Pleural Samples Research Articles

Diagnostic Performance of Unstimulated IFN-γ (IRISA-TB) for Pleural Tuberculosis: A Prospective Study in South Africa and India.

Tuberculous pleural effusion (TPE) is the most common form of extrapulmonary tuberculosis in many settings. The diagnostic performance of the frontline polymerase chain reaction-based GeneXpert MTB/RIF Ultra (Xpert Ultra) remains suboptimal (sensitivity of ∼30%), but data are limited. Improved diagnostic approaches are urgently needed to detect extrapulmonary tuberculosis (EPTB) in tuberculosis (TB)-endemic settings. This multicenter, prospective cohort study evaluated the diagnostic performance of a rapid (same-day) interferon gamma rapid immunosuspension assay (IRISA-TB) in patients with presumed TPE from South Africa and India. Participants underwent pleural biopsy, and testing with other available same-day diagnostic assays (adenosine deaminase [ADA], Xpert Ultra, and IRISA-TB) was concurrently undertaken. The reference standard for TB was microbiological and/or histopathological confirmation using pleural fluid and/or pleural biopsy samples. A total of 217 participants with presumed TPE were recruited (106 from South Africa, 111 from India). The sensitivity of IRISA-TB (cut-point 20.5 pg/mL) was significantly better than that of Xpert Ultra (81.8% [70.4-90.2] vs 32.9% [22.1-45.1]; P < .001) and ADA at the 40 IU/mL cut-point used in India (81.8% [70.4-90.2] vs 53.8% [41.0-66.3]; P = .002). Compared with ADA at the 30 IU/mL cut-point used in South Africa, IRISA-TB had a higher specificity (96.6% [90.3-99.3] vs 87.1% [78.6-93.2]) and a higher positive predictive value (94.7% [85.5-97.3] vs 81.8% [72.4-88.5]). The negative predictive value (NPV; rule-out value) of IRISA-TB was significantly better than that of Xpert Ultra (87.5% [83.2-93.0] vs 64.9% [61.1-68.6]; P < .001) and ADA at the 40 IU/mL cut-point (87.5% [83.2-93.0] vs 74.1% [68.7-79.0]; P < .001). IRISA-TB demonstrated markedly better sensitivity and NPV than Xpert Ultra and excellent specificity for the diagnosis of TPE. These data have implications for clinical practice in TB-endemic settings.

Correlation between thoracoscopic presentations and pathological patterns in undiagnosed pleural effusion

BackgroundPleural effusion is the most prevalent pleural disorder. One third of pleural effusions are caused by lung cancer. Thoracoscopy is regarded as the most reliable diagnostic method for the evaluation of suspected pleural malignancy.Aim and objectivesTo assess visible pleural characteristics of abnormalities and their locations for malignant and benign pathologies as well as to determine the incidence of malignancy in the apparent normal pleura.Patients and methodsThis was a descriptive, observational, and cross-sectional research that was performed on 36 cases with undiagnosed exudative pleural effusions prepared for medical thoracoscopy and on whom the cytological analysis was inconclusive, at the thoracoscopic Unit Department of Chest Diseases, Faculty of Medicine Zagazig University, from December 2023 to May 2024.ResultsThe apparent normal pleura and adhesions were significantly greater in benign effusions than in malignant effusions (p = 0.019 and p = 0.04, respectively), while nodular effusion was significantly greater in malignant effusions than in benign effusions (p = 0.003). Bleeding was significantly greater in malignant effusions than in benign effusions (p = 0.019). As regards the thoracoscopic findings, 24 (66.7%) patients showed nodular patterns, 14 (38.9%) patients showed adhesions, and two (5.6%) patients had pus, while six (16.7%) patients had apparent normal pleura. The costal pleura was the most frequently affected site (88.9%) followed by the visceral pleura (55.6%) then the diaphragmatic pleura (38.9%).ConclusionMedical thoracoscopy (MT), a minimally invasive and a generally safe treatment, enables the interventional pulmonologist to access the pleural cavity directly and obtain pleural samples under direct view helping in predicting the pathology.

