Proteus bacteriuria is associated with significant morbidity in spinal cord injury

STUDY DESIGN

Retrospective chart review.

OBJECTIVES

We investigated the morbidity associated with Proteus bacteriuria in a spinal cord injured (SCI) population.

SETTING

Michael E DeBakey Veterans Affairs Medical Center in Houston, Texas, USA.

METHODS

We reviewed the medical records of all veterans with SCI who received care in our medical center during the past 3 years. Proteus bacteriuria was defined as the growth of Proteus species in any urine culture during the study period. Urinary stones were defined as either renal or bladder calculi.

RESULTS

During the study period, 71 of the 501 subjects (14%) had Proteus and 90 (18%) had urinary stones. Twenty-seven percent of the subjects with Proteus had stones, and the association of Proteus with stones was significant (P<0.05). Proteus bacteriuria was likewise associated with complete injury, hospitalization, decubitus ulcers, and history of stones (P<0.001). Subjects using indwelling catheters, either transurethral or suprapubic, were significantly more likely to have Proteus, whereas subjects practising spontaneous voiding and clean intermittent catheterization were significantly less likely to have Proteus. In the 90 patients with stones, Proteus was associated with requiring treatment for stones and having multiple stones (P<0.01). Twenty-five of the 90 patients with stones (28%) required treatment, most often with lithotripsy, and 6 (7%) developed urosepsis.

CONCLUSIONS

In persons with SCI, Proteus was found in subjects with a greater degree of impairment who were more likely to be hospitalized, to have decubiti, and to use indwelling catheters. Bacteriuria with Proteus predicted urologic complications in persons with SCI. STATEMENT OF ETHICS: All applicable institutional and governmental regulations concerning the ethical use of human volunteers were followed during the course of this research.

Proteus penneri

Proteus penneri, formerly P. vulgaris biogroup 1, was recognized as a new species in 1982. This species is associated with clinical processes similar to those involving P. mirabilis and P. vulgaris and expresses similar pathogenic determinants. In clinical samples, P. penneri is mainly isolated from urine (50%), wound and soft tissue exudates (25%), and blood cultures (15%), mostly of nosocomial origin. Although P. penneri is easy to identify, it can be misidentified as P. vulgaris by automatic systems that do not include the indol test result in the identification process. This species has a characteristic susceptibility profile, essentially due to the production of the chromosomal inducible beta-lactamase HugA, which presents a high homology (86%) with CumA from P. vulgaris. HugA is inhibited by clavulanic acid and determines resistance to aminopenicillins and first- and second-generation cephalosporins, including cefuroxime, but does not affect cephamycins or carbapenems, and is inhibited by clavulanic acid. HugA is derepressed due to mutational processes in gene regulators, affecting the activity of cefotaxime and, to a much lesser extent, that of ceftazidime and aztreonam. This phenotype resembles the production of an extended spectrum beta-lactamase. Like other Proteus species, P. penneri is resistant to tetracyclines and should be considered resistant to nitrofurantoin.

Dissemination of Proteus mirabilis isolates harboring CTX-M-14 and CTX-M-3 β-lactamases at 2 hospitals in Taiwan

From February to June 2003, 111 clinical isolates of Proteus mirabilis were mainly isolated from patients with respiratory or urinary tract infections hospitalized at 3 district hospitals (A, B, C) in central Taiwan. Among them, 34 (30.6%) strains, isolated within 2 hospitals (A and B), exhibited nonsusceptibility to cefotaxime with significant reduction of MIC (> or = 3 log2 dilution) by the effect of clavulanic acid, which confirmed the phenotype of extended-spectrum beta-lactamases (ESBLs). These ESBL producers were coresistant to gentamicin, isepamicin, and amikacin, but remained susceptible to ceftazidime (MIC, < or = 0.5 microg/mL) and meropenem (MIC, <0.5 microg/mL). By isoelectric focusing analysis, polymerase chain reaction, and nucleotide sequencing, we detected the presence of CTX-M-14 in 33 strains and CTX-M-3 in 6 strains (5 strains harboring both CTX-M-14 and CTX-M-3 enzymes). These beta-lactamase genes can be successfully transferred by the conjugative plasmid. Molecular epidemiology of the 34 ESBL-producing P. mirabilis strains by pulsed-field gel electrophoresis using SfiI restriction enzyme revealed 9 different genotypes, suggesting epidemic clones with intra- and interhospital spread. In conclusion, the broadly extended clonal spreading of CTX-M-type P. mirabilis was first discovered at the district hospitals in Taiwan.

