Diagnostic utility of eosinophils in the pleural fluid

Valproic acid-induced eosinophilic pleural effusion: An uncommon occurrence

A 43-year-old male using valproic acid (VA) for 2 years for seizure disorder presented with right-sided moderate pleural effusion. Pleural fluid analysis revealed exudative effusion with 42% eosinophils. There was no evidence of haemothorax, pneumothorax, malignancy, and parasitic infections. Suspecting a drug-related event, VA was discontinued. The patient showed clinical improvement with resolution of pleural effusion on chest radiograph three weeks later. VA is a popular drug used for variety of disorders like seizures, migraines, and schizophrenia. There is a paucity of literature on VA-induced pleural effusion. Though a rare phenomenon, clinicians should be aware of such a possibility to avoid erroneous diagnosis.

Incidence, aetiology and clinical features of eosinophilic pleural effusion: a retrospective study

Background

Eosinophilic pleural effusion (EPE) is a distinct entity among pleural effusions, but its diagnostic and prognostic significance is still controversial. This study aimed to evaluate the incidence and aetiological distribution of EPE in our institution and to assess the relationship between EPE and malignancy and other underlying diseases and the relevance of the percentage of eosinophils and other laboratory parameters.

Methods

A retrospective study was conducted by reviewing the medical records of 252 patients with PE from September 2017 to January 2021.

Results

EPE was found in 34 (13.49%) out of 252 patients. There were 20 (58.82%) males and 14 (41.18%) females in the EPE group. The mean percentage of eosinophils in EPE (21.7%, range (10.0–67.5%)) was significantly higher than the percentage of eosinophils in peripheral blood (5.65%, range (0–34.60%); p < 0.05). The most common cause of EPE was malignant disease (52.94%), followed by idiopathy (14.71%), parasites (8.82%), pneumonia (8.82%) and others (14.71%). Comparative analysis of patients with malignant versus nonmalignant EPE showed that patients with malignant EPE were significantly older, and had a lower white blood cell (WBC) count in the pleural fluid (1.8 vs 4.7 cells × 10⁹/L, p < 0.05). However, the percentage of eosinophils in PE was not significantly different between malignant EPE and nonmalignant EPE (p = 0.66). There was no correlation between the percentage of eosinophils in PE and peripheral blood (r = 0.29; p = 0.09).

Conclusions

Malignant disease ranks as the leading cause of EPE. The presence of EPE should not be considered as a predictive factor of benign conditions. Pleural parasitic infestation (PPI) should be emphasized in areas with a high incidence of parasitic disease.

Hodgkin's Lymphoma as an Unusual Cause of Eosinophilic Pleural Effusion

Eosinophilic pleural effusion can be the first presenting feature of a wide range of diseases, with malignancy being the commonest cause. Elevated levels of eosinophils could be an indicator of a favourable prognosis. In clinical practice, malignant lymphomas have been rarely associated with eosinophilic pleural effusions. In this report, we present the case of a 37-year-old otherwise healthy woman, who initially presented with a cough of five months' duration. Diagnostic workups including pleural and lymph node biopsies confirmed the diagnosis of nodular lymphocyte-predominant Hodgkin’s lymphoma. 

Interleukin-5-producing malignant pleural mesothelioma with eosinophilic pleural effusion

Malignant tumors are often associated with eosinophilic pleural effusion. Here, we encountered a case of interleukin‐5 (IL‐5)‐producing malignant pleural mesothelioma with eosinophilic pleural effusion. The patient was a 50‐year‐old male. He had a history of a cough for several weeks and had visited a local doctor. Left pleural effusion was noted, and the patient was referred to our hospital. He was diagnosed with malignant pleural mesothelioma by pleural biopsy, with eosinophilic pleural effusion. IL‐5 in the pleural effusion increased, and tumor cells were IL‐5‐positive by immunostaining. There have been few reports of IL‐5‐producing tumors, and this is the first report of IL‐5‐producing malignant pleural mesothelioma. Host‐tumor cell interactions cause eosinophilic pleural effusion. In patients with eosinophilic pleural effusion, malignant pleural effusion should be considered. It is necessary to clarify the pathophysiology of malignant tumors and eosinophils.

Diagnostic procedure for idiopathic eosinophilic pleural effusion: a single-center experience

Background

Eosinophilic pleural effusion (EPE) is attributed to several well-recognised causes. However, some patients remain idiopathic, even after thorough clinical work-up. The present study aimed to better characterize idiopathic EPE (IEPE) and to outline the diagnostic procedure for this disease.

