Dialysis Effluent. lines and catheters, and wound sites. An attempt was made. to discern those factors which might adversely affect the

Transcription

1 JOURNAL OF CLINICAL MICROBIOLOGY, Dec. 1987, p /87/ $02.00/0 Copyright C 1987, Americn Society for Microbiology Vol. 25, No. 12 Lbortory Indices of Clinicl Peritonitis: Totl Leukocyte Count, Microscopy, nd Microbiologic Culture of Peritonel Dilysis Effluent BONNIE M. MALES" 2t J. JOSEPH WALSHE,3 AND DANIEL AMSTERDAM' 23* Deprtments of Microbiology' nd Medicine,3 School of Medicine, Stte University of New York t Bufflo, Bufflo, New York 14260, nd Division of Clinicl Microbiology nd Immunology, Erie County Lbortory, Erie County Medicl Center, Bufflo, New York Received 4 My 1987/Accepted 11 September 1987 Totl leukocyte count, microscopy, nd conventionl bcteriologic culture (10-ml sediment) of dilysis effluent were ssessed for their bility to detect peritonitis in ptients on peritonel dilysis. A totl of 73 ptients were surveyed over 17-month period. Lbortory findings included n exmintion of 1,774 dilyste smples nd culture results from blood, wounds, indwelling ctheters, nd other specimens. Of 90 peritonitis events, 72 were culture positive. Grm-stined films were positive in no more thn 14% of the dilystes collected during periods of clinicl peritonitis. Fctors which dversely ffected the microscopic or culturl detection of microorgnisms in effluent included the concentrtion of orgnisms in dilyste, ntibiotic therpy, nd growth medium used. Seeding of the peritoneum with orgnisms originting from other sites of infection or coloniztion ws documented, lthough infrequent, yet bcteremi secondry to peritonitis ws not seen. Becuse of the frequent isoltion of microorgnisms from dilystes in the bsence of clinicl peritonitis, culture-positive findings were poor predictor of peritonitis without other evidence of infection. Detection of peritonitis by totl leukocyte count (without differentil count) of dilyste specimens ws dversely ffected by the overlp in cell counts between dilystes collected either during or in the bsence of peritonitis. This ws ttributed in prt to nonspecific increses in dilyste cell count in the bsence of peritonitis nd ws ssocited with intermittent dilysis nd extrperitonel infection. Peritonel dilysis is used s short-term therpy for cute renl filure (19) nd s long-term tretment for end-stge renl disese (15); however, frequent compliction of peritonel dilysis is peritonitis (21, 22, 27, 29). The dignosis nd effective tretment of peritonitis depends upon clinicl evlution of the ptient nd correltion with exmintion of the dilyste. The ltter routinely includes the determintion of totl leukocyte count of the dilyste nd the recovery nd identifiction of microorgnisms from dilysis effluent. Previous investigtions hve demonstrted problems ssocited with the dignosis of peritonitis bsed solely on these prmeters (5, 18, 22). Vrious techniques hve been used to fcilitte the recovery of microorgnisms from dilyste, such s the use of selected broth medi (13, 22, 23, 30), the processing of lrge volumes of dilysis effluent by concentrtion techniques (22, 28) or totl volume (dilysis bg) culture (4), chemicl or physicl disruption of phgocytes in dilyste sediment for recovery of sequestered orgnisms (26), nd provisions for the removl of ntibiotics from the dilyste (28, 30). Dilyste specimens from ptients seen t the Erie County Medicl Center were submitted to the clinicl microbiology lbortory for determintion of totl leukocyte count, microscopic exmintion, nd bcteriologic culture of dilyste sediment (18). The efficcy of ech dilyste prmeter to detect peritonitis ws ssessed mong dilysis ptients ccording to the type of dilysis performed nd the infectious sttus of the ptient (e.g., extrperitonel infections), which included culture results for other specimens, i.e., blood, * Corresponding uthor. t Present ddress: Roche Dignostic Systems, Div. Hoffmnn-L Roche Inc., Nutley, N.J lines nd ctheters, nd wound sites. An ttempt ws mde to discern those fctors which might dversely ffect the bility