Pleural Fluid Specimens Research Articles

Rapid immunodiagnosis of tuberculosis in a woman receiving anti-TNF therapy

A 63-year-old German woman with a 24-year history of Crohn's disease and associated polyarthralgias presented with severe malaise, dyspnea, fever, night sweats, dry cough and an extensive right-sided pleural effusion. The patient had begun treatment with bi-weekly subcutaneous injections of adalimumab 5 weeks earlier. Physical examination, chest X-ray, transthoracic ultrasonography, pleural tap and drainage, bacterial and cytological analyses of pleural fluid, bronchoscopy, microscopy and bacteriological culture of pleural exudates and bronchoalveolar lavage fluid, thoracic CT, thoracoscopy, histopathology of pleural biopsy, tuberculin skin test, nucleic acid amplification of mycobacterial RNA and DNA in the pleural fluid specimens and the parietal pleural biopsy, microscopy of sputum samples, ESAT-6-specific and CFP-10-specific interferon-gamma enzyme-linked immunospot assay on peripheral blood and pleural exudate mononuclear cells. Pulmonary and pleural tuberculosis. Cessation of adalimumab treatment. Initiation of quadruple antibiotic therapy with isoniazid, rifampin, ethambutol and pyrazinamide. Prednisolone administered to reduce the pleural effusion.

Contribution of a Pleural Antigen Assay (Binax NOW) to the Diagnosis of Pneumococcal Pneumonia

To determine whether the detection of pneumococcal antigen in pleural fluid augments conventional microbiological methods used for the etiologic diagnosis of pneumonia. In this retrospective study, a rapid immunochromatographic test (ICT) [NOW Streptococcus pneumoniae assay; Binax; Scarborough, ME] was performed on pleural fluid samples from 34 patients with pneumonia due to S pneumoniae, 89 patients with effusions of nonpneumococcal origin, and 17 patients with pneumonia of unknown etiology. Data on blood cultures, pleural fluid cultures, and urinary antigen tests were recorded. The ICT test result was positive in 24 of 34 patients (70.6%) with pneumococcal pneumonia and negative in 83 of 89 patients (93.3%) without pneumococcal pneumonia. The sensitivity of the pleural ICT test was higher than that obtained for blood (37.5%) and pleural fluid cultures (32.3%), but lower than the detection of pneumococcal antigen in urine samples (82.1%). However, three patients with pneumococcal pneumonia and a negative ICT urine test result had a positive pleural fluid antigen detection result test. Previous antibiotic exposure did not influence pneumococcal antigen detection in either pleural fluid or urine specimens. Six additional patients with empyema due to anaerobes (three patients), Streptococcus viridans (two patients), and Enterococcus faecalis (one patient) had false-positive pleural ICT test results. Finally, the ICT assay finding was also positive in 5 of 17 patients (29.4%) with pneumonia without a definite microbiological cause. The ICT test performed on pleural fluid samples augments the standard diagnostic methods of blood and pleural fluid cultures, even in the case of prior antibiotic therapy, and enhances the ICT urinary antigen assay.

Clinical Utility of Polymerase Chain Reaction for Diagnosis of Smear-negative Pleural Tuberculosis