Methods

Complete clinical data of 11 consecutive patients with IEPE were prospectively collected and analysed. Preliminary diagnostic procedure of IEPE in our hospital was performed.

Results

All the 11 patients had respiratory symptoms and unilateral pleural effusion (PE) occurred in 4 patients. The mean percentage of eosinophils in PE was 22.4% (range, 12.4–50.5%). Lactate dehydrogenase, adenosine deaminase, proteins and carcinoembryonic antigen in PE were 246.0 U/L (range, 89.8–421.9 U/L), 13.8 U/L (range, 1.8–24.0 U/L), 42.6 g/dl (range, 32.8–52.6 g/dl) and 2.17 mg/mL (range, 0.46–4.31 mg/mL), respectively. Parasite-specific IgG antibody in blood and parasite eggs in stool were both negative. No evidence of tuberculosis or malignancy was observed in pleural biopsy. Symptoms and abnormal pulmonary imaging were eliminated after glucocorticoid use.

Conclusions

IEPE is a diagnosis of exclusion. Patients with EPE without a clear cause should be asked to provided complete medical, surgical and drug-related histories. A thorough work-up is essential. Moreover, we recommend follow-up after the use of glucocorticoid until effusion resolves.

Trial registration

GYFYY. Registration No: GYFYY20150901221. Registered time: 1 September 2015. Date of enrolment of the first participant to the trial: 22 January 2016.

Lactate determination in pleural and abdominal effusions: a quick diagnostic marker of exudate-a pilot study

Pleural or abdominal effusions are frequent findings in ICU and Internal Medicine patients. Diagnostic gold standard to distinguish between transudate and exudate is represented by "Light's Criteria," but, unfortunately, the chemical-physical examination for their calculation is not a rapid test. Pursuing an acid-base assessment of the fluid by a blood-gas analyzer, an increase of lactate beyond the normal serum range is reported in the exudative effusions. The advantages of this test are that it is a very fast bed-side test, executable directly by the physician. The aim of this study is to evaluate whether the increase in lactate in pleural and abdominal effusions might be used as a criterion for the differential diagnosis of the nature of the fluid. Sixty-nine patients with pleural or abdominal effusions and clinical indication for thoracentesis or paracentesis were enrolled. Acid-base assessment with lactate, total protein, and LDH dosage on the serum, and acid-base assessment with lactate, total protein, and LDH dosage, cytology, and bacterial culture on the fluid were performed to each patient. Fluid-blood lactate difference (ΔLacFB) and fluid-blood lactate ratio (LacFB ratio) were calculated. A statistical analysis was carried out for fluid lactate (LacF), ΔLacFB, and LacFB ratio, performing ROC curves to find the cut-off values with best sensitivity (Sn) and specificity (Sp) predicting an exudate diagnosis: LacF: cut-off value: 2.4 mmol/L; AU-ROC 0.854 95% CI 0.756-0.952; Sn 0.77; Sp 0.84. ΔLacFB: cut-off value: 0.95 mmol/L; Au-ROC 0.876 95% CI 0.785-0.966; Sn 0.80; Sp 0.92. LacFB ratio: cut-off value: 2 mmol/L; Au-ROC 0.730 95% CI 0.609-0.851; Sn 0.74; Sp 0.65. Lactate dosage by blood-gas analyzer on pleural and abdominal effusions seems to be a promising tool to predict a diagnosis of exudate.

Pirfenidone-induced Eosinophilic Pleurisy

The patient was a 69-year-old man with idiopathic pulmonary fibrosis who was taking pirfenidone. After 7 weeks of treatment, he suffered from left-sided eosinophilic pleurisy. Medical thoracoscopy was performed and the histopathological examination of the parietal pleura revealed the massive infiltration of eosinophils and lymphoid follicles. After stopping pirfenidone therapy, the patient's pleural effusion disappeared without additional treatment, and never recurred. This is the first case report of pirfenidone-induced pleurisy.

Eosinophilia in Pulmonary Disorders

Lung disease associated with marked peripheral blood eosinophilia is unusual and nearly always clinically significant. Once recognized, it is generally easy to manage, albeit with long-term systemic corticosteroids. A failure to respond to oral steroids in the context of good compliance suggests a malignant cause for the eosinophilia. An important development is the introduction of antieosinophil therapies, particularly those directed against the interleukin 5 pathway, which is hoped to provide benefit in the full spectrum of eosinophilic lung disease as well as asthma, reducing the burden of side effects and resultant comorbidities.

