Antimicrobial profiling and molecular characterization of antibiotic resistant genes of Proteus vulgaris isolated from tertiary care hospital, Islamabad, Pakistan

Urinary tract infections (UTIs) are among the most common bacterial infections acquired from hospitals and community. Pseudomonas and Proteus species are the common cause of these UTIs. Generally, UTIs are self-limiting but have potential to re-occur. Extensive treatment therapy with antibiotics lead to the development of resistance in uropathogens. The development of antibiotic resistance is leading to the failure of currently available antibiotic based therapies thus making the situation worse. The objective of the present study was to access antimicrobial sensitivity and to characterize antibiotic resistant genes of Proteus vulgaris (P. vulgaris) isolated from patients suffering with UTIs. A total of 150 urine samples were collected and cultured on MacConkey agar medium followed by isolation and identification on blood agar medium. Biochemical characterization of all presumptive Proteus isolates was done using Remel Rap ID one kit. Antibiotic sensitivity for P. vulgaris isolates was performed by disc diffusion method. Presence of blaTEM and qnr antibiotic resistant genes was determined by PCR. The results showed that the overall prevalence of P. vulgaris in clinical samples was 11.3%. It showed maximum resistance (94%) to three antibiotics i.e. ampicillin, tigecycline and chloramphenicol, while least resistance was observed against imipenem (12%). Statistical analysis depicted that imipenem had a significantly larger zone of inhibition (P=.01), while ampicillin had significantly smaller zone of inhibition (P=.0004) followed by chloramphenicol (p-value = 0.002). Imipenem should be considered as an effective antibiotic to treat urinary tract infections associated with P. vulgaris. Both blaTEM and qnr genes were found to be involved in conferring resistance to β-lactam and quinolones antibiotics.

Multiple antibiotic-resistant bacteria on fluted pumpkin leaves, a herb of therapeutic value

Fluted pumpkin (Telfairia occidentalis) is a minimally-processed green leafy vegetable traditionally used for its antianaemic properties in the form of leaf juice without a heating or inactivation step before consumption. The aim of the study was to assess the presence of surface microbiota on T. occidentalis leaves and also to determine the antimicrobial susceptibility of isolated organisms. Bacterial contaminants on 50 samples of T. occidentalis leaves were isolated and characterized using standard biochemical methods and the antimicrobial susceptibility of isolated organisms was determined using the antibiotic disc diffusion assay. The results obtained show that the leaves of T. occidentalis is contaminated with organisms which included Enterobacter agglomerans (25.9%), Proteus vulgaris (24.9%), Klebsiella spp. (2.6%), and Serratia liquefaciens (2.1%). Other bacterial isolates recovered in order of frequency included: Staphylococcus spp. (33.7%), Bacillus spp. (8.3%), and Pseudomonas fluorescens (2.6%). Of the 193 bacterial isolates from the leaves of T. occidentalis samples tested for antimicrobial resistance, all (100%) were found to be resistant to ampicillin, cloxacillin, augmentin, erythromycin, and tetracycline while 96% of the isolates were resistant to cephalothin. Resistance to trimethoprim (93%) and gentamicin (83%) was also observed. Approximately, 22% of the isolates were resistant to ciprofloxacin; however, only 11 (5.8%) were resistant to ofloxacin. Thus, uncooked T. occidentalis is a potential source of highly-resistant epiphytic bacteria which could be opportunistic pathogens in consumers.

Characterization of bacteria in ballast water using MALDI-TOF mass spectrometry

To evaluate a rapid and cost-effective method for monitoring bacteria in ballast water, several marine bacterial isolates were characterized by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Since International Maritime Organization (IMO) regulations are concerned with the unintended transportation of pathogenic bacteria through ballast water, emphasis was placed on detecting species of Vibrio, enterococci and coliforms. Seawater samples collected from the North Sea were incubated in steel ballast tanks and the presence of potentially harmful species of Pseudomonas was also investigated. At the genus-level, the identification of thirty six isolates using MALDI-TOF MS produced similar results to those obtained by 16S rRNA gene sequencing. No pathogenic species were detected either by 16S rRNA gene analysis or by MALDI-TOF MS except for the opportunistically pathogenic bacterium Pseudomonas aeruginosa. In addition, in house software that calculated the correlation coefficient values (CCV) of the mass spectral raw data and their variation was developed and used to allow the rapid and efficient identification of marine bacteria in ballast water for the first time.

