Serous Fluid Research Articles

A 24 kgs giant mucinous cystadenoma in a post-menopausal woman: A rare case report

Mucinous cystadenomas are among the most common benign ovarian neoplasms. Abdominal cystic tumours are highly prevalent. Due to the availability of superior imaging techniques, they are now diagnosed more commonly and considerably earlier. Over time, these adnexal masses can lead to fatal complications, such as ovarian torsion or haemorrhage. Incidental findings of these tumours are common as many of these patients are asymptomatic. 45-year-old female presented with abdominal distension for 1 year with polymenorrhagia. An exploratory laparotomy relieved a giant tumour weighing of 24.870 kgs drained 30 Litres of serous fluid. Histopathology revealed benign ovarian mucinous cystadenoma. A multidisciplinary approach in the preoperative, intraoperative and postoperative stages of management optimizes patient outcomes.

Flow cytometry, molecular analysis, and other special techniques (in Serous Fluid Cytopathology).

Morphological and architectural pattern evaluations play a major role in the rpretation of hematopoietic neoplasms. However, confirmation of diagnosis, classification, prognosis, and risk stratification are highly dependent on the utilization of multiple ancillary studies. The importance of these ancillary studies increases in evaluating serous fluid samples, as these samples lack architecture and patterns. Likewise, the morphology can be disturbed by sample preparation. The most common ancillary studies utilized are flow cytometry, immunohistochemistry for immunophenotyping, Fluorescent In Situ Hybridization (FISH), cytogenetics for structural and gene rearrangements, and molecular studies for mutational analysis. Among them, flow cytometry analysis is the handiest test to perform with high diagnostic yield on serous fluid specimens. In this article we will discuss the use, caveat, and role of the most common ancillary studies on serous fluid specimen evaluation. This review article will be incorporated finally as one of the chapters in CMAS (CytoJournal Monograph/Atlas Series) #2. It is modified slightly from the chapter by the initial authors (Choladda Vejabhuti, MD and Chung-Che (Jeff) Chang, MD, PhD) in the first edition of Diagnostic Cytopathology of Serous Fluids.

Serous fluid: Reactive conditions.

This chapter highlights the steps that would help to analyze any fluid. It highlights importance of knowing gross analysis of fluid along with biochemical information. These parameters along with clinical information are very important in arriving at a differential diagnosis. Morphologic appearances in the fluid can often become challenging and occasionally reactive conditions can reveal changes that may mimic malignancies. This chapter provides not only a framework of approach to assessment of fluid cytology but also shows how to distinguish some of the challenging reactive conditions from the diagnosis of carcinoma. The chapter also utilizes two cases to demonstrate approach to reactive conditions. This review article will be incorporated finally as one of the chapters in CMAS (CytoJournal Monograph/Atlas Series) #2. It is modified slightly from the chapter by the initial authors in the first edition of Cytopathologic Diagnosis of Serous Fluids.

Serous fluid: Metastatic sarcomas, melanoma, and other non-epithelial neoplasms.

While most tumors metastatic to the serous membranes are of epithelial origin, cytologists should be aware that non-epithelial neoplasms can also cause malignant effusions including sarcomas, melanomas, germ cell tumors, and, more rarely, brain tumors. The differential diagnosis of a malignant effusion is accordingly broad, especially for the small round blue cell tumors that includes not only mesenchymal tumors, but also non-mesenchymal tumors, such as neuroblastoma and Wilms tumor. Diagnosing non-epithelial malignancies in effusion specimens based entirely upon their cytomorphologic features is difficult because these neoplasms often exhibit considerable morphological overlap and their cytomorphology can differ from the original tumor. As malignant cells have a tendency to round up in body fluids these non-epithelial neoplasms can therefore mimic reactive mesothelial cells and metastatic adenocarcinoma. The use of ancillary studies including immunostaining, FISH, and molecular studies is thus often critical to reach a definitive diagnosis. This review article will be incorporated finally as one of the chapters in CMAS (CytoJournal Monograph/Atlas Series) #2. It is modified slightly from the chapter by the initial authors in the first edition of Diagnostic Cytopathology of Serous Fluids.

Serous fluids and hematolymphoid disorders.

