Irrigation-Aspiration for Culturing Draining Decubitus Correlation of Bacteriological Findings with a Clinical Inflammatory Scoring Index

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1 JOURNAL OF CLINICAL MICROBIOLOGY, Nv. 1990, p /90/ $02.00/0 Cpyright 1990, American Sciety fr Micrbilgy Vl. 28, N. 11 Irrigatin-Aspiratin fr Culturing Draining Decubitus Crrelatin f Bacterilgical Findings with a Clinical Inflammatry Scring Index N. JOEL EHRENKRANZ,* BLANCA ALFONSO, AND DEBRA NERENBERG Flrida Cnsrtium fr Infectin Cntrl, 5901 SW 74th Street, Suth Miami, Flrida Received 8 May 1990/Accepted 30 July 1990 Ulcers: Bipsy f infected decubitus ulcers fr culture disrupts tissues and may disseminate infectin. Antimicrbial prphylaxis t prevent disseminatin f infectin may adversely affect bipsy culture results. Irrigatinaspiratin t btain submarginal specimens frm draining decubitus ulcers was studied as an atraumatic, nninvasive culturing technique t serve as an alternative t bipsy in research activities. Tw aspirates were btained serially frm 32 subjects; in 12 subjects, bipsies were als perfrmed immediately. A median f 4.5 bacterial species was recvered per ulcer by irrigatin-aspiratin. Recent antimicrbial treatment had n evident effect n the recvery f bacterial species in general r, specifically, n the recvery f Bacterides species. Cncrdance f results fr bth aspirates was 97.6% fr aerbes and 91.8% fr anaerbes, indicating n interactive methdlgical effect f the first irrigatin-aspiratin n the secnd. Cmpared with bipsy islates fr ne aspirate, the sensitivity was 93% and the specificity was 99.0%; fr anther aspirate, the sensitivity was 94.7% afid the specificity was 99.5%. The psitive predictive value fr either aspirate was.93.9%. A weighted clinical index t scre inflammatry ulcer characteristics was devised (scre range, 0 t 15). In the absence f anaerbes in 15 subjects, the mean scre was 6.1 ± 3.5; in the presence f anaerbes in 17 subjects, the mean scre was 9.4 ± 3.2 (P = 0.008). The presence f aerbic gram-psitive r gram-negative species did nt significantly affect scres. Irrigatin-aspiratin fr culture and clinical scring f inflammatin shuld permit independent serial measures f bacterilgical and clinical curses f draining decubitus ulcers withut patient risk r discmfrt. The generally accepted methd fr culturing draining decubitus ulcers is by bipsy r percutaneus needle aspiratin (11, 16, 20). Natinal authrities use results f needle aspiratin r bipsy cultures f decubitus ulcers in the definitin f decubitus ulcer infectin (8). Hwever, the efficacy f needle aspiratin t btain a specimen fr culture frm the central r leading edges f lesins fund in a variety f inflammatry skin cnditins, including cellulitis cmplicating decubitus ulcers, is cntrversial; needle aspiratin is nt necessarily a reliable methd f recvering pathgenic bacteria (14). Mrever, in the presence f active infectin, an invasive methd f btaining specimens frm decubitus ulcers fr culture is a ptentially dangerus prcedure. Fr an individual with an infected decubitus ulcer, adverse cnsequences f the trauma f surgical bipsy may include direct extensin f infectin. Surgical manipulatin f necrtic ulcers is als regarded as being likely t induce bacteremia; in fact, antimicrbial therapy t prevent endcarditis is recmmended under these circumstances (1). Bacteremia arising frm infected decubitus ulcers is a welldescribed cmplicatin (4, 5, 7, 13). Thus, when dne fr research purpses, bipsy f decubitus ulcers fr culture pses ptential risks and raises imprtant ethical issues. Cnversely, use f antimicrbial prphylaxis t prmte safety may adversely alter bacterilgical findings. A safe, nntraumatic methd fr culturing draining decubitus ulcers t btain a representative sample f bacteria frm infected tissues wuld be