Overview
Definition:
Empyema in children refers to the presence of purulent material within the pleural space, typically a complication of pneumonia
It represents a localized collection of pus, differing from simple parapneumonic effusion.
Epidemiology:
While the incidence of empyema has declined with widespread antibiotic use, it remains a significant cause of morbidity in children
Streptococcus pneumoniae is the most common causative pathogen, followed by Staphylococcus aureus and gram-negative bacteria
Incidence varies geographically but is estimated to be around 1-2 per 10,000 children annually, with a peak incidence in preschool and early school-aged children.
Clinical Significance:
Untreated or inadequately treated empyema can lead to significant complications including lung abscess, bronchopleural fistula, pleural thickening, restrictive lung disease, and prolonged hospitalization
Prompt and appropriate management is crucial for favorable outcomes and preventing long-term sequelae, making it a critical topic for pediatric residents preparing for DNB and NEET SS examinations.
Clinical Presentation
Symptoms:
Fever, often high and persistent
Persistent cough, sometimes productive
Tachypnea and increased respiratory effort
Chest pain, which may be pleuritic
Lethargy and malaise
Poor feeding or decreased oral intake
History of recent or concurrent pneumonia is common.
Signs:
Fever on examination
Tachycardia
Tachypnea
Decreased breath sounds over the affected area
Dullness to percussion
Egophony or bronchial breath sounds
Grunting respirations in infants
Reduced chest expansion on the affected side.
Diagnostic Criteria:
Diagnosis is typically made based on clinical suspicion and confirmed by imaging and pleural fluid analysis
The presence of frank pus or Gram stain/culture positive for microorganisms in the pleural fluid is definitive
Imaging showing loculated fluid, thickened pleura, and often evidence of underlying pneumonia are supportive.
Diagnostic Approach
History Taking:
Detailed history of recent respiratory illness, especially pneumonia
Duration and character of fever, cough, and chest pain
Associated symptoms like decreased appetite and activity
Vaccination status (e.g., pneumococcal, influenza)
Prior history of lung disease or immunosuppression.
Physical Examination:
Thorough respiratory examination, including inspection for retractions and asymmetry
Auscultation for breath sounds, crackles, and wheezes
Percussion to assess for dullness
Palpation for tactile fremitus
Assessment of vital signs including respiratory rate, heart rate, and oxygen saturation.
Investigations:
Complete blood count (CBC) with elevated white blood cell count and neutrophilia
C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are elevated
Blood cultures may be positive
Chest X-ray (CXR) may show effusion, consolidation, and sometimes loculation
Ultrasound of the chest can help delineate the effusion and guide thoracentesis
CT scan of the chest provides detailed information about the extent of empyema, loculation, pleural thickening, and underlying lung parenchymal changes
Pleural fluid analysis: pH, glucose, lactate dehydrogenase (LDH), protein, cell count with differential, Gram stain, and bacterial culture
An exudative effusion is typically seen with pH <7.20, glucose <40 mg/dL, and LDH >1000 U/L.
Differential Diagnosis:
Simple parapneumonic effusion (uncomplicated effusion)
Organizing pneumonia
Lung abscess
Pleural metastasis (rare in children)
Chylothorax
Hemothorax.
Management
Initial Management:
Prompt initiation of intravenous broad-spectrum antibiotics covering common pathogens (e.g., vancomycin for MRSA coverage, a third-generation cephalosporin for gram-negative coverage)
Supportive care including oxygen therapy, analgesia, and antipyretics
Fluid and electrolyte balance
Nutritional support.
Medical Management:
Intrapleural instillation of fibrinolytic agents like recombinant tissue plasminogen activator (tPA) or dornase alfa (DNase)
These agents help to break down fibrin septations within loculated empyema, facilitating drainage and potentially avoiding or simplifying surgical intervention
Doses: tPA 1-2 mg in 20 mL saline instilled every 12-24 hours for up to 3 days
DNase 5 mg in 50 mL saline instilled every 12-24 hours for up to 5 days
These are typically administered after initial pleural drainage.
Surgical Management:
Video-assisted thoracoscopic surgery (VATS) is the current gold standard for managing complicated empyema or when medical management fails
VATS allows for pleural space debridement, lysis of adhesions and loculations, decortication if necessary, and placement of chest tubes for drainage
Indications for prompt VATS include failure to improve with antibiotics and intrapleural fibrinolytics, significant loculation or thick fibrin peel, large empyema, or suspicion of bronchopleural fistula
Open thoracotomy is reserved for cases where VATS is not feasible or has failed.
Supportive Care:
Continuous monitoring of vital signs and respiratory status
Chest tube management, including monitoring of drainage output and potential for irrigation
Pain management
Physiotherapy and pulmonary rehabilitation to promote lung expansion and prevent atelectasis
Nutritional assessment and support to ensure adequate caloric intake.
Complications
Early Complications:
Failure of medical management requiring surgery
Hemorrhage from pleural procedures
Air leak from chest tube
Persistent fever
Sepsis.
Late Complications:
Pleural thickening and restriction leading to chronic respiratory dysfunction
Bronchopleural fistula
Lung abscess
Empyema necessitatis (extension through chest wall).
Prevention Strategies:
Prompt and adequate treatment of pneumonia with appropriate antibiotics
Early recognition and management of parapneumonic effusions
Judicious use of intrapleural fibrinolytics to prevent loculation
Timely surgical intervention when indicated.
Prognosis
Factors Affecting Prognosis:
Age of the child
Promptness of diagnosis and treatment
Causative organism
Extent and complexity of empyema (loculation, pleural thickening)
Development of complications
Underlying comorbidities.
Outcomes:
With timely and appropriate management, including antibiotics, drainage (medical or surgical), and supportive care, most children with empyema achieve a good recovery
Complete resolution is expected in the majority of cases
However, some may experience long-term sequelae such as reduced lung function or chronic pleural issues.
Follow Up:
Post-discharge follow-up with a pediatrician or pulmonologist is recommended
This may include serial chest X-rays to monitor for residual pleural thickening or effusion
Pulmonary function tests may be considered for children with persistent symptoms or significant pleural abnormalities
Education for parents on recognizing signs of recurrence or new respiratory infections.
Key Points
Exam Focus:
Understand the differences between simple parapneumonic effusion and empyema
Know the indications for intrapleural fibrinolytics (tPA/DNase) and VATS
Recognize the typical pathogens and antibiotic regimens
Differentiate between medical and surgical management strategies
Be aware of the diagnostic criteria for empyema.
Clinical Pearls:
Always consider empyema in a child with persistent fever and cough after pneumonia
Ultrasound is excellent for differentiating simple from complex effusions and guiding aspirations
Loculated effusions are a strong indication for intrapleural fibrinolytics or VATS
Early surgical intervention (VATS) often leads to faster recovery and fewer complications than delayed management.
Common Mistakes:
Delaying antibiotics or drainage
Misinterpreting imaging findings
Over-reliance on antibiotics alone for loculated empyema
Inadequate chest tube management
Not considering VATS in cases unresponsive to medical therapy.