Diagnosing hematolymphoid neoplasm by evaluating fine-needle aspiration (FNA) cytology sample is controversial and requires experience and clinical skills. This concept becomes more challenging when evaluating hematolymphoid neoplasm in body fluid. Differentiating between low-grade lymphoma and reactive lymphocytes is often difficult by morphology alone as reactive lymphoid cells may acquire activation morphology from being exposed to different cytokines within the body fluid. However, in most cases there are specific features that may aid in differentiating small reactive from non-reactive lymphocytes including the round shape of the nucleus, the absence of visible nucleoli and the presence of fine clumped chromatin. In large cell lymphoma and leukemia cells involvement of body fluid this concept becomes less challenging. Large cell lymphoma and leukemia cells tend to have large size nuclei, less mature chromatin, and visible nucleoli with and without cytoplasmic vacuoles. However, to reach accurate diagnosis and subclassification, the utilizing of flow cytometry, to confirm monoclonality, and other ancillary studies such immunocytochemistry, cytogenetics and molecular studies is needed. This review article will be incorporated finally as one of the chapters in CMAS (CytoJournal Monograph/Atlas Series) #2. It is modified slightly from the chapter by the initial authors in the first edition of Diagnostic Cytopathology of Serous Fluids.

Serous cavity metastasis: Evaluation of unknown primary.

Malignant effusions can occur in patients with neoplasia. Once a metastatic diagnosis is confirmed, the primary site of origin of malignancy needs to be ascertained. This task can be challenging without a prior history of malignancy. In some patients their effusion may be the initial presentation of an underlying malignancy. Metastases usually present with a dual population of mesothelial and malignant cells. Combining cytomorphologic examination with ancillary testing such as immunocytochemistry can help identify the origin of the foreign malignant cell population. Helpful architectural clues include a single cell pattern, solid cell ball pattern, single file arrangement, papillary formation, psammoma bodies and background mucin. Useful cellular features include the presence of signet ring cells, small cells, pleomorphic and multinucleated giant cells, squamous cells, spindle cells and pigmentation. Rarely, despite an extensive work-up the primary site of origin for a malignant effusion may remain unresolved. This review article will be incorporated finally as one of the chapters in CMAS (CytoJournal Monograph/Atlas Series) #2. It is modified slightly from the chapter by the initial authors in the first edition of Cytopathologic Diagnosis of Serous Fluids.

Application of the International System for Reporting Serous Fluid Cytopathology (TIS): A retrospective institutional study

AbstractBackgroundCytology of serous effusions is an important diagnostic tool for the diagnosis of cancer, staging, and prognosis of the patient. Herein, we retrospectively applied the International System for Reporting Serous Fluid Cytopathology (TIS) and provided the corresponding risks of malignancy (ROMs).MethodsPleural, pericardial, and peritoneal effusion samples were retrieved from the archives of our department and reclassified according to the TIS. The ROM for each category was calculated based on available surgical follow‐up.ResultsA total of 3790 effusions were studied. Pleural samples (1292) were reclassified as follows: 27 (2.1%) as non‐diagnostic (ND), 1014 (78.5%) as negative for malignancy (NFM), 86 (6.6%) as atypia of undetermined significance (AUS), 29 (2.3%) as suspicious of malignancy (SFM), and 136 (10.5%) as malignant (M). Pericardial samples (241) were reclassified as follows: 4 (1.6%) as ND, 173 (71.8%) as NFM, 10 (4.1%) as AUS, 7 (3%) as SFM, and 47 (19.5%), as M. Peritoneal cases (2257) were re‐categorised as follows: 31 (1.4%) as ND, 1897 (84%) as NFM, 39 (1.7%) as AUS, 53 (2.4%) as SFM, and 237 (10.5%) as M. The respective ROM values for each category were 18.5%, 15%, 45.3%, 93%, and 100% in pleural effusions; 25%, 13.2%, 35%, 100%, and 100% in pericardial effusions; and 19.3%, 10.4%, 43.5%, 100%, and 100% in peritoneal effusions.ConclusionsPleural, pericardial, and peritoneal cytology show high specificity and moderate sensitivity in the evaluation of serous effusions. The ROMs reported in our study were mostly concordant with those published according to the TIS.

Highly Pathogenic PRRSV-Infected Alveolar Macrophages Impair the Function of Pulmonary Microvascular Endothelial Cells.

