Flow cytometric analysis of peritoneal dialysis fluid in suspected peritonitis: diagnostic performance and

Lea Tybirk1, Helle Pilgaard Kristiansen1, Mie Samson1,2

  • 1Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark.

Abstract

Insights

Automated flow cytometry can predict peritonitis culture positivity using white blood cell counts. However, Gram classification in peritoneal dialysis fluid is unreliable with the Sysmex UF-5000.

Area of Science:

  • Nephrology
  • Clinical Diagnostics
  • Microbiology

Background:

  • Peritonitis is a serious complication of peritoneal dialysis (PD), often necessitating broad-spectrum antibiotics.
  • Rapid diagnostics for peritonitis can guide targeted therapy and reduce antibiotic overuse.

Purpose of the Study:

  • To assess the Sysmex UF-5000's diagnostic performance for cell counts and Gram classification in suspected PD-related peritonitis.
  • To evaluate the UF-5000's ability to predict culture positivity and guide antibiotic therapy.

Main Methods:

  • Analysis of peritoneal dialysis fluid (PDF) from adult patients with suspected peritonitis using the Sysmex UF-5000.
  • Comparison of UF-5000 cell and bacterial counts, and Gram classification with culture results.
  • Validation of white blood cell (WBC) counts against the Sysmex XN-9000.

Main Results:

  • 71% of peritonitis episodes were culture-positive.
  • WBC count in UF-5000 urine mode showed moderate accuracy (AUC 0.79) for predicting culture positivity.
  • Gram classification by UF-5000 was unreliable, with high rates of unclassified and misclassified samples.
  • Good agreement for WBC counts between UF-5000 and XN-9000 in body fluid mode, but significant negative bias in UF-5000 urine mode.

Conclusions:

  • WBC count is the most reliable indicator for predicting culture positivity in PD peritonitis.
  • The UF-5000's Gram classification in urine mode is not suitable for PDF analysis.
  • PDF analysis using the UF-5000 or XN-9000 in body fluid mode is recommended.

Related Concept Videos

Peritoneal Dialysis II: Peritoneal Dialysis Systems and Complications01:25

Peritoneal Dialysis II: Peritoneal Dialysis Systems and Complications

Peritoneal dialysis (PD) is a medical process that removes waste products and excess fluid from the body using the peritoneal membrane as a natural filter.Peritoneal Dialysis MethodsSeveral methods can be used for peritoneal dialysis, including Acute Intermittent Peritoneal Dialysis, Continuous Ambulatory Peritoneal Dialysis, and Automated Peritoneal Dialysis, also known as Continuous Cyclic Peritoneal Dialysis.Acute Intermittent Peritoneal Dialysis (AIPD) is used for patients with uremic...
Flow Cytometry01:23

Flow Cytometry

The development of flow cytometry techniques began in 1934 with initial attempts by Andrew Moldavan, a bacteriologist who counted the cells in a flowing capillary system. Moldavan pumped cells through a capillary tube focused under a microscope for visualization. The invention of photometry allowed the measurement of differentially-stained cells, and Louis Kamentsky developed the first multiparameter flow cytometer in 1965 to identify and count the cancer cells in cervical tissue specimens.
In...
Peritoneal Dialysis I: Introduction and Procedure01:30

Peritoneal Dialysis I: Introduction and Procedure

Peritoneal dialysis (PD) is a procedure that facilitates the exchange of solutes, waste products, electrolytes, and excess fluid between the blood in the peritoneal capillaries and a dialysis solution introduced into the peritoneal cavity.Principles of Peritoneal Dialysis (PD)Diffusion: Waste products such as urea and electrolytes move from high concentrations in the blood to low concentrations in the dialysate across the peritoneal membrane. This mechanism is driven by the concentration...
Peritoneal Dialysis III: Nursing Management01:25

Peritoneal Dialysis III: Nursing Management

Peritoneal dialysis, or PD, utilizes the peritoneal membrane as a filter to eliminate excess fluid and waste products. Effective nursing management is essential for ensuring patient safety, preventing complications, and promoting optimal function of the peritoneal dialysis process.Assessment and MonitoringNurses must thoroughly assess the patient before, during, and after each dialysis session. Regular monitoring includes vital signs, daily weight, fluid intake and output, and laboratory values...