Comments on the editorial by Riggio & Ageloni on the ascitic fluid analysis

Abstract

Angeloni et al published a landmark study on the use of Coulter counters in spontaneous bacterial peritonitis (SBP) diagnosis. Riggio and Angeloni have recently published an editorial on the ascitic fluid analysis in diagnosis and monitoring of SBP. Herein, some points of interest are discussed.

Key Words: Peritonitis, Reagent, Dipstick, Paracentesis, Guidelines, Ascites

TO THE EDITOR

I read with great interest the editorial of Riggio & Angeloni on “The ascitic fluid analysis for diagnosis and monitoring of spontaneous bacterial peritonitis”[1]. In 2003, Angeloni et al[2] published the landmark paper, which set a new era in the diagnostic algorithm of spontaneous bacterial peritonitis (SBP), allowing many clinicians and laboratory staff to feel secure in switching from polymorphonuclear (PMN) manual count to the automated one.

I would like to comment on a few points presented in this editorial. First of all, I would appreciate if the authors could clarify the statement on the need for collection of 10 mL ascitic fluid (AF) in ethylenediaminetetraacetic acid (EDTA) containing tube. Universally, most of the EDTA tubes (“purple-top or red-top tubes”, used for blood collection) have a maximum capacity of 2.5-3.0 mL. If Riggio & Angeloni meant the universal containers, it is my understanding that these tubes, except for being sterile, they do not contain any anticoagulant. On top of that, only 1 mL of fluid is enough for most laboratories to do the differential diagnosis. I disagree with the statement that “following hospitalization of any cirrhotic patient with newly diagnosed ascites, a diagnostic paracentesis is advised”. In fact, all cirrhosis with ascites should have diagnostic paracentesis on hospital admission[3].

There are indeed 4 well-disseminated practical guidelines and expert’s consensus reports, but many other national guidelines have been produced as well[4].

Riggio & Angeloni’s comprehensive “Table 2” should list 90 AF samples and not 47 in the study by Wisniewski et al[5], 2123 samples and not 1041 in the study by Nousbaum et al[6], and 78 samples and not 72 in the study by Vanbiervliet et al[7], although three studies have not been included[8-11]. In addition, Castellote et al[12] in a recently published paper argued that the leucocyte reagent strips may have a role in repeated paracentesis and hence management of SBP.