The porcine reproductive and respiratory syndrome virus (PRRSV), especially the highly pathogenic strains, can cause serious acute lung injury (ALI), characterized by extensive hemorrhage, inflammatory cells and serous fluid infiltration in the lung vascular system. Meanwhile, the pulmonary microvascular endothelial cells (PMVECs) are essential for forming the air–blood barrier and keeping the water–salt balance to prevent leakage of circulating nutrients, solutes, and fluid into the underlying tissues. As well, they tightly regulate the influx of immune cells. To determine the possible relationship between the PMVECs’ function changes and lung vascular permeability during PRRSV infection, the PMVECs were co-cultured with HP-PRRSV-inoculated primary pulmonary alveolar macrophages (PAMs) in transwell model, and then the RNA sequencing (RNA-seq) and comprehensive bioinformatics analysis were carried out to characterize the dynamic transcriptome landscapes of PMVECs. In total, 16,489 annotated genes were identified, with 275 upregulated and 270 downregulated differentially expressed genes (DEGs) were characterized at both 18 and 24 h post PRRSV inoculation. The GO terms and KEGG pathways analysis indicated that the immune response, metabolic pathways, cell death, cytokine–cytokine receptor interaction, viral responses, and apoptotic process are significantly regulated upon co-culture with PRRSV-infected PAMs. Moreover, according to the TERR and dextran flux assay results, dysregulation of TJ proteins, including CLDN1, CLDN4, CLDN8, and OCLN, is further confirmed to correlate with the increased permeability of PMVECs. These transcriptome profiles and DEGs will provide valuable clues for further exploring the roles of PMVECs in PRRSV-induced ALI in the future.

Persistent Methicillin-Resistant Staphylococcus Aureus Bacteremia Secondary to Infected Seroma: A Rare Case Report

A seroma is defined as a serous fluid collection that develops as a response to injury and surgeries, particularly mastectomy and reconstructive and abdominal surgeries. The majority of the seromas are self-limiting and arise in the acute postoperative period; however, diagnosis of seroma several years after surgery has also been reported in the literature. Persistent bacteremia with infected seroma as a source is a rare entity. We present the first case to be reported of persistent bacteremia secondary to infected seroma with septic emboli to lungs and prostate without any evidence of endocarditis on multiple echocardiograms. This case highlights the importance of meticulous physical examination and source control in the management of bacteremia.

Diagnostic Dilemma During Laparoscopic Cystectomy of Twisted Serous Cystadenofibroma of Ovary in Adolescent Girl – A Case Report with Literature Review

The most ovarian tumor arises from the surface epithelium and the serous tumor is the most common histological variant. Serous cystadenofibroma is a rare variant of serous tumor that comprises both epithelial and fibrous stromal components. They are benign in nature but may often be misinterpreted as malignant nature due to their solid cystic nature with papillary projections. We herein report a case of twisted right ovarian cyst in 17 years unmarried girl that was clinically and radiologically benign and hence managed laparoscopically. Intraoperatively cyst ruptured that released clear serous fluid. During cystectomy, multiple small to large size (maximum 2x2 cm) papillary projections were noted within the uninoculated cyst without any other solid components. With the possibility of a borderline tumor, the patient party was counseled and opted for cystectomy with the possible need for a second surgery. The final histopathology report was benign serous cystadenofibroma.

Abdominal Hernia in Equine: Animal Level Risk Factors and Repair Using Polypropylene Mesh

There is a paucity of information regarding the frequency and risk factors associated with the occurrence of an abdominal hernia in different equine species especially donkeys, and mules. In addition, the effectiveness of using polypropylene mesh for the surgical management of abdominal hernia in donkeys and mules is still unknown. The purpose of the present study was to evaluate the efficacy of using polypropylene mesh for the surgical treatment of abdominal hernia in horses, donkeys, and mules and to address the occurrence and risk factors associated with an abdominal hernia in the selected animal species. Based on clinical and ultrasound proof of abdominal hernia, 48 animals were included in the current study. A questionnaire was created to imply the assumed risk factors associated with occurence and clinical findings of abdominal hernia. Hernioplasty using polypropylene mesh was used for the surgical treatment. The abdominal hernia was prevalent (P < .05) in foals followed by adult horses, donkeys, and mules (25, 15, 6, and 2), respectively. Ages from 3 to 5 years exhibited more abdominal hernias in donkeys, mules, and horses (12.5%, 4.2%, and 31.3%, P < .05), respectively. In all studied animals, females were more prevalent than males (70.8%, n = 34 vs. 29.2%, n = 14) respectively. The complication of abdominal wall hernia was positively affected by the time to repair admitted cases (P = .000). The majority of the animals (36 cases) recovered without complications, however, 10 cases had mild difficulties such as suture abscess, wound infection, serous fluid accumulation, and hematoma postsurgery. In addition, two cases of postoperative recurrence were documented. The results herein indicated that polypropylene mesh hernioplasty may be an alternative to the treatment of equine abdominal hernia. Recognizing the potential risk factors associated with an abdominal hernia in different equine species may be helpful to construct the best preventive measures.