Pleuroscopy in 'Idiopathic' eosinophilic pleural effusions

BACKGROUND

Idiopathic eosinophilic pleural effusions (IEPEs) comprise the eosinophilic pleural effusions for which a specific aetiology cannot be established. There are no reports investigating IEPE on the basis of a systematically applied pleuroscopy approach and entailing an appropriate patient follow-up till the final outcome is established; existing series rather combine clinical and thoracocentesis criteria to establish the idiopathic character of the diagnosis.

OBJECTIVES

The aim of our study was to assess the clinical outcome of patients with IEPE, who underwent a systematic diagnostic approach by pleuroscopy.

METHODS

We studied 10 patients with IEPE among 175 consecutive patients who underwent pleuroscopy for undiagnosed pleural effusion. Pleural biopsies were obtained from observed lesions. All patients were followed up by means of clinical examination and imaging.

RESULTS

The diagnosis of IEPE was established in 10 patients (median age was 50.5 years, range 35-91). Macroscopic examination of the pleura showed diffuse thickening with pleural plaques in eight patients, consistent with diffuse pleural eosinophilic inflammation histologically proven. In two patients, macroscopic examination showed scattered nodules associated with non-caseating granulomas histologically. In all 10 patients, a specific aetiology could not be established. Follow-up was available for all patients ranging from 24-102 months (median 60 months). No patient received a specific treatment during the follow-up period. No relapse of a pleural effusion was documented during this period.

CONCLUSION

Pleuroscopy is mandatory in diagnosing IEPE. Negative histology and a long follow-up showed a benign course. These findings suggest that we should call these effusions 'indeterminate'.

Tuberculous pleural effusion

Tuberculous pleural effusion (TBPE) is the most common form of extrapulmonary tuberculosis (TB) in Spain, and is one of the most frequent causes of pleural effusion. Although the incidence has steadily declined (4.8 cases/100,000population in 2009), the percentage of TBPE remains steady with respect to the total number of TB cases (14.3%-19.3%). Almost two thirds are men, more than 60% are aged between 15-44years, and it is more common in patients with human immunodeficiency virus. The pathogenesis is usually a delayed hypersensitivity reaction. Symptoms vary depending on the population (more acute in young people and more prolonged in the elderly). The effusion is almost invariably a unilateral exudate (according to Light's criteria), more often on the right side, and the tuberculin test is negative in one third of cases. There are limitations in making a definitive diagnosis, so various pleural fluid biomarkers have been used for this. The combination of adenosine deaminase and lymphocyte percentage may be useful in this respect. Treatment is the same as for any TB. The addition of corticosteroids is not advisable, and chest drainage could help to improve symptoms more rapidly in large effusions.

Pleural effusion: diagnosis, treatment, and management

A pleural effusion is an excessive accumulation of fluid in the pleural space. It can pose a diagnostic dilemma to the treating physician because it may be related to disorders of the lung or pleura, or to a systemic disorder. Patients most commonly present with dyspnea, initially on exertion, predominantly dry cough, and pleuritic chest pain. To treat pleural effusion appropriately, it is important to determine its etiology. However, the etiology of pleural effusion remains unclear in nearly 20% of cases. Thoracocentesis should be performed for new and unexplained pleural effusions. Laboratory testing helps to distinguish pleural fluid transudate from an exudate. The diagnostic evaluation of pleural effusion includes chemical and microbiological studies, as well as cytological analysis, which can provide further information about the etiology of the disease process. Immunohistochemistry provides increased diagnostic accuracy. Transudative effusions are usually managed by treating the underlying medical disorder. However, a large, refractory pleural effusion, whether a transudate or exudate, must be drained to provide symptomatic relief. Management of exudative effusion depends on the underlying etiology of the effusion. Malignant effusions are usually drained to palliate symptoms and may require pleurodesis to prevent recurrence. Pleural biopsy is recommended for evaluation and exclusion of various etiologies, such as tuberculosis or malignant disease. Percutaneous closed pleural biopsy is easiest to perform, the least expensive, with minimal complications, and should be used routinely. Empyemas need to be treated with appropriate antibiotics and intercostal drainage. Surgery may be needed in selected cases where drainage procedure fails to produce improvement or to restore lung function and for closure of bronchopleural fistula.