Diagnostic accuracy of Xpert MTB/RIF and Xpert ultra tests in pulmonary and extrapulmonary tuberculosis compared to Löwenstein-Jensen culture

BackgroundTuberculosis (TB) is one of the leading causes of death worldwide. However, an accurate diagnosis contributes to timely treatment, reducing its adverse consequences. The aim of this research was to determine the diagnostic accuracy of the molecular test Xpert MTB/RIF and Xpert MTB/RIF Ultra (Xpert Ultra) for the diagnosis of pulmonary and extrapulmonary TB compared to Löwenstein-Jensen culture. MethodsWe conducted a cross-sectional study of diagnostic accuracy. We included samples from patients who attended a Peruvian laboratory between 2011 and 2022. The index test was the Xpert MTB/RIF and Xpert Ultra and the reference standard was Löwenstein-Jensen solid culture for Mycobacterium tuberculosis. We calculated sensitivity, specificity, and positive and negative likelihood ratios. ResultsWe evaluated 1023 samples, of which 737 were pulmonary samples, 197 tested positive for the Xpert MTB/RIF and Xpert Ultra tests; and 151 tested positive for culture. The Xpert (MTB/RIF and Ultra) showed a joint sensitivity and specificity of: 97 % (95%CI: 93–99) and 93 % (95%CI: 91–95) in pulmonary samples, 100 % (95%CI: 29.2–100) and 98.3 % (95%CI: 94.1–99.8) in cerebrospinal fluid, 66.7 % (95%CI: 22.3–95.7) and 96.8 % (95%CI: 91–99.3) in pleural fluid, 100 % (95%CI: 15.8–100) and 94.3 % (95%CI: 80.8–99.3) in urine. For the detection of pulmonary TB, the Xpert MTB/RIF had a sensitivity and specificity of 97.1 % (95%CI: 89.9–99.6) and 95.6 % (95%CI: 92.9–97.5) and the Xpert Ultra of 97 % (95%CI: 88.5–99.6) 89.5 % (95%CI: 84.9–93.1) respectively. ConclusionOur results suggest that the Xpert MTB/RIF and the Xpert Ultra are tests with high diagnostic performance for the detection of pulmonary TB and adequate specificity in pulmonary, cerebrospinal fluid, pleural, and urine samples. However, the results for other samples were imprecise.

Sago-grain nodules in tubercular pleural effusion.

A 6-year-old boy was referred with complaints of chest pain for 2 months with low-grade fever. A computerized tomography of the chest revealed a loculated pleural effusion on the left side. Medical thoracoscopy was performed that revealed a characteristic sago-grain follicle over the parietal pleural. Histopathology and microbiological investigations on pleural biopsy samples confirmed tubercular pleural effusion.

Insights into changing patterns of extrapulmonary tuberculosis in North India

PurposeTuberculosis is one of the dreadful infections and India contributes to substantial burden of TB cases globally. Though majority of cases are pulmonary, extra-pulmonary tuberculosis (EPTB) share significant burden, more in HIV-positive persons. Despite the striking burden, very few studies have been conducted in India and present study was undertaken to determine trends of EPTB at our tertiary care centre. MethodsThis was a retrospective study conducted over a period of 4 years 3 months. Diagnosis of EPTB was based on suspected clinical features, with positive micobiological evidence with cartridge based nucleic acid amplification test (CBNAAT) with/without microscopy. ResultsA total of 10,560 samples (pulmonary and extra-pulmonary) were received during the study period, of which 3972 were extrapulmonary. Of these, a total of 18% were noted to be positive for EPTB. Trend of positivity revealed highest burden in 2018 and a decline was noted over the years, however, rise in cases was noted in 2022. Pleural, meningitis, musculoskeletal, peritoneal and pericardial TB was more common in males, while lymphadenitis was more common in females (p value: <0.0001). Pleural TB (31%) was the most common presentation, followed by lymphadenitis. A gradual decline in lymphadenitis was noted with significantly increasing trend only for musculoskeletal TB. Rifampicin resistance was detected in 7.45% of positive samples, of which the maximum rate of resistance was noted in lymph node aspirates (11.11%), followed by musculoskeletal and pleural samples. ConclusionThe present study showed a gradual decline in positivity of EPTB cases over the years. Younger productive age group with more propensity to transmit infection was the most commonly affected, with pleural TB as the most common presentation. Rare presentations of EPTB also contributed major share. Higher rates of resistance underline requisite to strengthen ongoing programs, to achieve the End TB strategy by 2025.

Methodological and TNM Focus-Based Comparison of EGFR Mutation Status in Non-Small-Cell Lung Carcinomas.