Polymerase chain reaction (PCR) is a molecular biology technique which can detect Mycobacterium tuberculosis (TB) genome in pleural fluid; however, the results are variable. Two hundred and twelve pleural fluid specimens suspected to be possibly associated with tuberculosis with negative acid-fast smears were sent to our laboratory to test for the presence of M. tuberculosis DNA using nested PCR, the target for the amplification being a segment of IS6110 in the genome of M. tuberculosis. The final diagnosis of TB pleurisy was based on combining clinical judgment with radiologic findings, microbiologic tests, and the histopathologic findings. Forty-nine patients were excluded due to incomplete or inconsistent clinical information. Of 163 patients enrolled, PCR was positive in 23 (43.4%) of 53 patients with TB pleurisy and 5 (4.5%) of 110 patients with non-TB pleurisy, with a sensitivity and specificity of 43.4% and 95.5%, respectively. Positive culture of pleural fluid was found in 15 (28.3%) of the TB pleurisy group and none in the non-TB group. Fifteen (55.6%) of 27 with pleural biopsy demonstrated chronic granulomatous inflammation with or without caseous necrosis. Of these 27 patients, PCR was positive in 12 (44.4%). A higher proportion (70.4%) of patients with TB pleurisy was diagnosed when PCR was combined with biopsy results. These data indicate that PCR alone has limited value in diagnosis of TB pleurisy with negative smear. However, when used in combination with pleural biopsy, it can be used to increase early detection of TB pleurisy in such patients.

Diagnostic accuracy of human telomerase reverse transcriptase mRNA in malignant pleural effusions: A preliminary report for in situ hybridization detection

Background Detection of human telomerase reverse transcriptase (hTERT) mRNA by in situ hybridization (ISH) may be valuable in the diagnosis of cancer. We assessed the diagnostic performance of hTERT mRNA in cells from pleural fluid in malignant pleural effusions (PEs). Methods We used a 2-step ISH with digoxin-labelled oligonucleotide probes to detect hTERT mRNA in a blinded prospective study of cells from 103 unselected pleural fluid specimens. The reference standard for malignant PEs was clinical evaluation and pleural fluid cytology, combined with pleural biopsy, other examination and follow-up as needed. Results According to the final diagnoses, there were 41 malignant PEs, 55 benign PEs and 7 cases with uncertain etiology. When the 7 cryptogenic cases were excluded, the sensitivity and specificity of detectable hTERT mRNA for malignancy were 80% and 95%, respectively. When detection of hTERT mRNA was combined with clinical repeated pleural fluid cytology, the sensitivity and specificity were 90% and 95%, respectively. Conclusions Detection of hTERT mRNA in cells from pleural fluid by ISH could potentially be used in diagnosing malignant PEs as an aid. Further investigations with stricter controls and cross-validation tests will be warranted.

Diagnosis and Treatment of Tuberculous Pleural Effusion in 2006

Tuberculous (TB) pleural effusion occurs in approximately 5% of patients withMycobacterium tuberculosisinfection. The HIV pandemic has been associated with a doubling of the incidence of extrapulmonary TB, which has resulted in increased recognition of TB pleural effusions even in developed nations. Recent studies have provided insights into the immunopathogenesis of pleural TB, including memory T-cell homing and chemokine activation. The definitive diagnosis of TB pleural effusions depends on the demonstration of acid-fast bacilli in the sputum, pleural fluid, or pleural biopsy specimens. The diagnosis can be established in a majority of patients from the clinical features, pleural fluid examination, including cytology, biochemistry, and bacteriology, and pleural biopsy. Measurement of adenosine deaminase and interferon-γ in the pleural fluid and polymerase chain reaction forM tuberculosishas gained wide acceptance in the diagnosis of TB pleural effusions. Although promising, these tests require further evaluation before their routine use can be recommended. The treatment of TB pleural effusions in patients with HIV/AIDS is essentially similar to that in HIV-negative patients. At present, evidence regarding the use of corticosteroids in the treatment of TB pleural effusion is not clear-cut.

Microbiological Diagnosis of Empyema in Children: Comparative Evaluations by Culture, Polymerase Chain Reaction, and Pneumococcal Antigen Detection in Pleural Fluids