highly desirable as an aid t bacterilgical * Crrespnding authr. investigatins f decubitus ulcers. Hence, a study was undertaken t explre the efficacy f recvering bacteria frm beneath the margins f draining decubitus ulcers by a different methd: gentle irrigatin and aspiratin f saline under the ulcer brders, which is an atraumatic nninvasive prcedure. In the present study, the irrigatin-aspiratin technique was cmpared with the surgical bipsy methd fr btaining bacterial cultures f draining decubitus ulcers, t determine the sensitivity, specificity, and predictive values f the new methd. Tw irrigatin-aspiratins were dne sequentially t seek a pssible enhancing interactin f the first prcedure n the secnd. The presence r absence f specific bacterial species was sught in rder t make cmparisns with reprted findings f bipsied ulcers. Since the grwth, survival, and virulence f aerbic and facultative bacterial species in mixed aerbic-anaerbic infectins appear t be prmted by the simultaneus presence f anaerbic bacteria, especially Bacterides species (3, 9, 15, 16), particular attentin was paid t the recvery f anaerbes. T prvide a quantitative clinical descriptin f draining decubitus ulcers fr cmparisn f the extent f ulcer inflammatin with the bacterilgical findings, a scring index was devised. The index was weighted t emphasize manifestatins f inflammatin. Specimens were btained frm subjects living in nursing hmes in the Miami area. Debridements and surgical bipsies were rdered by attending physicians as part f usual patient care activities. A ttal f 30 individuals whse cultures yielded bacterial grwth was sught. 2389

2 2390 EHRENKRANZ ET AL. MATERIALS AND METHODS Subjects: entry criteria. Persns were selected fr irrigatin-aspiratin cultures n the basis f having a draining decubitus ulcer and a willingness t participate in the study. In persns with mre than ne decubitus ulcer, a single ulcer was arbitrarily chsen fr culture, based n its accessibility. N ne frm whm an irrigatin-aspiratin specimen fr culture was btained was excluded frm analysis. Clinical descriptins f ulcers: weighted inflammatry scring index. Ulcers were inspected and clinical findings were recrded at the time f culture and prir t bipsy. Clinical assessments included amunt and character f drainage, extent f cellulitis, presence f ful dr, and presence f any necrsis in ulcer margins r bases. Findings were scred as fllws: drainage n dressing nly, 0; minimal, mderate, and cpius, drainage in ulcer bed, 1, 2, and 4, respectively; serus, sanguinus, sanguin-purulent, and purulent, drainage, 0, 1, 3, and 4, respectively; widest cellulitis width f <1 cm, 21 t <2 cm,.2 t <3 cm,.3 t <4 cm, and.4 cm, 0, 1, 2, 3, and 4, respectively; n ful dr, 0; ful dr, 1; n necrsis, 0; necrsis in ulcer base, 1; necrsis in ulcer margin, 1; and necrsis in bth base and margin, 2. The ttal scre f an individual ulcer was the sum f the scres described abve and ranged frm 0 t 15. Culturing techniques. T btain a specimen frm an ulcer by irrigatin-aspiratin t be used fr culturing, at least 1 ml f sterile 0.085% NaCl withut preservative was aseptically irrigated under the ulcer margin with a needleless 1- r 5-ml sterile syringe. The syringe tip was placed beneath the disrupted skin margin. Gentle irrigatin was dne in fur submarginal sites apprximately 45 degrees apart. Fluid was irrigated t the limit f tissue resistance withut inducing subject discmfrt. Excess fluid was remved with a sterile gauze pad. The ulcer margins were gently massaged circumferentially with a sterile cttn swab. By using a fresh syringe, a secnd irrigatin f at least 1 ml f saline was applied under the ulcer margins as described abve, and the ulcer was again massaged. At least 0.25 ml f fluid was then aspirated and placed int a Prt-A-Cul vial (BBL Micrbilgy