of ech prmeter to predict peritonitis in peritonel dilysis ptients. We report our findings on the use of totl cell count determintion, microscopy, nd bcteriologic culture of dilysis effluent; we describe those fctors which contribute to bnorml dilyste findings. MATERIALS AND METHODS A totl of 73 ptients on peritonel dilysis were surveyed over 17-month period. They included 13 ptients on temporry dilysis for cute renl filure (5 men nd 8 women, of whom 6 were dibetics), nd 60 ptients on long-term therpy for end-stge renl disese (28 men nd 32 women, of whom 19 were dibetics). Totl time on dilysis ws 551 ptient-months. The dilysis routine consisted of four dilysis exchnges every 24 h (continuous mbultory peritonel dilysis) or intermittent dilysis, which ws performed twice weekly for 20 or 24 h or once week for 40 to 50 h. During tretment for peritonitis, ptients normlly on n intermittent schedule were dilyzed on dily bsis. Definitions. The sttus of ech ptient ws ssessed on the bsis of vrious clinicl nd lbortory findings nd ws ctegorized s follows: clinicl peritonitis (cloudy dilyste with or without bdominl pin, plus or minus rebound tenderness, or diffuse bdominl pin with rebound tenderness), peritonitis event (minimum period encompssing clinicl or lbortory evidence of peritonitis [ reoccurrence of clinicl peritonitis ssocited with recovery of the sme microorgnism or microorgnisms from dilyste represented seprte peritonitis event]), extrperitonel infection (evidence of infection other thn clinicl peritonitis),

2 2368 MALES ET AL. J. CLIN. MICROBIOL. TABLE 1. Lbortory results of 1,774 dilyste specimens collected during this study No. (%) of specimens No. of leukocytes/mm3 Peritonitis Nonperitonitis Totl Culture positive Smer positive Totl Culture positive Smer positive Without ntimicrobil therpy ' [20] 15 (68) 2 (09) 1,028 [89] 110 (11) 7 (<1) [22] 9 (38) 1 (04) 115 [10] 10 (09) 1 (<1) [58] 49 (75) 9 (14) 15 [011 2 (13) 0 Totl (66) 12 (11) 1, (11) 8 (<1) With ntimicrobil therpy ' [59] 23 (10) 1 (<1) 71 [73] 4 (06) [24] 16 (16) 1 (01) 22 [23] 2 (09) [17] 37 (53) 5 (07) 4 [ Totl (19) 7 (02) 97 6 (06) 0 Vlues in brckets indicte the percent distribution within cell count rnge. nd no infection (no evidence of clinicl peritonitis or other infection). Specimen collection nd processing. A totl of 1,959 dilyste smples were collected from ptients during the 17- month survey period s prt of routine monitoring or during periods of suspected peritonitis. Totl leukocyte counts nd culture results were vilble from 1,774 of the 1,959 dilystes. These 1,774 specimens were included in the present evlution. At lest 10 ml of dilyste ws received by the lbortory. A smple ws removed for determintion of totl leukocyte count with hemcytometer. The remining fluid ws hndled s previously described (18). The dilyste ws centrifuged, nd the sediment ws used for grm-stined film nd inocultion of the following medi: chocolte nd 5% sheep blood tryptic soy gr (Scott Lbortories, Inc., Fiskeville, R.I.), McConkey gr, thioglycolte broth, nd 5% humn blood gr contining vitmin K, yest extrct, nd hemin for nerobic growth, which were prepred inhouse. Additionl informtion ws obtined from other sources nd specimens submitted for culture. These included indwelling venous nd other ctheters (in thioglycolte broth), blood (rdiometric detection of bcteril growth in erobic, hypertonic, nd nerobic blood culture medi; BACTEC [Johnston Lbortories, Inc., Towson, Md.]), nd wounds, including peritonel ctheter (exit-tunnel) site swb smples (microscopy nd bcteriologic culture done s for dilysis effluent; with inclusion of phenylethyl lcohol blood gr [Scott Lbortories, Inc.]). All cultures were incubted nd exmined dily for 7 dys. Identifiction of isoltes ws determined by stndrd methods. Dilyste isoltes. Orgnisms recovered from dilysis effluent were ctegorized s peritonitis relted (isoltes recovered from dilyste during clinicl peritonitis or isoltes recovered from dilyste just before or immeditely fter peritonitis nd identicl to orgnisms recovered from dilyste during peritonitis) or