Pleural empyema is an increasingly reported complication of pneumonia in children. Microbiological diagnostic tests for empyema by culture frequently have false-negative results due to previous administration of antibiotics. Molecular diagnosis by broad-range 16S ribosomal DNA (rDNA) polymerase chain reaction (PCR) and rapid pneumococcal antigen detection are reliable tools, but their diagnostic value has not been clearly established for pleural fluid samples. Pneumococcal antigen detection has only been validated for urine and cerebrospinal fluid samples. Over 4 years, pleural fluid specimens were collected from 78 children with pleural empyema. Standard culture, pneumococcal antigen detection by latex agglutination (Pastorex; Bio-Rad) and immunochromatographic testing (Binax NOW Streptococcus pneumoniae), and 16S rDNA PCR were performed on these specimens. Pneumococcal identification by 16S rDNA PCR and sequencing was confirmed by pneumolysin PCR. Of the 78 cases of pleural empyema, 60 (77%) were microbiologically documented by culture or 16S rDNA PCR. Of the 40 pneumococcal empyema cases, 17 (43%) were only diagnosed by PCR and 23 with PCR and culture. The sensitivity and specificity of the latex antigen detection (with the use of culture and/or PCR as the test standard) were 90% and 95%, respectively. The immunochromatographic test detected pneumococcal antigens in 3 additional specimens for which latex agglutination results were negative, thereby increasing the sensitivity of antigen detection. Pneumococcal antigen detection in pleural fluid specimens from children provides a rapid and sensitive method of diagnosis of pneumococcal empyema, which can be confirmed by specific pneumolysin PCR when culture results are negative. Broad-range 16S rDNA PCR has value in detecting bacterial agents responsible for culture-negative pleural empyema.

Acute Pneumonia and Empyema Caused by Mycobacterium Intracellulare

Nontuberculous mycobacterial infection is rarely accompanied by pleural involvement. We report a very rare case of M. intracellulare pulmonary disease with pleural empyema. A 56-year-old man was admitted to our hospital because of fever, purulent sputum and pleuritic chest pain. A chest radiograph and CT revealed pneumonic consolidation in the left lower lobe and loculated hydropneumothorax. The sputum smear was positive for acid fast bacilli. The aspirated pleural fluid was grossly purulent and the smear of the pleural effusion was also positive for acid fast bacilli. M. intracellulare was identified by culture and PCR from sputum and pleural fluid specimens. The patient improved with percutaneous tube drainage of the purulent effusion and antibiotic treatment including clarithromycin, rifampicin, ethambutol and streptomycin.

Pharmacokinetic study of pleural fluid penetration of carbapenem antibiotic agents in chemical pleurisy

We investigated pleural fluid penetration of carbapenem antibiotic agents [imipenem (IPM), panipenem (PAPM), meropenem (MEPM), and biapenem (BIPM)] using an experimental rabbit pleuritis model to clarify the usefulness of the carbapenem agents for the treatment of bacterial pleurisy or pyothorax. Serum and pleural fluid specimens were serially collected at 5, 10, 15, 30, 60, 90, 120, 180, 240, 300, and 360 min after antibiotic administration for measurement of antibiotic levels. We investigated each agent alone as well as drug solutions containing each agent and a dehydropeptidase-I-specific inhibitor, cilastatin (CS), to remove the influence of dehydropeptidase-I-related hydrolysis. Groups of animals (n=3) received each carbapenem agent with or without CS. Serum and pleural fluid antibiotic levels were measured by high-performance liquid chromatography (HPLC). Because Cmax is not useful for evaluating the antimicrobial effects of carbapenem antibiotic agents due to their dose-dependent antimicrobial activity, we also investigated the AUC, which is correlated with the total drug levels in vivo. Among the drug solutions containing CS, MEPM/CS had the highest pleural fluid AUC0-360 (1594.8+/-510.3 microg min/ml), and the highest pleural fluid AUC0-360/plasma AUC0-360 ratio (0.79+/-0.04). BIPM/CS had the highest plasma AUC0-360 (3040.1+/-1525.9 microg min/ml). In pleural fluid AUC0-360/plasma AUC0-360 ratio MEPM/CS was significantly higher than those for the remaining agents. In pleural fluid AUC0-360 and plasma AUC0-360 there were no significant differences among these mixed solutions. MEPM had the most favorable pleural fluid penetration. Pleural fluid penetration should be examined in infection models and in clinical trials.

