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Richard W Light

Publications and source records attributed to Richard W Light.

At least 37 records · Page 2Linked to original sources

Alternative widely available, inexpensive agents for pleurodesis.

PURPOSE OF REVIEW: Pleurodesis is the one of the best options for the management of symptomatic patients with malignant pleural effusion, recurrent benign pleural effusion, and recurrent pneumothorax. Although talc, parenteral tetracycline derivatives, and bleomycin are the most commonly used agents for pleurodesis, parenteral tetracycline derivatives are not available worldwide, bleomycin is expensive, and concerns about the side effects of talc are growing. The purpose of this review is to provide information about other widely available agents for pleurodesis. RECENT FINDINGS: It has recently been shown that oral tetracycline/doxycycline is as effective and safe as parenteral doxycycline in producing pleurodesis in rabbits. SUMMARY: Oral forms of tetracycline derivatives, quinacrine, silver nitrate, iodopovidone, and other talc preparations such as facial talc can be used to create pleurodesis when commonly used agents are not available.

Animals↗

Factors related to recurrence of spontaneous pneumothorax.

OBJECTIVES: The purpose of this retrospective study was to identify factors associated with recurrent spontaneous pneumothorax (SP) in southern China, and to compare the therapeutic effectiveness of different procedures. METHODS: A total of 182 consecutive patients (89.0% male; mean age, 38.9 years), admitted with their first episode of pneumothorax, were reviewed retrospectively. Follow up was available in 138 patients (75.8%), including 68 treated by chemical pleurodesis and 70 by chest tube drainage alone. The cumulative recurrence rates with different therapeutic procedures and different chemical sclerosing agents were compared, and the factors that influenced the recurrence rate were analysed using Cox's proportional hazard model. RESULTS: The most common pre-existing lung disease responsible for pneumothorax was COPD (69.7%), followed by tuberculosis (16.5%). Recurrence was significantly more common in taller patients, patients with lower weight, and patients with secondary spontaneous pneumothorax. The cumulative recurrence rates in the pleurodesis therapy group after 6 months, 1 and 3 years were 13, 16 and 27%, respectively, whereas in the chest tube drainage group the recurrence rates were 26, 33 and 50%, respectively (P < 0.05). There was no significant difference in the recurrence rate for those receiving tetracycline compared with those who received gentamicin. CONCLUSIONS: Spontaneous pneumothorax patients who are taller, weigh less or have secondary spontaneous pneumothorax are more likely to have recurrences. The risk of recurrence is reduced in patients who undergo chemical pleurodesis. Since there was no significant difference between intrapleural tetracycline and gentamicin, gentamicin should be considered as a potential chemical sclerosing agent.

Adult↗

The effects of erythromycin on the viability and the secretion of TNF-alpha and TGF-beta1 and expression of connexin43 by human pleural mesothelial cells.

OBJECTIVE: The mechanism by which erythromycin produces pleurodesis remains unknown. The purpose of this study was to investigate the effects of erythromycin on human pleural mesothelial cell (HPMC) viability, the secretion of tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta(1) (TGF-beta(1)) and the level of expression of connexin43. METHODOLOGY: HPMC were incubated with different concentrations of erythromycin. The inhibitory effects of erythromycin on HPMC growth were measured using a tetrazolium-based colorimetric assay. The levels of TNF-alpha and TGF-beta(1) in supernatants were measured by ELISA and levels of connexin43 were assessed by Western blot. RESULTS: Erythromycin injured HPMC in a dose and time-dependent manner. The secretion of both TNF-alpha and TGF-beta(1) by HMPC increased significantly when they were incubated with 100 mg/L erythromycin for 3 or 5 days. The levels of connexin43 in HPMC decreased after incubation with 100 mg/L erythromycin and no relationship was observed between the levels and incubation time. CONCLUSIONS: Erythromycin injures HPMC in a dose- and time-dependent manner and results in the secretion of TNF-alpha and TGF-beta(1). This is one possible mechanism of pleurodesis with erythromycin. Furthermore, erythromycin decreased the levels of connexin43 in HPMC, which could possibly affect the response of HPMC to pleurodesis with erythromycin.

