title: Neutrophilic Loculated Tuberculous Pleural Effusion: Incidence, Characteristics and Differentiation From Complicated Parapneumonic Effusion.
abstract: OBJECTIVE
  Tuberculous pleural effusion (TPE) is generally characterized by lymphocytic exudative effusion, either free-flowing or loculated. However, patients can also have neutrophilic loculated TPE, although little data are available concerning the incidence and characteristics of this form of TPE. It is important to differentiate between neutrophilic loculated TPE and complicated parapneumonic effusion (PPE), which also shows neutrophilic loculated effusion but needs a different management approach. The present study evaluated the incidence and characteristics of neutrophilic loculated TPE and differentiated it from complicated PPE.
  
  
  METHODS
  Between 2009 and 2014, a cohort of patients with TPE was retrospectively reviewed in a South Korean referral hospital. Clinical, laboratory, computed tomography and pleural fluid findings of patients with neutrophilic loculated TPE were compared to those of patients with neutrophilic free-flowing TPE and complicated PPE, respectively.
  
  
  RESULTS
  Neutrophilic TPE was observed in 33 (10%) out of 344 patients with TPE. Of these, 10 (30%) patients exhibited loculation of the pleural fluid. These patients showed distinct pleural fluid characteristics. The classical pleural fluid biomarker levels were more intense than those observed in 23 patients with neutrophilic free-flowing TPE, but similar to those of 54 patients with complicated PPE. A high mycobacterial burden was observed in the pleural fluid, and favorable outcomes were achieved with antituberculosis drug administration alone. Nodular parenchymal lesions and pleural fluid adenosine deaminase levels were independent discriminators of neutrophilic loculated TPE and PPE.
  
  
  CONCLUSIONS
  These results may be helpful to understand and manage patients with neutrophilic loculated TPE and differentiate them from patients with complicated PPE.
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: Jaehee
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Radiology, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: Jae Kwang
authors.initials: JK
authors.lastname: Lim
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: So Yeon
authors.initials: SY
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: Seung Soo
authors.initials: SS
authors.lastname: Yoo
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: Shin Yup
authors.initials: SY
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: Seung Ick
authors.initials: SI
authors.lastname: Cha
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: Jae Yong
authors.initials: JY
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Republic of Korea. Electronic address: kimch@knu.ac.kr.
authors.forename: Chang Ho
authors.initials: CH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000378:metabolism; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000382:microbiology / Q000473:pathology*; D010996:Pleural Effusion / Q000453:epidemiology* / Q000382:microbiology; D056910:Republic of Korea / Q000453:epidemiology; D014396:Tuberculosis, Pleural / Q000453:epidemiology* / Q000382:microbiology
chemical_list: D015415:Biomarkers
keywords: Adenosine deaminase; Complicated parapneumonic effusion; Loculation; Neutrophilic tuberculous pleural effusion