Medical Science Publication No. 4, Volume 1
WEDNESDAY AFTERNOON SESSION
21 April 1954
MODERATOR
LIEUTENANT COLONEL EDWINJ. PULASKI, MC
THE BACTERIAL FLORA OF WOUNDS IN THE KOREANWAR*
LIEUTENANT COLONELROBERT B. LINDBERG, MSC
The relation of wound infections to the bacterial population of warwounds has varied extensively during the period from World War I to thepresent. The classic battle problem of gas gangrene was relatively inconspicuousin the Korean war, at least during the major part of the conflict, whichwas fought over a relatively stable front. In the two preceding wars, principalpathogenic species of anaerobes included Clostridium perfringens,novyi, septicum, and histolyticum, while in the Koreanwar only one of these species, C1. perfringens, was present in ahigh percentage of cases. Several conditions of contemporary warfare undoubtedlycontributed to this altered bacteriologic picture. These included the extensiveuse of penicillin and the broad-spectrum antibiotics; rapid evacuationof the wounded; forward location of the Mobile Army Surgical Hospital,with consequent shortened time from wound to definitive treatment; promptand more effective resuscitation; and radical débridement, frequentlywithin 6 hours of wounding. The major part of data on bacteriology of woundsin the Korean war was obtained after the war had passed from its initialfluid phase to the situation of a static front. Hence the cases observedtended to have a more optimal time interval between wounding and treatment,with a consequent reduction in the bacterial population of the wounds ascompared with those incurred during the initial phase of retreat and defenseof the Pusan perimeter, as well as under the circumstances of retreat fromthe Yalu River after the Chinese intervention.
Studies of war wounds in World Wars I and II, including the studiesof Weinberg and Seguin (1), Stock (2), MacLennan (3),and Smith (4), showed presence of a complex bacterial flora, withmultiple species of Clostridia and aerobic organisms typically present.Their reports are chiefly of cases which had progressed to the stage ofwound infection, in contrast to the situation in recent wounds inthe Korean war. Here we were concerned mainly with contamination and earlybacterial proliferation, before clinical evidence of infection
*Presented 21 April1954, to the Course on Recent Advances in Medicine and Surgery, Army MedicalService Graduate School, Walter Reed Army Medical Center, Washington, D.C.
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appeared. Comparable studies of later wounds were made during the courseof evacuation and treatment in Korea and Japan.
This report presents briefly the wound flora of battle injuries at threelevels: first, those seen at the time of débridement at Army SurgicalHospitals, usually within 6 to 8 hours of wounding; second, those seenat the evacuation hospital, 24 to 72 hours post-wounding; and third, thoseseen at the general hospital level in Japan, 4 to 21 days after wounding.The bacteriology of wounds in cases necessitating amputation one week ormore after wounding was also determined. The flora of local soil, clothingand the skin surface of line troops was observed for comparison with theflora of wounds. The aerobic flora of the wounds also was studied, andwill be briefly summarized. Antibiotic sensitivity of Clostridia was determined,and the relationship of this sensitivity to blood and tissue levels ofantibiotics in wounded men was observed.
Observations on Flora of Recent War Wounds
Wounded personnel from the east-central front (Mundung-ni) were studiedduring August and September, 1952, and from December 1952 to February 1953,with cultures of tissue samples collected during débridement atthe 46th MASH.
The object was to determine the extent and nature of wound contaminationduring the first few hours postwounding. Infection was not a major problemat this brief time interval. Specimens were collected, placed in a modifiedRobertson's cooked meat medium,* and shipped to Japan for study. This holdingmedium offered an optimal means for transporting clostridial cultures withmaximum survival of multiple species in a single sample. However, an occasionalseries of tissue samples were found to be negative for Clostridia despitegross contamination. Such results may have been due to undetected variationsin the transport and enrichment medium, and these tissue cultures henceshow fewer Clostridia than were undoubtedly present in the tissues at thetime of debridement.
Principal emphasis was placed on study of wounds of the extremities.The object was to determine the flora present, without losing sight ofthe fact that presence of Clostridia in a wound does not of necessity connoteanaerobic infection. In World War II over 50 percent of wounds were contaminatedwith Clostridia, yet only 1 percent to 2 percent of cases showed any clinicalevidence of clostridial infection (5).
*The classicalformula of an aqueous meat infusion with meat particles added was modifiedby the incorporation of a heart infusion in place of distilled water. pHwas 7.4.