Getting the most from pleural fluid analysis

Virtually, every pulmonary disease and most non-pulmonary diseases may be associated with a pleural effusion. The presence of a pleural effusion allows the clinician to 'diagnose' or narrow the differential diagnosis and aetiology of the fluid collection. However, pleural fluid analysis (PFA) in isolation rarely provides a definitive diagnosis. This review discusses the rationale for evaluating patients with a pleural effusion. If the clinician obtains a detailed history, performs a comprehensive physical examination, reviews pertinent blood tests, and evaluates the chest imaging findings prior to thoracentesis, there should be a high likelihood of establishing a firm clinical diagnosis based on the appropriate PFA. This manuscript reviews the clinical presentation, chest imaging findings, duration and natural course of specific pleural effusions to help narrow the range of pre-thoracentesis diagnoses. A diagnosis of transudative effusion confirms an imbalance in hydrostatic and oncotic pressures, normal pleura and a limited differential diagnosis, which is typically apparent from the clinical presentation. Exudates are the result of infections, malignancies, inflammation, impaired lymphatic drainage or the effects of drugs, and pose a greater diagnostic challenge. The differential diagnosis for a pleural exudate can be narrowed if LDH levels exceed 1000 IU/L, the proportion of lymphocytes is ≥80%, pleural fluid pH is <7.30 or there is pleural eosinophilia of >10%.

É possível diferenciar derrames pleurais linfocíticos secundários a tuberculose ou linfoma através de variáveis clínicas e laboratoriais?

OBJETIVO: Descrever características clínicas e laboratoriais em pacientes com derrames pleurais linfocíticos secundários a tuberculose ou linfoma, a fim de identificar as variáveis que possam contribuir no diagnóstico diferencial dessas doenças. MÉTODOS: Estudo retrospectivo com 159 pacientes adultos HIV negativos com derrame pleural linfocítico secundário a tuberculose ou linfoma (130 e 29 pacientes, respectivamente) tratados no Ambulatório da Pleura, Instituto do Coração, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo (SP), entre outubro de 2008 e março de 2010. RESULTADOS: A média de idade e de duração dos sintomas foi menor no grupo tuberculose que no grupo linfoma. Os níveis pleurais de proteínas, albumina, colesterol, amilase e adenosina desaminase (ADA), assim como os níveis séricos de proteínas, albumina e amilase, foram maiores no grupo tuberculose, enquanto os níveis séricos de colesterol e triglicérides foram maiores no grupo linfoma. As contagens de leucócitos e linfócitos no líquido pleural foram maiores no grupo tuberculose. Células malignas estavam ausentes no grupo tuberculose, entretanto, linfócitos atípicos foram observados em 4 desses pacientes. No grupo linfoma, a citologia para células neoplásicas foi positiva, suspeita e negativa em 51,8%, 24,1% e 24,1% dos pacientes, respectivamente. A imunofenotipagem do líquido pleural foi conclusiva na maioria dos pacientes com linfoma. CONCLUSÕES: Nossos resultados demonstram semelhanças clínicas e laboratoriais entre os pacientes com tuberculose ou linfoma. Embora os níveis de proteínas e ADA no líquido pleural tendam a ser mais elevados no grupo tuberculose que no grupo linfoma, mesmo essas variáveis mostraram uma sobreposição. Entretanto, nenhum paciente com tuberculose apresentou níveis de ADA no líquido pleural inferiores ao ponto de corte (40 U/L).

The prevalence and diagnostic significance of eosinophilic pleural effusions: a meta-analysis and systematic review

BACKGROUND

Eosinophilic pleural effusion (EPE) is defined by an eosinophil count of ≥10% in the pleural fluid and often caused by air or blood in the pleural space. The diagnostic significance of EPEs is still a matter of debate.

OBJECTIVE

The objective of this study was to systematically review the medical literature to evaluate the diagnostic significance of EPEs.

METHODS

Electronic databases were searched from 1950 to April 2010 to perform a meta-analysis. Data were extracted using standardized forms, and pooled odds ratios with 95% confidence intervals were calculated. A logistic regression analysis was also performed to evaluate the association between the pleural eosinophil counts and the likelihood of underlying causes of EPEs.