Analysis of Variance↗

Transforming growth factor-beta3 induces pleurodesis in rabbits and collagen production of human mesothelial cells.

STUDY OBJECTIVE: The aim of this study was to examined whether transforming growth factor (TGF)-beta(3) induces pleurodesis in rabbits and collagen production by human pleural mesothelial cells in vitro. DESIGN: A combined animal and in vitro study. METHODS: TGF-beta(3) was injected intrapleurally in rabbits at the following doses: 0.167 mug, 0.5 mug, 1.67 mug, and 5 mug (five rabbits per group). The rabbits were killed 14 days following injection, and pleurodesis was graded from 1 (none) to 8 (complete symphysis). Pleural mesothelial cell cultures were established from benign pleural effusions and treated with TGF-beta(3) for 48 h at the following doses: 0 (control), 5 ng/mL, 1.5 ng/mL, 5 ng/mL, and 15 ng/mL and 50 ng/mL (two independent experiments). Collagen I messenger RNA (mRNA) expression was quantified using real-time polymerase chain reaction. RESULTS: The median pleurodesis score was 5 (interquartile range [IQR], 4.5) in the 0.167-mug group, 6 (IQR, 5) in the 0.5-mug group, 8 (IQR, 1) in the 1.67-mug group, and 8 (IQR, 0.5) in the 5-mug group (p = 0.012). Higher TGF-beta(3) doses induced the production of significantly more pleural fluid than the lower doses (p = 0.005). The pleural fluid induced by higher doses contained significantly lower numbers of nucleated cells (p = 0.014) and lactate dehydrogenase levels (p = 0.013) than the pleural fluid induced by lower doses of the agent. TGF-beta(3) markedly enhanced collagen I mRNA expression by the human pleural mesothelial cells. This effect peaked at 5 ng/mL TGF-beta(3). With this dose of TGF-beta(3), the collagen I mRNA expression was increased 16-fold over control levels. CONCLUSION: TGF-beta(3) causes a dose-dependent pleurodesis when administered intrapleurally in rabbits, and induces collagen messenger RNA synthesis from human pleural mesothelial cells.

Animals↗

Eotaxin-3 and interleukin-5 pleural fluid levels are associated with pleural fluid eosinophilia in post-coronary artery bypass grafting pleural effusions.

OBJECTIVES: The primary aim of this study was to examine the association between pleural fluid (PF) eosinophilia, and the PF and serum levels of interleukin (IL)-5, eotaxin-2, eotaxin-3, and vascular cell adhesion molecule (VCAM)-1 in patients with post-coronary artery bypass grafting (CABG) pleural effusions. DESIGN: A prospective observational study. SETTING: A tertiary teaching hospital. PATIENTS AND METHODS: Thirty-eight patients with post-CABG pleural effusions were recruited into the study. An effusion that contained at least 10% eosinophils was called "eosinophilic." The PF and serum levels of the cytokines and VCAM-1 were measured using an enzyme-linked immunosorbent assay. RESULTS: (1) The number of PF eosinophils significantly correlated with the number of blood eosinophils. (2) PF IL-5 levels were significantly higher than the corresponding serum levels, and there was a significant correlation between the PF and serum IL-5 levels. PF IL-5 levels significantly correlated with the PF eosinophil count, and serum IL-5 levels significantly correlated with the number of blood eosinophils. (3) PF eotaxin-3 levels were significantly higher than serum levels, and PF eotaxin-3 levels significantly correlated with the PF eosinophil count. (4) PF VCAM-1 levels were significantly lower than the corresponding serum levels, and PF VCAM-1 levels were significantly higher in eosinophilic pleural effusions (EPEs) than in non-EPEs. CONCLUSION: In patients with post-CABG pleural effusions, IL-5 and eotaxin-3 are produced preferentially in the pleural cavity, and they are strongly associated with PF eosinophilia.

Biomarkers↗

Prospective randomized trial of silver nitrate vs talc slurry in pleurodesis for symptomatic malignant pleural effusions.