Production of volatile aroma compounds by bacterial strains isolated from different surface-ripened French cheeses

Twelve bacterial strains belonging to eight taxonomic groups: Brevibacterium linens, Microbacterium foliorum, Arthrobacter arilaitensis, Staphylococcus cohnii, Staphylococcus equorum, Brachybacterium sp., Proteus vulgaris and Psychrobacter sp., isolated from different surface-ripened French cheeses, were investigated for their abilities to generate volatile aroma compounds. Out of 104 volatile compounds, 54 volatile compounds (identified using dynamic headspace technique coupled with gas chromatography-mass spectrometry [GC-MS]) appeared to be produced by the different bacteria on a casamino acid medium. Four out of eight species used in this study: B. linens, M. foliorum, P. vulgaris and Psychrobacter sp. showed a high flavouring potential. Among these four bacterial species, P. vulgaris had the greatest capacity to produce not only the widest varieties but also the highest quantities of volatile compounds having low olfactive thresholds such as sulphur compounds. Branched aldehydes, alcohols and esters were produced in large amounts by P. vulgaris and Psychrobacter sp. showing their capacity to breakdown the branched amino acids. This investigation shows that some common but rarely mentioned bacteria present on the surface of ripened cheeses could play a major role in cheese flavour formation and could be used to produce cheese flavours.

Serological classification and epitope specificity of Proteus vulgaris TG 251 from Proteus serogroup O65

INTRODUCTION

Proteus rods are currently subdivided into five named species, i.e. Proteus mirabilis, P. vulgaris, P. penneri, P. hauseri, and P. myxofaciens, and three unnamed Proteus genomospecies 4 to 6. Based on the serospecificity of the lipopolysaccharide (LPS; O-antigen), strains of P. mirabilis and P. vulgaris were divided into 49 O-serogroups and 11 additional O-serogroups were proposed later. About 15 further O-serogroups have been proposed for the third medically important species, P. penneri. Here the serological classification of P. vulgaris strain TG 251, which does not belong to these serogroups, is reported. Serological investigations also allowed characterization of the epitope specificity of its LPS.

MATERIALS AND METHODS

Purified LPSs from five Proteus strains were used as antigens in enzyme immunosorbent assay (EIA), SDS/PAGE, and Western blot and alkali-treated LPSs in the passive immunohemolysis (PIH) test, inhibition of PIH and EIA, and absorption of the rabbit polyclonal O-antisera with the respective LPS.

RESULTS

The serological studies of P. vulgaris TG 251 LPS indicated the identity of its O-polysaccharide with that of P. penneri O65. The antibody specificities of P. vulgaris TG 251 and P. penneri O65 O-antisera, were described.

CONCLUSIONS

P. vulgaris TG 251 was classified to the Proteus O65 serogroup. Two disaccharide-associated epitopes present in P. vulgaris TG 251 and P. penneri O65 LPSs are suggested to be responsible for cross-reactions with three heterologous Proteus strains.

In vivo evaluation of teicoplanin- and calcium sulfate-loaded PMMA bone cement in preventing implant-related osteomyelitis in rats

The objective of this study was to evaluate the efficacy of teicoplanin- and calcium sulphate-loaded polymethylmethacrylate (PMMA) bone cements in preventing experimental implant-related osteomyelitis in rats. Four groups of antibiotic-loaded rods were prepared and were implanted into the lateral condylus of the rat femur after inoculation of Staphylococcus aureus. The effectiveness of these were assessed microbiologically, radiographically, and histopathologically. Radiographic evaluation revealed a significant reduction of periostal reaction and osteolysis in rats that received calcium sulphate- and teicoplanin-loaded rods. Histopathological evaluation confirmed these results. Acute infection and bone necrosis were found to be significantly lower in rats that had received calcium sulphate- and teicoplanin-loaded rods. The addition of calcium sulfate to teicoplanin-loaded PMMA bone cement appeared satisfactory as an antibiotic-carrying system for prophylaxis of experimental implant-related osteomyelitis, but further investigations are needed to reach definitive statements for clinical applications.

[Isolation, identification, phylogenetic analysis and related properties of a pathogen in Silurus meridionalis Chen]