Low Yield of Microbiologic Studies on Pleural Fluid Specimens

It is generally recommended that pleural fluid samples from pleural effusions of unknown cause be cultured for bacteria, mycobacteria, and fungi. However, the utility of this practice has been not been adequately assessed. Retrospective review. Tertiary care, referral medical center. Five hundred twenty-five patients undergoing diagnostic thoracentesis at Mayo Medical Center, Rochester, MN, over a 12-month period from July 1, 2001, to June 30, 2002. None. Among 525 patients undergoing diagnostic thoracenteses, 476 patients (91%) had one or more cultures performed on their pleural fluid specimens. Thirty-nine positive results (3.0% of 1,320 cultures) occurred in 35 of these 476 patients (7.4%). After excluding likely contaminants, true pathogens were identified in only 19 of 1,320 pleural fluid cultures (1.4%) belonging to 15 patients (3.2% of those who had cultures performed on their pleural fluid specimen). These positive results included 2.3% of aerobic bacterial, 1.2% of anaerobic bacterial, 1.4% of fungal, and 0% of mycobacterial cultures. Microbiologic smears performed on these pleural fluid samples included 357 Gram stains, 109 fungal smears (potassium hydroxide), and 232 acid-fast smears with positive yields of 2.5%, 0%, and 0%, respectively. These positive findings represented 1.3% of all smears performed. Of the specimens obtained from outpatient thoracenteses, only one had a true-positive result (0.8%). Only 1.1% (four specimens) of the cultures performed on free-flowing effusions demonstrated true pathogens; three of these four specimens grew fungi. The positive yield of microbiologic smears and cultures on pleural fluid specimens is low, particularly in the outpatient setting and in patients with free-flowing effusions. Microbiologic testing of pleural fluid specimens should be ordered more selectively.

Cultures of Pleural Effusion Specimens: Low Diagnostic Yield

When thoracentesis is performed to determine the cause of pleural effusion, pleural-fluid specimens usually are cultured. This practice has sometimes been recommended in guidelines and textbooks, but how useful is it? In a retrospective analysis, investigators at the Mayo Clinic recently evaluated the diagnostic yield of 1320 pleural-fluid cultures …

Stability of Adenosine Deaminase During Transportation

Measurement of pleural fluid adenosine deaminase (ADA) levels is useful in the differential diagnosis of pleural effusions. However, at ambient temperatures, the levels of this enzyme decline with time. The purpose of the present study was to identify, test, and optimize additives that stabilize ADA, consequently eliminating the need for dry ice or other cold specimen transport media. A preliminary screen of historically proven stabilizing agents for specific proteins demonstrated effectiveness of glycerol for maintenance of pleural fluid ADA levels. Systematic studies for exploitation of the glycerol effect included the following: (1) supplements to the glycerol of promising alternate compounds, (2) long-term stability studies at ambient and elevated temperatures, (3) a field test of an effective mixture as a means for reduction of specimen transport costs, (4) thermal stability studies for optimization of the agents for use at otherwise denaturing temperatures, and (5) inclusion of pleural fluids from patients with a variety of etiologies, including tuberculous pleurisy, in order to gauge the effectiveness of the stabilizing agents on both the high and low molecular weight forms of ADA. A mixture of glycerol and ethylene glycol, each at 5% concentration, maintained pleural fluid ADA levels for at least 21 days at both room temperatures and 37 degrees C. A field test of 32 pleural fluids found that ADA levels in specimens containing this mixture, sent to the laboratory by surface mail at ambient temperatures, were nearly identical to those in aliquots of the same fluids shipped over dry ice. The bias in the measurement was 0.49 IU/L, with a precision of 2.49 IU/L. The correlation coefficient between the two measurements was 0.97. Thermal stability studies found that tuberculous pleural fluids containing 10% glycerol and 0.10 mol/L sodium sulfate maintained constant ADA levels for at least 10 days at 45 degrees C, an otherwise denaturing temperature for nonstabilized specimens. The addition of stabilizing agents to pleural fluid specimens allows the transport of those specimens to distant laboratories at ambient temperatures without a decline in the ADA levels. Employment of those agents will decrease the cost of the test and facilitate its use in second- and third-world countries.