Heterogeneity of EpCAM-positive cells in low-grade serous ovarian carcinoma ascitic fluid: a clinical case

Ovarian cancer is one of the most malignant and aggressive tumors of the female reproductive system. Late diagnosis is one of the most significant problems: more than two-thirds of cases are detected only at stage III–IV. Ovarian cancer is characterized by a unique metastatic process. Implantation is the earliest and most common way of metastasis. It is often accompanied by fluid accumulation in the abdominal cavity, known as ascites. We report a case of low-grade serous ovarian carcinoma with a large heterogeneity of tumor cells in the ascitic fluid detected using multicolor flow cytometry. We demonstrated the advantages and benefits of this method in the diagnosis of ovarian cancer. Multicolor flow cytometry opens new horizons for liquid biopsy in oncology.

Characterization of surface markers on extracellular vesicles isolated from lymphatic exudate from patients with breast cancer

BackgroundBreast cancer is the most common cancer, and the leading cause of cancer-related deaths, among females world-wide. Recent research suggests that extracellular vesicles (EVs) play a major role in the development of breast cancer metastasis. Axillary lymph node dissection (ALND) is a procedure in patients with known lymph node metastases, and after surgery large amounts of serous fluid are produced from the axilla. The overall aim was to isolate and characterize EVs from axillary serous fluid, and more specifically to determine if potential breast cancer biomarkers could be identified.MethodsLymphatic drain fluid was collected from 7 patients with breast cancer the day after ALND. EVs were isolated using size exclusion chromatography, quantified and detected by nanoparticle tracking analysis, electron microscopy, nano flow cytometry and western blot. The expression of 37 EV surface proteins was evaluated by flow cytometry using the MACSPlex Exosome kit.ResultsLymphatic drainage exudate retrieved after surgery from all 7 patients contained EVs. The isolated EVs were positive for the typical EV markers CD9, CD63, CD81 and Flotillin-1 while albumin was absent, indicating low contamination from blood proteins. In total, 24 different EV surface proteins were detected. Eleven of those proteins were detected in all patients, including the common EV markers CD9, CD63 and CD81, cancer-related markers CD24, CD29, CD44 and CD146, platelet markers CD41b, CD42a and CD62p as well as HLA-DR/DP/DQ. Furthermore, CD29 and CD146 were enriched in Her2+ patients compared to patients with Her2- tumors.ConclusionsLymphatic drainage exudate retrieved from breast cancer patients after surgery contains EVs that can be isolated using SEC isolation. The EVs have several cancer-related markers including CD24, CD29, CD44 and CD146, proteins of potential interest as biomarkers as well as to increase the understanding of the mechanisms of cancer biology.

Cytology of body cavity fluids- established methods and new developments

Body cavity fluids are among the most frequently examined samples in cytology. Cytomorphology is supplemented by additive testing. An international system of terminology and classification has been recently presented. Cytopreparation and staining techniques as well as some exemplary morphological patterns are presented. "The International System for Serous Fluid Cytopathology" (TIS) is briefly presented. Pleural effusion, pericardial effusion, and ascites: special technical issues, immunocytochemistry, molecular diagnostics, and reporting system issues are discussed. Body cavity fluids are important samples that provide significant information. Additive testing is established for routine use. The form and structure of reports is widely divergent in practical use. Areporting system for serous fluid cytopathology that is easily applied and recognized internationally is highly desirable. TIS is avaluable approach to this goal.

The First Mouse Model of Meckel's Diverticulum Carcinoma.