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Findings in the two series of early wound cases were sufficiently disparateto make separate presentation of the results desirable.
During August and September, 1952, 94 tissue samples were collectedfrom 33 patients, of whom 31 (94 percent) yielded Clostridia. Of the 94tissue blocks, Clostridia were recovered from 63 (67 percent); 125 strains,including 19 species, were recovered. The total number of species of Clostridiarecovered per patient was 4. An average of 2 strains of Clostridia wererecovered from each positive tissue block. The average time elapsing betweeninjury and obtaining of tissue sample was 41/2hours. The relative extent of tissue destruction was related tothe extent of clostridial involvement: Artillery wounds were 88 percentpositive and harbored an average 3 species per patient. Mortar and grenadewounds were 65 percent positive for Clostridia and harbored an averageof 6 species per patient. Small arms fire produced wounds of which 55 percentshowed Clostridia with an average of 1.3 species per patient. The incidenceof Clostridia in tissues and in cases of 28 patients of this series isshown in table 1. It will be seen that Cl. sporogenes was the predominantstrain in terms of cases and of tissue samples studied. The principal pathogenicspecies was Cl. perfringens, in 46.4 percent of cases, and
Table 1. Incidence of Clostridia in Tissuesof 28 Patients with Recent Wounds
| Number of cases in which found | Percent of 28 cases positive for Clostridia | Total number of tissues examined in cases positivefor sporogenes | Number of tissues positive of all positive cases | Percent of total tissues positive from positivecases |
Sporogenes | 18 | 64. 2 | 78 | 40 | 51. 2 |
Perfringens | 13 | 46. 4 | 58 | 29 | 50 |
Bifermentans | 10 | 35. 7 | 57 | 16 | 28 |
Novyi | 7 | 25 | 24 | 10 | 41. 6 |
Multifermentans | 7 | 25 | 37 | 11 | 29. 7 |
Paraputrificum | 5 | 17. 8 | 16 | 5 | 31. 2 |
Sordelli | 3 | 10. 7 | 9 | 4 | 44. 4 |
Lentoputrescens | 3 | 10. 7 | 8 | 3 | 37. 5 |
Tertium | 3 | 10. 7 | 6 | 3 | 50 |
Tetanomorphum | 3 | 10. 7 | 15 | 4 | 26. 6 |
Butyricum | 2 | 7. 1 | 7 | 3 | 42. 8 |
Tetani | 2 | 7. 1 | 14 | 3 | 21. 4 |
Aerofoetidum | 2 | 7. 1 | 5 | 2 | 40 |
Carnis | 1 | 3. 9 | 2 | 1 | 50 |
Capitovale | 1 | 3. 9 | 4 | 1 | 25 |
Cochlearium | 1 | 3. 9 | 3 | 1 | 33 |
Putrefaciens | 1 | 3. 9 | 3 | 1 | 33 |
Sphenoides | 1 | 3. 9 | 4 | 1 | 25 |
Histolyticum | 1 | 3. 9 | 2 | 1 | 50 |
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in 50 percent of the tissues. Cl. novyi was present in 25 percentof this brief series of cases. No other pathogenic species appeared inlarge numbers.
Blood cultures taken on 15 severely wounded men yielded an unexpectedlyhigh proportion of anaerobes: 11 were positive, with 4 species and 19 strainsof Clostridia recovered. Although bacteremia due to Clostridia had beenobserved previously, this proportion was deemed unusually high. Subsequentstudies failed to yield a comparable proportion of positives, but 3 outof 30 later cultures on wound cases were also positive for Clostridia.There was no indication that this blood stream invasion was persistent,and it may have been benign. However, it had not been thought that bloodstream involvement was so widespread in war wound cases.
In view of the unexpectedly high proportion of early wounds harboringClostridia and the continuing problem of wound infections observed at thegeneral hospital level, a further study of similar wounds was made underconditions permitting more extensive sampling and a closer liaison betweenthe base laboratory and the MASH. These cultures were taken during Decemberand January, 1952-53. Winter conditions altered the tactical situation:A higher proportion of patients were evacuated by ambulance because ofdecreased flying time available, so that the mean time from wounding totaking of cultures rose to 7.9 hours. Of the 87 patients who were studied,43 showed Clostridia in débrided tissues. This striking drop inincidence of clostridial contamination could not be explained by any specificfactor observed. It is possible that the fact that these patients' extremitieswere inevitably colder during the period between wounding and treatmentmay have retarded bacterial proliferation.