Epidermal growth factor receptor (EGFR) mutations in non-small-cell lung carcinomas (NSCLC) are a frequent class of driver mutations, and tyrosine kinase inhibitor (TKI) therapy provides considerable clinical benefits. Using the most effective and also easiest method for EGFR analysis is cost-effective and time-saving. In this study, we aimed to determine which method could be more effective by comparing the incidences of EGFR mutations in cytological and histological samples which were obtained by different methods also, whether there was a difference in the incidences of EGFR mutations between the primary foci, mediastinal lymph nodes, and distant metastatic foci. We retrospectively reviewed 420 cases of cytological materials, small biopsies, and surgical samples reported as NSCLC underwent EGFR analysis in our department between 2016 and 2022. We collected the data and interpreted the results from two different perspectives. We identified 36 EGFR mutations in 362 biopsies (9.94%) and 17 in 58 cytology samples (29.31%). There is a significant difference between the two methods (P = 0.01*). We observed 38 EGFR mutations in 320 primary foci (11.87%), 7 EGFR mutations in 36 mediastinal or subcarinal lymph nodes (19.44%), and 8 EGFR mutations in 64 distant metastatic foci (12.50%). A significant difference was also observed in pleural samples (P = 0.005*). We observed more successful results with cell blocks obtained from liquid-based cytological specimens than with formalin-fixed, paraffin-embedded tissues obtained from resection or otherwise in our clinical routine. Our study results highlight the benefits of cytological specimens in molecular treatments and current therapy modalities.

Pleural mesothelioma from fluoro-edenite exposure: PACAP and PAC1 receptor. A preliminary report.

Pleural mesothelioma is a devastating malignancy primarily associated with asbestos exposure. However, emerging evidence suggests that exposure to fluoro-edenite fibers, a naturally occurring mineral fiber, can also lead to the development of pleural mesothelioma. In this study, based on the hypothesis that pituitary adenylate cyclase-activating polypeptide (PACAP) and PACAP-preferring receptor (PAC1R) expressions could be dysregulated in pleural mesothelioma samples and that they could potentially act as diagnostic or prognostic biomarkers, we aimed to investigate the immunohistochemical expression of PACAP and PAC1R in pleural biopsies from patients with pleural mesothelioma exposed to fluoro-edenite fibers. A total of 12 patients were included in this study, and their biopsies were processed for immunohistochemical analysis to evaluate the expression of PACAP and its receptor. The study revealed a correlation between the overexpression of PACAP and PAC1R and shorter overall survival in patients with malignant mesothelioma. These findings suggest that PACAP and PAC1R expression levels could serve as potential prognostic biomarkers for malignant mesothelioma. Furthermore, the immunohistochemical analysis of PACAP and PAC1R may provide valuable information for clinicians to guide therapeutic decisions and identify patients with poorer prognosis.

Sulfuric Acid Ingestion: May the Severity of the Metabolic Acidosis be Considered as a Predictive Sign of Late Damage to the Gastrointestinal Tract?

Caustic substances ingestion results in a complex syndrome. The patient characteristics and severity of injury are important prognostic predictors. The monitoring of clinical changes and the multidisciplinary approach are necessary to prevent death in the early stages of the poisoning. The case report describes the suicide of a woman by ingestion of a large amount of 15% sulfuric acid for suicidal purposes (15-20 ml). The initial conditions were stable, and no changes were found on a CT scan. However, the main sign was a severe metabolic acidosis. After 7 hours, haematemesis and oedema of the larynx appeared, and oro-tracheal intubation and ICU admission were necessary. Consequent progressive haemodynamic deterioration with persistent severe metabolic acidosis, increasing lactates and septic shock appeared. A new CT scan with contrast was performed 22 hours later detecting diffuse perforations and liquid in pleurae and abdomen. A pleural sample showed necrotic liquid. The death was 24 hours after ingestion and no surgical treatment was performed because of the diffuse lesions to the thoracoabdominal districts. Early detection of gastroenteric lesions and the monitoring of clinical changes are mandatory to avoid the death of the patient. Gastroenteric perforations require an immediate radiological evaluation and surgical treatment. The clinical case report states the severity of prognosis was related to high doses of sulfuric acid ingestion. The immediate metabolic acidosis is related to quick subsequent severe systemic pathological lesions of the gastrointestinal tract. The severity of absorption metabolic acidosis, consequently, may be an early and prognostic sign of the late chest and abdominal lesions. Severity of metabolic acidosis after sulfuric acid ingestion may anticipate late damage to the gastrointestinal tract.