Comparison of the BDProbeTec ET system with the roche COBAS AMPLICOR System for detection of Mycobacterium tuberculosis complex in the respiratory and pleural fluid specimens

The new BDProbeTec ET System (BDET; BD Biosciences, Sparks, MD) was compared with the Roche COBAS AMPLICOR System (CAS) and culture for Mycobacterium tuberculosis (MTB). A total of 253 specimens (152 respiratory and 101 pleural fluid specimens) collected from 240 patients were tested in parallel with the 3 assays. After resolving the discrepancies, the sensitivity, specificity, and positive and negative predictive values of the BDET for detecting MTB was 76.9%, 93.7%, 71.4%, and 95.2% for the respiratory specimens and 88.9%, 92.4%, 53.3%, and 98.8% for the pleural fluid specimens, respectively. The corresponding values of the CAS were 69.2%, 100%, 100%, and 94% for the respiratory specimens and 33.3%, 100%, 100%, and 93.9% for the pleural fluid specimens, respectively. No significant differences in sensitivities were observed between the results of both assays for the respiratory specimens. However, statistically significant differences in sensitivities were found between the BDET and CAS for the pleural fluid specimens ( P = .02). Although the BDET was less specific than the CAS ( P = .007), the BDET has an excellent sensitivity for detecting MTB in the pleural fluid specimens. Considering the low sensitivity of other available tests, the BDET can be a useful diagnostic tool for excluding MTB, particularly in the pleural fluid specimens.

Polymerase Chain Reaction of Pleural Biopsy Is a Rapid and Sensitive Method for the Diagnosis of Tuberculous Pleural Effusion

Tuberculous pleural effusion occurs in 30% of patients with tuberculosis (TB). Rapid diagnosis of a tuberculous pleural effusion would greatly facilitate the management of many patients. Polymerase chain reaction (PCR) has been used to detect Mycobacterium tuberculosis in pleural fluid with highly variable sensitivity. To improve our laboratory diagnosis of tuberculous pleural effusion. We applied PCR to detect DNA specific for M tuberculosis in 33 of the studied pleural biopsy specimens using an IS986-based primer that was specific for mycobacterium complex, and compared it to the results of pleural fluid and biopsy cultures performed on either Lowenstein-Jensen (LJ) medium or BACTEC 12B liquid medium (Becton Dickinson Microbiology Systems; Cockeysville, MD), Ziehl-Neelsen (ZN) staining, and histopathology in 45 patients with pleural effusion. Of the 45 patients with pleural effusion who were studied, 26 patients received diagnoses of tuberculous pleural effusion that had been confirmed by either culture and or histopathology, 10 patients received diagnoses of exudative effusion due to causes other than TB, and 9 patients received diagnoses of transudative effusion. Histopathology of the pleural biopsy specimen had a sensitivity of 53.8%. The sensitivity of the ZN staining of pleural fluid and biopsy specimens was 0.0% and 3.8%, respectively. The sensitivity of the culture on both BACTEC 12B liquid medium and LJ medium was higher in pleural biopsy specimens (92.3%) than in pleural fluid specimens (15.4%; p > 0.001). The improvements of the BACTEC culture system improved and shortened the detection time of M tuberculosis in pleural biopsy specimens. PCR of pleural biopsy specimens had 90% sensitivity and 100% specificity. The positive predictive value and the negative predictive value for pleural biopsy specimen cultures were 100% and 90.5% vs 100% and 86.7% for pleural biopsy specimen PCRs. The overall accuracy of PCR of pleural biopsy was similar to the results of pleural biopsy culture, however, PCR of the pleural biopsy was much faster in reaching diagnosis. PCR of pleural biopsy is a useful method when used in combination with the BACTEC culture system and histopathologic examination of pleural biopsy to reach a rapid diagnosis of tuberculous pleural effusion.