In October 2005, a large number of adults of Silurus meridionalis Chen died in the mud fish farming of Sichuan province. Later, three predominate strains of bacteria were isolated from the body of moribund fish. By artificial infection tests, strain TWN3 was confirmed to be the pathogen of the disease. Based on the characteristics of morphology, physiology and biochemistry tests, TWN3 was initially identified as Proteus vulgaris, and its G + C content of DNA is 39.1% . After being amplified, the sequence of its 16S rDNA was analyzed in the database of NCBI and it showed that TWN3 had the highest similarity to P. vulgaris, with 99.52% identity. By constructing the molecular phylogenetic dendrogram with Minimum Evolution method in Mega3.1, it was revealed that TWN3 was in the same branch with P. vulgaris. Based on all the results above, TWN3 is identified as P. vulgaris. However, the result of one biochemistry test, growth in KCN, deviates from the description in Bergey's Manual of Systematic Bacteriology. With reference to the Manual above, Proteus vulgaris is divided into two groups, P. vulgaris BG2 and 3. According to the specific biochemical properties, TWN3 is classified as a member of P. vulgaris BG3. Relevant tests of biological properties were also conducted, which showed that this strain has no haemolysis and is sensitive to four kinds of antibiotic such as gentamicin. Moreover, it can strongly cause diseases to mice. The research on the growth property of strain TWN3 indicated that its growth temperature ranges from 10 degrees C to 43 degrees C , optimum 37 degrees C ; growth pH ranges from 4 to 11, optimum 6. Its optimum salinity varies under different temperatures, and it grows best under 1.5 % salinity while 37 degrees C. The aim of these researches is to provide an evidence for the prevention and cure of TWN3. According to the appearance of the diseased Silurus meridionalis Chen and results of artificial infection test on crucian carps, it is considered that Silurus meridionalis Chen is infected through digestive system and it is also recommended that Bdellovibrio should be used in biological control. Although the pathogenicity of P. vulgaris is extensive, there has been no report that P. vulgaris is considered as the pathogen of cultivated Silurus meridionalis Chen so far. In addition, the identification of strain TWN3 has positive effects on the future research on the taxonomy of Proteus.

MICREDOX®—development of a ferricyanide-mediated rapid biochemical oxygen demand method using an immobilised Proteus vulgaris biocomponent

Biochemical oxygen demand (BOD) is an international regulatory environmental index for monitoring organic pollutants in wastewater and the current legislated standard test for BOD monitoring requires 5 days to complete (BOD5 test). We are developing a rapid microbial technique, MICREDOX, for measuring BOD by eliminating oxygen and, instead, quantifying an equivalent biochemical co-substrate demand, the co-substrate being a redox mediator. Elevated concentrations of Proteus vulgaris, either as free cells or immobilised in Lentikat disks, were incubated with an excess of redox mediator (potassium hexacyanoferrate(III)) and organic substrate for 1h at 37 degrees C without oxygen. The addition of substrate increased the catabolic activity of the microorganisms and the accumulation of reduced mediator, which was subsequently re-oxidised at a working electrode generating a current quantifiable by a coulometric transducer. The recorded currents were converted to their BOD5 equivalent with the only assumption being a fixed conversion of substrate and known stoichiometry. Measurements are reported both for the BOD5 calibration standard solution (150 mg l(-1) glucose, 150 mg l(-1) glutamic acid) and for filtered effluent sampled from a wastewater treatment plant. The inclusion of a highly soluble mediator in place of oxygen facilitated a high ferricyanide concentration in the incubation, which in turn permitted increased concentrations of microorganisms to be used. This substantially reduced the incubation time, from 5 days to 1h, for the biological oxidation of substrates equivalent to those observed using the standard BOD5 test. Stoichiometric conversion efficiencies for the oxidation of the standard substrate by P. vulgaris were typically 60% for free cells and 35-50% for immobilised cells.

Structure of the O-polysaccharide of Proteus serogroup O34 containing 2-acetamido-2-deoxy-α-d-galactosyl phosphate

On mild acid degradation of the lipopolysaccharide of Proteus vulgaris O34, strain CCUG 4669, the O-polysaccharide was cleaved at a glycosyl-phosphate linkage that is present in the main chain. The resultant phosphorylated oligosaccharides and an alkali-treated lipopolysaccharide were studied by sugar and methylation analyses along with 1H and 13C NMR spectroscopy, and the following structure of the branched tetrasaccharide phosphate repeating unit of the O-polysaccharide was established: [carbohydrate structure: see text]The O-polysaccharide of Proteus mirabilis strain TG 276 was found to have the same structure and, based on the structural and serological data, this strain was proposed to be classified into the same Proteus serogroup O34.

[Pyomyositis]

Pyomyositis is a bacterial infection of skeletal muscle. It is a rare condition which cannot easily be diagnosed. A fatal case of pyomyositis in a 78-year-old man is presented. The clinical signs and diagnostics of pyomyositis are discussed.

Venous sinus thrombosis after Proteus vulgaris meningitis and concomitant Clostridium abscess formation

A 19-y-old woman presented with Proteus vulgaris meningitis as a complication of chronic otitis media. Despite treatment with ceftazidime and amikacin no clinical improvement was observed. Cranial MRI revealed right-sided mastoiditis/otitis media and venous sinus thrombosis. After mastoidectomy, repeat cranial MRI demonstrated abscess formation in the venous sinuses. The abscess was drained. Clostridium spp. was isolated from the abscess culture.