Safety and Diagnostic Yield of Medical Pleuroscopy (MP) Performed under Balanced Analgosedation by a Pneumological Team Compared to Video-Assisted Thoracic Surgery (VATS): A Retrospective Controlled Real-Life Study (TORAPO).

Medical pleuroscopy (MP) is an invasive technique that provides access to the pleural space with a rigid or semi-rigid work instrument, allowing for visualization and the obtaining of bioptic pleural samples. Using pulmonologist-based analgosedation to perform pleuroscopy is still debated for safety reasons. The aim of this real-life study is to demonstrate the safety and diagnostic yield of MP performed under balanced analgosedation by a pulmonologist team with expertise in the management of critically ill patients in the respiratory intensive care unit (RICU) and interventional pulmonology unit as compared to video-assisted thoracic surgery (VATS) performed by a thoracic surgeon team under anesthesiologist-based analgosedation. In this multicentric retrospective controlled study, the inclusion criteria were patients older than 18 years old with pleural effusion of unknown diagnosis consecutively admitted in the years 2017-2022 to the pulmonology unit and RICU of San Donato Hospital in Arezzo (Italy, Tuscany) and to the thoracic surgery unit of Santa Maria Le Scotte in Siena (Italy, Tuscany) to undergo, respectively, MP under balanced propofol-based analgosedation on spontaneous breathing with local anesthesia provided by a pulmonologist team (Group A), and VATS provided by a surgeon team under propofol-based analgosedation managed by an anesthesiologist using invasive mechanical ventilation (IMV) via endotracheal intubation (ETI) (Group B). The primary endpoints were (1) a comparison between the two groups in terms of the diagnostic yield of pleural effusion, and (2) major and minor complications of pleuroscopic procedures. The secondary endpoints were (1) the length of the pleuroscopic procedure; (2) the duration of hospitalization; (3) propofol doses; and (4) the patient's comfort after the procedure assessed using the Visual Analogue Scale (VAS). We enrolled 91 patients in Group A and 116 patients in Group B. A conclusive diagnosis was obtained in 97.8% of Group A vs. 100% of Group B (p = 0.374). Malignant effusion was diagnosed in 59.3% of Group A and in 55.1% of Group B; p = 0.547. No intraoperative or postoperative mortality events or major complications were observed in Group A. The major complications observed in Group B were three major bleeding events (p = 0.079) and one exitus (p = 0.315) not related to the interventional procedure. No significant difference emerged between the two groups in terms of minor complications. The duration of the intervention was significantly lower in Group A (40.0 min ± 12.6 versus 51.5 ± 31.0; p = 0.001). Pain control and, therefore, patient comfort were better in Group A, with an average VAS of 0.34 ± 0.65 versus 2.58 ± 1.26, p < 0.001. The duration of hospitalization was lower in Group B (5.1 ± 2.6 vs. 15.5 ± 8.0, p < 0.001). The average overall dose of propofol administered was significantly lower in Group A (65.6 ± 35.8 mg versus 280 ± 20.0 mg; p < 0.001). This real-life study shows that the MP performed under propofol-based analgosedation by an independent pneumologist team is a safe and well-tolerated procedure with a diagnostic yield and complication rates similar to those obtained with VATS.

Septicemic salmonellosis in suckling piglets resulting from improper intramuscular administration of an oral vaccine.

We describe an unusual outbreak of mortality in suckling piglets following the misadministration of an oral vaccine against Salmonella Typhimurium and Salmonella Choleraesuis. Within 3-48 h of vaccination of a batch of ~700 piglets, ~300 developed marked swelling in the dorsal neck region, respiratory distress, fever, recumbency, and apathy. In total, ~100 died, and 4 were submitted for autopsy. Gross and microscopic lesions consisted of focally extensive areas of purple discoloration in the skin of the cervical region, associated with edema and hemorrhage in the subcutis and muscles. Additionally, there was interstitial pneumonia with marked interlobular edema and mild fibrinous pleuritis. Aerobic bacterial culture identified Salmonella Typhimurium (3 cases) and Salmonella Choleraesuis (1 case) in samples of skeletal muscle and lung and from pleural swab samples. Marked immunostaining against Salmonella spp. was observed in the skeletal muscle of the cervical region, as well as in blood vessels and macrophages from the lung, liver, spleen, and kidney. We concluded that inappropriate intramuscular administration of an oral vaccine against Salmonella resulted in septicemia and death in a batch of piglets.

