LUNG ABSCESS
INTRODUCTION:
Pulmonary abscesses are composed of thick-walled purulent material formed as a result of lung infection and lead to destruction of lung parenchyma, cavitation and central necrosis. Lung abscesses are much less common in children than in adults.
-A primary lung abscess occurs in a previously healthy patient with no underlying medical disorder.
-A secondary lung abscess occurs in a patient with underlying or predisposing conditions.
Lung abscess is a very rare infectious condition in children and is most commonly encountered as a complication of bacterial pneumonia. The majority of patients with lung abscess show an excellent response to antibiotic therapy and only in a minor group, simple drainage or other surgical interventions are required. Empiric parenteral antitherapy is the gold standard treatment of lung abscess in children.
ETIOLOGY:
Most lung abscesses in pediatric patient are believed to develop secondary to bacterial pneumonia. Other predisposing factors are immunodeficiency and immunosuppression states caused by viral infections. Most commonly lung abscesses are caused by anaerobic micro-organisms and among aerobic micro-organisms most common are Staphylococcus aureus and Gram negative bacilli. Fungal and protozoal can can be seen in immunocompromised patients. Other less common causes are Cystic fibrosis, alpha1 antitrypsin deficiency, anesthesia and dental surgery.
CLINICAL MANIFESTATIONS:
The most common symptoms of pulmonary abscess in the pediatric population include cough, fever, tachypnea, dyspnea, chest pain, vomiting, sputum production, weight loss and hemoptysis.
Physical Examination typically reveals tachypnea, dyspnea, retractions with accessory muscle use, decreased breath sounds and dullness to percussion in the affected area.
DIAGNOSIS:
Diagnosis is most commonly made on chest radiography. Classically the chest radiograph shows a parenchymal inflammation with a cavity containing an air-fluid level.
TREATMENT:
The gold standard therapy is administration of parenteral antibiotics with anaerobic and Staphylococcal coverage.
Although 85 to 90% patients heal without sequele in response to antibiotic therapy.
In 10 to 15% of patients simple drainage or other surgical interventions are mandatory.
A chest CT-Scan can provide better anatomic definition, including location and size.
A chest CT-Scan can provide better anatomic definition, including location and size.
The determination of the etiologic bacteria can be very helpful in guiding antibiotic choice.
PROGNOSIS:
Overall, prognosis for children with primary pulmonary abscesses is excellent. The presence of aerobic organism seem to be a negative prognostic indicator particularly in those with secondary lung abscess. Most children become asymptomatic within 7 to 10 days , although the fever may persist for as long as 3 weeks. Radiologic abnormalities usually resolve in 1 to 3 months but can persist for years.
Overall, prognosis for children with primary pulmonary abscesses is excellent. The presence of aerobic organism seem to be a negative prognostic indicator particularly in those with secondary lung abscess. Most children become asymptomatic within 7 to 10 days , although the fever may persist for as long as 3 weeks. Radiologic abnormalities usually resolve in 1 to 3 months but can persist for years.