[Recurrent purulent bacterial meningoencephalitis]

During the period of 25 years there were 55 patients treated in our Institute because of recurrent purulent bacterial meningoencephalitis(rpbme). This group consisted of 42 males (76%) and 13 (24%) females, the prevalent number (53%) of patients being under 21 years of age. The diagnosis of rpbme was based on the commonly accepted criteria and confirmed by the laboratory results of CSF examination. The cause of the recurrences was established considering the skull X-ray examination, CT and MRI. The evaluation of the clinical status was based on the Glasgow Coma Score (GCS). During the first hospitalisation, severe or critic clinical status was noted in 42 patients (76%) and moderate in 13 (24%). The subsequent recurrences were mostly moderate, rarely severe or mild. The number of recurrences varied from 1 to 9. During the first hospitalisation, the etiologic factor was detected in 39 patients (71%), i.e. Streptococcus pneumoniae in 28 (51%), Neisseria meningitidis in 8 (14%), Pseudomonas aeruginosa and Staphylococcus aureus in 2 and 1 patients respectively. In 37 patients (67%) rpbme developed following cranial trauma, in 18 cases (33%) with single or comminuted fractures of the anterior cranial fossa (in 4 cases accompanied by CSF nasal exsudate). In 4 it followed neurosurgical intervention, in 3 it accompanied recurrent purulent highmorities, in 1 case--after removal of the nasal polyps and subsequent CSF nasal exsudate, and in 1 patient with recurrent mastoiditis. In 6 cases (11%) the cause of the recurrences remained unelucidated. The clinical signs and symptoms, diagnostic difficulties and the causative treatment of rpbme are discussed. In the authors' opinion, surgical treatment of the communication between the CSF and the external environment prevents the recurrences and is the only successful way of treatment. Special attention is drawn to the great diagnostic value of CT and MRI. The use of other modern techniques, e.g. positron emission tomography (PET) is recommended, because it is useful not only in the functional evaluation of the cerebral tissue after the injury, but also in assessing the dynamics of pathologic changes.

R-factor in Proteus vulgaris from ulcerative disease of fish, Channa punctatus

A Proteus vulgaris isolated from external ulcers of the fresh water fish Channa punctatus showed multidrug resistance and heavy metal tolerance. The isolate from the ulcer showed resistance to chloramphenicol (Ch), nalidixic acid (Nx), streptomycin (Str) and tetracycline (Tet) with minimum inhibitory concentration (MIC) values of 750, 150, 75 and 125 microg/ml, respectively. The isolate showed growth in medium containing cadmium (Cd2+), up to a concentration of 2.5 mM indicating its heavy metal tolerance. Resistance to Ch, Str, Tet and Cd2+ of the isolate was lost after plasmid curing. Presence of plasmid DNA in the wild type and its absence in the cured P. vulgaris suggested that the resistance were plasmid mediated.

Effect of subclinical uterine infection on cervical and uterine involution, estrous activity and fertility in postpartum buffaloes

Nili-Ravi buffaloes (n=29) that calved normally between August and November and did not develop any clinical reproductive disorder after calving were studied for the incidence of sub-clinical bacterial infection of the uterus and its effects on postpartum reproductive efficiency. The incidence of subclinical uterine infection was 24% (7/29). Involution of the cervix and uterus was slower (P < 0.01) in the infected group than in the normal group (45.6 vs 31.1 days and 46.3 vs 35.8 days), respectively. The mean diameters of cervix and gravid horn on Day 12 post partum and on completion of involution did not differ between buffaloes of the two groups. However, the rate of involution of the cervix and the gravid horn was lower in buffaloes of the infected group (2.2 vs. 2.7 mm/day and 2.6 vs. 3.2 mm/day). The mean interval to first post partum ovulation was similar in buffaloes in the infected (35.5 days) and the normal group (33.8 days). The life span of corpus luteum formed after first ovulation was shorter (11 days) in buffaloes of both groups than that of a normal estrous cycle (15 to 17 days). The incidence of silent ovulation was apparently higher in buffaloes of the infected group (83 vs. 60%) but the difference was not significant. For the first four months after calving, the mean interval to first postpartum estrus was longer in buffaloes of the infected group (73.0 vs. 47.7 days; P < 0.01). Similarly, the average service period was longer in buffaloes of the infected group (91.0 vs. 64.8 days; P < 0.05). The overall pregnancy rate for the first four months after calving did not differ between buffaloes of the two groups. We conclude that subclinical bacterial infection of the postpartum uterus delays the cervical and uterine involution which can, in turn, delay the occurrence of first postpartum estrus and prolong the service period in buffaloes.

PCR-based identification of postmortem microbial contaminants--a preliminary study

Investigation of postmortem blood can reveal the presence of significant ethanol levels. However, in some instances it cannot easily be determined if the source of ethanol is from ingestion or from postmortem endogenous fermentation by contaminating microbes. Described here is a robust polymerase chain reaction (PCR)-based method for detecting the presence of common ethanol producing microbial contaminants in human blood. A set of DNA primers were designed for use in PCR to amplify and detect the genomic DNA from humans and three test microorganisms Escherichia coli, Proteus vulgaris, and Candida albicans. A rapid and reproducible protocol was developed for isolating genomic DNA from mixed human blood-microorganism samples that yields a suitable template for PCR. The organism-specific primer pairs can detect the presence of the target microorganisms in human blood at concentrations as low as 10 colony forming units/mL. The PCR products readily can be detected after agarose gel electrophoresis. This method provides an additional means of rapidly identifying microbial contaminants in postmortem blood samples.