Retrospective validation of MetaSystems' deep-learning-based digital microscopy platform with assistance compared to manual fluorescence microscopy for detection of mycobacteria.

This manuscript presents a full validation of MetaSystems' automated acid-fast bacilli (AFB) smear microscopy scanning and deep-learning-based image analysis module using a probability threshold of 96% including accuracy, precision studies, and evaluation of limit of AFB detection on respiratory samples when the technology is used with assistance. This study is complementary to the conversation started by Tomasello et al. on the use of image analysis artificial intelligence software in routine mycobacterial diagnostic activities within the context of high-throughput laboratories with low incidence of tuberculosis.

Usefulness of Xpert MTB/RIF Ultra for rapid diagnosis of extrapulmonary tuberculosis in Tunisia

Extrapulmonary tuberculosis (EPTB) remains a challenging diagnosis. The purpose of this study was to assess the accuracy of Xpert MTB/RIF Ultra (Cepheid, USA) for rapid diagnosis of EPTB in Tunisia. Eight hundred and forty-seven extrapulmonary samples collected from 2017 to 2021, were subjected to Xpert MTB/RIF Ultra. Microscopy and culture were performed for all the specimens. The accuracy of Xpert Ultra was evaluated in comparison to the culture. Xpert Ultra diagnosed EPTB with a global sensitivity of 80.66% (74.3–85.75) and specificity of 70.87% (67.31–74.20). The molecular test was most accurate when performed in cerebrospinal fluids, bones and joints and cutaneous specimens showing a sensitivity of 100% and a specificity ranging from 70.60 to 91.11%. In lymph node samples comprising aspirates and biopsies, the sensitivity of Xpert Ultra was high 87.50% (77.23–93.53), however, the specificity was 51.08% (44.67–57.46). For pleural samples, the Xpert Ultra sensitivity was 77.50% (68.34–84.68) ranging from 71.43 to 80% in pleural biopsies and fluids respectively. The specificity in all pleural specimens was 79.56% (74.40–83.91). Xpert Ultra showed promise in the diagnosis of EPTB. The performances varied according to the site of the disease. The test may be more valuable if used in combination with other diagnostic modalities.

Investigation of MTAP and BAP1 staining loss and P16/CDKN2A deletion in pleural cytology specimens and its role in the diagnosis of mesothelioma.

Mesothelioma is a malignant neoplasm with a poor survival rate. We aimed to investigate the importance of BAP1, MTAP (IHC), and p16/CDKN2A homozygous deletion (FISH) in cytologic material obtained from pleural effusion sampling, which is a less invasive procedure in the diagnosis of mesothelioma. Our study discussed pleural cytology samples of cases with histopathologically proven mesothelioma diagnoses between 2017 and 2022. As the control group, materials that had pleural effusion sampling for other reasons and reactive mesothelial hyperplasia were included in the study. Cell blocks prepared from these materials were subjected to fluorescent in situ hybridization for p16/CDKN2A homozygous deletion and immunohistochemistry for BAP1 and MTAP. The specificity of the P16/CDKN2A homozygous deletion in diagnosing mesothelioma is 100%. Its sensitivity is 68.75%. The specificity of BAP1 immunohistochemical nuclear expression loss is 95%, while the sensitivity is 60%. Loss of nuclear expression of MTAP alone has the lowest specificity and sensitivity, with a specificity of 86% and a sensitivity of 43%. The highest sensitivity is reached when BAP1 loss and p16/CDKN2A homozygous deletion are evaluated together, increasing to 81%. The specificity is 95%. It has been determined that any marker alone cannot be used for a definitive mesothelioma diagnosis in pleural effusion cytological specimens; however, sensitivity increases in some combinations. The combination of BAP1 immunohistochemistry and p16/CDKN2A homozygous deletion detected by FISH, which has a higher specificity and sensitivity, can be routinely used in the diagnosis of mesothelioma under the guidance of clinical and radiologic information.

Pleural fluid residue as a diagnostic tool for cytology-negative malignant pleural effusion: A proof-of-concept study.