STUDY OBJECTIVES: To compare the efficacy and the safety of talc slurry and silver nitrate (SN) in the treatment of symptomatic malignant pleural effusions. PATIENTS AND METHODS: Sixty patients were enrolled into the study, and all received a chest tube (26F or 28F) that was placed using local anesthesia. The patients were randomized to receive either 5 g talc diluted to a total volume of 50 mL with saline solution or 20 mL 0.5% SN through the chest tube. Patients were clinically evaluated before and after treatment regarding pain, and were evaluated at monthly intervals with respect to the effectiveness of pleurodesis. Eleven patients did not return for their 30-day follow-up visit and were excluded from further analysis. Pleurodesis therapy was considered to be successful if there was no recurrence of the effusion. The patients who did not have a pleurodesis at one visit were excluded from subsequent visits. RESULTS: Forty-nine patients returned at 30 days for follow-up, including 24 patients who received SN and 25 who received talc. The groups were similar in age (p = 0.23), sex (p = 0.70), Karnofsky index (p = 0.94), and pathology (p = 0.68). After the induction of pleurodesis, neither the total mean (+/- SE) fluid drainage (SN, 901 +/- 125 mL; talc, 766 +/- 74 mL; p = 0.36) nor the level of pain (SN, 2.58 +/- 0.26; talc, 2.62 +/- 0.30; p = 0.91) differed significantly between the groups, and no patient in either group developed ARDS. The mean number of days spent in the hospital was nearly identical (SN group, 3.7 +/- 0.15 days; talc group, 3.6 +/- 0.13 days; p = 0.47). Both SN and talc were effective agents. Thirty days after the procedure, 23 of 24 patients (96%) who had received SN and 21 of 25 patients (84%) who had received talc showed an effective pleurodesis (p = 0.35). Similar results were observed after 60 days (SN group, 18 of 18 patients [100%]; talc group, 13 of 13 patients [100%]; p = > 0.99), 90 days (SN group, 16 of 16 patients [100%]; talc, 8 of 9 patients [89%]; p = 0.36), and 120 days (SN group, 4 of 4 patients [100%]; talc group, 4 of 4 patients [100%]; p > 0.99). CONCLUSIONS: The present study suggests that SN is an effective agent for producing a pleurodesis. In the present study, SN showed a tendency to be more effective than talc, but the power of the test to detect a significance difference was low in this small group of patients. The side effects of 0.5% SN appear to be minimal, but since only a small number of patients received SN and nearly 20% of the patients were lost to follow-up, significant long-term side effects cannot be excluded. Since SN appears to be as effective as talc, and since there is no evidence that it induces ARDS as has been reported with talc, it should be considered as an alternative to talc for the production of a pleurodesis.

Female↗

Efficacy of ultrasound in the diagnosis of pleurodesis in rabbits.

INTRODUCTION: The treatment of recurrent pleural effusion or recurrent pneumothorax frequently involves the creation of a pleurodesis. Ultrasound is being used more frequently to assess the presence of pleural fluid or pneumothorax. With ultrasound, the gliding sign displays the gliding of the visceral pleura over the parietal pleura during respiration. The absence of a gliding sign is indicative of a pneumothorax. HYPOTHESIS: We hypothesized that the presence of pleurodesis would be indicated by the absence of a gliding sign on ultrasound. METHODS: To create a pleurodesis, a single intrapleural injection of transforming growth factor-beta2 at a dosage of 1.70 microg/kg or doxycycline at a dosage of 10 mg/kg in a volume of 2.0 mL was administered randomly to one side of a New Zealand White rabbit. Prior to death on day 14 after intrapleural injection, all rabbits underwent an ultrasonic examination at three marked sites on each side of the chest. At each site, three ultrasonic features (gliding sign, pleural thickening, and pleural effusion) were evaluated and graded. The gliding sign was graded as follows: 0 = gliding sign definitely present, 1 = gliding sign questionable, 2 = gliding sign absent. RESULTS: In a preliminary study for developing skill in assessing the gliding sign, the correlation between the gliding sign and the pleurodesis score in 16 rabbits was highly significant (r = 0.568, p = 0.02). In the subsequent main study with 18 additional rabbits, the correlation between the gliding sign score and the pleurodesis score was even better (r = 0.806, p = 0.00009). The gliding sign was definitely present on the noninjected side in all rabbits. CONCLUSIONS: The presence of a pleurodesis is indicated by the absence of a pleural guiding sign on ultrasound.