RESULTS

We identified a total of 687 cases of EPE. The most common cause of EPEs was malignancy (26%) followed by idiopathic (25%) and parapneumonic (13%) effusions. The likelihood of malignancy or tuberculosis was somehow lower in EPEs than in non-EPEs, but the differences were not statistically significant. The prevalence of malignancy was significantly lower in the group of patients that required a pathologic confirmation (21 vs. 30%; p = 0.01). The likelihood of malignancy was inversely correlated with the pleural fluid eosinophil counts. The likelihood of idiopathic effusion was significantly higher in EPEs than in non-EPEs.

CONCLUSIONS

Malignancy was the most common cause of EPEs. EPEs appeared to be a negative predictor of malignancy when a pleural fluid eosinophil count was extremely high. EPEs were more likely to be idiopathic as compared with non-EPEs.

Warfarin-induced eosinophilic pleural effusion

A 29-year-old man suffering from dyspnea and eosinophilic pleural effusion after being on warfarin for pulmonary thromboembolism for a period of one month, was readmitted to our hospital. Etiology of pleural effusion other than warfarin was excluded. To the best of our knowledge, this is the first case of warfarin-induced pleural effusion reported in Korea.

Host-derived interleukin-5 promotes adenocarcinoma-induced malignant pleural effusion

RATIONALE

IL-5 is a T helper 2 cytokine important in the trafficking and survival of eosinophils. Because eosinophils can be found in malignant pleural effusions (MPE) from mice and humans, we asked whether IL-5 is involved in the pathogenesis of MPE.

OBJECTIVES

To determine the role of IL-5 in MPE formation.

METHODS

The effects of IL-5 on experimental MPE induced in C57BL/6 mice by intrapleural injection of syngeneic lung (Lewis lung cancer [LLC]) or colon (MC38) adenocarcinoma cells were determined using wild-type (il5(+/+)) and IL-5-deficient (il5⁻(/)⁻) mice, exogenous administration of recombinant mouse (rm) IL-5, and in vivo antibody-mediated neutralization of endogenous IL-5. The direct effects of rmIL-5 on LLC cell proliferation and gene expression in vitro were determined by substrate reduction and microarray.

MEASUREMENTS AND MAIN RESULTS

Eosinophils and IL-5 were present in human and mouse MPE, but the cytokine was not detected in mouse (LLC) or human (A549) lung and mouse colon (MC38) adenocarcinoma-conditioned medium, suggesting production by host cells in MPE. Compared with il5(+/+) mice, il5⁻(/)⁻ mice showed markedly diminished MPE formation in response to both LLC and MC38 cells. Exogenous IL-5 promoted MPE formation in il5(+/+) and il5⁻(/)⁻ mice, whereas anti-IL-5 antibody treatment limited experimental MPE in il5(+/+) mice. Exogenous IL-5 had no effects on LLC cell proliferation and gene expression; however, IL-5 was found to be responsible for recruitment of eosinophils and tumor-promoting myeloid suppressor cells to MPE in vivo.

CONCLUSIONS

Host-derived IL-5 promotes experimental MPE and may be involved in the pathogenesis of human MPE.

[Eosinophilic pleural effusion associated to Churg and Strauss syndrome]

Eosinophilic pleural effusion (EPE) is defined as pleural eosinophilia greater than 10%. EPE can be seen in almost all conditions that can cause pleural effusion, but some aetiologies have to be investigated due to their frequency or potential severity. The most common aetiology of EPE is the presence of air or blood in the pleural cavity. Other frequent aetiologies include bacterial pneumonia, tuberculosis, parasitic disease and certain drugs. Although often considered to be a sign of a benign condition, pleural eosinophilia may be associated with malignancies. EPE may also indicate the presence of Churg and Strauss syndrome. We report the case of a 27-year-old man, in whom the exploration of EPE led to the diagnosis of Churg and Strauss syndrome with the association of asthma, blood and alveolar eosinophilia, myopericarditis and positive antineutrophil cytoplasmic antibodies (ANCA). This case report enables us to discuss the different causes of EPE and to illustrate how it may be a manifestation of Churg and Strauss syndrome.

