Management of undiagnosed persistent pleural effusions

Urinothorax: Case report and systematic review of the literature

Urinothorax, the presence of urine in the pleural space, is a rare cause of pleural effusion, usually associated with obstructive uropathy, or urinary trauma. We present the case of a 3 year-old boy and a systematic review of the literature of the 44 cases encountered. After resection of a Wilm's tumour in the right kidney our patient presented acute respiratory distress associated with radiographically confirmed pleural effusion. With the initial diagnosis of pneumonia or malignant pleural effusion, a closed thoracotomy was performed. The liquid obtained suggested urine, which was confirmed by the laboratory. Cystoscopy with retrograde pyelography detected a fistula on the posterior wall of the right kidney. The report of cases worldwide is low, probably due to its low incidence but also to underdiagnosis. Respiratory symptoms are not always present and urological symptoms usually predominate. Diagnosis requires a high degree of clinical suspicion and is confirmed by the main biochemical marker: The ratio >1.0 pleural fluid creatinine and creatinine serum.

Utility of semi-rigid thoracoscopy in undiagnosed exudative pleural effusion

Background:

Semi-rigid thoracoscopy is a safe and efficacious procedure in patients with undiagnosed pleural effusion. Literature on its utility from developing countries is limited. We herein describe our initial experience on the utility of semi-rigid thoracoscopy from a tertiary care teaching and referral center in north India. We also perform a systematic review of studies reporting the utility of semi-rigid thoracoscopy from India.

Patients and Methods:

The primary objective was to evaluate the diagnostic utility of semi-rigid thoracoscopy in patients with undiagnosed exudative pleural effusion. Semi-rigid thoracoscopy was performed under local anesthesia and conscious sedation in the bronchoscopy suite.

Results:

A total of 48 patients underwent semi-rigid thoracoscopy between August 2012 and December 2013 for undiagnosed pleural effusion. Mean age was 50.9 ± 14.1 years (range: 17–78 years). Pre-procedure clinico-radiological diagnoses were malignant pleural effusion [36 patients (75%)], tuberculosis (TB) [10 (20.83%) patients], and empyema [2 patients (4.17%)]. Patients with empyema underwent the procedure for pleural biopsy, optimal placement of intercostal tube and adhesiolysis. Thoracoscopic pleural biopsy diagnosed pleural malignancy in 30 (62.5%) patients and TB in 2 (4.17%) patients. Fourteen (29.17%) patients were diagnosed with non-specific pleuritis and normal pleura was diagnosed on a pleural biopsy in 2 (4.17%) patients. Overall, a definitive diagnosis of either pleural malignancy or TB was obtained in 32 (66.7%) patients. Combined overall sensitivity, specificity, positive predictive value and negative predictive value of thoracoscopic pleural biopsy for malignant pleural effusion were 96.77%, 100%, 100% and 66.67%, respectively. There was no procedure-related mortality. On performing a systematic review of literature, four studies on semi-rigid thoracoscopy from India were identified.

Conclusion:

Semi-rigid thoracoscopy is a safe and efficacious procedure in patients with undiagnosed exudative pleural effusions.

A stepwise approach to the etiologic diagnosis of pleural effusion in respiratory intensive care unit and short-term evaluation of treatment

Background:

Pleural effusions in respiratory intensive care unit (RICU) are associated with diseases of varied etiologies and often carry a grave prognosis. This prospective study was conducted to establish an etiologic diagnosis in a series of such patients before starting treatment.

Materials and Methods:

Fifty consecutive patients, diagnosed with pleural effusion on admission or during their stay in RICU, were further investigated by a two-step approach. (1) Etiologic diagnosis was established by sequential clinical history and findings on physical examination, laboratory tests, chest radiograph, CECT/HRCT/PET-CT and pleural fluid analysis. (2) Patients who remained undiagnosed were subjected to fiber-optic bronchoscopy, video-assisted thoracoscopic pleural biopsy, and histopathology.

Results:

Etiologic diagnosis of pleural effusion was established in 44 (88%) Metastases (24%); para-pneumonia (22%); congestive cardiac failure (18%); tuberculosis (14%); hemothorax (4%); trapped lung, renal failure, and liver cirrhosis (2% each). Six patients (12%) remained undiagnosed, as the final diagnostic thoracoscopic biopsy could not be performed in five and tissue histopathology findings were inconclusive in one. Out of the 50 patients, 10 died in the hospital; 2 left against medical advice; and 2 were referred to oncology center for further treatment. The remaining 36 patients were clinically stabilized and discharged. During a 3-month follow-up, eight of them were re-hospitalized, of which four died.