Animals↗

Pleurodesis is inhibited by anti-vascular endothelial growth factor antibody.

STUDY OBJECTIVES: The intrapleural injection of transforming growth factor (TGF)-beta2 produces pleurodesis in rabbits associated with large pleural effusions. This study investigated whether anti-vascular endothelial growth factor (VEGF) antibody has any effect on the fluid production or the pleurodesis induced by TGF-beta2. INTERVENTIONS AND MEASUREMENTS: Three groups of seven New Zealand white rabbits were administered TGF-beta2 5.0 microg intrapleurally. Two groups received anti-VEGF antibody (10 mg/kg and 25 mg/kg) IV 24 h before TGF-beta2 injection, and the third group received no antibody. The rabbits were killed at 2 weeks, and the macroscopic pleurodesis score was determined. The degree of pleural angiogenesis was assessed by immunohistochemical staining for factor VIII. RESULTS: The administration of anti-VEGF antibodies had no significant effect on the pleural fluid volume or the characteristics of the fluid. The mean pleurodesis score of the seven rabbits in the control group (7.71 +/- 0.76) was significantly (p < 0.05) higher than that for seven rabbits in the low-dose treatment group (4.43 +/- 2.37) and the seven rabbits in the high-dose treatment group (4.57 +/- 2.36) [+/- ]. The percentage of pleural tissue demonstrating angiogenesis in the control group (4.87 +/- 0.43%) was significantly (p < 0.05) higher than that for the low-dose (2.94 +/- 0.68%) or high-dose (2.67 +/- 0.64%) antibody groups. When all rabbits were considered, there was a highly significant correlation between the pleural vascular density scores and the pleurodesis scores (r = 0.84, p < 0.01). CONCLUSION: VEGF and angiogenesis appear to play a pivotal role in the production of a pleurodesis.

Animals↗

Intrapleural low-dose silver nitrate elicits more pleural inflammation and less systemic inflammation than low-dose talc.

STUDY OBJECTIVES: Several systemic effects have been described after talc pleurodesis. The aim of this study was to assess the systemic response induced by low, nonpleurodesis-inducing doses of talc and silver nitrate in an experimental model in rabbits. DESIGN: Groups of six rabbits were injected intrapleurally with talc, 100 mg/kg or 400 mg/kg, and silver nitrate, 0.1% or 0.5%. After 6, 24, or 48 h, samples of blood and pleural fluid were collected and assayed for leukocytes, percentage of neutrophils, lactate dehydrogenase, interleukin-8, and vascular endothelial growth factor (VEGF) levels. Preinjection blood samples were used as normal blood controls. MEASUREMENTS AND RESULTS: Silver nitrate 0.1% induced a more intense pleural inflammation than that produced by talc 100 mg/kg. In contrast, talc 100 mg/kg induced a more pronounced acute systemic response with higher values of WBCs and neutrophils, whereas silver nitrate 0.1% produced no significant increases in leukocytes or neutrophils. The serum interleukin-8 and VEGF levels increased in all groups, and decreased with time only in the silver nitrate 0.1% group. The highest serum VEGF levels were observed in the talc 100 mg/kg group. CONCLUSIONS: In conclusion, 0.1% silver nitrate produced an intense pleural inflammatory response with a less evident systemic response in comparison to 0.5% silver nitrate and talc 100 mg/kg or 400 mg/kg.

Animals↗

Pneumothorax-associated pleural eosinophilia in mice is interleukin-5 but not interleukin-13 dependent.