Pleural fluid transforming growth factor-beta1 correlates with pleural fibrosis in experimental empyema.

Transforming growth factor-beta1 (TGF-beta1) is a growth factor that is implicated in fibrosis of many organs. The purpose of this study was to determine the sequential levels of TGF-beta1 in the pleural fluid of rabbits that had undergone empyema induction, as fibrosis of the pleural space develops. Thirty-seven rabbits underwent empyema induction. Rabbits were sacrificed on Days 1, 2, 3, 4, 5, 6, and 8. Pleural fluid and viscera pleura specimens were collected at autopsy. TGF-beta1 levels were measured in pleural fluid using a commercially available ELISA kit, and pathologic specimens were scored for evidence of fibrosis (pleural thickness and number of fibroblasts). The median levels of pleural fluid TGF-beta1 increased from 8,100 pg/ml (Days 1 and 2) to 39,600 pg/ml (Day 8). Pleural fluid TGF-beta1 levels closely correlated with microscopic pleural thickness (r = 0.7, p < 0.001) and number of fibroblasts present in the visceral pleura (r = 0.68, p < 0.001). The first increase in pleural fluid levels of TGF-beta1 (Day 3) occurred before the increase in pleural thickness (Day 4) and before the increase in number of fibroblasts (Day 4). In conclusion, pleural fluid levels of TGF-beta1 rise in experimental empyema as pleural fibrosis develops. The rise in empyemic pleural fluid TGF-beta1 levels correlates with markers of pleural space fibrosis.

Detection of numerical aberrations of chromosomes 7 and 9 in cytologic specimens of pleural malignant mesothelioma.

Accurate diagnosis of malignant mesothelioma (MM) in effusion fluid specimens can be challenging. Previous cytogenetic studies demonstrated that chromosomal aneusomy is commonly associated with MM. The authors attempted to determine whether the detection of numerical chromosomal aberrations in the effusion fluid specimens could be a useful diagnostic adjunct in morphologically inconclusive cases for MM. The authors analyzed 17 cytologic specimens (15 pleural fluids, 2 fine-needle aspirates) of histologically confirmed MM obtained from 16 patients using fluorescent in situ hybridization (FISH) with centromeric chromosome 7 and 9 probes. Seventeen benign pleural effusion fluid specimens containing reactive/benign mesothelial (RM) cells were used as controls. After destaining of Diff-Quik-stained smears, the slides were hybridized using a standard FISH protocol. One hundred cells/probe/case were counted manually. For chromosome 7, polysomy (defined as >/= 3 signals/nucleus in >10% of the cells) was present in 88% and 0% of the MM and the RM cases, respectively. Trisomy (defined as 3 signals/nucleus in > 5% of the cells) was present in 77% and 0% of the MM and the RM cases, respectively. Tetrasomy (defined as 4 signals/nucleus in > 10% of the cells) was present in 29% and 0% of the MM and the RM cases, respectively. The mean values of positive cells showing polysomy 7 and trisomy 7 were markedly different in MM and RM cases (39% vs. 4% and 31% vs. 1%, respectively). The frequency of polysomy 9 and trisomy 9 in MM and RM cases was 69% vs. 13% and 62% vs. 6%, respectively. These results suggest that polysomy of chromosome 7 or 9 is a common finding in MM but uncommon in RM. Therefore, in conjunction with cytomorphologic and clinical suspicion of MM, detection of numerical chromosomal aberrations of chromosome 7 using FISH with routine cytologic smears can be a valuable diagnostic adjunct.