Conclusions:

Pleural effusion in RICU carries a high risk of mortality. Etiologic diagnosis can be established in most cases.

The diagnosis and management of pleural effusions in the ICU

Pleural effusions are common in critically ill patients. Most effusions in intensive care unit (ICU) patients are of limited clinical significance; however, some are important and require aggressive management. Transudative effusions in the ICU are commonly caused by volume overload, decreased plasma oncotic pressure, and regions of altered pleural pressure attributable to atelectasis and mechanical ventilation. Exudates are sequelae of pulmonary or pleural infection, pulmonary embolism, postsurgical complications, and malignancy. Increases in pleural fluid volume are accommodated principally by chest wall expansion and, to a lesser degree, by lung collapse. Studies in mechanically ventilated patients suggest that pleural fluid drainage can result in improved oxygenation for up to 48 hours, but data on clinical outcomes are limited. Mechanically ventilated patients with pleural effusions should be semirecumbant and treated with higher levels of positive-end expiratory pressure. Rarely, large effusions can cause cardiac tamponade or tension physiology, requiring urgent drainage. Bedside ultrasound is both sensitive and specific for diagnosing pleural effusions in mechanically ventilated patients. Sonographic findings of septation and homogenous echogenicity may suggest an exudative effusion, but definitive diagnosis requires pleural fluid sampling. Thoracentesis should be carried out under ultrasound guidance. Antibiotic regimens for parapneumonic effusions should be based on current pneumonia guidelines, and anaerobic coverage should be included in the case of empyema. Decompression of the pleural space may be necessary to improve respiratory mechanics, as well as to treat complicated effusions. While small-bore catheters inserted under ultrasound guidance may be used for nonseptated effusions, surgical consultation should be sought in cases where this approach fails, or where the effusion appears complex and septated at the outset. Further research is needed to determine the effects of pleural fluid drainage on clinical outcomes in mechanically ventilated patients, to evaluate weaning strategies that include pleural fluid drainage, and to better identify patients in whom pleural effusions are more likely to be infected.

Diagnosis of pleural effusion: a systematic approach

In most diseases related to pleural effusion, the fluid analysis yields important diagnostic information, and in certain cases, fluid analysis alone is enough for diagnosis. The many important characteristics of pleural fluid are described, as are other complementary investigations that can assist with the diagnosis of common and rare pleural effusions. For a systematic review of pleural effusion, a literature search for articles on the practical investigation and diagnosis of pleural effusion was done. Articles included guidelines, expert opinion, experimental and nonexperimental studies, literature reviews, and systematic reviews published from May 2003 through June 2009. The search yielded 1 guideline, 2 meta-analyses, 9 literature reviews, 1 randomized control trial, and 9 clinical studies. On the basis of class IIa or class I evidence from these articles, a step by step approach is recommended for investigating a pleural effusion, beginning with assessment of the medical history, clinical examination, radiology, pleural fluid evaluation, and finally, if no diagnosis is forthcoming, a pleural biopsy under image guidance or thoracoscopy.

Pleural fluid characteristics of tuberculous pleural effusions

Mycobacterium tuberculosis (TB) infection of the pleural space is an important cause of pleural effusion in areas of high TB prevalence. Microbiological analyses of pleural fluid in the acute setting may be negative. Consequently, investigations may proceed to more invasive techniques, such as pleural biopsy or thoracoscopy. Ongoing research has led to implementing a number of additional fluid analyses that may lead to a diagnosis without a need for further invasive procedures. In this review, we discuss the characteristics of tuberculous pleural fluid that may assist in this important diagnosis, and we highlight the benefits of specific biomarker analyses. English-language publications from a MEDLINE search and references from relevant articles from January 1, 1990 to September 1, 2009 were reviewed. The key words searched included tuberculosis, pleural fluid, effusion, diagnosis, adenosine deaminase, and interferon.

A systematic approach to the investigation and diagnosis of a unilateral pleural effusion

Fluid in the pleural space is a common sequela of a wide range of diseases which may be pulmonary, pleural or extrapulmonary. As the differential diagnosis is wide, a systematic approach to investigation and diagnosis is recommended. This review highlights the important features and recommendations for the investigation of a unilateral pleural effusion, a common condition encountered by the general physician. The aim of this study was to assist with a speedy diagnosis of the underlying pathology, using appropriate investigative techniques, while minimising the use of invasive procedures.

