A Community-acquired Lung Abscess Attributable to Streptococcus pneumoniae which Extended Directly into the Chest Wall

Logistic regression analysis of clinical and computed tomography features of pulmonary abscesses and risk factors for pulmonary abscess-related empyema

OBJECTIVES

This study was conducted to investigate the risk factors for pulmonary abscess-related empyema by investigating the clinical characteristics and chest computed tomography imaging features of patients with pulmonary abscesses.

METHODS

We retrospectively analyzed the chest computed tomography findings and clinical features of 101 cases of pulmonary abscess, including 25 cases with empyema (the experimental group) and 76 cases with no empyema (the control group). The potential risk factors for pulmonary abscess-related empyema were compared between the groups by using univariate and multivariate logistic regression analyses.

RESULTS

The incidence of pulmonary abscess-related empyema was 24.8% (25/101). Univariate analysis showed that male gender, diabetes, pleuritic symptoms, white blood cells >10×109/L, albumin level <25 g/L, and positive sputum cultures were potential clinical-related risk factors and that an abscess >5 cm in diameter and transpulmonary fissure abscesses were potential computed tomography imaging-related risk factors for pulmonary abscess-related empyema. Multivariate logistic regression analysis showed that transpulmonary fissure abscesses (odds ratio=9.102, p=0.003), diabetes (odds ratio=9.066, p=0.003), an abscess >5 cm in diameter (odds ratio=8.998, p=0.002), and pleuritic symptoms (odds ratio=5.395, p=0.015) were independent risk factors for pulmonary abscess-related empyema.

CONCLUSIONS

Transpulmonary fissure abscesses, diabetes, giant pulmonary abscesses, and pleuritic symptoms increased the risk of empyema among patients with pulmonary abscesses.

Empyema Necessitans in the Setting of Methicillin-Susceptible Staphylococcus aureus Causing Pneumonia and Bacteremia

Empyema necessitans (EN) is a rare phenomenon that refers to an insidious extension of the empyema through parietal pleura and subsequent dissection into subcutaneous tissue of the chest wall. A 29-year-old man presented to the hospital with fever and chills a few days after an inadvertent needle stick while injecting heroin. His left forearm was warm with an area of fluctuance. He underwent incision and drainage of the left forearm abscess with fluid submitted for Gram stain and culture. His condition rapidly deteriorated due to sepsis, and he required transfer to the intensive care unit. A new 4 × 3 cm area over the left pectoralis muscle had become increasingly indurated, fluctuant, and erythematous. CT of the chest demonstrated extensive cavitary lung lesions and a large loculated left-sided pleural effusion with extension through the chest wall. TEE revealed a 3 cm complex lesion on the superior septal leaflet of the tricuspid valve. The patient underwent incision and drainage of the pectoralis major EN with placement of a drain. Blood and sputum cultures grew methicillin-susceptible Staphylococcus aureus (MSSA) at which time antibiotic therapy was tailored to oxacillin. Our case highlights a rare occurrence of EN due to MSSA in a patient with intravenous drug use (IDU) and underscores the importance of prompt diagnosis and treatment.