Diagnosis of pleural infection: state-of-the-art

Incidental Extraspinal Findings in the Thoracic Spine during Magnetic Resonance Imaging of Intervertebral Discs

Objective:

The purpose of this research was to determine the frequency of incidental extraspinal findings in the thoracic spine on magnetic resonance imaging (MRI).

Materials and Methods:

A total of 120 thoracic spine MRI patients were prospectively examined in the period extending from August 2018 to April 2019. Both 1.5 and 0.35 Tesla MRI systems (Toshiba and Siemens Medical system) were applied to investigate patients with suspected intervertebral disc abnormalities at three MRI diagnostic centers in Khartoum, Sudan.

Results:

Out of the 120 patients, incidental extraspinal findings were found in 16 patients (13.3%). Various incidental findings (IFs) were seen, including renal cysts, liver mass, thyroid goiter, and pleural effusion. Out of these IFs, 37.5% were considered clinically significant.

Conclusions:

Various IFs were identified during a routine thoracic spine MRI, and approximately one-third of them were clinically significant. Therefore, it is essential for the reporting radiologists to pay attention to extraspinal findings while reporting thoracic spine MRI to avoid missing clinically significant findings.

Safety and Efficacy of Intrapleural Tissue Plasminogen Activator and DNase during Extended Use in Complicated Pleural Space Infections

The use of intrapleural therapy with tissue plasminogen activator and DNase improves outcomes in patients with complicated pleural space infections. However, little data exists for the use of combination intrapleural therapy after the initial dosing period of six doses. We sought to describe the safety profile and outcomes of intrapleural therapy beyond this standard dosing. A retrospective review of patients receiving intrapleural therapy with tissue plasminogen activator and DNase was performed at two institutions. We identified 101 patients from January 2013 to August 2015 receiving intrapleural therapy for complicated pleural space infection. The extended use of intrapleural tissue plasminogen activator and DNase therapy beyond six doses was utilized in 20% (20/101) of patients. The mean number of doses in those undergoing extended dosing was 9.8 (range of 7–16). Within the population studied there appears to be no statistically significant increased risk of complications, need for surgical referral, or outcome differences when comparing those receiving standard or extended dosing intrapleural therapy. Future prospective study of intrapleural therapy as an alternative option for patients who fail initial pleural drainage and are unable to tolerate/accept a surgical intervention appears a potential area of study.

Distinguishing complicated from uncomplicated parapneumonic effusions

PURPOSE OF REVIEW

Treatment of parapneumonic effusions (PPEs) is challenged by the decision of whether or not to insert chest tubes. This review focuses on the factors that may aid in determining which patients require an immediate drainage of the pleural space, that is, have a complicated PPE.

RECENT FINDINGS

Clinical guidelines advocate the evaluation of radiological (large effusion or loculation), bacteriological (Gram-positive stain or culture), biochemical (pH < 7.20 or glucose <60 mg/dl), and macroscopic (pus) characteristics of the pleural fluid to assist in the identification of complicated PPEs. In the past few years, a number of new pleural fluid biomarkers have been tested for the same purpose, but with the exception of C-reactive protein (CRP), they should be considered investigative. A pleural fluid CRP higher than 100 mg/l or a serum CRP higher than 200 mg/l, when combined with pleural fluid pH or glucose, may greatly increase our capability to predict the need for instituting tube thoracostomy. Although some ultrasonographic and computed tomography features favor the diagnosis of pleural infection, their role in uncomplicated-complicated PPE discrimination has not been systematically evaluated.

SUMMARY

No pleural fluid tests, other than pH or glucose, have gained wide acceptance for the assessment of patients with PPE. However, if corroborated with further studies, the measurement of pleural fluid or serum CRP, in combination with the classical fluid parameters, may have the potential to be incorporated into medical decision making.

Pleural fluid biomarkers: beyond the Light criteria

Although distinguishing transudates from exudates through the Light criteria is still considered a pragmatic first step in the diagnostic work-up of pleural effusions, the measurement of various pleural fluid biomarkers may aid in the identification of common and specific entities, such as heart failure (natriuretic peptides), tuberculosis (adenosine deaminase), malignancy (mesothelin, fibulin-3, immunocytochemical stains), or bacterial pleural infections (C-reactive protein). The use of these biomarkers is currently encouraged as a routine diagnostic procedure.

Emergencies in pleural diseases

A parapneumonic effusion should be drained if it is large (≥ 1/2 of the hemithorax), loculated, frank pus is obtained, if the fluid is non-purulent fluid but has a low pH (< 7.20) or if the culture is positive. Instillation of fibrinolytics and DNase thorough the chest catheter in locutated effusions and empyemas is currently recommended. Management of spontaneous pneumothorax is fundamentally influenced by the patient's symptoms. Insertion of a chest catheter is mandatory if there is significant dyspnea, hemodynamic instability or large pneumothoraces (≥ 2 cm). Pleural ultrasonography confirms the presence of air or fluid in the pleural space and serves to guide any pleural procedure (e.g., thoracentesis, chest tubes). The use of small-bore 12F catheters inserted via the percutaneous Seldinger technique under ultrasonography guidance is a safe and effective procedure in complicated parapneumonic effusions/empyema and most pneumothoraces.