Pleural fluid residue, or macroscopic tissue, circulating freely in the pleural fluid obtained through direct filtration, may carry diagnostic histopathological information. We aimed to determine the histopathological concordance of pleural fluid residue in diagnosing TPE and MPE, compared with conventional pleural biopsy. This was a prospective cohort study of consecutive inpatients with cytology-negative exudative effusion who underwent pleuroscopy and had their initial suctioned pleural fluid filtered for residue samples. Pleural fluid residue demonstrated malignant cells in four out of seven cases of pleural biopsy-confirmed malignancy. Pleural fluid residue has comparable cytomorphology but reduced cellularity compared with pleural biopsy. No tuberculous histological features were present in the pleural fluid residue samples. In this preliminary study pleural fluid residue provided histopathological information for malignant pleural effusion, but no incremental diagnostic information for tuberculous effusion. However larger and more definitive studies are required to clarify these findings, and to explore the utility and suitability of pleural fluid residue for mutational analysis. This study demonstrates the potential of pleural fluid residue as a non-invasive diagnostic method for confirming malignancy in cytology-negative exudative effusion. In resource-limited settings or patients contraindicated for pleural biopsy, pleural fluid residue may provide a viable diagnostic alternative; however, this observation needs further validation.

Rapid detection of S. pyogenes and S. pneumoniae in pleural fluid for diagnosis of parapneumonic empyema.

The aim of this study was to assess the reliability of rapid antigen detection tests (RADT) for Streptococcus pyogenes (GAS) and Streptococcus pneumoniae on pleural fluid samples for diagnosis of parapneumonic effusion/empyema (PPE) and their potential for improving pathogen identification rates. Sixty-three pleural samples were included from 54 patients on which GAS and S. pneumoniae RADT (BinaxNOW), culture, 16S rRNA PCR, and S. pneumoniae-specific PCR were performed. GAS RADT showed a sensitivity of 95.2% and a specificity of 100%. Pneumococcal RADT showed a sensitivity of 100% and specificity of 88.6%. Both RADT increased the pathogen identification rate in PPE compared to culture.

High Fluorescent Cells on Automated Body Fluid Analysis as Discriminator for Malignant Cell Detection

The automated examination of body fluids (BF) serves as a valuable screening tool for the presence of malignant cells in such samples. Malignant cells are identified as high fluorescence cells (HFC) when analyzed using the Sysmex XN-1000 automated analyzer. This study aimed to assess the correlation between HFC cell counts generated by the automated analyzer and manual cytological examination for detecting malignant cells. Additionally, it sought to establish reliable cutoff values for malignant cells since there is a lack of literature on this subject. Conducted at the department of pathology hematology and cytology laboratory in a tertiary care hospital in India from January 2019 to May 2020, this hospital-based comparative study analyzed 120 BF samples, each subjected to cytological evaluation. The mean age of the study population was 52 years, with 70 male and 50 female patients (male-to-female ratio of 1.4:1). The samples consisted of 53 ascitic fluids (44.17%), 46 pleural fluids (38.33%), and 21 cerebrospinal fluids (CSF; 17.50%). Cytopathological examination revealed malignant cells in 50 (41.67%) of the BF samples, with 70 (58.33%) samples classified as nonmalignant. Specifically, among the ascitic fluids, 24 (48%) were malignant, while 29 (41.43%) were nonmalignant. For pleural fluids, 24 (48%) were malignant, and 22 (31.43%) were nonmalignant. In CSF, 2 (4%) samples were malignant, and 19 (27.14%) were nonmalignant. The total white blood cell counts provided by automated hematology analyzers were significantly higher in malignant samples, ranging from a minimum of 100 cells to a maximum of 60,000, with a median count of 800. Nonmalignant samples had white blood cell counts ranging from 2 to 12,000, with a median count of 100. Subgroup analysis for ascitic, pleural, and CSF samples revealed significantly higher median HFC counts in malignant samples. Receiver operating characteristic curve analysis indicated that the HF-BF parameter could effectively distinguish between benign and malignant fluids. For HF#, the area under the curve (AUC) was 0.844, with a sensitivity of 82% and specificity of 81%, while HF% had an AUC of 0.706, with sensitivity and specificity values of 72% and 72.9%, respectively. This study highlights that the HFC count in the BF mode of Sysmex XN-1000 can be a valuable tool for predicting the presence of malignant cells in serous fluids and for selecting samples for further microscopic examination. Based on this study, cutoff values of 15.70/µL for absolute HFC count and 5.05% for relative HFC count can be applied to screen BF samples for malignancy, offering good sensitivity and specificity.