Adjustments of serum lactate dehydrogenase isoenzymes and their significance in monitoring the treatment in patients with tubercular pyothorax

The adjustments and diagnostic significance of polyacrylamide gel electrophoretic (PAGE) profiles of lactate dehydrogenase isoenzymes (LDH: 1.1.1.27) was evaluated in the sera and pleural fluid of patients with tubercular pyothorax. Sera and pleural fluid samples were randomly collected from 72 and 18 patients respectively at two different timings; first, when patients were admitted to the Hospital and second, after an intensive phase of treatment. Sera of 20 healthy individuals served as control. Our results demonstrate significant differences in sera LDH (sLDH) and pleural fluid LDH (pfLDH) isoenzymes. In patients the order of LDH isoenzyme in sera and pleural fluid followed: LDH-5>-4>-2>-3>-1 and LDH-5>-4>-3>-2>-1 respectively. The ranking of activity levels in control was LDH-2>-1>-3>-5>-4. In the second phase of sampling from 31 patients, values of sLDH isoenzymes showed recovery and resembled profiles of controls. Therefore, the sLDH zymograms of patients can be used as the prognostic marker, since they tend to reach the normal level during recovery signifying the effect of chemotherapy in hospitalized patients. Moreover, according to the present findings on LDH-PAGE profiles, the levels of LDH-5 and-4 rise in pyothorax patients significantly (P<0.05). This elevation along with the rise in total LDH activity may, therefore, be used in the diagnosis and monitoring of tubercular pyothorax.

[Diagnosis and management of pleural effusions in critically iII patients]

INTRODUCTION

Pleural effusions are common in ICU patients. Causes include massive fluid resuscitation in shock, pneumonia--either community acquired or nosocomial, cardiac insufficiency, hypoalbuminemia and hepatic impairment. Pleural effusions frequently complicate cardiac and abdominal surgery and haemothorax may complicate trauma.

STATE OF THE ART

The incidence of pleural effusions in the intensive care unit (ICU) varies depending on the screening method used, from about 8% for physical examination to more than 60% for routine ultrasonography. In the absence of clinical parameters to exclude infection pleurocentesis remains an essential aspect of management and is not contraindicated mechanical ventilation. This review of the diagnosis and management of pleural effusions in ICU patients reports the most recent data from the literature. Pleurocentesis can be performed safely in the ICU, even in mechanically ventilated patients. The absence of reliable clinical or laboratory test criteria for determining the cause of pleural effusions and the potentially devastating consequences of failing to diagnose and treat pleural infection are strong reasons to perform pleurocentesis in patients with clinically detectable pleural effusions and no contraindication to the procedure.

PERSPECTIVES

Although the data reviewed indicate that the diagnosis and treatment of pleural effusions should follow the same rules in the ICU as they do elsewhere, several incompletely resolved issues deserve further investigation. These are summarised in an agenda for future research.

Pleural effusion

Pleural disease remains a commonly encountered clinical problem for both general physicians and chest specialists. This review focuses on the investigation of undiagnosed pleural effusions and the management of malignant and parapneumonic effusions. New developments in this area are also discussed at the end of the review. It aims to be evidence based together with some practical suggestions for practising clinicians.

Pleural effusions in the intensive care unit

The incidence of pleural effusions in the intensive care unit varies depending on the screening methods, from approximately 8% for physical examination to more than 60% for routine ultrasonography. Several factors contribute to the occurrence of pleural effusions in intensive care unit patients: large amounts of intravenous fluid are often administered, pneumonia is common, and heart failure, atelectasis, extravascular catheter migration, hypoalbuminemia, or liver disease are present in many intensive care unit patients. In surgical intensive care units, cardiac or abdominal surgery is often followed by pleural effusions, and in trauma patients, hemothorax is a dreaded event. Because no clinical parameter excludes pleural infection, and because of the impact of thoracentesis on diagnosis and treatment, this procedure should be performed unless contraindicated. Thoracentesis is safe in mechanically ventilated patients. The author discusses the following points regarding pleural effusions in the intensive care unit: screening intensive care unit patients for pleural effusion, safety of thoracentesis in patients receiving invasive mechanical ventilation, distinguishing exudates from transudates, and diagnosing and managing infected pleural effusions in critically ill patients. Lastly, the author suggests a research agenda for pleural effusions in intensive care unit patients.