Cancer of the Meckel's diverticulum (MD) is extremely rare. It is often advanced at the time of operation and the prognosis is poor. An effective treatment for this cancer has not yet been developed and there is no MD-carcinoma mouse model. MD carcinoma was established as a patient-derived xenograft (PDX) in 5-week-old male nude mice by subcutaneous transplantation of surgical specimens together with surrounding normal tissue. Hematoxylin and eosin (H&E) staining was performed on paraffin-embedded tissue sections of the original tumor resected from patients and transplanted tumors grown in nude mice. Three of five mice implanted with MD tumor fragments grew. MD-carcinoma histopathology, observed with H&E-stained tissue sections of the tumors grown in the mice and tumor from the original patient, was concordant. Both showed the luminal structures characteristic of MD carcinoma, and the lumens were filled with serous fluid. The first PDX mouse model of MD carcinoma has been established. The PDX model maintained MD-carcinoma histology of the tumor in the patient. The MD carcinoma mouse model will enable basic research on MD carcinoma, as well as the testing of novel therapeutic agents.

Diagnosis of Lung Adenocarcinoma with Clear Cell Features in Pleural Effusion: Cytomorphologic Features, Immunocytochemical Studies, and Differential Diagnosis.

Clear cell adenocarcinoma (CCA) of the lungs is no longer referred to as a subtype in recent classifications of lung adenocarcinoma. Like signet ring features, clear cell features are regarded as cytological features rather than histological subtypes. Additionally, in serous fluids, adenocarcinoma metastasis with clear cell features is a diagnostic challenging entity due to other tumors that come to mindfirst during the differential diagnosis. Here we report a case, diagnosed as CCA of lung metastasis in pleural fluid and evaluated its differential diagnosis.

Application of the Indian Academy of Cytologists Recommendations for Reporting Serous Fluid Cytopathology in Routine Reporting of Ascitic Fluid Specimen and Assessment of the Risk of Malignancy.

Background:A five-tiered reporting system for effusion fluid cytology has been published by the Indian Academy of Cytologists (IAC). Only a single study has evaluated the applicability of this system in routine reporting.Aims:We intend to evaluate the practical utility of this system in routine reporting of ascitic fluid cytology.Materials And Methods:Nine hundred and sixty-one cases of ascitic fluid cytology were included in this study. The clinical, radiological, cytomorphological, and follow-up data of these cases were reviewed. All cases were recategorized according to the proposed IAC system, and the risk of malignancy (ROM) for each category was estimated.Results:Age of the patients ranged from 1 to 92 years, and fluid volume ranged from 10 ml to 3 l. The number of cases included in each category and their respective ROM were as follows: category 1: 41, 21.42%; category 2: 805, 14.9%; category 3: 5, 33.3%; category 4: 31, 90%; and category 5:79, 96.4%.Conclusions:The new IAC guidelines for the serous fluid is representative, informative, and could be easily applied at our institutional level. We used the recommended diagnostic categories for reclassifying the ascitic fluid samples based on their cytosmear findings and conclude that the system has enormous utility at each level starting from the collection of fluid samples till the delivery of the report.

Intraluminal endoscopy in diagnosis and treatment of fluid collections in acute pancreatitis

To improve treatment outcomes in patients with acute pancreatitis through a differentiated approach to transluminal drainage. There were 1074 patients with acute pancreatitis between January 2018 and December 2021 at the Sklifosovsky Research Institute for Emergency Care. EUS was used as a final diagnostic method to determine localization, dimensions, shape and contours of fluid collections. We also assessed content, presence or absence of a capsule and connection with pancreatic ductal system, possibility of intraluminal drainage under EUS control. A plastic stent with rounded ends was installed if homogeneous hypo- and anechoic cavity with clear even contours was detected. The same measure was applied in case of aspiration of serous or serous-hemorrhagic fluid. The indication for installation of covered self-expanding endoprosthesis was inhomogeneous anechoic fluid collection with hyperechoic inclusions (sequesters) and cloudy purulent content. Patients with necrotic forms underwent insertion of a cystonasal drainage tube 7Fr for sanitation of the cavity with 0.05% aqueous chlorhexidine solution. Endoscopic sequestrectomy was performed every 24-48 hours. Stent was removed in 6 (for encapsulated peripancreatic fluid collections) or 1 month (for other types of fluid collections) after discharge. According to the EUS data, endoscopic TLD was performed in 63 (46%) out of 136 patients with fluid collections. Among 63 patients with TLD, connection with pancreatic ductal system was found in 5 (7.9%) patients. These ones underwent pancreaticoduodenal stenting. Twenty-two patients underwent elective sequestrectomy after stenting of necrotic types of fluid collections with fully covered self-expanding stents. Additional percutaneous drainage was required in 11 (45.8%) of 24 patients. Complicated postoperative period was observed in 4 (6.3%) patients with acute necrotic fluid collections (bleeding from the area of pancreatogenic destruction). Four (6.3%) patients died. Autopsy revealed resolution of purulent-inflammatory process in all patients. Intraluminal surgery is possible not only for homogeneous delimited fluid collections, but also for advanced lesions including infected destructions. This approach allows us to consider endoscopic intraluminal drainage as the final minimally invasive method of surgical treatment of pancreatic necrosis. Its effectiveness is up to 45.8%.