Systems) fr aerbic and anaerbic cultures. Specimens were transprted t the labratry fr plating within 2 h. Fr duplicate specimens, the full irrigatin-aspiratin prcedure was repeated in an identical manner between 30 min and 2 h after the first ne. Cultures were prcessed as fllws. Fr aerbic cultures, the aspirate was plated nt the fllwing media: Trypticase sy agar (BBL) with 5% sheep bld, MacCnkey agar, and phenylethyl alchl agar with 5% sheep bld. Fr anaerbic cultures, the aspirate was plated nt CDC anaerbic bld agar, CDC anaerbic kanamycin-vancmycin laked bld agar, and CDC anaerbic bld agar with phenylethyl alchl. In additin, anaerbic specimens were inculated int 8 ml f enriched thiglyclate brth supplemented with vitamin K and hemin. Bipsies were dne at the patient's bedside by an attending surgen. Bipsy specimens were btained n the same day as the aspiratin-irrigatins were dne, immediately after bth aspirates were recvered, and prir t administratin f any antimicrbial drug rdered in cnjunctin with the bipsy. Bipsied tissues were transprted t the labratry in an icebx and plated within 2 h. The tissue specimens were grund with a dispsable tissue grinder, and a representative sample was remved and prcessed fr recvery f aerbic and anaerbic bacteria in the same manner as described abve fr the aspirates. Aerbic culture plates were incubated at 36 C in 5% C02 fr 48 h. The anaerbic medium was placed int an anaerbic GasPak jar (BBL) and incubated at 37 C fr 48 h prir t examinatin. The anaerbic medium was reincubated and bserved thereafter fr a ttal f 7 days. Identificatin and determinatin f aerbic and anaerbic bacteria t the species level were dne by standard techniques (12). Fr aerbic gram-psitive bacteria (AGPB), identificatin was based n cnventinal mrphlgical and bichemical methds, fr aerbic gram-negative bacteria (AGNB) the API 20E system (Analytab Prducts) was used, and fr anaerbes the Minitek Anaerbe II system (BBL) and the API An-Ident system (Analytab Prducts) were used. Susceptibilities f islates t antibitics were determined by the brth micrdilutin susceptibility methd by using standard interpretive criteria fr MICs (10, 19). Frzen micrdilutin trays (Prepared Media Labratries) were used fr susceptibility testing. Bacterial islates characterized t either the species r the genus level were bityped by micrscpic and clnial mrphlgy alng with bichemical and hemlytic reactins. These findings and the antibigrams were used t determine the identities f islates recvered frm the same subject. Pstirrigatin-aspiratin clinical evaluatin. Patients' ulcers were inspected and their medical recrds were reviewed weekly fr a perid f 3 weeks after irrigatin-aspiratin t seek indicatins f new lcal r systemic manifestatins t suggest disseminatin f infectin; indicatins included rders fr new bacterilgical studies r antimicrbial treatments pssibly related t new decubitus ulcer infectin. Data analysis. Student's t test was used fr statistical analysis. T determine the sensitivity f the irrigatinaspiratin methd, the bacterial species recvered in each bipsy specimen were cmpared with thse fund in crrespnding aspirates. T determine specificity, bacterial islates recvered frm bipsy specimens f ther patients but absent frm the bipsy specimen f the patient under study were cmpared with thse in the crrespnding aspirates. RESULTS J. CLIN. MICROBIOL. Characteristics f study subjects. Specimens fr culture were btained frm 32 patients with draining decubitus ulcers. Their mean age was years. There were 9 men and 23 wmen. Sixteen subjects had received n systemic antimicrbial therapy within 4 weeks prir t culture, and 16 had received sme antimicrbial therapy within 24 h befre a specimen fr culture was btained. Nne f the patients had received lcal antibitic therapy during the 24 h befre a