Of the 285 tissue samples cultured from patients who harbored Clostridia,84, or 29 percent, were positive. This lowered proportion of positive tissuesmay well reflect the fact that more extensive sampling was done, so thatsamples of uncontaminated tissue were more frequently included. Among patientsharboring Clostridia, an average of 2.9 species per patient were recovered,and among tissue samples "positive" for Clostridia, 1.5 speciesper sample were recovered.
Table 2 shows the predominant species recovered in the two series ofobservations. Seventeen species were recovered during the summer and 19during the winter study. It will be seen that the predominant species inboth studies was Cl. sporogenes, while the principal pathogenicspecies was C1. perfringens. The incidence of C1. novyi isnoteworthy; 5 to 7 percent of the total strains recovered is less thanone-third the incidence of this potent pathogen observed in other recentwars (3, 4). The minor incidence of C1. septicum in contrastto its
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importance in World War II is also notable. Of the remaining species,only C1. sordelli is generally regarded as pathogenic. (Cl. tetaniwill not be discussed here since it does not fall within the scopeof this study.) Multifermentans, lentoputrescens and paraputrificumwere the other species of principal interest.
Table 2. Clostridia Flora in Two Series ofRecent War Wounds
| Summer 1952 | Winter 1952-53 | ||
Number | Percent of total strains | Number | Percent of total strains | |
Sporogenes | 40 | 29 | 25 | 20. 3 |
Perfringens | 29 | 21. 2 | 22 | 17. 8 |
Bifermentans | 15 | 11 | 3 | 2. 4 |
Sordelli | 4 | 2. 8 | 4 | 3. 2 |
Multifermentans | 11 | 8. 0 | 3 | 2. 4 |
Novyi | 10 | 7. 2 | 7 | 5. 6 |
Paraputrificum | 5 | 3. 6 | 7 | 5. 6 |
Tetanomorphum | 4 | 2. 9 | 2 | 1. 6 |
Butyricum | 3 | 2. 2 | 1 | 0. 8 |
Tertium | 3 | 2. 2 | 3 | 2. 4 |
Lentoputrescens | 3 | 2. 2 | 6 | 4. 8 |
Tetani | 3 | 2. 2 | 4 | 3. 2 |
Carnis | 1 | 0. 7 | 4 | 3. 2 |
Aerofoetidum | 2 | 1. 4 | 2 | 1. 6 |
Histolyticum | 1 | 0. 7 | 0 | 0 |
Cochlearium | 1 | 0. 7 | 2 | 1. 6 |
Putrifaciens | 1 | 0. 7 | 1 | 0. 8 |
Sphenoides | 1 | 0. 7 | 2 | 1. 6 |
Difficile | 0 | 0 | 1 | 0. 8 |
Capitovale | 0 | 0 | 3 | 2. 4 |
Fallax | 0 | 0 | 2 | 1. 6 |
Unclassified and unidentified | 0 | 0 | 19 | 15. 3 |
139 | 123 | |||
Percent of total | Percent of total | |||
Number of patients with Clostridia | 30 | 90 | 43 | 57 |
Number of tissues with Clostridia | 63 | 67 | 84 | 29. 6 |
The flora of the environment, including the skin surface, clothing andsoil of the combat area, was cultured during this investigation to obtainan indication of the actual source of wound contaminations. The skin surfaceharbored, among total strains recovered, 25 percent of C1. sporogenesand 23 percent of Cl. perfringens, with small numbers of bifermentans,novyi and paraputrificum. A total of 17 species
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were found. This pattern most closely resembled that seen in the freshwound. Only 0.7 strain per skin swab was recovered, which proportion mayreflect the difficulties of survival of Clostridia on swabs even in anoptimal environment. Clothing and soil showed an essentially similar population,predominantly Cl. perfringens (32 percent to 37 percent), with 12percent to 20 percent of Cl. sporogenes. This reversed ratio ofpredominant species between wounds and soil, with a closer correspondencebetween skin and wound flora, lends credence to an hypothesis that woundcontamination in this type of warfare is primarily a seeding of tissueswith skin flora, rather than that of soil or clothing. An additional observationbearing on this point is the low incidence of C1. buytyricum inwounds at the MASH level, and its virtual absence in wounds cultured later.It appears that even when soil bacteria are driven into a wound, nonadaptedspecies are promptly eliminated. Of exceptional interest is the fact thatCl. tetani was never recovered from Korean soil, although therewas no difficulty in recovering it from tissues.