peritonitis unrelted (orgnisms recovered from dilyste, not ssocited with clinicl peritonitis, with or without concomitnt recovery from other body sites or indwelling lines nd ctheters). Sttisticl nlyses. When pproprite, dt were nlyzed by chi-squre nlysis (2). RESULTS During the 17-month period, there were 90 events of clinicl peritonitis. A totl of 72 events were culture positive, of which 71 were bcteril in origin. One event ws ssocited with the recovery of Cndid tropiclis from dilysis effluent. Eighteen of these peritonitis events were culture negtive. Lbortory findings for ll dilyste specimens re summrized in Tble 1. Specimens re listed ccording to the presence or bsence of peritonitis, totl leukocyte count, nd ntimicrobil therpy. No more thn 14% of dilystes collected during clinicl peritonitis were positive by Grm stin. In the bsence of peritonitis, 8 of 1,255 dilystes were smer positive, but only 1 of 8 dilystes yielded orgnisms identicl to those lter recovered during peritonitis. During clinicl peritonitis but before the strt of ntimicrobil therpy, ll culture-positive specimens (73 dilystes) yielded orgnisms relted to the onset of peritonitis (Tble 1). After initition of therpy, some dilystes (7 of 76) yielded orgnisms unrelted to the peritonitis event or to infection or coloniztion of other body sites or indwelling ctheters; the remining 69 isoltes were identicl to orgnisms recovered before the strt of therpy. In the bsence of peritonitis, up to 13% of the specimens were culture positive; this ws relted to the degree of leukocytosis nd ntimicrobil therpy, if ny (Tble 1). The types nd frequencies of orgnisms recovered from dilystes nd their ssocition with peritonitis is depicted in Tble 2. Cogulse-negtive stphylococci (C-NS) were the most prevlent orgnism group recovered from dilystes in TABLE 2. Number nd distribution of microorgnisms recovered from 277 dilyste smples collected during 72 peritonitis events Orgnism type No. of dilystes No. of with isoltes peritonitis events Peritonitis Unrelted relted C-NS S. ureus Alph-streptococci Gmm-enterococci Other streptococci Diphtheroids Diphtheroids (nerobic) Bcillus sp Grm-negtive bcilli Mixed (+ C-NS) Mixed (other) C. tropiclis Grm-positive nd grm-negtive orgnisms.

3 VOL. 25, 1987 EXAMINATION OF PERITONEAL DIALYSIS EFFLUENT 2369 Dilyste isolte TABLE 3. Recovery of peritonitis-relted nd -unrelted microorgnisms from dilyste by conventionl culture Totl no. No. (%) recovered by time (h) of incubtion No. (%) recovered by medium type -48 >48 Thioglycolte blood gr (nerobic) McConkey gr Peritonitis relted (78) 38 (22) 158 (93) 137 (81) 102 (60) 28 (16) Unrelted (50) 53 (50) 86 (36) 38 (36) 21 (20) 5 (05) Totl (88) 175 (63) 123 (44) 33 (12) ech ctegory nd ccounted for 36% (26 of 72) of culturepositive peritonitis events. Stphylococcus ureus ws the second most frequent orgnism ssocited with culturepositive peritonitis (15 of 72 events); they ccounted for the lrgest number (7 of 19) of smer-positive dilystes nd were ssocited with 6 of 10 ctheter site infections seen in our ptients. Of the 10 peritonitis events ttributed to grm-negtive bcilli, Pseudomons eruginos ws the single most frequent grm-negtive bcilli nd ccounted for 3 of the 10 events. Yest (Cndid tropiclis) ccounted for only one cse of culture-positive peritonitis. Recovery of nerobic orgnisms ws limited to diphtheroids. These orgnisms were not ssocited with evidence of clinicl peritonitis or other body sites of infection or coloniztion. The chrcteristics of bcteril recovery by conventionl bcteriologic culture method of estblished efficcy (18) re presented in Tble 3. In ddition, results of blood cultures were ssessed. No bcteril growth ws detected in 63 blood culture sets obtined during 25 peritonitis events. The distribution of dilystes by totl leukocyte count is shown in Tble 1; it includes ll specimens collected from ptients with nd without peritonitis. A more detiled nlysis of totl leukocyte count from specimens collected in the bsence of peritonitis is given in Tble 4. Results for nonperitonitis dilystes collected