Topical Nepafenac 0.1% or 0.3% for the Treatment of Central Serous Chorioretinopathy: A Case Series of Chronic and Recurrent Disease and Review of the Literature

Central serous chorioretinopathy (CSCR) is a disease involving leakage of serous fluid through the retinal pigment epithelium, resulting in neurosensory retinal detachment. The majority of acute CSCR cases resolve spontaneously. However, treatment options for chronic and recurrent cases are lacking. In this case series, topical nepafenac 0.1% and 0.3% were investigated as novel treatments for chronic and recurrent CSCR. We performed a retrospective case series analysis of six patients diagnosed with chronic recurrent CSCR. Data from patient medical records were collected, including age range, gender, subjective complaints, Snellen visual acuity (VA), clinical eye examination, central macular thickness (CMT) on optical coherence tomography, prior treatments, time of follow-up, and time to resolution of CSCR. The six cases of chronic and recurrent CSCR in this study were treated with 0.1% and/or 0.3% topical nepafenac. The mean age of the six cases was 52 years. There was an average gain in vision of 2.5 lines in Snellen VA, and a final Snellen VA of 20/20 was achieved in each case. The average time to complete resolution of CSCR was 3.33 months. The decrease in CMT ranged from 105 µm to 507 µm, with an average decrease of 240 µm, and subretinal fluid resolved completely in all the six cases.

Importance of Serosal Fluid Cytology as an Aid to Primary Diagnosis: A Descriptive Cross-sectional Study

Introduction: Cytological study of fluids is an inexpensive, simple procedure and has significant utility in diagnosing neoplastic and non neoplastic lesions. The cytological examination of fluids in combination with physical examination helps identify aetiologic agents, follow the natural process of the disease and monitor the response to the treatment. Aim: To determine the diagnostic utility of serosal fluid cytology and analyse the incidence of neoplastic and non neoplastic lesions using serous fluid cytology. Materials and Methods: This was a descriptive cross-sectional study comprising 375 cases conducted in a tertiary care hospital, Sangli, Maharashtra, India, from August to July 2021. Purposive sampling was used to recruit the participants. All the patients with pleural effusions, ascites or in whom Cerebral Spinal Fluid (CSF), pericardial and synovial fluids examination was indicated were included. The provisional diagnosis was obtained from case sheets, including relevant clinical information. Smears were prepared from freshly tapped specimens without adding anticoagulants and were processed by routine, conventional smear technique. The data were analysed using the SPSS version 22.0 for Windows. Numerical variables were reported as frequency and percentage. The chi-square test was used wherever necessary, and the p-value less than 0.05 were considered significant. Results: The peritoneal fluid was the most common fluid collected in the present study, followed by pleural fluid and CSF. The malignancy rate in the present study was 19 (10.4%) of peritoneal fluid, 6 (5.9%) for pleural fluid, and 2 (4.1%) for CSF. Adenocarcinoma was the most common malignancy found in present study. Conclusion: Adenocarcinoma was the most common malignancy found in this study, which was in concordance with the research conducted earlier, where gold standard investigations confirmed the findings. In the peritoneal fluid, most of the patients had cirrhosis and tuberculosis. In pleural fluid and cerebrospinal fluid, most of them had tuberculosis and chronic inflammatory conditions, respectively. Previous researchers confirmed similar findings in their studies. It is seen that malignant and benign conditions like tuberculosis can be diagnosed well with effusion cytology.