Infectious dermatitis in a ball python (Python regius) colony

Seven wild-caught ball pythons (Python regius), including six gravid females and one male, were obtained from Africa and were housed in a government animal facility in Research Triangle Park, North Carolina. Upon arrival, the snakes were found to be infested with ticks (Aponomma latus), which were manually removed. Four weeks following arrival, vesicular skin lesions began to appear on the snakes. Despite treatment of all affected female snakes with amikacin (5 mg/kg i.m., every 3 days) and cefotaxime (25 mg/kg i.m., every 3 days), the condition progressed and five of the female snakes died 7 wk after arrival. The remaining male and one female improved after an increase in environmental temperature, with ecdysis followed by healing. Physiologic stress, ectoparasites, and shipping may have predisposed the snakes to sepsis.

Recurrent bacterial meningitis: a 6-year experience in adult patients

Ten adult patients with recurrent bacterial meningitis (RBM) of 22 episodes were diagnosed and treated at the Dicle University Hospital from January 1990 to December 1995. Apart from 22 episodes of RBM these patients had an additional 25 episodes treated at other hospitals. The RBM attacks developed after closed head trauma in four patients, asplenia and chronic otitis media in one patient, chronic otitis media and oto-mastoiditis in one patient, chronic maxillary sinusitis in one patient, chronic mastoiditis in one patients, and suppurative foci of facial bones caused by shrapnel pieces and no predisposing condition in one patient. In 10 RBM episodes, Streptococcus pneumoniae was isolated from cerebrospinal fluid (CSF) and/or blood culture, and in one episode Proteus vulgaris was isolated from CSF and otitis media suppuration. In the four episodes both cultures were negative, but direct microscopy showed Gram-positive diplococci on Gram-staining. Three of the patients died from meningitis-related complications.

Differentiation of Proteus mirabilis and Proteus vulgaris strains by means of proticine typing: a longitudinal epidemiological study

In the years 1979, 1980, 1982-83, 1986-87 and 1992-93, 673 strains of P. mirabilis and 25 strains of P. vulgaris were isolated from the urinary tracts of patients at a Teaching Hospital in Brno. In 1982-83 and 1992-93, strains of P. mirabilis and P. vulgaris were isolated from the urine and faeces of two groups of Brno population and used as controls. Using the P/S typing method, 94.7% of hospital isolates and 85.5% of control strains could be differentiated by their types. The strains that could not be typed (8.2%) were classified as PO/SO or N types; in the remaining strains, 182 various P/S types could be distinguished. The strains that could not be typed occurred more frequently in control groups (48 out of 337) than in hospital isolates (37 out of 698). Over the whole period, P5/S6, S7, S9 and P1/S2, S11 were the prevailing P/S types of hospital isolates and were placed, together with related types, in groups P5 and P1, respectively. In 1982-83, a significant shift (p < 0.01) from the initially prevailing P5/S6, S7, S9 type to the P1/S2, S11 type of P. mirabilis was recorded. Approximately one third of the hospital isolates in all the periods examined was found to be sporadic, with the exception of 1992-93 when the sporadic strains doubled in frequency (p < 0.01). In control strains, the frequency of sporadic types was twice that of the hospital isolates (p < 0.01) in 1982-83 and, 1992-93, it was equal to the frequency of hospital isolates. This implied a fall in the presence of hospital-acquired strains in the last period of study.

[Acute clostridium difficile gastroenteritis infection in children: report of three cases]

The causes and clinical manifestations of Clostridium difficile infection in children are described in this report. The studies were performed on three children aged up to 3 years. Risk factors as well as possible diagnostic and therapeutic procedures are discussed.

An in-vitro study of smear layer removal and microbial leakage along root-canal fillings