during or in the bsence of ntimicrobil therpy were not sttisticlly different (P > 0.05) nd were combined. Dilystes re listed by ptient sttus nd dilysis schedule. Selected dilystes collected just before or immeditely fter clinicl peritonitis were defined s preperitonitis nd postperitonitis specimens, respectively, on the bsis of their contining incresed numbers (>100/mm3) of leukocytes, yielding orgnisms identicl TABLE 4. Totl leukocyte count of dilystes without peritonitis No. (%) of dilystes with the Dilyste No. of following no. of leukocytes/mm3 clssifiction dilystes -oe Ptient sttus Preperitonitis (79) 6 (21) 0 Postperitonitis 15 3 (20) 10 (67) 2 (13) Extrperitonel (66) 19 (30) 3 (05) infection No infectionb 1,147 1,031 (90) 102 (09) 14 (01) Dilysis schedule Dily (96) 5 (03) 2 (01) Intermittent' (on) (73)d 81 (24)d 12 (03) Intermittent (mid (97) 16 (03) 0 to off) Compred with vlues for no infection (P < 0.05 by chi-squre nlysis). b These specimens were lso listed by dilysis schedule. c Specimens from ptients on the intermittent dilysis schedule were obtined before or fter dilysis cycle 1, 2, or 3 (on) or mid- or postdilysis (mid to off). d Compred with vlues for dily dilysis (P < 0.05 by chi-squre nlysis). to those recovered from dilystes during peritonitis, or both. A smll number of dilysis effluents ws ssocited with extrperitonel infections, tht is, infections other thn peritonitis. These infections were sometimes ssocited with peripherl leukocytosis nd consisted of the following: cellulitis, 2; pneumoni, 1; meningitis, 1; ctheter exit site infection, 4; ctheter exit site infection with bcteremi (unrelted to dilysis) nd urinry trct infection, 1; gngrene of the foot nd ctheter exit site infection, 1; bdominl wound, 1; nd bcteremi (in the bsence of clinicl peritonitis) with recovery of the sme orgnism from blood nd dilysis effluent, 1. DISCUSSION The types nd frequencies of microorgnisms recovered from dilystes (Tble 2) were consistent with those in previous studies for specimens collected during (14, 22, 29) nd in the bsence of (3, 22) peritonitis. In most instnces, detection of microorgnisms wà bsed on culture findings, since few dilystes were positive by grm-stined film (Tble 1). However, S. ureus ccounted for the lrgest number (7 of 19) smer-positive dilystes. Microscopy is firly insensitive test (5, 13, 18, 22), but it is still useful in those instnces in which the bcteril concentrtion in effluent is high enough (106 CFU/ml) for detection by this method. Microorgnisms re not lwys recovered from dilyste during peritonitis. Up to one-third of reported (1, 8, 14, 22) cses of peritonitis hve been culture negtive. During the 17-month period of this study, culture-negtive peritonitis in our ptients, ccounted for 18 (21%) of 90 peritonitis events seen, which included both cler nd cloudy dilystes by definition. The frequency with which bcteri cn be recovered from peritonel effluents collected from ptients with suspected peritonitis cn vry with the evlution criteri used-cloudy effluent, diffuse bdominl pin, etc. (30). Sterile peritonitis must be differentited from culturenegtive peritonitis. Low ph (20), the presence of endotoxin (12) or chemicl irritnts (16) in dilysis fluid, retrogrde menstrution (8), pseudomembrnous colitis (9), nd eosinophili (25) hve been implicted in sterile peritonitis. Culture-negtive peritonitis is lrgely ttributed (29) to low numbers of orgnisms present in dilyste s result of sequestrtion of bcteri in phgocytes (26). They cn escpe detection by conventionl bcteriologic methods. Culture-negtive peritonitis cn occur if steps re not tken for removl of ntibiotics tht my be present in the effluent (29, 30). Of the 18 events of culture-negtive peritonitis in our ptients, 4 were ssocited with ongoing ntimicrobil therpy initited before specimen collection. Indeed, ntimicrobil therpy hd significnt impct on our recovery of microorgnisms from ll dilystes collected during nd in the bsence of peritonitis (Tble 1) (our culture protocol did not include steps for removl of ntibiotics from the effluent).