Wounds at Evacuation Hospital Level
At the evacuation hospital level data are less available because ofthe difficulties of followup of this extremely mobile population. However,on the basis of 145 cultures identified from wounds at the 11th EvacuationHospital during early 1953, some conclusions may be drawn: The incidenceof Cl. sporogenes and of Cl. perfringens strains remainedapproximately that noted at the MASH. Cl. novyi, relatively infrequentat the MASH level, here made up 13 percent of the strains recovered. Cl.multifermentans also increased in incidence from approximately 6 percentto 12 percent, while Cl. bifermentans decreased in incidence fromapproximately 10 percent to 4 percent. The total of 19 species of Clostridiarecovered included most of those observed throughout the chain of evacuation,although one rare species, Cl. histolyticum, was found twice. Table3 summarizes this information.
Wound Flora in General Hospitals
From Japan most cultures obtained were taken on patients who were notresponding well to treatment. Delayed primary closure of a clean wound,within 6 days of wounding, was the rule, and such wounds, which might haveshown extensive tissue contamination at the MASH, would not usually becultured again prior to closure.
Table 4 shows the results for 1951 and 1952 in specimens submitted forculture from general hospitals. Seventy-four percent of the cases yieldedClostridia, and 67 percent of the tissues cultured were positive.
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Table 3. Flora of Wounds at 11th Evacuation(2 to 4 days average since wounding), January through April 1953
|
|
|
Sporogenes | 39 | 26. 8 |
Perfringens | 22 | 15. 1 |
Multifermentans | 17 | 11. 7 |
Bifermentans | 6 | 4. 1 |
Novyi | 19 | 13. 1 |
Tetani | 4 | 2. 7 |
Sordelli | 1 | 0. 7 |
Carnis | 5 | 3. 4 |
Histolyticum | 2 | 1. 4 |
Lentoputrescens | 5 | 3. 4 |
Capitovale | 2 | 1. 4 |
Paraputrificum | 4 | 2. 7 |
Parabotulinum | 3 | 2. 0 |
Tetanomorphum | 1 | 0. 7 |
Aerofoetidum | 4 | 2. 7 |
Butyricum | 4 | 2. 7 |
Sphenoides | 1 | 0. 7 |
Tertium | 2 | 1. 4 |
Cochleanium | 1 | 0. 7 |
Unidentified | 3 | 2. 0 |
145 |
The predominant species was Cl. perfringens, which appeared morefrequently than it did earlier in the course of wound treatment. Cl.sporogenes was the remaining dominant species. C1. lentoputrescens,a proteolytic nonpathogenic species, was more common than has been observedin other series, while Cl. novyi was seen in only 4.6 percent ofthe total. This important pathogen showed a higher incidence in previouswars. The 23 species identified indicate the diversity of flora present.The unusual observation of Cl. feseri was made; this pathogen hasapparently not previously been observed in human wounds. Another uniquespecies was Cl. difficile, not previously reported in human cases(6).
Table 4. Clostridial Flora of Wounds at GeneralHospitals in Japan, 1951-52
|
|
|
Perfringens | 127 | 36. 3 |
Sporogenes | 76 | 21. 7 |
Multifermentans | 17 | 4. 8 |
Bifermentans | 18 | 7. 3 |
Sordelli | 1 | 0. 4 |
Lentoputrescens | 29 | 12. 3 |
Novyi | 11 | 4. 6 |
Cochlearium | 7 | 2. 9 |
Tertium | 6 | 2. 7 |
Chauvoei (feseri) | 3 | 1. 1 |
Tetani | 7 | 2. 9 |
Paraputrificum | 8 | 2. 9 |
Tetanomorphum | 4 | 1. 6 |
Difficile | 1 | 0. 4 |
Filiforme | 2 | 0. 8 |
Innominatum | 2 | 0. 8 |
Capitovale | 1 | 0. 4 |
Histolyticum | 4 | 1. 6 |
Carnis | 2 | 0. 8 |
Sphenoides | 2 | 0. 8 |
Septicum | 4 | 1. 6 |
Butyricum | 2 | 0. 8 |
Aerofoetidum | 2 | 0. 8 |
Unclassified | 13 | 3. 7 |
349 |
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Bacterial Flora of Amputations
In a series of 41 cases in which amputation was performed at a generalhospital, tissue blocks from the amputated specimen were removed and cultured.The results of clostridial cultures are summarized in table 5. In thesecases the predominant organism was again Cl. sporogenes, with Cl.perfringens observed half as often. This represents a reversal of theratio of these species noted at the general hospital level. Three otherspecies, multifermentans, bifermentans and novyi, were morecommon than they were in the hospital cases. Cl. feseri, which hasbeen regarded as only a pathogen of horses, was recovered here as it wasat the general hospital level.