Recent advances in the diagnosis and management of malignant pleural effusions

Malignant pleural effusions (MPEs) are an important complication for patients with intrathoracic and extrathoracic malignancies. Median survival after diagnosis of an MPE is 4 months. Patients can present with an MPE as a complication of far-advanced cancer or as the initial manifestation of an underlying malignancy. Common cancer types causing MPEs include lymphomas, mesotheliomas, and carcinomas of the breast, lung, gastrointestinal tract, and ovaries. However, almost all tumor types have been reported to cause MPEs. New imaging modalities assist the evaluation of patients with a suspected MPE; however, positive cytologic or tissue confirmation of malignant cells is necessary to establish a diagnosis. Even in the presence of known malignancy, up to 50% of pleural effusions are benign, underscoring the importance of a firm diagnosis to guide therapy. Rapidly evolving interventional and histopathologic techniques have improved the diagnostic yield of standard cytology and biopsy. Management of an MPE remains palliative; it is critical that the appropriate management approach is chosen on the basis of available expertise and the patient's clinical status. This review summarizes the pathogenesis, diagnosis, and management of MPE. Studies in the English language were identified by searching the MEDLINE database (1980-2007) using the search terms pleura, pleural, malignant, pleurodesis, and thoracoscopy.

Pulmonary paragonimiasis with coincidental malignant mesothelioma

A 72-year-old man patient was referred to our institution for evaluation and treatment of right pleural effusion. Eosinophilic pleural effusion and peripheral eosinophilia were identified during the course of hospitalization. Pulmonary paragonimiasis was confirmed by the presence of paragonimus-specific IgG antibodies for Paragonimus (P.) westermani and P. miyazakii in his serum. Although Praziquantel, a highly effective agent for the treatment of lung flukes was repeatedly administered, the pleural effusion did not subside and the patient's condition gradually deteriorated until his death due to circulatory insufficiency. Postmortem examination revealed malignant mesothelioma of the sarcomatous type encasing the right lung and heart. Cardiac involvement accompanied with old and recent-onset myocardial ischemic changes resulted in death of this patient. Here, we report a very rare case of malignant mesothelioma with a concomitant infection of parasitic lung fluke.

Hydatid cyst presenting as an eosinophilic pleural effusion

A 61-year-old woman presented with an eosinophilic pleural effusion, secondary to transdiaphragmatic intrapleural spread of an hepatic hydatid cyst. Right posterolateral thoracotomy and frenotomy revealed a loculated pleural effusion associated with a 10 x 8 cm hydatid cyst in the posterior segment of the liver. Hydatid disease should be included in the differential diagnosis of eosinophilic pleural effusions in endemic regions.

Diltiazem-induced eosinophilic pleural effusion

A 68-year-old woman developed eosinophilic pleural effusion and systemic eosinophilia 2 months after starting antihypertensive therapy with diltiazem. Several drugs are known to cause this disorder; however, the only other drug the patient had been taking was clonidine, which she had taken for the past 3-4 years. She was evaluated for all other possible causes of eosinophilia and eosinophilic pleural effusion, including malignancy, infection, and autoimmune disorders. Her symptoms resolved after diltiazem was discontinued, and no recurrence was noted on follow-up. To our knowledge, this is the first case report of eosinophilic pleural effusion caused by diltiazem. According to the Naranjo adverse drug reaction probability scale, a probable relationship existed between diltiazem and the patient's eosinophilia and pleural effusion. Although numerous drugs have been associated with eosinophilia and eosinophilic pleural effusion, the spectrum may actually be wider than is commonly thought and may include such unrecognized agents as diltiazem.

Eosinophilic pleural effusion as the first presentation of angioimmunoblastic T cell lymphoma

Eosinophilic pleural effusion (EPE), defined as pleural effusion that contains at least 10% eosinophils among the leukocytes, can be a manifestation of a great variety of diseases. However, eosinophilia is a relatively rare finding in malignant pleural effusions, and it has been used as an indicator of good prognosis. In clinical experience, very few cases of malignant lymphomas accompanied by EPE have been reported. In this report, we present an 82-year-old otherwise healthy man with the initial presentation of left EPE. Pleural biopsy could not yield a definite diagnosis initially. Hookworm ova were also found in the stool and parasite associated with EPE was suspected. However, after anti-parasitic agent treatment with mebendazole, the pleural effusion did not improve. Six months later, bilateral neck, axillary and inguinal lymphadenopathy developed, and lymph node biopsy confirmed the diagnosis of angioimmunoblastic T cell lymphoma, with positive CD10 expression. Therefore, we retrospectively carried out CD10 staining of the sample obtained from pleural biopsy and the positive result confirmed that the etiology of EPE was due to malignant T cell lymphoma. The patient refused chemotherapy and he died 1 month later.