4 2370 MALES ET AL. Peritonitis-relted isoltes were more redily recovered on ll medi nd usully required less thn 48 h of incubtion time unlike peritonitis-unrelted isoltes (Tble 3). This pttern of growth ws suggestive of higher colony counts for microorgnisms ssocited with peritonitis, compred with isoltes of the peritonitis-unrelted clss. Differences in bcteril counts between these two clsses of isoltes hve been demonstrted, lthough there my be considerble overlp in numbers (3, 22). Recovery of ll orgnisms from dilystes ws ffected by the growth medium used (Tble 3). Use of n enriched broth medium, such s thioglycolte broth, ws shown to be more effective in recovery of microorgnisms from dilysis effluent thn the use of conventionl plte medi (13). Our results confirmed this finding. On nine occsions, microorgnisms recovered from dilystes of ptients without peritonitis were identicl to orgnisms recovered from other body sites or indwelling ctheters. They were identified s: C-NS, 7; nd mixed cultures with C-NS, 2. The other sites of recovery included: blood, 2; nd peritonel ctheter site, 7. Seeding of the peritoneum by orgnisms originting from other sites my hve occurred in our ptients. Yet there ppered to be no spred of microorgnisms from the infected peritoneum to other res; in those ptients from whom blood cultures were tken, bcteremi secondry to peritonitis ws not seen. Indeed, hemtogenous spred is rre (1, 29). This hs been key feture of dilysis-ssocited peritonitis, which distinguishes it from surgicl peritonitis; in surgicl peritonitis, up to 30% of ptients develop bcteremi (29). Frequent recovery of microorgnisms from dilystes of ptients without peritonitis hs been documented (24). Of 1,255 dilystes collected from our ptients in the bsence of suspected peritonitis, 128 (10%) specimens were culture positive (Tble 1). A mjority of these dilystes yielded orgnisms not ssocited with ny other infection or site of coloniztion. However, 28 of these dilystes were culture positive for pthogens; these included 23 of 29 preperitonitis dilystes nd 5 of 15 postperitonitis dilystes. Like Vites et l. (31), we could frequently distinguish peritonitisssocited isoltes from contminnts by the successive recovery of the former from multiple dilystes collected before the onset of peritonitis. Yet this pttern of recovery ws not lwys seen with these pthogens, nd so distinction between contminnts nd peritonitis-ssocited isoltes could not be redily mde by the lbortory without other evidence of infection. Our results (Tble 1) confirmed previous observtions (3, 5, 7, 22) of n overlp in cell count between dilystes collected either during or in the bsence of peritonitis. This ws ttributed, in prt, to nonspecific increses in cell count tht we observed (Tble 4) in ptients on intermittent dilysis (11) if the effluent ws collected t the strt of dilysis (3). Dilyste leukocytosis hs lso been ssocited with noninfectious conditions, such s eosinophili (13, 25), which hs lredy been discussed. These nonspecific rises in effluent cell count hve been differentited by others (3, 11, 13, 22) from true inflmmtory response to infection by performnce of differentil count. Polymorphonucler leukocytes predominte during peritonitis, wheres in the bsence of infection, the norml cellulr response is monocytic (7, 10). Among dilysis ptients with peritonitis, Hurley et l. (10) observed peripherl leukocytosis only mong ptients with concomitnt, extrperitonel infections, e.g., n infected shunt, pericrditis, or pneumoni. They suggested tht "in- J. CLIN. MICROBIOL. flmmtion of the peritonel cvity is contined loclly without systemic response" in dilysis ptients. Others (6, 22, 29) hve observed low incidence of blood leukocytosis in dilysis ptients with peritonitis. Extrperitonel infection of the exit site, bdominl