Variations in Pleural Fluid WBC Count and Differential Counts With Different Sample Containers and Different Methods

To compare the results of pleural fluid analysis for WBC counts and differential cell counts as follows: (1) counting performed manually vs that performed by an automated cell counter; (2) cells collected in different types of specimen containers; and (3) cell counts performed at 4 and 24 h postthoracentesis. Twenty-eight pleural fluid samples were each collected in five different containers (ie, ethylenediaminetetraacetic acid (EDTA)-treated glass, citrate-treated glass, heparinized glass, plain glass, and plain plastic tubes). The WBC counts and differential cell counts were obtained manually (on the EDTA tube) and with an automated counter on all tubes within 4 h of collection, and again after 24 h of refrigeration. There was a close correlation between the WBC counts obtained manually and those obtained with the automated counter from the pleural fluid samples collected in the EDTA tubes (r = 0.92). With the automated counter, the pleural fluid WBC counts were similar among the three tubes containing anticoagulants, but the counts obtained from the tubes without anticoagulants were significantly lower. The differential cell counts obtained manually and those obtained with the automated cell counter differed substantially. Although the percentage of lymphocytes was similar, the automated counter was inaccurate in differentiating neutrophils from large monocytes or mesothelial cells. The WBC counts obtained within 4 h of collection and 24 h after collection were virtually identical. The WBC counts obtained manually and with the automated counter from pleural fluid samples in EDTA tubes correlated very closely. The pleural fluid WBC count was lower if the pleural fluids had been collected in tubes without an anticoagulant. Automated WBC counts from pleural fluid specimens were inaccurate, possibly due to difficulty in separating neutrophils from monocyte/mesothelial cells. Refrigerated storage for up to 24 h had no significant effect on the total WBC count or on the WBC count differential regardless of the tube utilized.

Measurement of vitamin D-binding protein in pleural fluids and sera by means of a turbidimetric immunoassay measuring system

Background: Vitamin D-binding protein (DBP) has been recognized as a multifunctional plasma protein that can modulate certain immune and inflammatory responses. There may be differences between the DBP concentrations in pleural fluids from various diseases involving a variety of possible responses in the pleural cavity. Methods: An anti-DBP polyclonal antibody was prepared using commercially available DBP to establish a quantitative measuring system for DBP. With a rabbit antibody, a turbidimetric immunoassay (TIA) was developed for DBP with an automatic analyzer. Using this measuring system, the concentrations of DBP were compared with the protein concentration in pleural fluid and serum specimens from patients with various diseases. Results: The fluid DBP concentrations in transudative ( n=11) and exudative ( n=41) effusions were 71.9±21.2 and 180.7±43.7 mg/l, respectively. Among the exudative effusions, the fluid DBP concentrations in the bacterial ( n=10), tuberculous ( n=13), and malignant ( n=18) effusions were 218.8±37.3, 186.7±26.2, and 155.1±41.3 mg/l, respectively. The DBP fluid/serum ratio and the fluid DBP/protein ratio in bacterial effusions were significantly higher than those in tuberculous ( p<0.005, p<0.05, respectively) and malignant effusions ( p<0.0005, p<0.005, respectively), although no statistically significant differences in the serum DBP/protein ratio between those effusions were found. Conclusions: Using the TIA assay, the DBP concentrations in bacterial pleural effusions were significantly higher than in tuberculous and malignant effusions.

Broad-range bacterial detection and the analysis of unexplained death and critical illness.

Broad-range rDNA polymerase chain reaction (PCR) provides an alternative, cultivation-independent approach for identifying pathogens. In 1995, the Centers for Disease Control and Prevention initiated population-based surveillance for unexplained life-threatening infections (Unexplained Death and Critical Illness Project [UNEX]). To address the causes of UNEX cases, we examined 59 specimens from 46 cases by using broad-range bacterial 16S rDNA PCR and phylogenetic analysis of amplified sequences. Specimens from eight cases yielded sequences from Neisseria meningitidis (cerebrospinal fluid from two patients with meningitis), Streptococcus pneumoniae (cerebrospinal fluid from one patient with meningitis and pleural fluid from two patients with pneumonia), or Stenotrophomonas maltophilia (bone marrow aspirate from one patient with pneumonia). Streptococcus pneumoniae rDNA sequence microheterogeneity was found in one pleural fluid specimen, suggesting the presence of multiple strains. In conclusion, known bacterial pathogens cause some critical illnesses and deaths that fail to be explained with traditional diagnostic methods.