Table 5. Clostridial Flora of 109 AmputationSpecimens from 41 Cases of Clinical Gangrene due to Wounds, 1952
Organism | Number of strains | Percent of total strains | Number of patients | Percent of total patients |
Perfringens | 18 | 16. 5 | 13 | 31 |
Sporogenes | 38 | 34. 8 | 23 | 56 |
Multifermentans | 14 | 12. 8 | 10 | 24 |
Bifermentans | 10 | 9. 0 | 8 | 19 |
Novyi | 9 | 8. 0 | 9 | 21 |
Lentoputrescens | 4 | 3. 6 | 4 | 9. 7 |
Cochlearium | 3 | 2. 7 | 3 | 7. 3 |
Histolyticum | 2 | 1. 8 | 1 | 2. 5 |
Carnis | 2 | 1. 8 | 2 | 5 |
aerofoetidum | 2 | 1. 8 | 2 | 5 |
Sordelli | 2 | 1. 8 | 2 | 5 |
Chauvoei (feseri) | 1 | 0. 9 | 1 | 2. 5 |
Tetani | 1 | 0. 9 | 1 | 2. 5 |
Pasteurianum | 1 | 0. 9 | 1 | 2. 5 |
Tertium | 1 | 0. 9 | 1 | 2. 5 |
Tetanomorphum | 1 | 0. 9 | 1 | 2. 5 |
|
|
Average number of Clostridia per patient=2.7.
Assay of tissues of 28 patients at amputation was performed for determinationof penicillin level in the muscle and other tissues. Proximal, viable samplesof muscle showed an average of 0.26 unit of penicillin per gram, whilethe more distal samples contained on an averag of 0.22 unit per gram ofmuscle. These levels are about one-fourth of the corresponding blood contentof penicillin in these cases. No specific correlation of antibiotic contentand of clostridial flora was observed in the tissues assayed.
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Aerobic Wound Flora
The aerobic flora of wounds at the various intervals described was determinedin random samples of tissues. Streptococci and Staphylococci comprisedover 50 percent of the total flora at the MASH, with Bacillus strainsnumbering 15 percent of the total. Coliform bacilli were prominent. Theremainder were chiefly Pseudomonas and Proteus forms. Atthe evacuation hospital, a marked rise in the proportion of Proteusand Pseudomonas occurred. When patients reached the general hospital,an increase in the proportiton of Staphylococci appeared and coliform incidencefell. Streptococci were chiefly alpha and non-hemolytic forms, withhemolytic Streptococci occurring more frequently later in the healing process.The vast preponderance of hemolytic Streptococci were group D. Group AStreptococci were particularly infrequent in early wounds.
Sensitivity of Wound Flora to Antibiotics
Sensitivity of wound bacteria to antibiotics was determined on a totalof 520 strains of recently isolated Clostridia. Extreme care in maintainingthe proportion of inoculum to antibiotic dilution was found to be essentialin order to obtain consistent results in sensitivity determinations withthis group.
Table 6 illustrates the sensitivity of the principal species of clostridialflora of wounds. Approximately 85 percent of strains were sensitive topenicillin, aureomycin and terramycin; chloromycetin was relatively lesseffective on most strains. A small but significant proportion of strainswere relatively resistant. This suggests that antibiotic resistance maywell appear with sufficient readiness to constitute a problem in this situation.
When results of antibiotic sensitivity in successive years were studied,it was found that the proportion of Clostridia strains sensitive to penicillinfell from 94 percent in 1952 to 84 percent in 1953. The percentage sensitiveto aureomycin and to terramycin remained constant or rose slightly duringthis time. Among other antibiotics tested, 100 percent of the strains wereinhibited by 20 units of bacitracin.
Penicillin-resistant strains included bifermentans, novyiand sporogenes, among others.