STUDY OBJECTIVES: To establish a murine model of pneumothorax-associated pleural eosinophilia and to examine the role of interleukin (IL)-5 and IL-13 in the pathogenesis of this reaction. DESIGN: An animal study. INTERVENTIONS: One hundred thirty-seven C57/Bl-6 mice were used in this study. Wild-type animals were injected intrapleurally with 0.4 mL of air and were killed at different time points (30 min to 7 days) after the injection. IL-5 knockout and IL-13 knockout animals were killed 24 h and 48 h after the injection. Pleural inflammation was assessed by pleural lavage (PL). MEASUREMENTS AND RESULTS: PL cells were significantly increased following the induction of pneumothorax. The peak number of neutrophils, observed at 12 h, was 900 times higher than the control. The peak number of eosinophils, observed at 48 h, was 700 times higher than the control. Lymphocytes and mononuclear cells increased threefold and fourfold, respectively. IL-5 knockout mice had significantly less PL eosinophils than that the wild-type or the IL-13 knockout mice at 24 h (150 +/- 46/microL, 903 +/- 244/microL, and 912 +/- 168/microL, respectively; p = 0.013) and 48 h (181 +/- 45/microL, 1,587 +/- 212/microL, and 1,379 +/- 364/microL, respectively; p = 0.003). CONCLUSION: Pneumothorax induces an inflammatory reaction of the mouse pleura, mainly characterized by increased neutrophils and eosinophils. IL-5 but not IL-13 is required for pneumothorax-associated pleural eosinophilia.

Animals↗

Combination therapy with intrapleural doxycycline and talc in reduced doses is effective in producing pleurodesis in rabbits.

BACKGROUND: It has been suggested that talc and doxycycline might be acting through different pathways in creating pleurodesis. We hypothesized that combining doxycycline and talc in half the usual doses would be synergistic in inducing pleurodesis. METHODS: Thirty-two rabbits were equally allocated into four groups: group 1, half-dose combination (5 mg/kg of doxycycline and 200 mg/kg of talc slurry); group 2, quarter-dose combination (2.5 mg/kg of doxycycline and 100 mg/kg of talc slurry); group 3, half-dose doxycycline (5 mg/kg of doxycycline); and group 4, half-dose talc (100 mg/kg of talc slurry). The pleurodesis scores from historical groups that received a full dose of talc (400 mg/kg) or doxycycline (10 mg/kg) were also compared to those obtained in the current study. Pleural fluid lactate dehydrogenase and protein levels were measured 24 h after the injection. Pleurodesis was graded from 1 (none) to 8 (> 50% symphysis) by two observers blinded to treatment groups. All rabbits underwent an ultrasonic examination on each side of their chest for the evaluation of pleurodesis. RESULTS: The mean pleurodesis score in the half-dose combination group was significantly higher than that in the half-dose talc group, half-dose doxycycline group, and the historical full-dose talc group (p = 0.009, p = 0.01, and p < 0.05, respectively). The quarter-dose combination group also had a significantly higher mean pleurodesis score compared to the half-dose talc group (p = 0.013). The difference between the historical full-dose doxycycline and the half-dose combination or quarter-dose combination groups was not significant (p > 0.05). A significantly positive correlation existed between the pleurodesis score and the ultrasound scores (r = 0.876, p = 0.000000005). CONCLUSIONS: This study demonstrates that the combination of half doses of talc and doxycycline is more effective than the half dose of either drug alone or the full dose of talc in producing pleurodesis in rabbits. In addition, ultrasound is an accurate imaging modality for the evaluation of pleurodesis, in that the absence of pleural gliding on ultrasound correlates well with the presence of a pleurodesis in rabbits.

Animals↗

Oral forms of tetracycline and doxycycline are effective in producing pleurodesis.

