Sporadic culture-negative peritonitis in peritoneal dialysis patients--absence of endotoxin in dialysate.
BACKGROUND
Indiscriminate use of broad-spectrum antibiotics in peritonitis may have either unwanted side effects or contribute to the development of antibiotic resistance. It is tempting to use broad-spectrum antibiotics in cases of culture-negative peritonitis. This study examines whether Gram-negative agents have to be considered in the management of culture-negative peritonitis. Gram-negative agents are manifested by endotoxin easily detected by the Limulus amebocyte lysate (LAL) test.


METHODS
138 episodes of Gram-negative and culture-negative peritonitis have been retrospectively analyzed; episodes of Gram-negative peritonitis were controls. Correlation between LAL and culture results was compared between the two groups. The LAL test was performed using a commercial kit by incubating a mixture of dialysate effluent and LAL reagent at 37 degrees C. Development of a stable solid clot was considered positive.


RESULTS
In controls, 80 out of 117 Gram-negative peritonitis were LAL positive (68%). None of the 21 culture-negative episodes was LAL positive. In 7 recurrences of Gram-negative peritonitis, the LAL test turned from negative to positive but in none of the recurrences of culture-negative peritonitis. The difference in correlation was highly significant.


CONCLUSIONS
Gram-negative organisms do not seem to be involved in sporadic culture-negative peritonitis. In episodes of peritonitis in which bacteriologic cultures stay negative for 48 h, initial coverage of Gram-negative organisms may be dropped.
Hausmann
Michael J
MJ
Department of Nephrology, Soroka Medical Center and Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel. hausmann@bgu.ac.il
Yulzari
Robert
R
Vorobiov
Marina
M
Douvdevani
Amos
A
Zlotnik
Moshe
M
D015169:Colony Count, Microbial / Q000379:methods; D015314:Dialysis Solutions / Q000302:isolation & purification*; D004731:Endotoxins / Q000302:isolation & purification* / Q000502:physiology; D005260:Female; D006090:Gram-Negative Bacteria / Q000254:growth & development / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000592:standards; D010538:Peritonitis / Q000175:diagnosis / Q000382:microbiology* / Q000628:therapy; D012008:Recurrence; D012189:Retrospective Studies; D013997:Time Factors
D015314:Dialysis Solutions; D004731:Endotoxins