are well known. We want to discuss new US applications based on the clinical and methodological experience gained in adults as outlined by emergency and critical care specialists. These specialists take information from physical acoustic phenomena that is not directly convertible into images of the human body, starting with the interpretation and handling of artifacts. We give a critical assessment from a radiologic viewpoint that is both necessary and important.

Radiological findings in 210 paediatric patients with viral pneumonia: a retrospective case study

OBJECTIVE

The objective of this study was to assess the radiological presentations of different types of viral pneumonia in children.

METHODS

Nasopharyngeal swab specimens and bronchial aspirate samples from children with acute respiratory infections were obtained and tested for influenza B, adenovirus, respiratory syncytial virus and parainfluenza (Types 1, 2 and 3) by direct immunofluorescence assay, or for influenza A (Subtype H1N1) by quantitative real-time polymerase chain reaction. The chest radiographs of the 210 confirmed cases of viral pneumonia were analysed retrospectively by two independent radiologists for the identification, characterisation and description of the distribution of imaging abnormalities. The cases were divided into six groups on the basis of confirmed causative viral agent, and radiographic findings were compared, analysed and presented.

RESULTS

The abnormal chest radiograph findings consisted of bilateral patchy areas of consolidation (n=133), interstitial lung disease (n=33), diffuse areas of air space consolidation (n=29) and lobar consolidation (n=15). The abnormalities were distributed bilaterally in 195 cases and observed more frequently in the lower zones than in other regions. The radiological findings varied significantly among the six groups (p=0.0050). Pairwise comparison showed significant difference between influenza A (H1N1) and adenovirus (p=0.0031) only.

CONCLUSION

The predominant radiological finding in paediatric viral pneumonia was bilateral patchy areas of consolidation. The radiological findings differed significantly only between adenovirus and influenza A pneumonia. The diagnosis of the specific causative organism requires laboratory confirmation.

Radiology in paediatric non-traumatic thoracic emergencies

Non-traumatic thoracic emergencies in children are very frequent, and they usually present with breathing difficulties. Associated symptoms may be feeding or swallowing problems or less specific general symptoms such as fever, sepsis or chest pain. The emergencies always require a rapid diagnosis to establish a medical or surgical intervention plan, and radiological imaging often plays a key role. Correct interpretation of the radiological findings is of great importance in diagnosing and monitoring the illness and in avoiding serious complications. Plain radiography with fluoroscopy still remains the most important and frequently used tool to gain information on acute pulmonary problems. Ultrasound is the first choice for the detection and treatment of simple and complicated pleural effusions. Cross-sectional techniques such as multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) are mainly used to study pulmonary/mediastinal masses and congenital abnormalities of the great vessels and the lungs. This article will discuss the choice of imaging technique, the urgency of radiological management and the imaging characteristics of acquired and congenital causes of non-traumatic thoracic emergencies. They represent common conditions involving the respiratory tract, chest wall and the oesophagus, as well as the less frequent causes such as tumours and manifestations of congenital malformations.

Imaging of Chest Infections in Children

■ Imaging studies have limited value in the differentiation between viral and bacterial lower respiratory tract infections (moderate evidence).

■ CT provides more information than plain radiographs for complicated pulmonary infections with empyema, pleural effusion, or bronchopleural fistula (moderate evidence).

■ In immunocompromised patients, CT has been shown to characterize the type of infection better than plain radiographs (moderate evidence).

■ Ultrasound has an advantage over CT in the identification and characterization of complicated effusions (moderate evidence).

■ Early detection and therefore intervention for pleural complications of pneumonia are critical and can result in better outcomes (moderate evidence).

■ Early surgery (VATS) is more cost-effective than thoracotomy (without or with image guidance) in the treatment of empyemas in children (strong evidence).

Imaging of round pneumonia and mimics in children

Various diseases in the pediatric age group can present as an intrathoracic rounded opacity on a chest radiograph. The purpose of this pictorial essay is to emphasize the imaging appearance of round pneumonia, an entity that occurs especially in the pediatric population. Additional pathologies with similar chest radiographic appearances are also presented. The diagnosis of round pneumonia should be made in children who have the typical clinical presentation along with chest radiographs demonstrating the characteristic findings.

Antibiotics in childhood pneumonia

Pneumonia is one of the most common global childhood illnesses. The diagnosis relies on a combination of clinical judgement and radiological and laboratory investigations. Streptococcus pneumoniae remains the most important cause of childhood community-acquired pneumonia. In addition, viruses (including respiratory syncytial virus) and atypical bacteria (Mycoplasma and Chlamydia) are likely pathogens in younger and older children in developed countries. In the minority of cases only, the actual organism is isolated to guide treatment. Antibiotics effective against the expected bacterial pathogens should be instituted where necessary. The route and duration of antibiotic therapy, the role of emerging pathogens and the impact of pneumococcal resistance and conjugate pneumococcal vaccines are also discussed.