specimen fr culture was btained. In nine f the patients wh had received antimicrbial therapy, the drugs included agents capable f inhibiting grwth f Bacterides species (amxicillin-clavulanate, cefxitin, clindamycin, piperacillin, ticarcillin-clavulanate). The extents f the ulcers accrding t a standard anatmic characterizatin (18) were class II-9, class III-16, and class IV-7. The bdy distributins were as fllws: ft (including heel), 9 patients; hip, 11 patients; sacrum, 12 patients. In 5 ulcers drainage was serus, in 3 ulcers it was sanguinus, in 11 ulcers it was sanguin-purulent, and in 13 ulcers it was purulent. In 12 patients bipsies were dne; nne f the patients required preperative antimicrbial prphylaxis fr endcarditis. Characteristics f bacterial islates. Bacteria were recvered in bth aspirates frm 30 patients and in all patients wh had bipsies. In tw subjects, neither aspirate yielded rganisms. Mixed aerbic-anaerbic bacterial flra were

3 VOL. 28, 1990 IRRIGATION-ASPIRATION FOR CULTURING DECUBITUS ULCERS 2391 TABLE 1. Effects f systemic antimicrbial therapy within 24 h prir t culture n recvery f bacteria frm either irrigatin-aspirate N. (%) f subjects Subjects Any N Any N therects AAGNB AAGNB Apy therapy therapy therapy theap terpy Ttal With aerbic islates 15 (93.8) 15 (93.8) With anaerbic islates 9 (56.3) 8 (50) With any Bacterides 4 (44.4) 10 (43.5) islates a AAGNB therapy was antimicrbial drugs that are active against AAGNB, including amxicillin-clavulanate, cefxitin, clindamycin, piperacillin, and ticarcillin-clavulanate. present in 17 patients, and aerbic flra alne were present in 13 patients. The number f individual bacterial species recvered frm an ulcer ranged frm O t 10, with a median f 4.5. Recvery f any bacterial species frm aspirates f either recently treated r untreated patients was similar (Table 1). The frequency f recvery f Bacterides species amng patients wh had r had n received antimicrbial therapy that culd have inhibited these bacteria was als similar. Cncrdance between first and secnd aspirate cultures. Cmparisn f findings f bth aspirates revealed an verall cncrdance f aerbic bacterial species f 83 f 85 (97.6%) islates. Fr grups f AGPB islates there was cncrdance in 46 f 48 (95.8%) aspirate pairs (Table 2). In ne instance each, an entercccal r staphylcccal islate was recvered frm nly ne aspirate. Fr AGNB islates, there was cncrdance in all 37 pairs (100%). Fr anaerbic species, there was an verall cncrdance f 45 f 49 pairs (91.8%). In three instances a peptstreptcccal islate was present in ne aspirate; in ne instance a Bacterides species was present in ne aspirate. Fr anaerbic gram-psitive bacteria (AAGPB) islates there was cncrdance in 27 f 30 (90%) aspirate pairs, and fr anaerbic gram-negative bacteria (AAGNB) islates there was cncrdance in 18 f 19 (94.7%) pairs. Cmparisn f bipsy and irrigatin-aspiratin cultures. Results f bipsy cultures were cmpared with the findings frm bth irrigatin-aspiratin cultures t determine the sensitivity and specificity and the psitive and negative predictive values (Table 3). Fr AGPB in aspirate 1 there was cncrdance f 15 f 19 islates present in bipsy cultures (sensitivity, 78.9%) and cncrdance f 39 f 41 islates absent frm bipsy cultures (specificity, 95.1%). Fr AGPB in aspirate 2, there was cncrdance f 16 f 19 islates present in bipsy cultures (sensitivity, 84.2%) and cncrdance f 40 f 41 AGPB islates absent frm bipsy cultures (specificity, 97.6%) In aspirate 1 ne islate each f crynebacterial, entercccal, and staphylcccal species and Staphylcccus aureus that was recvered in the bipsy cultures f three subjects was absent, and ne islate each f entercccal and staphylcccal species that was nt fund in bipsy cultures f tw subjects was present. In aspirate 2 ne islate each f crynebacterium and entercccal