The objective of this study was to determine the effect of removal of the smear layer on canal obturation as measured by penetration of bacteria from a coronal direction. Fifty-four extracted human teeth were decoronated and instrumented in a uniform manner. Following instrumentation the root canals of 20 teeth were rinsed with 17% EDTA and 5.25% NaOCl to remove the smear layer before obturation. A second group of 20 teeth were flushed with NaOCl alone. The teeth of both groups were obturated with Thermafil plastic carriers and Roth's sealer. The root canals of another 10 teeth, five rinsed with EDTA and five without, were obturated with Thermafil without sealer. Two teeth serving as positive controls were instrumented but not obturated, while another set of two were sealed coronally and apically to serve as negative controls. The root surface of each tooth was sealed with nail varnish. A small chamber was thoroughly sealed around the coronal aspect of each tooth so that bacteria placed therein could move only through the obturated canal space. Each tooth was placed in a test tube containing sterile trypticase soy broth (TSB). An inoculum of Proteus vulgaris in TSB was placed in each coronal chamber at five day intervals and daily observations were made for bacterial growth in the apical reservoir for 21 days. Both positive control teeth showed bacterial penetration after 24 h. Neither of the two negative control teeth demonstrated penetration for the duration of the study. The frequency of bacterial penetration through teeth obturated with intact smear layer (70%) was-significantly greater than that of teeth from which the smear layer had been removed (30%) P < 0.05. All but one tooth obturated without sealer exhibited bacterial penetration, irrespective of the presence or absence of smear layer. Removal of the smear layer enhanced sealability as evidenced by increased resistance to bacterial penetration.

[The value of bacteriologic examination in cataract surgery]

The purpose of our study was to compare the incidence of intrabulbar infections following cataract extraction and its correlation with the results of preoperative bacterial cultures. We examined 2344 patients who were operated on from 1st January 1993 to 31st December 1994 in our hospital. Patients were divided into 3 groups. In the first group surgery, was performed only in cases where preoperative cultures were negative, in the second group conjunctival cultures were prepared just before surgery. In the third group no preoperative cultures were prepared. Additionally in the second and the third group one drop of 5% Betadine solution was administered to the conjunctival sack just before surgery. We conclude that negative preoperative conjunctival cultures did not prevent from postoperative infections of the eye. After resigning of preoperative bacterial cultures the incidence of intrabulbar infections following cataract surgery did not increase in our study.

Xanthogranulomatous pyelonephritis--an unusual renal disease in childhood

We report on a 6-year-old boy with Xanthogranulomatous pyelonephritis. This unusual type of renal inflammation has a typical clinical picture that is important to bear in mind. The affected child is often seriously ill with a palpable flank mass leading to initial suspicion of malignancy. Modern imaging procedures help in obtaining a pre-operative diagnosis.

Characterization of an alkaline lipase from Proteus vulgaris K80 and the DNA sequence of the encoding gene

A facultatively anaerobic bacterium producing an extracellular alkaline lipase was isolated from the soil collected near a sewage disposal plant in Korea and identified to be a strain of Proteus vulgaris. The molecular mass of the purified lipase K80 was estimated to be 31 kDa by SDS-PAGE. It was found to be an alkaline enzyme having maximum hydrolytic activity at pH 10, while fairly stable in a wide pH range from 5 to 11. The gene for lipase K80 was cloned in Escherichia coli. Sequence analysis showed an open reading frame of 861 bp coding for a polypeptide of 287 amino acid residues. The deduced amino acid sequence of the lipase gene had 46.3% identity to the lipase from Pseudomonas fragi.

A new phage typing scheme for Proteus mirabilis and Proteus vulgaris strains. 1. Morphological analysis

A new bacteriophage typing set, composed of 22 phages, was established as a tool for differentiation of Proteus strains. All the phages were tailed and included 4 morphological types (A1, A2, B1 and C1). They were classified into the families Myoviridae, Siphoviridae and Podoviridae. From the set, 19 phages had double-stranded DNA and 3 were single-stranded DNA phages.

Predictive accuracy of disk diffusion test for Proteus vulgaris and Providencia species against five newer orally administered cephalosporins, cefdinir, cefetamet, cefprozil, cefuroxime, and loracarbef

Three members of the tribe Proteeae (Proteus vulgaris, Providencia rettgeri, and Providencia stuartii) were tested against five newer orally administered cephalosporins (cefdinir, cefprozil, cefuroxime, cefetamet, and loracarbef) by the disk diffusion and reference broth microdilution methods. One hundred strains of these organisms were tested to confirm the excessive interpretive error rates that previously had been noted for the disk diffusion test. The results indicate that the suggested disk diffusion breakpoints for cefetamet and cefuroxime were without serious interpretive errors. In contrast, loracarbef, cefdinir, and cefprozil results exceeded acceptable interpretive error rates, with very major (false-susceptible) errors of 4, 5, and 9% respectively. Loracarbef currently has a warning in the National Committee for Clinical Laboratory Standards table footnotes addressing this problem. We recommend including cefdinir and cefprozil in the list of compounds requiring this warning. In addition, MICs of cefazolin, cefaclor, and cephalothin were determined to establish whether a class MIC concept to predict susceptibility for these agents was possible. When the indole-positive Proteus strains are tested, cefazolin MICs can be used to predict MICs of all tested orally administered cephems (8 to 13% total errors, with only a 0 to 1% very major error.

Human saliva penetration of coronally unsealed obturated root canals

Studies have shown significant coronal dye and bacterial leakage following exposure of sealed root canals to artificial and natural saliva. The purpose of this study was to determine the time needed for bacteria in natural saliva to contaminate the entire length of root canals obturated by lateral and vertical condensation techniques. Forty root canals were cleaned and shaped using a step-back technique. Thirty root canals were obturated with gutta-percha and root canal sealer using either lateral or vertical condensation techniques. Forty root canals were obturated without a root canal sealer and served as positive controls. After obturation, the coronal 3 mm of five root canals were sealed with sticky wax and served as negative controls. The coronal portions of the filling materials were placed in contact with human saliva and the number of days required for bacteria in saliva to penetrate the entire root canals were determined. No bacterial leakage occurred in the negative control group. Complete bacterial leakage occurred within 2 days in the positive control group. All root canals were recontaminated in less than 30 days. No statistical significant difference was found between the two methods of obturation.

The incidence and beta-lactam resistance of Proteus vulgaris in hospital infections: the last decade

During the period of 1980-1990, 581 Proteus vulgaris strains were obtained in a general hospital. They were considered as the significant isolate in 0.6% of soft tissue infections, 0.6% of urinary tract infections and in 0.2% of bacteremic episodes. Sixty-three percent of the 393 tested strains showed resistance to ampicillin, cefazolin and cefamandole or cefuroxime. About 7% were susceptible to all beta-lactam drugs, and showed a very low beta-lactamase activity and 5% of the strains showed a phenotype of resistance including ampicillin, carbenicillin-ticarcillin, cefazolin and cefamandole or cefuroxime, and presented increased chromosomal beta-lactamase activity. Cefotaxime-resistance was detected in 2% of the isolates which appeared in the period 1987-1990.

[The enterotoxigenic capacity of hemolysin-producing strains of Proteus isolated in acute intestinal infections in children]

The capacity of P. mirabilis and P. vulgaris strains isolated in acute enteric infections in children for producing enterohemolysin, a new type of hemolysin, has been shown. The relationship between the capacity of Proteus cultures for producing enterohemolysin and their capacity for inducing toxic secretory reaction on a ligated loop on the small intestine of rabbits in the absence of known thermostable and thermolabile antitoxin in bacteria.

[Vena cava superior syndrome in total parenteral nutrition. Vena cava superior thrombosis caused by a central venous catheter]

Two patients developed superior vena cava syndrome following total parenteral nutrition through a central venous catheter. Infection may have contributed to the development of the superior vena cava thromboses. In one patient a "sleeve thrombus" probably caused multiple pulmonary embolisms after the catheter was withdrawn. The other patient had a mural thrombosis with complete occlusion of the superior vena cava. The author emphasizes the importance of early diagnosis and correct treatment in order to reduce the high mortality rate due to this serious complication to central venous catheters.

New screening test to determine the acceptability of 0.45-micron membrane filters for analysis of water

During routine membrane filter (MF) quality control testing, irregularities such as partial or complete inhibition of microbial growth at grid lines, abnormal spreading of colonies, growth in or along the grid lines, nonwetting areas, poor colony sheen and metallic sheen on the MF surface with mEndo agar, brittleness, decreased recovery, and severe wrinkling were observed with several lots of filters. To study these effects and to develop a more sensitive screening test for MF quality, we compared five different MFs with various types and degrees of defects by using five stock coliform cultures and five different media. Results showed that the Enterobacter aerogenes-tryptic soy agar test system detected more MF defects than any other combination did and was superior to the Escherichia coli-mFC agar American Society for Testing and Materials method for grid line inhibition. Filtered natural samples grown on the same media showed the same effects as were observed with the pure cultures. Poor colony sheen and sheen on the MF surface were best detected with Enterobacter aerogenes on mEndo agar. The use of tryptic soy agar and mEndo agar with this organism permitted the maximum detection of MF irregularities. Of the 142 MF lots tested by this method, 30% were acceptable, 10% were marginally acceptable, and 61% were unacceptable. This method provides a valuable screening test for determining the acceptability of 0.45-microm-pore-size MFs used for coliform and heterotroph analysis and may also be useful in conjunction with other methods.

[The detection of a choleriform thermolabile enterotoxin in clinical strains of Proteus isolated in different infections]

The capacity of Proteus strains, isolated from patients with purulent inflammatory, urological and enteric infections, for the production of choleriform thermolabile enterotoxin was studied by means of the enzyme immunoassay (EIA) with the use of antitoxic serum to Escherichia coli enterotoxin. Out of 125 strains, 27 (21.6%) showed the capacity for producing choleriform thermolabile enterotoxin in EIA experiments. The results thus obtained indicate that EIA techniques can be used, in principle, for detecting the capacity of Proteus for the production of choleriform thermolabile enterotoxin.