PURPOSES: We investigated whether oral tetracyclines could produce an efficient and safe pleurodesis as does parenteral doxycycline, which is currently unavailable in many countries. METHODS: Parenteral doxycycline (10 mg/kg), oral tetracycline (35 mg/kg), or doxycycline (10 mg/kg) was injected intrapleurally through a right chest tube in rabbits. The oral forms were dissolved in saline solution and passed through a sterile membrane filter. When daily aspirated pleural fluid was < 5 mL/24 h, the chest tube was removed. Fluid WBC, lactate dehydrogenase (LDH), and protein levels were measured 24 h after the injection. After the death of the animals on day 14, pleurodesis was graded from 1 (none) to 8 (> 50% symphysis) by two observers blinded to treatment groups. RESULTS: The right pleurodesis score of the combined oral groups (median, 7.0; interquartile range [IQR], 4.0; n = 26) did not differ significantly (p = 0.349) from that of the parenteral group (median, 7.5; IQR, 6.0; n = 10). Oral tetracycline (capsule or tablet, n = 6 in each group) and doxycycline (capsule or tablet, n = 7 in each group) were as effective as parenteral doxycycline in producing pleurodesis: tetracycline capsule (median, 7.50; IQR, 6.00); tetracycline tablet (median, 6.50; IQR, 6.00); doxycycline capsule (median, 4.00; IQR, 1.00); doxycycline tablet (median, 8.00; IQR, 5.00), and parenteral doxycycline (median, 7.50; IQR, 6.00) [p = 0.235]. The left pleurodesis scores were 1.00 in all 36 rabbits. Fluid total volume, WBC, LDH, and protein levels were comparable between each oral and parenteral group, excluding WBCs in the tetracycline tablet group (p = 0.047). The complications were nonfatal (right hemothorax: tetracycline capsule [n = 3]/tetracycline tablet [n = 2], doxycycline tablet [n = 2], parenteral doxycycline [n = 2]; left hemothorax: tetracycline capsule [n = 1]; ascites: parenteral doxycycline [n = 1]). There was no growth on all filtrate cultures. Oral forms cost less than parenteral doxycycline (<1 US dollar vs 4.72 US dollars per rabbit). Filtering costs were 1.12 US dollars per rabbit. CONCLUSION: Oral tetracycline or doxycycline is as effective and safe as parenteral doxycycline in producing pleurodesis in rabbits; thus, they may also be used in humans.

Administration, Oral↗

[Heparin induced thrombocytopenia: how to manage when the patient is pregnant?].

Immune mediated heparin induced thrombocytopenia (HIT) remains the most common anti-body mediated, drug-induced thrombocytopenic disorder, and a leading cause of morbidity and mortality. Management of HIT in pregnant women remains uncertain. In this article, HIT in general, and special conditions and management issues in pregnant women discussed and the related literature reviewed.

Anticoagulants↗

[Indwelling catheter for the management of malign pleural effusions].

Symptomatic malignant pleural effusions are most commonly managed by chemical pleurodesis. The primary disadvantage of chemical pleurodesis is that it requires hospitalization for approximately five days. An alternative to chemical pleurodesis is insertion of an indwelling catheter, which can be applied easily on an outpatient basis. Pleural fluid is drained at 24 to 48 hour intervals by inserting an external line connected to a vacuum container. In the present time, indwelling catheters are viable alternatives for the management of symptomatic malignant pleural effusions especially when length of hospitalization is to be kept to a minimum, and expertise and facilities exist outpatient management of these catheters.

Catheterization↗

Activation of proteinase-activated receptor-2 in mesothelial cells induces pleural inflammation.

Pleural inflammation underlies many pleural diseases, but its pathogenesis remains unclear. Proteinase-activated receptor-2 (PAR(2)) is a novel seven-transmembrane receptor with immunoregulatory roles. We hypothesized that PAR(2) is present on mesothelial cells and can induce pleural inflammation. PAR(2) was detected by immunohistochemistry in all (19 parietal and 11 visceral) human pleural biopsies examined. In cultured murine mesothelial cells, a specific PAR(2)-activating peptide (SLIGRL-NH(2)) at 10, 100, and 1,000 muM stimulated a 3-, 42-, and 1,330-fold increase of macrophage inflammatory protein (MIP)-2 release relative to medium control, respectively (P < 0.05 all) and a 2-, 32-, and 75-fold rise over the control peptide (LSIGRL-NH(2), P < 0.05 all). A similar pattern was seen for TNF-alpha release. Known physiological activators of PAR(2), tryptase, trypsin, and coagulation factor Xa, also stimulated dose-dependent MIP-2 release from mesothelial cells in vitro. Dexamethasone inhibited the PAR(2)-mediated MIP-2 release in a dose-dependent manner. In vivo, pleural fluid MIP-2 levels in C57BL/6 mice injected intrapleurally with SLIGRL-NH(2) (10 mg/kg) were significantly higher than in mice injected with LSIGRL-NH(2) or PBS (2,710 +/- 165 vs. 880 +/- 357 vs. 88 +/- 46 pg/ml, respectively; P < 0.001). Pleural fluid neutrophil counts were higher in SLIGRL-NH(2) group than in the LSIGRL-NH(2) and PBS groups (by 40- and 26-fold, respectively; P < 0.05). This study establishes that activation of mesothelial cell PAR(2) potently induces the release of inflammatory cytokines in vitro and neutrophil recruitment into the pleural cavity in vivo.