surgery, ctheter lekge, nd unexplined bdominl pin or diverticulitis hve been ssocited with n incresed number of leukocytes nd n ltered differentil (polymorphonucler?) in dilystes (17). We could demonstrte significnt (P < 0.05) increse in the proportion of dilystes with elevted leukocyte counts from ptients with extrperitonel infections compred with specimens collected in the bsence of infection (no infection) (Tble 4). However, during this study, differentil counts were not routinely performed. These infections were sometimes ssocited with peripherl leukocytosis. Incresed numbers of leukocytes were more chrcteristic of (nd helped to define) pre- nd postperitonitis dilystes (Tble 4), but this ws of little dignostic vlue. Few preperitonitis specimens hd elevted leukocyte counts, nd wheres postperitonitis dilystes often hd incresed cell counts, we could not document tht they were followed by reoccurrence of peritonitis. It is evident tht none of the lbortory tests discussed herein were dequte for detecting peritonitis in dilysis ptients. Detection of microorgnisms in effluent is dependent on the bcteriologic method nd growth medium used. Culture-positive findings re poor predictor of peritonitis becuse of the frequency of microorgnisms in dilystes from ptients without evidence of clinicl peritonitis. Inclusion of totl leukocyte count is useful, but there is no bsolute correltion of dilyste cell count with peritonitis. Nonspecific leukocytosis of the effluent is seen in ptients on intermittent dilysis nd cn rise from the presence of chemicl irritnts or other substnces in dilysis fluid, trum, or extrperitonel infection. Consequently, performnce of differentil count is recommended. Our findings indicted tht other conditions, e.g., extrperitonel infections, dilysis schedule, nd bcteril seeding from other body sites or indwelling ctheters, cn lter the bcteriologic nd cytologicl composition of dilysis fluid. Clerly, our experience indictes tht no one test is dignostic for peritonitis; clinicl symptoms nd signs in conjunction with lbortory dt need to be pplied. The microbiology lbortory should be prepred to mke presumptive determintion of peritonitis bsed on differentil leukocyte count nd Grm stin of the dilyste sediment. Recovery of potentil pthogens from peritonel effluent is dependent on the volume cultured (t lest 10 ml should be used) nd the primry recovery medium used. Bcteremi is rrely ssocited with peritonitis. LITERATURE CITED 1. Atkins, R. C., T. Humphery, N. Thomson, J. Willimson, D. Hooke, nd A. Dvidson Bcteril nd 'sterile' peritonitis, p In R. C. Atkins, N. M. Thomson, nd P. C. Frrell (ed.), Peritonel dilysis. Churchill Livingstone, Ltd., Edinburgh. 2. Colton, T Sttistics in medicine. Little, Brown, & Co., Boston. 3. Cooper, G. L., J. A. White, J. A. D'Eli, P. C. DeGirolmi, C. Arkin, A. Kldny, nd R. Pltt Lck of utility of routine screening tests for erly detection of peritonitis in ptients requiring intermittent peritonel dilysis. Infect. Control 5: Dwson, M. S., A. M. Hrford, B. K. Grner, D. A. Sic, D. M. Lndwehr, nd H. P. Dlton Totl volume culture technique for the isoltion of microorgnisms from continuous mbultory peritonel dilysis ptients with peritonitis. J. Clin.

5 VOL. 25, 1987 EXAMINATION OF PERITONEAL DIALYSIS EFFLUENT 2371 Microbiol. 22: Fenton, P Lbortory dignosis of peritonitis in ptients undergoing continuous mbultory peritonel dilysis. J. Clin. Pthol. 