Extended-Spectrum-^|^beta;-Lactamase-Producing Proteus mirabilis: Laboratory-Based Surveillance in Cooperation with 12 Clinical Laboratories in the Kinki Region of Japan

We studied 247 strains of Proteus mirabilis collected during the 6 months from November 2003 to April 2004 from 12 clinical laboratories in the Kinki region of Japan for the production of extended-spectrum beta-lactamase (ESBL). Eighteen strains (7.3%) showed MICs for cefpodoxime of > or = 2 microg/mL and 13 strains (5.2%) were positive for the double-disk synergy test. Susceptibility depended on genotype. MICs for cefepime, cefozopran, and cefpirome were high (> or = 8 microg/mL), and that for ceftazidime was low (0.12-0.5 microg/mL). Meropenem showed the lowest MIC (< or = 0.03-0.25 microg/mL) of the calbapenems, while other calbapenems showed somewhat higher values (0.5-2 microg/mL). The MIC of tazobactam/piperacillin was also relatively low (< or = 0.25-1 microg/mL). Analysis of the ESBL genotype by the polymerase chain reaction showed that 12 of 13 strains were CTX-M2 types. CTX-M9 was detected in a single laboratory. The clinical background showed 5 strains in urine samples. Twelve of 13 strains were detected in patients with minimal devices use. No symptoms were found in most cases of established syndrome. Analysis of PCR fingerprint profiles of random amplified polymorphic DNA patterns showed that 6 of 7 strains from hospital 1 showed the same pattern, and 5 of 5 strains from hospital 13 showed the same pattern, suggesting the nosocomial spread of P. mirabilis in each hospital.

Proteus mirabilis bloodstream infections: risk factors and treatment outcome related to the expression of extended-spectrum beta-lactamases

Bloodstream infection (BSI) due to Proteus mirabilis strains is a relatively uncommon clinical entity, and its significance has received little attention. This study was initiated to evaluate risk factors and treatment outcome of BSI episodes due to P. mirabilis producing extended-spectrum beta-lactamases (ESBLs). Twenty-five BSI episodes caused by P. mirabilis occurred at our hospital (Ospedale di Circolo e Fondazione Macchi, Varese, Italy) over a 7.5-year period. Phenotypic and molecular methods were used to assess ESBL production. Clinical records of BSI patients were examined retrospectively. Demographic data, underlying diseases (according to McCabe and Jackson classification and Charlson weighted index), risk factors, and treatment outcome were investigated by comparing cases due to ESBL-positive strains to cases due to ESBL-negative strains. Eleven isolates were found to express ESBLs (TEM-52 or TEM-92). The remaining 14 isolates were ESBL negative and were uniformly susceptible to extended-spectrum cephalosporins and monobactams. Comparison of the two groups showed that previous hospitalization in a nursing home (P = 0.04) and use of bladder catheter (P = 0.01) were significant risk factors for infections due to ESBL-positive strains. In addition, cases due to ESBL-positive strains showed a significantly higher mortality attributable to BSI (P = 0.04). BSI cases due to ESBL-negative isolates uniformly responded to therapy, whereas 5/11 cases due to ESBL-positive isolates failed to respond (P < 0.01). Use of carbapenems was associated with complete response independently of ESBL production. Therapeutic failure and mortality may occur in BSI episodes caused by ESBL-positive P. mirabilis isolates. Thus, recognition of ESBL-positive strains appears to be critical for the clinical management of patients with systemic P. mirabilis infections.

[Prevalence and risk factors for bacteriuria in patients with cirrhosis]

Bacterial infections occur frequently in patients with cirrhosis and may worsen the disease outcome. We investigated the prevalence of bacteriuria in 500 consecutive patients with cirrhosis, in different Child-Pugh stages (41.4% A; 40.8% B; 17% C) and analysed the associated risk factors. Most of the cirrhosis cases were virus related; alcohol abuse was recorded in 6.2% of the patients. Bacteriuria was detected in 139 (27.8%) cases: 32.4% were more than 100,000 cfu/ml; 7.9% between 100,000 and 1.000,000 cfu/ml and the remaining cases more than 1000,000 cfu/ml. Escherichia coli was the most frequent isolated agent (84.5%); Proteus spp. strains were detected only in bacteriuria with more than 100,000 cfu/ml. At univariate analysis, female gender, age and presence of diabetes were significantly associated to bacteriuria, while Child-Pugh stage and the presence of hepatocellular carcinoma were not. In a multivariate model, only female gender and diabetes were significantly associated to bacteriuria. These results indicate that advanced cirrhosis was not a risk for bacteriuria, that was associated rather to gender and diabetes, which are common risk factors for bacteriuria in non-cirrhotic patients.

[Enzymatic resistance to beta lactam antibiotics within the genus Proteus and evaluation of Proteus mirabilis phenotypes and genotypes for resistance to third- and fourth-generation cephalosporins]

INTRODUCTION

The aim of this study was to evaluate betalactam resistance within the genus Proteus and characterize the betalactamases responsible for this resistance.

METHODS

We analyzed 99 strains (87, P. mirabilis; 10 P. vulgaris, and 2, P. penneri) isolated from patients at one University Hospital. Antibiotic susceptibility tests were performed according to NCCLS recommendations. Presence of extended spectrum betalactamases (ESBL) was inferred by both double disk diffusion tests and minimum inhibitory concentration (MIC) of third and fourth generation cephalosporins alone and in the presence of clavulanic acid. Isoelectric points (pI) of the enzymes were estimated by isoelectrofocusing and the presence of the encoding genes was confirmed by polymerase chain reaction (PCR).

RESULTS

A broad spectrum betalactamase could be detected in those isolates (28%) resistant to penicillin and first generation cephalosporins while CTX-M-2 enzyme could be detected in P. mirabilis isolates resistant to third and fourth generation cephalosporins (18%). One of the P. vulgaris displayed reduced susceptibility to cefotaxime due to an enzyme of pI 7.4, while resistance to cefotaxime in one P. penneri was related to an enzyme of pI 6.8. Both enzymes were active on cefotaxime (1,000 mg/l) in the iodometric assay.

CONCLUSION

The broad extended spectrum betalactamase within genus Proteus was TEM-1, while CTX-M-2 was the ESBL responsible for the third and fourth generation cephalosporins in P. mirabilis. In P. vulgaris and P. penneri this resistance was associated with the hyperproduction of the chromosomal encoded betalactamase.

Molecular diversity of Proteus mirabilis isolates producing extended-spectrum β-lactamases in a French university hospital

Between February 1997 and December 2002, 3340 hospitalised patients yielded samples positive for Proteus mirabilis, of whom 45 (1.3%) were colonised/infected by P. mirabilis producing extended-spectrum beta-lactamases (ESBLs). The gross incidence of patients colonised/infected by ESBL-producing P. mirabilis was 1.61/10(5) days of hospitalisation, with 20% of isolates being collected from patients in urology wards, most frequently (53.3%) from urine samples. Seventeen (37.7%) of the 43 isolates were obtained from samples collected within 48 h of hospitalisation, indicating that they were community-acquired. Isoelectric focusing assays and sequencing identified the TEM-24, TEM-92 and TEM-52 ESBLs. Pulsed-field gel electrophoresis revealed eight pulsotypes (I-VIII), with the two most common pulsotypes, IV and VI, comprising ten (23.3%) and 12 (26.6%) isolates, respectively. These pulsotypes were considered to represent epidemic strains and spread in various wards of the hospital.

Nosocomial outbreak by Proteus mirabilis producing extended-spectrum β-lactamase VEB-1 in a Korean university hospital

OBJECTIVES

To examine the molecular mechanisms involved in the beta-lactam resistance of multidrug-resistant Proteus mirabilis isolates that showed an unusual synergy between imipenem and ceftazidime in a Korean hospital.

METHODS

Over an 11 month period, a total of 12 P. mirabilis isolates showing resistance to ampicillin, gentamicin, ceftazidime, cefotaxime, cefuroxime, cefalothin, cefepime, piperacillin, trimethoprim/sulfamethoxazole and ciprofloxacin, were recovered from the sputum and urine specimens of nine patients who were hospitalized in the neurosurgery ward. The extended-spectrum beta-lactamases were screened with a double disc synergy test using ceftazidime, cefotaxime, aztreonam, cefepime and clavulanate. The ESBL types were determined by PCR using specific primers for bla(TEM-1), bla(SHV-1), bla(CTX-M-1), bla(CTX-M-2), bla(CTX-M-8), bla(CTX-M-9), bla(PER-1), bla(GES-1), bla(VEB-1), bla(OXA-10) and bla(OXA-13) followed by sequencing. All the isolates underwent molecular typing by PFGE. The transferability was examined by conjugation.

RESULTS AND CONCLUSIONS

All the isolates showed a marked synergy between the extended-spectrum cephalosporins and clavulanate together with an unusual synergy between cefoxitin and the cephalosporins (cefalothin, cefuroxime, ceftazidime, cefotaxime) and between imipenem, and ceftazidime and cefotaxime. Isoelectric focusing of the crude bacterial extracts showed a beta-lactamase band with a pI value of 5.4, which was inhibited by clavulanate. PCR and sequencing identified the gene to be bla(VEB-1). In addition, the aadB gene was detected, conferring aminoglycoside resistance. The resistance was not transferred by conjugation. The outbreak was of a clonal origin as shown by PFGE demonstrating an identical banding pattern. This is the first report of VEB-1-producing Enterobacteriaceae in Korea.

[Bacterial pathogens, resistance patterns and treatment options in community acquired pediatric urinary tract infection]

BACKGROUND

Epidemiology and resistance patterns of bacterial pathogens in pediatric UTI show large interregional variability and rates of bacterial resistances are changing due to different antibiotic treatment. We intended to evaluate data from northern Germany.

PATIENTS AND METHODS

In 100 children (53 female, 47 male, mean age 4.4 +/- 4.2 years) with community acquired UTI, who presented in the emergency department of our medical school from 2000 - 2002, urine cultures were performed. Inclusion criteria were: acute voiding symptoms, significant bacteriuria with growth of at least 10 (5) colony-forming units/ml urine, leukocyturia > 50/ micro l. Exclusion criteria were underlying renal diseases, anatomic abnormalities of the urinary tract, age < 2 months and recurrent UTI.

RESULTS

Patients presented with a mean rectal temperature of 38.6 +/- 1.3 degrees C, mean CRP of 66 +/- 68 mg/dl, mean WBC 13 500 +/- 5 600/ micro l and mean urinary leukocytes of 425 +/- 363/ micro l. In urine cultures E. coli was found in 47 % of the cases, Enterococcus faecalis 23 %, Proteus mirabilis 8 %, Klebsiella oxytoca 4 %, Pseudomonas aeruginosa 5 % and others 13 %. In 76 % one and in 24 % two different bacterial species (60 % Enterococcus faecalis) were cultured. Mean resistance rates were in all bacteria (in E. coli): Ampicillin 53 % (69 %), Ampicillin and Sulbactam 51 % (61 %), Cefalosporin 1 (st) generation (Cefaclor) 48 % (24 %), Cefalosporin 2 (nd) generation (Cefuroxim) 40 % (3 %), Cefalosporin 3 (rd) generation (Cefuroxim) 33 % (0 %), Tobramycin 30 % (2 %), Ciprofloxacine 0 %, Cotrimoxazole 40 % (42 %), Nitrofurantoin 12 % (0 %).

CONCLUSION

The resistance rates to Ampicillin (+/- Sulbactam) did not increase as compared to previous analyses (1990 - 1995), however, resistance rates to Cotrimoxazole and 1 (st) generation Cefalosporines increased about 20 %. We conclude that the policies for treatment of UTI in children should be re-evaluated every 5 years according to local resistance rates.

Nosocomial outbreak of infections by Proteus mirabilis that produces extended-spectrum CTX-M-2 type beta-lactamase

Nineteen multidrug-resistant Proteus mirabilis strains were isolated from 19 patients suffering from infections probably caused by P. mirabilis. These strains were recovered from urine or other urogenital specimens of 16 inpatients and three outpatients with a hospitalization history in a urology ward of Funabashi Medical Center, from July 2001 to August 2002. These strains demonstrated resistance to cefotaxime, ceftriaxone, cefpodoxime, and aztreonam, while they were highly susceptible to ceftazidime (MIC, </=0.5 micro g/ml). The resistance level of these strains to cefotaxime was decreased by the presence of clavulanic acid. Therefore, the strains were speculated to produce extended-spectrum class A beta-lactamases. These strains were later found to carry bla(CTX-M-2) genes by both PCR and sequencing analyses. The profiles of SmaI-digested genomic DNA of 19 isolates were distinguished into five different clusters by biased sinusoidal field gel electrophoresis. Four of them, consisting of 18 isolates, were suggested to be a clonal expansion. These findings suggested that a nosocomial outbreak of infections by CTX-M-2-producing P. mirabilis had occurred in our medical center. Most patients suffered from urogenital malignancies with long-term catheterization. Cefazolin, cefoperazone-sulbactam, and/or levofloxacin were mostly administered to the patients, but these agents seemed ineffective for eradication of CTX-M-2 producers. Early recognition and rapid identification of colonizing antimicrobial-resistant bacteria, including CTX-M-2-producing P. mirabilis, would be the most effective measures to cope with further spread of this kind of hazardous microorganism in clinical environments.

Molecular epidemiology of Proteus mirabilis infections of the catheterized urinary tract

Proteus mirabilis compromises the care of many patients undergoing long-term indwelling bladder catheterization. It forms crystalline bacterial biofilms in catheters which block the flow of urine, causing either incontinence due to leakage or painful distention of the bladder due to urinary retention. If it is not dealt with, catheter blockage can lead to pyelonephritis and septicemia. We have examined the epidemiology of catheter-associated P. mirabilis infections by use of pulsed-field gel electrophoresis (PFGE) of NotI restriction enzyme digests of bacterial DNA. This technique was shown to be more discriminatory than the classical phenotypic Dienes typing technique. We demonstrated that each of 42 isolates from diverse environmental sources and 10 of 12 isolates from blood, wound swabs, and mid-stream urine samples of hospitalized patients had distinct genotypes. Examination of a set of 55 isolates of P. mirabilis, each from a different clinical or environmental source, identified 49 distinct genotypes and 43 Dienes types. The index of discrimination was 0.993 for the PFGE method and 0.988 for the Dienes method. Applying the PFGE method to isolates from catheter-associated urinary tract infections confirmed that the strains present in the crystalline catheter biofilms were identical to those isolated from the same patient's urine. An analysis of samples taken during a prospective study of infections in catheterized nursing home patients revealed that a single genotype of P. mirabilis can persist in the urinary tract despite many changes of catheter, periods of noncatheterization, and antibiotic therapy.

[Urinary tract infection in institutionalized elderly patients. Incidence of bacterial resistance and risk factors]

INTRODUCTION

The goal of the present work was to study urinary tract infections (UTI) in a sociosanitary center in order to characterize etiology, define sensitivity profiles, and study associations between these profiles and various clinical parameters.

MATERIAL AND METHODS

A prospective study of all urinary tract infections at the caring unit of a geriatric sociosanitary center was carried out. Antibiograms were performed on all patients in which a UTI was suspected, and the association between the isolated organism or E. coli resistance with various clinical parameters (gender, bed confinement, recurrence, incontinence, neural impairment, basic daily life activities and drug use) was studied using a multivariate logistic regression analysis.

RESULTS

Escherichia coli and Proteus mirabilis are the most commonly isolated organisms (51% and 15%, respectively). The former is associated with bed confinement and the female gender. The latter shows an inverse relation with recurrence in 90 days. Resistance to the antibiotics studied correlates with a number of clinical parameters, although associations vary for each antimicrobial agent. Previous use of antibiotics and recurrence of infection have no influence on resistance.

DISCUSSION

Geriatric patients' characteristics may well account for some of the results encountered. However, the development of resistance in the center may be related to spreading from direct contact between patients. The relationship between resistance and drug use may be affected by the external administration, rather than in-center administration, of drugs.

Bacteraemia due to tribe Proteeae: a review of 132 cases during a decade (1991-2000)

To characterize the clinical features of bacteraemia due to tribe Proteeae, 132 cases among 130 patients from 1991 to 2000 were analysed. The organisms included the Proteus species in 63 cases (P. mirabilis in 41, P. penneri in 2 and P. vulgaris in 20), the Providencia species in 8 (P. rettgeri in 3 and P. stuartii 5) and Morganella morganii in 61. Morganella bacteraemia occurred more frequently in the hospital (70.5%). Biliary and hepatic diseases were predominant in cases with Morganella bacteraemia while cardiovascular, urological and neurological diseases were more common in cases with Proteus bacteraemia. Biliary drainage catheters had more frequently been placed in cases with Morganella bacteraemia (39.3%, p < 0.001), and urinary catheters more frequently in cases with Proteus bacteraemia (17.5%). Biliary infection was most common in cases with Morganella bacteraemia (49.2%), while urinary tract infection (UTI) was most common in cases with Proteus bacteraemia (47.6%). Mortality directly related to bacteraemia due to tribe Proteeae was 20.8% (22.6, 50.0 and 15.0% for Proteus, Providencia and Morganella bacteraemia, respectively). In conclusion, Morganella bacteraemia was most frequently associated with biliary infection, while Proteus bacteraemia was most frequently with UTI. Providencia bacteraemia was relatively uncommon and it can be associated with infections other than UTI.

Characterization of CMY-type beta-lactamases in clinical strains of Proteus mirabilis and Klebsiella pneumoniae isolated in four hospitals in the Paris area

We isolated five clinical strains (three Proteus mirabilis and two Klebsiella pneumoniae) with beta-lactam resistance phenotypes consistent with production of an AmpC-type beta-lactamase. The predicted amino acid sequences of the enzymes were typical of class C beta-lactamases. The enzymes were identified as CMY-2, CMY-4 and a new CMY-variant beta-lactamase, CMY-12. The AmpC beta-lactamases from the two K. pneumoniae isolates were found to be encoded on self-transferable plasmids. The genes encoding the AmpC-type beta-lactamase produced by the three P. mirabilis isolates were chromosomal. Four of the five clinical isolates were from patients transferred from Greece, Algeria and Egypt; one of the K. pneumoniae strains was recovered from a French patient. PFGE analysis and rep-PCR fingerprinting showed that the two P. mirabilis isolates from Greek patients were closely related.

Characterization of a new extended-spectrum beta-lactamase (TEM-87) isolated in Proteus mirabilis during an Italian survey

A new natural TEM derivative, named TEM-87, was identified in a Proteus mirabilis isolate from an Italian hospital. Compared to TEM-1, TEM-87 contains the following mutations: E104K, R164C, and M182T. Kinetic analysis of TEM-87 revealed extended-spectrum activity against oxyimino cephalosporins (preferentially ceftazidime) and aztreonam. Expression of blaTEM-87 in Escherichia coli decreased the host susceptibility to these drugs.

Bacterial agents of discharging ears and antimicrobial sensitivity patterns in children in Ibadan, Nigeria

Bacteriological studies were carried out on ear swabs from 361 cases of children with discharging ears at the Microbiology Department of the University College Hospital, Ibadan between March 1995 and February 1997. 308 (85.3%) had positive cultures. 78.6% of these yielded one isolate, 19.2% yielded two isolates while 2.2% had three isolates. Pseudomonas spp. Was the predominant agent of CSOM and ASOM. This was followed by Staphylococcus aureus. Other commonly isolated organisms were Proteus and Klebsiella species. Ofloxacin and ciprofloxacin showed the highest activity to all isolates, while two third of the isolates were sensitive to azithromycin, cefuroxime, ceftriazone and gentimicin.