Propylthiouracil-Associated Eosinophilic Pleural Effusion: A Case Report

We describe an unusual case of a patient with eosinophilic pleural effusion (EPE) associated with long-term propylthiouracil (PTU) administration. A 43-year-old woman was admitted to our hospital after complaining of chest pain. She had had Graves' disease, which had been treated with PTU for 11 years. Right-sided pleural effusion was detected and the result of thoracentesis confirmed an EPE. The patient's detailed medical evaluation failed to reveal any other cause of EPE. PTU was terminated since it was thought to be the cause. Despite withdrawal of the medication, however, the pleural effusion persisted for 6 weeks, and steroid therapy was planned for 15 days in decreasing dosages. During the control visit 10 days after the initiation of steroid therapy, no pleural effusion was observed, and the steroid was discontinued. Rechallenge with PTU produced recurrent pleural effusion. Therapy with PTU was again terminated, and treatment with methimazole and a brief course of low-dose corticosteroids were begun. Chest radiography revealed disappearance of the effusion within 10 days and it did not recur during a 1-year follow-up. To our knowledge, there is only 1 other case in the English-language literature describing EPE caused by PTU. Our report is of particular importance because it describes the development of that disorder in the 11th year of PTU treatment. It also shows that steroid therapy can be effective in treating drug-induced EPE.

Il versamento pleurico: aspetti eziologici, diagnostici e clinici

Il coinvolgimento della pleura puÒ comparire nel corso di molteplici e differenti patologie. Le cause che sottendono un versamento pleurico possono essere intra-toraciche o sistemiche e, se in alcuni casi queste appaiono facilmente individuabili grazie a segni clinici patognomonici, in altri casi l’inquadramento nosografico di un versamento puÒ risultare complesso, dovendosi basare su elementi clinici e reperti laboratoristico-strumentali spesso aspecifici.

Eosinophilic Pleural Effusion due to Cloxacillin and Piperacillin/Tazobactum

A young male was treated for right-sided pneumonia with cloxacillin and piperacillin/tazobactam. As he was recovering from the pneumonia he developed left-sided pleuritic pain and pleural effusion. At thoracocentesis an exudative pleural effusion contained 16% eosinophils with a simultaneous 28% peripheral eosinophilia. An allergic reaction to penicllins was thought to be the cause. After withdrawal of those medications and institution of pred-nisolone a rapid resolution was seen of symptoms, signs, peripheral eosinophilia and radiological abnormalities.

Using urea dilution to standardise components of pleural and bronchoalveolar lavage fluids in the dog

AIM

To develop a technique to estimate the volume of epithelial lining fluid (ELF) obtained during bronchoalveolar lavage (BAL) and pleural lavage (PL) in the dog, using the urea dilution method.

METHODS

BAL and PL fluids were obtained by saline lavage of pulmonary and pleural cavities of nine clinically healthy mixed-breed dogs immediately after euthanasia. Cell counts in the BAL and PL fluids were measured using standard techniques. The concentration of ELF in each lavage fluid was calculated from the relative concentration of urea in plasma and in each type of lavage fluid. Cell counts in ELF were then calculated.

RESULTS

There were substantially higher cell counts in ELF compared to BAL or PF fluid. However, nucleated cell counts in ELF could not be predicted from cell counts in BAL or PL fluid.

CONCLUSIONS AND CLINICAL RELEVANCE

These results suggest that accurate assessment of cellular or non-cellular components in lavage fluids should include a calculation of the proportion of ELF recovered, using a method such as urea dilution.

Eosinophilic pleural effusion, peripheral eosinophilia, pleural thickening, and hepatosplenomegaly in sarcoidosis

In this atypical case of sarcoidosis with an unusual combination of clinical and laboratory findings, a 32-year-old male presented with a 3-month history of thoracic pain complicated with dyspnea. Laboratory tests, chest radiography, and CT scans of the chest and abdomen revealed eosinophilia of pleural effusion and blood, pleural thickening, hepatosplenomegaly, and bronchiolitis obliterans. In cases such as this, in which pleural fluid eosinophilia is accompanied by peripheral eosinophilia and splenohepatomegaly, underlying malignancies such as Hodgkin lymphoma should be ruled out. A biopsy of the mediastinal lymph nodes suggested noncaseating epithelioid granulomas, characteristic of sarcoidosis. The patient underwent prednisolone therapy for 1 year and is doing well 2 years after initial diagnosis.