35: Fenton, S., G. Wu, D. Cttrn, A. Wdgymr, nd A. F. Allen Clinicl spects of peritonitis in ptients in CAPD. Peritonel Dil. Bull. l(suppl.): Flnign, M. J., nd R. M. Freemn Cellulr response to peritonitis mong peritonel dilysis ptients. Peritonel Dil. Bull. 4(Suppl.): Grefberg, N., B. G. Dnielson, nd P. Nilsson Peritonitis in ptients on continuous mbultory peritonel dilysis. Scnd. J. Infect. Dis. 16: Hnd, S. P., S. Greer, nd H. D. Tewri Pseudomembrnous colitis nd cloudy peritonel dringe in ptients on peritonel dilysis. Kidney Int. 19: Hurley, R. M., D. Muogbo, G. W. Wilson, nd M. A. M. Ali Cellulr composition of peritonel effluent: response to bcteril peritonitis. Cn. Med. Assoc. J. 117: Joglr, F., M. Tort, R. Burgos, nd V. Mrtinez The leukocyte count nd cute peritonitis in intermittent peritonel dilysis ptients. Excerpt Med. Int. Congr. Ser. 567: Krnicols, S., D. G. Oreopoulos, S. Iztt, A. Shimizu, R. F. Mnning, H. Sepp, G. A. deveber, nd T. Drby Epidemic of septic peritonitis cused by endotoxin during chronic peritonel dilysis. N. Engl. J. Med. 296: Knight, K. R., A. Polk, J. Crump, nd R. Mskell Lbortory dignosis nd orl tretment of CAPD peritonitis. Lncet ii: Krothplli, R., W. B. Duffy, C. Lcke, W. Pyne, H. Ptel, V. Perez, nd H. O. Senekjin Pseudomons peritonitis nd continuous mbultory peritonel dilysis. Arch. Intern. Med. 142: Levey, A. S., nd J. T. Hrrington Continuous peritonel dilysis for chronic renl filure. Medicine (Bltimore) 61: Luce, E., D. Nkgw, J. Lovell, J. Dvis, B. J. Stinebugh, nd W. N. Suki Improvement in the bcteriologic dignosis of peritonitis with the use of blood culture medi. Trns. Am. Soc. Artif. Intern. Orgns 28: Mchel, T., S. Iztt, D. Pntlony, G. Wu, nd D. G. Oreopoulos White cell count nd differentil of predilysis fluid in ptients on chronic intermittent peritonel dilysis. Peritonel Dil. Bull. 4(Suppl.): Mles, B. M., J. J. Wlshe, L. Grringer, D. Koscinski, nd D. Amsterdm Addi-Chek filtrtion, BACTEC, nd 10-ml culture methods for recovery of microorgnisms from dilysis effluent during episodes of peritonitis. J. Clin. Microbiol. 23: Mion, C. M Prcticl use of peritonel dilysis, p In W. Drukker, F. M. Prsons, nd J. F. Mher (ed.), Replcement of renl function by dilysis, 2nd ed. Mrtinus Nijhoff Publishers, The Hgue, The Netherlnds. 20. Oreopoulos, D. G Mintennce peritonel dilysis, p In E. A. Friedmn (ed.), Strtegy in renl filure. John Wiley & Sons, Inc., New York. 21. Peterson, P. K., G. Mtzke, nd W. F. Kene Current concepts in the mngement of ptients undergoing continuous mbultory peritonel dilysis. Rev. Infect. Dis. 9: Rubin, J., W. A. Rogers, H. M. Tylor, E. D. Everett, B. F. Prownt, L. V. Fruto, nd K. D. Nolph Peritonitis during continuous mbultory peritonel dilysis. Ann. Intern. Med. 92: Ryn, S., nd S. Fessi Improved method for recovery of peritonitis-cusing microorgnisms from peritonel dilyste. J. Clin. Microbiol. 25: Slingepeyer, A., C. Mion, E. Despux, C. Perez, J. Dupont, nd A. M. Dnsette Use of bcteriologic filter in the prevention of peritonitis ssocited with peritonel dilysis: long term clinicl results in intermittent nd continuous mbultory peritonel dilysis, p In R. C. Atkins, N. M. Thomson, nd P. C. Frrell (ed.), Peritonel dilysis. Churchill Livingstone, Ltd., Edinburgh. 25. Spinowitz, B. S., R. A. Golden, J. H. Rscoff, nd C. Chrytn Eosinophilic peritonitis. Clin. Exp. Dil. Apheresis 6: Tylor, P. C., L. A. Poole-Wrren, nd R. E. Grundy Incresed microbil yield from continuous mbultory peritonel dilysis peritonitis effluent fter chemicl or physicl disruption of phgocytes. J. Clin. Microbiol. 25: Vmonde, C. A., U. F. Michel, R. A. Metzger, nd K. E. Crroll, Jr Complictions of cute peritonel dilysis. J. Chron. Dis. 28: Vs, S Microbiologicl spects of peritonitis. Peritonel Dil. Bull. 1(Suppl.): Vs, S. I Microbiologicl spects of peritonel dilysis. Kidney Int. 23: Vs, S. I., nd L. Lw Microbiologicl dignosis of peritonitis in ptients on continuous mbultory peritonel dilysis. J. Clin. Microbiol. 21: Vites, N. P., B. A. F. Dle, G. Grice, D. M. Jones, A. J. Rlston, nd P. Ackrill Comprison of methods of erly detection of peritonitis in ptients on chronic mbultory peritonel dilysis. Excerpt Med. Int. Congr. Ser. 567: