الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Bacterial infection is a connnon sequel to wounding Elnd all wounds are liable to infection.. They may become infected, in a variety of condition, with many different bacteria, The pattern of bacteria causing wound infection seems to be changeable during the course of time. In the past decads, in.fections with gram-negative bacteria including ve.rious colilorms were second only to S .aureus Elnd other gre.m-positive. bacterie.,.’” Now, there is a clinical trend that infections caused by gram-negative bacilli, have become more common with the general use of antibiotics which suppress gram-positive flora. However, for .so short term of years the image of pElthogenic bacteria tends to be static; even though, changes in the prevalent bacteria may be observed. The changes are not only in their frequency but also actual genetic alterations, resulting in organisms with new properties, Moreover, hospital strains are usually more sus ceptible to such-chang.e.s than community strains out-side. .lo1.). This may be attributed to the more susceptible individuals, cross-infection rate, selective pressure of €IJltibiotics and possibilities for tr€lJlsfer of genetic material within dense bacterial popul-ation in hospitaJ.s=-. Though, it is il’DP-orta.nt tha-t- surgeons-, bacterio_logists and clinicians be familiar with the pattern €IJld properii”es of bacteria causing wound infect-ions at a given time at a g~en institution. .” This study was performed to predict the pattern of cf1usativ”e agents of pyogenic wound infections in Sana’ a, Yemen Arab Hepublic, wi thspecial reference to S. aureus ,” and~. coli strains as r-e-presentative to gram positive and gram negative org€lJlisms. This study was carried out on 2909 purulent specimens, out of which, 1718 were collected-£x.om infected wounds of out-patients and 1191 were from infected wounds in local hospitals in Sana’ a. These were, Al Thawra hospital(475), Republic hospital (425), Military hospital (201) and Kuwait hospital (90). It was found that: 1) Mixed infection of wounds were representi~g 11.8 out of 2111 wound samples yielded pathogens, while single in fections were representmg 88.2 . , 2) In hospitals of Sana’ a, gram-ne ga-t-ive-bac-teria, _particularly ~’. coli were the most pre’dcmrina-nt organ-isms is,o lated from wound infections the-re~a-nd the pattern of bacteria causing such’ infections. cons-is-t-.:tng of E. _coli (35.9 ), S.aureus (25.4), Pseudomonas (14.5 ) ,proteus species (6.7 )-, c_oagulase-negative Staph. (4.7 ), St. pyog’enes (4.2 ), Klebsiella (3.3 ~ and all other organisms (5.3 ). 3) In out-patient s, gram-pos i ti ve bacteria part icularly ~. aureus were the most predominant organisms infecting their wounds, the pattern of bact~,J;ia causing such in fections were consisting of S. aureus (5l.5 ), St.M2=. genes (13.4 ), E. coli (12 ), coagulase-negative staph (7.4 ), Proteus species (4.3 ), Pseudomonas species (4 ) and all other organisms (7.4 ). 4) The predominance of gram-negELtive bELcteria in hospital wound infections and the predominance of gram-pos i tive organisms in out-patients wound infections were not changed dur ing the four years of thi,s s_tudy. However a decrease in frequency of E. coli_and other gram-negELtive bacteria coupled wi t.h increase in _frequency of S. aureus . and other gram-posit-ive orgELnisms were observed during the same period. 5) ~. coli strains were the most frequent isolates over all gram-negative bacteria and over all gram-negative Md gram-positive bacteria causing wound infections in hospitals. They comprised the third isolated organism, in out-patients wound infections after S. aureus and st. pyogenes. They represented.also the most frequent isolate-s incriminated in mixed infections of wounds with S. aureus. 6) All O.-groups and serotypes of E. coli could be in criminated in wound infections either in hospitals or out-side. 7) No significant difference in susceptibility to different antibiotics between hosipital and out pati~nt strains of E. Coli. : ..ul . strains were highly susceptible to Nalidixic acid (98.3 ), Nitrofurantoin (93.7 ), polymyxin B (91.9 ), Trimethoprim (44.5 ), Gentamicin (44.1 )” Chloramphenicol (34.4 ) and Ampicillin (28.8) All strains were highly r-esistant to, Penicillin, Gloxa cillin, Erythromycin., Cephalothin, Kanamycin, C1indamycin and Tetracycline. Moreover, 86.5 of resiErta-uce to ampicillin was due to penicillinase production. . 8) §.. aureus strains were the most predominant isolated organisms over all isolates caus ing wound infections in out-patients, they were second infections. to E.coli in hospital They represented the most frequent organism overall grampositive isola-te-s- and ov:eJ:!.all isolates in mixed infections. 9) No certain phage types of S. aureus were responsible for wound infections, and manytPhage types and even non typabIe strains could be incriminated in such infections either in hospitals or in out-patients~ 10) There was a significant dif-f’e-~ence between hospital stre.ins of S. aureus and ou:t-,pa,t_~t-s-tra:ins in their . sensitivity to different -a.p,t-ibioJ;ics. ’Ho-s-pital strains were ten sen.s-i,:tive to antib-iotics-.- ,The-y, h-owever were sensitive to, Methicillin (93 ),’ Gentamicin (92 ), Neomycin (86 ), Cloxacillin (85 ), Cephalothin (82 ), Kanamycin (81 ), Erythromycin (1’5 ), Streptomycin (60), &.nd Chloramphenicol (33 ). They were highly resistant to Penicillin, Ampicillin and Tetracycline. Out-patient stre.ins were exhibiting higher sensitivities to the above &.ntibiotics. 11) The resistance to penicillin ana. ampicillin (84.5 ) &.mong ~. aureus strains were due to enzymatic activity Md the production of penicillinase enzyme was a property of mul tiple antibiotic resistant strains. 12) Most of mul tiple Cilltibiotic resistant S. aureus strains were also resistance to one _or more of the heavy metal ions and a highly significant correlation was observed between these’Cl6trains and.resistCillce to mercur ic ions. 13) No correlation between the sex of patient and the ~isk of wound infection while a. strong correlation was observed between the age and the risk of wound infection. Wound infection was more common in older pat ients of ages 50 to 80 years specially in hospitals.