Using urea dilution to standardise cellular and non-cellular components of pleural and bronchoalveolar lavage (BAL) fluids in the cat

A technique to standardise the analysis of cellular and non-cellular components in epithelial lining fluid (ELF) collected during saline lavage of pulmonary and pleural cavities was developed using the urea dilution method. Bronchoalveolar lavage (BAL) and pleural lavage (PL) fluids were collected from 12 clinically healthy cats. Total and differential cell counts in BAL fluid were within normal ranges for the cat, while cell counts in PL fluid were assumed to be normal based on clinical health during examination, auscultation and lactate dehydrogenase (LDH) activities being comparable with other species. The major clinical implication of this study was that nucleated cell counts within feline ELF could not be predicted from analysis of lavage fluid which suggests that calculation of the proportion of ELF in lavage fluid by the urea dilution method may be necessary to avoid misdiagnosis of health or disease in pulmonary or pleural cavities.

Early delayed-type hypersensitivity eosinophil infiltrates depend on T helper 2 cytokines and interferon-gamma via CXCR3 chemokines

We investigated the role of T helper (Th)1- and Th2-type cytokines in delayed-type hypersensitivity to soluble protein antigens elicited early postimmunization. Mice were sensitized by intradermal injection without adjuvants, or subcutaneously with complete Freund's adjuvant, and subsequently ear challenged intradermally. As soon as day 3, antigen-specific eosinophil-rich responses were elicited in wild-type mice, but not in T-cell receptor-alpha-/- mice without adjuvant. Draining lymph node T cells stimulated with antigen secreted interleukin (IL)-4, IL-5 and interferon-gamma (IFN-gamma). IFN-gamma-dependent specific immunoglobulin G (IgG)2a and IL-4-dependent IgG1 were also generated. Delayed-type hypersensitivity ear swelling and local eosinophil recruitment were decreased in IL-5-/-, IL-4-/- and signal transducer and activator of transcription-6 (STAT-6)-/- mice, and with anti-IL-4 treatment of wild-type mice, suggesting Th2 mechanisms. Interestingly, responses were also decreased in IFN-gamma-/- mice, and IFN-gamma protein and the IFN-gamma-inducible CXC chemokine, IP-10, were present in 24-hr ear tissue extracts, suggesting Th1 effects. Finally, ear swelling, total histology and eosinophils were decreased in mice deficient in CXCR3, the chemokine receptor for IP-10. These results suggest that both a Th2-like (IL-5, IL-4 and STAT-6) and a Th1-like (IFN-gamma, IP-10, CXCR3) pathway contribute to eosinophil recruitment in early delayed-type hypersensitivity.

Valproic Acid-induced Eosinophilic Pleural Effusion

Valproic acid is a carboxylic acid used for the treatment of both seizure and mood disorders. Its association with pleural fluid eosinophilia has been reported once in the English language literature. We present another case of valproic acid-induced pleural fluid eosinophilia associated with fever and peripheral blood eosinophilia. Extensive evaluation failed to reveal any other cause of eosinophilic pleural effusion, and the effusion resolved with discontinuance of valproic acid. Rechallenge with valproic acid produced recurrent symptoms. Valproic acid should be considered a possible cause of eosinophilic pleural effusion.

Eosinophilia and progression to active tuberculosis in HIV-1-infected Ugandans

It has been suggested that type 1 immune responses protect against tuberculosis (TB), while type 2 responses, such as those induced by helminths, may suppress protective responses and increase susceptibility to TB. Factors associated with progression to active TB were investigated in a cohort of HIV-1-infected Ugandan adults, a group at high risk of TB. High rates of subsequent progression to active TB were associated with eosinophil counts > or = 0.4 x 10(9)/L at enrolment. Eosinophilia at enrolment was associated with male gender, low socio-economic status, high CD4+ T cell counts, and schistosomiasis, but adjusting for these factors did not explain the association of eosinophilia with progression to active TB (adjusted rate ratio = 2.76, P = 0.004). Eosinophilia is most likely to be indicative of a type 2 immune response induced by helminth infection in this Ugandan cohort, but the mechanism of the observed association between eosinophilia and risk of TB remains to be determined.