A comparative cytologic study of body fluids and urine specimens processed by simple centrifuge and millipore filter techniques

Cyto-preparation of fluids is as important as cytodiagnosis in providing a good diagnostic service. A total of 134 fluid specimens consisting of 41 urine, 40 pleural fluid and 53 peritoneal fluid were processed by routine sediment smear and Millipore filter technique. The cytological diagnosis was categorized as suspicious, positive and negative for malignancy. Comparison of the two techniques was done with regards to recovery of cells, preservation of cell morphology, cell distribution and smear background. The differences were tested for significance by Chi-square tests. ‘P’ value less than 0.05 was considered significant. P value was significant for the parameters: celluiarity and distribution of cells for all three types of fluid. Significant difference was also observed for the parameter morphology of cells except for pleural fluid specimens. For urine specimens, morphology of cells was well preserved in 29 cases (70.7%) with Millipore filtration as compared to 12 cases (29.7%) with sediment smear technique. How ever p value was not significant (p=0.056). An additional 4 specimens (2.9%) with malignant cells were diagnosed by Millipore preparation. Although sediment smear technique is simple rapid, technical difficulties of Millipore filtration are clearly outweighed by the significant retrieval of well preserved, evenly distributed diagnostic cells. Therefore Millipore filtration can be a better option for cell concentration in fluid specimens as compared to the routine sediment smear technique.

Fine-needle aspiration biopsy of granulocytic sarcoma

Because of morphologic similarities, the differential diagnosis of granulocytic sarcoma (GS) in fine-needle aspiration (FNA) specimens includes non-Hodgkin or Hodgkin lymphoma, extramedullary hematopoiesis, poorly differentiated carcinoma, and infection. Twenty-six FNAs and 1 pleural effusion fluid specimen of GS obtained from 23 patients were reviewed for cytomorphologic features and clinical characteristics. The cases were categorized as blastic, immature, or mature GS based on the population of the cells present on the smears. The patients included 18 men and 5 women (mean age, 54 years). Aspiration sites included subcutaneous or soft tissue (15 cases), lymph nodes (5 cases), bones (3 cases), testis (1 case), ileum (1 case), and liver (1 case). One sample of pleural effusion fluid also was included. Review of the patients' clinical history revealed that GS was secondary to chronic myelogenous leukemia (CML) in 17 patients, was secondary to chronic myelomonocytic leukemia (CMML) in 2 patients, and was secondary to acute myelogenous leukemia in 2 patients. GS preceded the manifestation of CML in one patient and of CMML in another patient. Based on the proportions of cells, morphologic classification was attempted and revealed blastic GS in 8 aspirates and 1 pleural effusion fluid specimen, immature GS in 13 aspirates, and mature GS in 5 aspirates. Twelve of 22 specimens from extranodal sites (55%) demonstrated lymphoglandular bodies in the background. Five aspirates showed rare eosinophilic myelocytes. Auer rods were not identified in any of the aspirates. Immunophenotypic and histochemical studies confirmed myeloid and/or myelomonocytic differentiation. GS especially can be confused with non-Hodgkin lymphoma because of morphologic similarities of the blasts to large cell lymphoma, the presence of lymphoglandular bodies, and the rarity of Auer rods and eosinophilic myelocytes. In conjunction with careful cytomorphologic evaluation, knowledge of the patient's clinical history and use of appropriate immunophenotypic studies should lead to a correct diagnosis.