Aureomycin- and terramycin-resistant strains occurred among perfrigens,capitovale, lentoputrescens and sporogenes. Carnis wasparticularly resistant to terramycin. No specific relationship betweenage of wound and resistant strains was noted. In tests on the aerobic flora,the pyogenic cocci tended to be more often resistant to penicillin at alllevels. Aureomycin and terramycin were most often effective
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against the Staphylococci. The hemolytic group D Streptococci were predominantlyresistant to all antibiotics tested. Proteus and Pseudomonaswere largely resistant to all antibiotics tested, while Coliforms weremost effectively inhibited by aureomycin and terramycin.
Table 6. Range of Concentration of Antibioticswhich Inhibit More than 80 percent of Clostridium perfringens, multifermentans,bifermentans, sporogenes and novyi
Clostridium species | |||||
Antibiotic | Perfringens | Multifermentans | Bifermentans | Sporogenes | Novyi |
Terramycin Minimum units inhib. conc | 0. 1-1. 0 | 0. 05-0. 5 | 0. 05-0. 5 | 0. 1-1. 0 | 0. 25-1. 0 |
Number of strains tested | 193 | 45 | 60 | 135 | 7 |
Percent of total inhibited | 88. 7 | 88. 8 | 91. 7 | 89. 6 | 85. 7 |
Aureomycin Minimum units inhib. conc | 0. 05-0. 5 | 0. 05-0. 5 | 0. 05-1. 0 | 0. 1-1. 0 | 0. 1-1. 0 |
Number of strains tested | 189 | 47 | 65 | 132 | 9 |
Percent of total inhibited | 92. 8 | 89. 4 | 90. 8 | 91. 0 | 88. 8 |
Penicillin Minimum units inhib. conc | 0. 1-1. 0 | 0. 05-1. 0 | 0. 05-1. 0 | 0. 1-2. 0 | 0. 05-1. 0 |
Number of strains tested | 184 | 36 | 57 | 132 | 9 |
Percent of total inhibited | 89 | 86. 4 | 94. 7 | 91. 7 | 88. 8 |
Chloromycetin Minimum units inhib. conc | 2. 5-10. 0 | 2. 5-8. 0 | 2. 5-8. 0 | 2. 5-10. 0 | 2. 5-10. 0 |
Number of strains tested | 186 | 43 | 63 | 126 | 8 |
Percent of total inhibited | 81. 5 | 83. 7 | 85. 2 | 90. 0 | 75. 0 |
inhib.=inhibiting.
conc.=concentration.
Summary
A series of observations on war wounds from the MASH level to the generalhospital showed a significantly high degree of contamination of tissueswith a mixed clostridial and aerobic population. The initially predominantspecies was Cl. sporogenes, followed by Cl. perfringens.However, as the patients moved down the chain of evacuation, those woundsstill contaminated to an extent which occasioned culture exhibited a higherand higher proportion of Cl. perfringens, with C1. sporogenessecond in significance. C1. novyi was conspicuously lower in incidencethan has been noted in previous wars, and C1. septicum was virtuallya rarity, in contrast to findings in Europe and North Africa. In specimensfrom amputations, the Clostridia once more showed a lowered incidence ofCl. perfringens, with a predominance of C1. sporogenes andnumerous proteolytic forms present. From 19 to 27 species were collectedat the various levels
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of study. The aerobic flora comprised primarily pyogenic cocci, gram-positivebacilli and coliform bacteria. Group A Streptococci were not encountered.The major part of the aerobic flora was penicillin-resistant, while penicillin,aureomycin and terramycin were inhibitory to the major portion of the clostridialstrains.
References
1. Weinberg, M., and Seguin, P.: La Gangrene Gayeuse.Masson et cie, Paris 1918.
2. Stock, A. H.: Clostridia in Gas Gangrene and LocalAnaerobic Infections during the Italian Campaign. J. Bact. 54: 169,1947.
3. a. Mac Lennan, J. D.: Anaerobic Infections ofWar Wounds in the Middle East. Lancet 245: 63, 1943.
b. Ibid.: Lancet 245: 94, 1943.
c. Ibid.: Lancet 245: 123, 1943.
4. Smith, L. De S.: Clostridia in Gas Gangrene. Bact.Rev. 13: 233, 1949.
5. Lowry, K. F., and Curtis, G. M.: Diagnosis of ClostridialMyositis. Am. J. Surg. 74: 752-757, 1947.
6. Mac Lennan, J. D.: Personal communication, 1954.