species and S. aureus that was recvered in bipsy cultures f three subjects was absent; these islates were nt present in aspirate 1 frm these same three subjects. In aspirate 2, ne islate f staphylcccal species that was nt recvered in a bipsy specimen was present; fr the individual wh yielded that islate, the islate was als present in aspirate 1. TABLE 2. Distributin f bacterial islates frm bth aspirates f draining decubitus ulcers frm 32 subjects Islate Aerbic bacteria Gram-psitive species Crynebacterium spp. Entercccus spp. Staphylcccus aureus Staphylcccus spp. ther than Staphylcccus aureus Streptcccus grup B Streptcccus grup G Streptcccus nn-b, -D, -G Gram-negative species Achrmbacter xylsxidans Acinetbacter calcaceticus Escherichia cli Klebsiella pneumniae Mrganella mrganii Prteus mirabilis Prvidencia stuartii Pseudmnas aeruginsa Serratia marcescens Anaerbic bacteria Gram-psitive species Clstridium perfringens Eubacterium lentum Lactbacillus jensenii Lactbacillus sp. Peptstreptcccus anaerbius Peptstreptcccus asaccharlyticus Peptstreptcccus magnus Peptstreptcccus micrs Peptstreptcccus spp. Prpinibacterium acnes Staphylcccus saccharlyticus Gram-negative species Bacterides asaccharlyticus Bacterides bivius Bacterides distasnis Bacterides fragilis Bacterides vatus Bacterides thetaitamicrn Bacterides vulgatus Bacterides sp. ther than Bacterides fragilis grup Fusbacterium nucleatum N. f islates recvered Bth aspirates One aspirate il O Fr AGNB there was cmplete cncrdance f bth aspirate cultures fr the 16 islates fund in bipsy cultures (sensitivity, 100%) and the absence f the 48 islates that were nt present in bipsy cultures (specificity, 100%). Fr anaerbes there was cmplete cncrdance f bth aspirate cultures with bipsy cultures fr the 15 AAGPB islates that were present in the bipsy cultures and the 57 AAGPB islates that were absent (sensitivity, 100%; specificity, 100%) and fr the 7 AAGNB islates that were present and the 41 AAGNB islates that were absent (sensitivity, 100%; specificity, 100%). Psitive predictive values were.93.9%

4 2392 EHRENKRANZ ET AL. TABLE 3. Sensitivity, specificity, and predictive values f first and secnd irrigatin-aspiratin cultures f draining decubitus ulcers cmpared with bipsy cultures' N. f islates n bipsy culture First irrigatin- Secnd irrigatin- Islate aspirate culture aspirate culture Present Absent Present Absent Aerbic bacteria Present Absent Anaerbic bacteria Present 2 2 Absent All bacteria Present Absent The sensitivities, specificities, psitive predictive values, and negative predictive values in the first and secnd irrigatin-aspirate cultures were 88.6, 98.2, 93.9, and 96.4% and 91.4, 99.1, 97.0 and 97.3%, respectively, fr aerbic bacteria; 100% fr all calculatins fr anaerbic bacteria; and 93, 99, 96.4, and 98.1% and 94.7, 99.5, 98.2, and 98.6%, respectively, fr all bacteria. b Includes facultative anaerbic species. and negative predictive values were.96.4% fr either aspirate. The results btained frm aspirate 2 were arbitrarily selected fr crrelatin with the weighted clinical scre. Cmparisns f the means f the weighted inflammatry scres f draining ulcers by the presence r absence f varius bacterial grups are given in Table 4. There appeared t be an assciatin between the scre and the presence f anaerbes in the aspirate, as manifested by a significantly greater scre when either AAGPB r AAGNB species were fund. In the absence f either grup f anaerbes, with a ttal pssible scre f 15, the mean scre was ; in the presence f either grup f anaerbes the mean scre was (P = 0.008). The presence f AGPB r AGNB islates, by themselves, did nt appear t influence inflammatry scres significantly. Pstirrigatin-aspiratin culture evaluatin. In the 20 subjects wh were nt surgically treated, the 3-week fllw-up bservatins after