Pleural penetration of amoxicillin and metronidazole during pleural infection: An ambispective cohort study

The pharmacokinetics of antibiotics in pleural fluid during pleural infections has been poorly described. This study aimed to explore amoxicillin and metronidazole diffusion into the pleural space. This was an ambispective, single-centre study that included patients with complicated parapneumonic effusion or pleural empyema managed with repeated therapeutic thoracentesis as first-line treatment between 2014 and 2022. Pleural steady-state or trough concentrations of amoxicillin and metronidazole were measured, with a lower limit of quantification of 5 mg/L. Seventy paired blood and pleural samples were analysed from 40 patients. The median (interquartile range) patient age was 55 years (45-67 years) and 88% were male. The median patient weight was 65.8 kg (57.3-82 kg) and median plasma albumin concentration was 29.7 g/L (23.7-33.9 g/L). Median creatinine clearance was 106 mL/min (95-117 mL/min). Median amoxicillin pleural concentrations in patients treated with oral, bolus and continuous intravenous administrations (6 g/day) were, respectively, 5.2 (<5-6.4), 9.4 (8-13.1) and 10.8 (7.1-13.1) mg/L. Pleural concentrations were <5 mg/L in 5/11 samples (45%) with oral treatment and 6/59 (10%) with intravenous treatment. Median metronidazole pleural concentrations were 18.4 (15.7-22.8) mg/L, with all patients being treated orally (1.5 g/day). Oral metronidazole (1.5 g/day) and intravenous amoxicillin (6 g/day) achieved therapeutic targets in pleural fluid in most cases, but oral amoxicillin did not.

The role of CD24 as a potential biomarker for malignant pleural mesothelioma

Abstract Objectives Pleural mesothelioma is a rapidly progressing pleural neoplasm caused by asbestos exposure of a long latency around 30-40 years. Patients with mesothelioma are usually diagnosed at a late stage with poor outcomes in terms of morbidity and mortality with 6–12 months’ median survival. Despite the prohibited use of asbestos, malignant pleural mesothelioma is still increasingly being occurred in young age and female patients. Different un-standardized biomarkers have been used to diagnose MPM as mesothelin and febulin with controversial results, so we used CD 24 as a biomarker to diagnose and differentiate between different subtypes of malignant pleural mesothelioma. Materials and methods Our cohort study included total of fifty-nine patients with exudative pleural effusion. All patients underwent full history taking, clinical examination, blood tests (CBC, coagulation profile, liver and kidney functions), tapping of pleural effusion and to send pleural fluid investigations for LDH, albumin, total protein and albumin, then confirmed exudative pleural effusion patients were subjected to thoracic ultrasonography and medical thoracoscopy for the majority of cases or ultrasound guided biopsy in selected cases to obtain pleural biopsies for histopathology and then the examination of pleural biopsies for CD24 expression. Results Our study demonstrated the possibility of using CD24 as a biomarker in the immunostaining of pleural biopsies to differentiate between malignant pleural mesothelioma and pleural malignancy other than mesothelioma (18 mesothelioma cases versus 2 nonmesothelioma malignant cases) with high statistical significance P value &lt; 0.001 and also it can discriminate between subtypes of mesothelioma as it showed marked significance in epithelioid subtype (12 epithelioid versus 1 sarcomatoid versus 5 biphasic subtypes) with more uptake by score +2 in epithelioid mesothelioma. Conclusions CD24 can be supposed to be a routine biomarker for immunohistochemistry of pleural tissue samples in diagnosis of mesothelioma and it can be used to differentiate between subtypes of malignant mesothelioma subtypes.