Animals↗

Pathogenesis of the eosinophilic pleural effusions.

PURPOSE OF REVIEW: Eosinophilic pleural effusions (EPE) are defined as those that contain at least 10% eosinophils. EPEs account for 5 to 16% of exudative pleural effusions. However, their pathogenesis is poorly understood. The purpose of this review is to discuss the mechanisms that lead to eosinophilic pleural inflammation. RECENT FINDINGS: Eosinophilic pleural effusions are caused by the presence of air or blood or both in the pleural space, infectious or other inflammatory diseases, malignancy, pulmonary emboli, asbestos exposure, and drug reactions. Differences in the clinical features suggest that a variety of mechanisms operate to induce eosinophilic pleural inflammation and pleural fluid accumulation. Human and animal studies indicate that interleukin (IL)-5 is an important common contributor of different pathogenetic pathways. The possible role of other cytokines, chemokines, and adhesion molecules in the development of EPE is under investigation. SUMMARY: Understanding the pathogenesis of EPE will permit the development of novel therapies for the persistent, symptomatic, posttraumatic and idiopathic EPE. Anti-IL-5 treatment is an interesting option that requires further research.

Animals↗

Management of malignant pleural effusions.

Malignant pleural effusion is a common clinical problem. Evacuation of the pleural fluid and prevention of its reaccumulation are the main aims of management. Pleurodesis should be attempted early, although considerable practice variations exist in the way it is performed. There is a lack of consensus among respiratory physicians worldwide on the optimal method and agent for pleurodesis. Talc remains the most commonly used pleurodesing compound in most countries. While talc produces a higher success rate than other compounds, it generates more side-effects. The association between talc and ARDS continues to be debated. Ambulatory small-bore pleural catheter drainage followed by intrapleural instillation of a pleurodesing agent is increasingly accepted as an alternative to conventional in-patient pleurodesis. Development of novel methods to control pleural fluid formation should be made a high priority in future pleural research.

Humans↗

Talc and silver nitrate induce systemic inflammatory effects during the acute phase of experimental pleurodesis in rabbits.

STUDY OBJECTIVE: s: To determine whether talc (TL) and silver nitrate (SN), two effective pleurodesis agents, induce a systemic inflammatory response in the acute phase of experimental pleurodesis in rabbits. DESIGN: Samples of blood and pleural fluid were collected after 6, 24, and 48 h from rabbits injected intrapleurally with 3 mL saline solution, TL (400 mg/kg), or 0.5% SN, and were assayed for WBC count, percentage of neutrophils, and levels of lactate dehydrogenase (LDH), interleukin (IL)-8, and vascular endothelial growth factor (VEGF). The pleural liquid production was compared in the three different groups. A sample of blood collected from animals preinjection was used as the control. RESULTS: At 6 h after pleural injection, the mean blood WBC count and percentage of neutrophils were significantly elevated in the TL group, whereas the mean LDH and IL-8 levels were significantly increased in the SN group. VEGF was undetectable in the preinjection serum and saline solution-injected animals, but was increased in the serum after the pleural injection of both TL and SN to a comparable degree. SN elicited a more intense acute pleural inflammation reaction than did TL, with higher WBC count and IL-8 levels found in the pleural fluid, mainly within the first 6 h. LDH and VEGF levels, and pleural liquid production were also higher for SN, and they increased with time. CONCLUSIONS: In the acute phase of pleural injection, TL induced a transient increase in blood WBC count and percentage of neutrophils, while SN induced increases in blood LDH and IL-8 levels. Both TL and SN induced significant increases in blood VEGF levels. SN induced an earlier and more intense acute pleural inflammation than TL. Pleural liquid VEGF levels were higher after SN injection and increased, as did pleural liquid production. These findings suggest that the intrapleural injection of TL and SN produce a systemic inflammatory response that may have a role in the pathogenesis of fever and ARDS, which occur with pleurodesis.

Acute Disease↗