irrigatin-aspiratin revealed n clinical, diagnstic, r therapeutic finding t suggest direct extensin f infectin at the ulcer site r the ccurrence f bacteremia. DISCUSSION In this study, a submarginal irrigatin-aspiratin methd t btain aerbic and anaerbic bacteria frm draining decubitus ulcers fr culture prvided bacterilgical results in tw aspirates that were similar t each ther, with 97.6% cncrdance fr the recvery f aerbes and 91.8% cncrdance fr the recvery f anaerbes. These findings did nt indicate that the first irrigatin-aspiratin induced bacterial cntaminatin f the secnd t any great extent r that the bacterial yield in the secnd irrigatin-aspiratin was substantially enhanced because f sme effect f the first. The bacterilgical results f bth irrigatin-aspiratins were cmparable t results f cultures f tissues btained by bipsy frm 12 patients. Fr the first aspirate, by using bipsy cultures as the standard, the verall sensitivity was J. CLIN. MICROBIOL. 93.0% and the specificity was 99.0%; fr the secnd aspirate, the verall sensitivity was 94.7% and the specificity was 99.5%. The psitive predictive value fr either aspirate was.93.9%; the negative predictive value was.96.4%. A different number and variety f bacterial species have been reprted t be present in bipsy cultures f decubitus ulcers as cmpared with swab cultures f the ulcers' surfaces (11, 16). Results f bipsy cultures are generally cnsidered t be mre meaningful than swab culture results, and the frmer have been taken as a standard fr definitin f decubitus ulcer infectin by natinal authrities (8). The ptential risks f bipsy t btain specimens fr culture in the presence f active decubitus ulcer infectin r necrsis and the ptential limitatins f bipsies in serial studies because f ulcer trauma, hwever, have nt been addressed as cncerns by advcates f bipsy culture. In cntrast t bipsy, the irrigatin-aspiratin culture methd caused n tissue disruptin. Furthermre, irrigatin-aspiratin did nt result in any clinical utcmes suggesting disseminatin f infectin. As a nninvasive atraumatic prcedure, this methd has n inherent risk f disseminatin f infectin r causatin f discmfrt and thus is apprpriate fr research purpses. There was 100% sensitivity and 100% specificity fr AGNB species and fr all anaerbic islates fr the irrigatin-aspiratin culture methd in cmparisn with the bipsy findings. Hwever, fr recvery f the AGPB grup f islates, the sensitivities were 78.9% fr aspirate 1 and 84.2% fr aspirate 2; the specificities were 95.1 and 97.6%, respectively. Sme AGPB islates present in an individual's bipsy specimen were absent frm bth aspirate cultures; this may indicate that these AGPB islates were present in such diminished numbers in the periphery f the ulcer that they were nt represented in the submarginal areas. This is cnsnant with the bservatin f variability in culture results btained with bipsy specimens frm f bth peripheral and central areas f the same ulcer (16). On the ther hand, the AGPB islates recvered frm a bipsy specimen but nt fund in bth aspirates may have reflected clniza- TABLE 4. Cmparisns f mean weighted inflammatry index scres f draining decubitus ulcers in relatin t recvery f varius bacterial grups in irrigatin-aspiratin culture Bacterial species N. f Mean + SD decubitus in decubitus decubitus inflammatry index ulcer ulcers scre' AGPB Absent Present ± 3.4 AGNB Absent ± 4.3 Present ± 3.5 AAGPB Absent ± 3.2 Present b AAGNB Absent ± 3.5 Present ± 2.6b Ttal anaerbes Absent ± 3.5 Present ± 3.2b a Weighted inflammatry scre derivatins are defined in the text. b Significance f difference in scres f ulcers when anaerbic bacterial species were absent r present by Student's t test (tw-tail; P < 0.01). Differences f scres f ulcers when aerbic bacterial species were absent r present were nt statistically significant.