A-111 There is More to Diluting Icterus Interference than Meets the Eye

Abstract Background Total protein is measured in serum and body fluids as part of routine evaluations of general nutritional status and differentiating exudative and transudative effusions. Spectral interference thresholds for bilirubin (e.g., icterus) is set by assay manufacturers to prevent inaccurate results from being reported. The Roche Cobas serum total protein assay package insert states no significant interference from bilirubin up to an icterus (I) index of 20. Body fluids tend to have lower total protein concentrations; therefore, thresholds were derived during prior validation studies and set to I = 10, a threshold that is exceeded routinely. Laboratories can mitigate some interferences by recollecting (e.g., hemolysis) or ultracentrifuging (e.g., lipemia) specimens. Serial dilutions are another option used; however, it is imperative that the laboratory understands the mechanism of interference and can demonstrate that it is mitigated by sample dilution. The aim of this study was to investigate whether bilirubin interference can be mitigated by sample dilution in pleural fluid, peritoneal fluid, and serum specimens. Methods Residual clinically ordered pleural fluid (n = 3), peritoneal fluid (n = 3), and serum (n = 3) samples submitted for protein testing were split into two equal volume aliquots with concentrations ranging 2.7 to 4.3 g/dL in pleural fluids, 3.9 to 5.4 g/dL in peritoneal fluids, and 3.8 to 11.0 g/dL in serum. One aliquot was spiked (&amp;lt;10% by volume) with a bilirubin conjugate solution (∼1000 mg/dL) to surpass the icterus index threshold (spiked). The second aliquot was spiked with an equal volume of 0.9% saline (control). Total protein was measured on the Roche Cobas c701 instrument in both samples to calculate difference (Spiked-Control). The mean(SD) difference was calculated for each sample type. Each spiked sample was serially diluted (2-fold, 4-fold and 8-fold) with 0.9% saline. Total protein was measured for each diluted sample. Mean(SD) difference was calculated (DilutedX-Control), where X = 2-fold, 4-fold, 8-fold. Linear regression analysis was performed by plotting the measured (x-axis) vs expected (y-axis) total protein concentration. Slope, y-intercept, and R2 were determined from serially diluted samples where the expected concentrations were derived using the spiked concentration to replicate the practice of diluting an icteric sample. Results Bilirubin spiking (average icterus index = 33.5) into pleural fluid, peritoneal fluid, and serum, respectively demonstrated mean(SD) bias (g/dL) = −1.0(0.2), −0.9(0.0), and −0.7(0.0). Subsequent 2-fold dilution demonstrated mean(SD) bias (g/dL) = −1.0(0.2), −1.0(0.0), and −0.8(0.1), 4-fold dilution with mean(SD) bias (g/dL) = −1.1(0.2), −1.0(0.0), and -1.0(0.1), and 8-fold dilution with mean(SD) bias (g/dL) = −1.3(0.2), −1.0(0.0), and −1.4(0.1). Diluting pleural, peritoneal, and serum samples, respectively spiked with bilirubin resulted in slope = 0.99, 1.00, and 0.99; y-intercept = 0.04, 0.01, and 0.07; R2 = 0.99, 0.99, 0.99. Conclusion The dilutions exhibited a linear dilution response, however the dilution results never returned to baseline (non-spiked) concentration. Laboratories should exercise caution when conducting serial dilutions to diminish bilirubin interference in samples when measuring total protein as the mechanism of interference does not appear to be reversible by dilution. This behavior was demonstrated in both body fluids and serum.

ACCURACY OF AUTOMATED CELL ENUMERATION METHOD FOR VARYING CONCENTRATION OF WBCS FOR VARIOUS BODY FLUID SAMPLES

Background: Body fluids (BF) including peritoneal, pericardial, pleural, synovial and cerebrospinal fluids are now being analyzed by fully automated methods that are replacing the manual methods. The aim of this study is to assess the accuracy of automated instrument at varying concentrations of WBCs of various body fluid samples. Material and Methods: This cross-sectional study was conducted at the section of Hematology, Department of Pathology and Laboratory Medicine, the Aga Khan University, Karachi, Pakistan from November 2020 to April 2021. Forty body fluid samples with suspicion of infection including peritoneal, pericardial, pleural, synovial and cerebrospinal fluids (CSF) were analyzed to verify accuracy of white blood cells counts on fully automated XN-1000TM hematology analyzer (Sysmex Corporation, Kobe, Japan) against Neubauer chamber method (a manual method of differentiating WBCs via microscopy). The culture results of the body fluid samples were also analyzed. EP Evaluator version 10.3.0.556 (Data Innovations, LLC, VT, US) was used for statistical analysis with other supporting statistics such as Correlation Coefficient (R), Bias, Mean and Standard Deviation were included. Results: Eleven (n=11) of forty (n=40) body fluid samples showed high WBC count above the normal range. Samples with normal WBC (n=29) were also included in accuracy study to assess instrument performance at varying concentration of analyte. An average Error Index of -0.27 (-0.99 to 0.74) for WBC was obtained. Microbiological cultures grew Escherichia. Coli in 1 and Acinetobacter species in 1 CSF samples and Staphylococcus Aureus in 1 pleural sample. Conclusion: The study verified accuracy of varying concentration of WBC counting by fully automated Sysmex XN-1000 analyzer for various body fluid samples. Keywords: Body fluids, Validation, Automated analyzer, Performance specifications, Accuracy verifications, High white blood count, Infectious.