Pattern of gram negative rods bacteraemia in diabetic patients in Ibadan, Nigeria

In a study of 100 patients in Ibadan between July and December 1995 to evaluate bacteraemia due to gram-negative bacilli, 64% were culture positive, 44 (68.8%) of these yielded gram-negative rods. The isolates were Klebsiella species (43.2%), Escherichia coli (27.3%), Pseudomonas aeruginosa (13.6%), Proteus species (11.4%) and Bacteroides melaninogenious (4.15%) by standard bacteriological methods. Antimicrobial sensitivity results suggested ofloxacin or ceftriaxone with metronidazole as empirical antibiotic therapy.

Clinical relevance of Proteus mirabilis in hospital patients: a two year survey

A retrospective study was performed on 1072 non-duplicate isolates of Proteus mirabilis, taken in the period April 1996 to March 1998, and on 100 patient charts randomly selected during the same period. P. mirabilis isolates accounted for 7.7% of Enterobacteriaceae. The isolates were predominantly from urine (70.2%); of the total, 38.0% were penicillinase-producing isolates, 6.9% were extended-spectrum beta-lactamase (ESBL)-producing isolates and 3.6% produced inhibitor-resistant beta-lactamase (IRB). ESBL-producing isolates were observed in long-stay and intensive care and IRB-producing isolates in paediatric units. Of the 95 patients whose charts were examined, 69 had a confirmed infection, which in 42 cases was nosocomial.

Bacteriology of diabetic foot

OBJECTIVES

To study the relative frequency of bacterial isolates cultured from diabetic foot infections and assess their comparative in vitro susceptibility to the commonly used antibacterial agents.

METHODS

This is a retrospective study with a review of the bacteriology results of specimens taken from 111 consecutive patients with diabetic foot infections at King Abdulaziz University Hospital, Jeddah, Kingdom of Saudi Arabia, during the period January 1997 to June 1999. The specimens were cultured using optimal aerobic and anaerobic microbiologic techniques. Antimicrobial susceptibility testing to different agents, was carried out using the disc diffusion method.

RESULTS

Staphylococcus aureus was the commonest isolate being recovered from 28% of cases, including methicillin resistant staphylococcus aureus in 9 of 30 (30%) patient wounds. The other organisms isolated were Pseudomonas aeruginosa (22%) and Proteus mirabilis (18%), anaerobic gram-negative organisms (11%) mainly Bacteroides fragilis. The antimicrobial susceptibility testing, showed that vancomycin was the most effective against gram-positive and and imipenem was the most effective against gram-negative organisms.

CONCLUSION

Staphylococcus aureus, Pseudomonas aeruginosa, Proteus mirabilis and Bacteroides fragilis were the most common causes of diabetic foot infections. These wounds require use of combined antimicrobial therapy for initial patient management prior to susceptibility results.

The first isolation of Eubacterium suis in Hungary

Eubacterium suis was isolated from the preputium of seven out of 16 mature boars on two farms and from the urinary bladder of one out of five sows originating from a third herd. The morphological and biochemical characteristics of the isolated strains were identical to that of the reference strain of E. suis ATTC 33144. Three out of four strains isolated from Farm A were successfully subcultured aerobically, and then anaerobically again. E. suis together with Proteus mirabilis was isolated from cystitis of a sow 4 days after artificial insemination. These are the first strains of E. suis isolated in Hungary.

[Urinary infection in urolithiasis patients in the Epirus district (northeastern Greece)]

The relationship between renal stones and urinary tract infection is frequent but not well-known. In this study, urinary tract infection was found in 12% of renal stone formers. It is four times more common in females than in males. Urea splitting bacteria (Proteus, Klebsiella, Staphylococcus and Pyocyaneus) lead to stone formation. They were identified in 72% of cases. Proteus was predominant and the organism most frequently found in staghorn stone formers. Other non urea-splitting bacteria (E. coli, Enterobacter, Streptococcus) were observed in 25% to 30% of cases. The percentage of the various bacteria varies according to the degree of resistance to therapy and the patients sex.

Urinary tract infection in adolescent boys

Clinical and laboratory features of 21 adolescent males with urinary tract infections were studied. Sixty-seven percent were symptomatic and 80% revealed abnormalities on initial urinalysis. Forty-eight percent showed structural anomalies of the urinary tract. Recurrences were observed only in those having abnormalities of the urinary tract.