Impaired initial cell reaction in CAPD-related peritonitis

Area of Science:

• Nephrology
• Immunology
• Infectious Diseases

Background:

• Peritonitis is a common complication in continuous ambulatory peritoneal dialysis (CAPD).
• An impaired initial cell reaction (IICR) in peritonitis, characterized by low neutrophil counts, is an unusual presentation.
• Understanding IICR is crucial for diagnosing and managing CAPD peritonitis.

Purpose of the Study:

• To determine the incidence of peritonitis with IICR over a decade.
• To investigate potential explanations for this unusual peritonitis presentation.
• To compare immune responses in IICR versus normal initial cell reaction (NICR) peritonitis.

Main Methods:

• Retrospective review of CAPD patient files from 1984-1993.
• Analysis of cytokine and prostanoid patterns during IICR and NICR peritonitis episodes.
• Comparison of dialysate cell counts and immune characteristics in IICR patients versus controls.

Main Results:

• The incidence of peritonitis with IICR was 6%, often recurring in affected patients.
• Staphylococcus aureus was a more frequent causative agent in IICR peritonitis.
• IICR patients showed lower baseline dialysate cell counts (macrophages, CD4+ lymphocytes) and delayed IL-6/IL-8 responses.
• Tumor necrosis factor-alpha response was normal, but IL-6 and IL-8 peaked later in IICR.

Conclusions:

• Peritonitis can manifest with abdominal pain and absent cloudy dialysate due to IICR.
• This impaired, often delayed, cellular response is linked to a delayed cytokine response, suggesting potential mesothelial cell dysfunction.
• Further research is needed to confirm mesothelial cell involvement despite normal mesothelial cell markers.