5 VOL. 28, 1990 IRRIGATION-ASPIRATION FOR CULTURING DECUBITUS ULCERS 2393 tin islates that were present n the bipsied surface f the ulcer but nt in deeper tissues r the submarginal areas. By the same tken, an AGPB islate fund in bth irrigatinaspirates in ne persn but nt in the bipsy culture may reflect either variability in bacterial distributin in infected tissues r, alternatively, submarginal clnizatin. Systemic antimicrbial therapy within 24 h f btaining the specimens, including treatment that might have inhibited grwth f Bacterides species, did nt appear t diminish recvery f aerbes r anaerbes (Table 1). This is nt necessarily an unexpected finding. In ne study, cefazlin was nt detected in the debrided tissues f decubitus ulcers (2). The clinical implicatins f these findings remain t be explred. The variety and number f islates f individual bacterial species that were present in the aspirate cultures were similar t the variety and number f islates f species reprted in bld cultures f patients with infected decubitus ulcers (4, 5, 7, 13). This indicates that irrigatin-aspiratin cultures yielded the bacterial species with a true ptential fr tissue invasin. A ntewrthy finding f results f invasive methds fr btaining bacterial specimens frm decubitus ulcers fr culture has been the recvery f a wide range f aerbic and anaerbic species (11, 16). As the healing prcess ccurs, there is a prgressive decrease in the number f aerbic and anaerbic species fund in bipsied tissues (16). Thus, the number f islated species is an imprtant cmparisn measure fr irrigatin-aspiratin and invasive methds. The median recvery f 4.5 bacterial species per ulcer fund by irrigatin-aspiratin is in keeping with reprted results f invasive methds, in which means f 4.8 t 5.8 species per bipsied ulcer have been described (16, 17). A scring index, which was weighted t magnify manifestatins f inflammatin, was used t quantify clinical bservatins f inflammatin in the draining ulcers. There was a direct crrelatin with the scre and the presence f anaerbes in aspirate 2, as manifested by a significantly greater scre when anaerbes were present. Recvery f anaerbic islates in a variety f infectins crrelates with an active r enhanced inflammatry prcess (3, 15, 16); as described previusly (16) anaerbes virtually disappear frm decubitus ulcers during the healing prcess. Of a ttal pssible scre f 15, the mean ulcer scre in the absence f anaerbic species was 6.1 ± 3.5; in the presence f anaerbes, the mean scre was 9.4 ± 3.2 (P = 0.008). The presence f either AGPB r AGNB species, by cntrast, did nt appear t influence scres significantly. Hwever, in view f the small number f ulcers that did nt yield AGNB, a type Il errr is pssible. The weighted scring methd ffers a mre precise means by which decubitus ulcer inflammatin may be defined than des the generally used qualitative clinical descriptin. As thers have pinted ut, the micrbilgy f infected decubitus ulcers has nt yet been fully studied (16). The irrigatin-aspiratin culturing methd, alng with the inflammatry scring index, may serve t prvide meaningful serial bservatins in experimental therapeutic studies f bth bacterilgical and clinical findings f draining decubitus ulcers. ACKNOWLEDGMENTS We acknwledge the participatin f residents f the Villa Maria Nursing Center, Jacksn Manr Nursing Hme, Gem Care Nursing Hme, and the Miami Jewish Hme fr the Aged. 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