Detection by light microscopy of Candida in thin sections of bladder stone

We detected fungi morphologically resembling Candida albicans in an infected bladder stone by light microscopy of thin sections. The fungi were found in the layers precipitated with oxalate crystals and were invading the interstices surrounded with apatite or struvite crystals as in tissue infection. This presumably represents a superimposed infection due to changes in flora following treatment with antibiotics.

[Clinico-experimental study of a dried selective medium for isolating fungi in the genus Candida]

The trial of a newly developed dried selective medium for the isolation of fungi of the genus Candida, involving the inoculation of 103 museum yeast strains and 542 specimens of pathological material, has been carried out. The data obtained in this trial indicate that the proposed medium has advantages over wort agar and Sabouraud medium with antibiotics in the germination index, in the ability to ensure fungal growth after the inoculation of pathological material, and in selective properties. The medium ensures the intactness of the morpho-cultural, biochemical and serological properties of the fungi. The results of the trial recommend the newly developed preparation for laboratory practice for the isolation of yeast-like fungi from clinical material in the diagnosis of candidiasis, intestinal microflora disturbances, as well as for isolation of the fungi from various environmental objects.

[Sensitivity to beta-lactam and aminoglycoside antibiotics of clinical Proteus strains as dependent upon on their species classification and the source of their isolation]

Sensitivity of 130 Proteus clinical strains was studied. Among beta-lactam antibiotics cefotaxime showed marked advantages with respect to various Proteus species. All the isolates of Proteus mirabilis were sensitive to cefuroxime. Cefamezin and cephapirin were inferior by their activity to cefotaxime and cefuroxime. They were characterized by close antibacterial activity and almost complete cross resistance. Ampicillin and carbenicillin proved to be the least efficient among the tested beta-lactam antibiotics. Isolates of Proteus vulgaris and Proteus penneri were more resistant to the penicillins and cephalosporins than the cultures of Proteus mirabilis. Sensitivity of separate Proteus species to gentamicin, tobramycin, sisomicin and amikacin was close. No cross resistance to the aminoglycosides was detected. Studies on the effect of different doses of the antibiotics revealed pronounced heterogeneity of Proteus by the feature of sensitivity to the tested antibiotics. The level of the heterogeneity was not the same for separate antibiotics. Cultures of Proteus mirabilis resistant to ampicillin, carbenicillin, cefamezin and cephapirin were more frequent in patients with urogenital infections as compared to patients with intestinal infections and suppurative-inflammatory processes of other localization.

Speciation, serotyping, antimicrobial sensitivity and plasmid content of Proteeae from the environment of calf-rearing units in South West England

A survey was undertaken of the occurrence, serotype, antimicrobial sensitivity and plasmid content of members of the tribe Proteeae in the environment of two calf-rearing units in the county of Avon in South West England. Examples of the following species were found: Proteus mirabilis, Prot. vulgaris, Prot. vulgaris Biogroup 2, Morganella morganii, Providencia stuartii, Prov. alcalifaciens and Prov. rettgeri. A wide range of serotypes was found, many having been previously reported from nosocomial isolates. A total of 15% of isolates carried plasmids; six pairs of isolates were identified which had identical serotypes but different patterns of plasmid carriage. The antimicrobial sensitivity of the isolates was generally similar to isolates of Proteeae from humans. Although no truly aminoglycoside-resistant isolates were found, some isolates of Prov. stuartii and Prov. rettgeri had MIC's higher than the other isolates to gentamicin and netilmicin, suggesting the presence of low levels of the enzyme AAC 2'. The study demonstrates that there is a considerable diversity of species and types of Proteeae associated with calves and their environment. It seems likely that a potential cause of colonization of the human gut by Proteeae is the consumption of meat.

Significance of non-pathogenic cross reactive bowel flora in patients with ankylosing spondylitis

We have previously shown that antisera raised in rabbits to certain enteric cross reactive strains of bacteria are capable of specifically lysing the peripheral blood lymphocytes of HLA-B27 positive patients with ankylosing spondylitis (B27+ AS+). We now report that bacteria with cross reactive antigenic determinants are found in the bowel flora of all of 52 B27+ AS+ patients but in only one of 50 HLA-B27 positive normal controls (B27+ AS-). These organisms are functionally similar to the cross reactive enteric bacteria originally reported. They are not confined to a particular genus or species and their cross reactive serological nature appears to be a property shared by all enteric organisms isolated from B27+ AS+ patients. Organisms with these properties have been shown to persist in the bowel flora of 14 B27+ AS+ patients followed up for more than one year.

A survived case of diabetic nonclostridial gas gangrene and the review of the literatures on microbiological findings

Nonclostridial gas gangrene in diabetics results in poor prognosis. In this paper, a survived case of diabetic nonclostridial gas gangrene caused by Proteus vulgaris and Streptococcus faecalis is described and microbiological findings of 31 cases of the literatures including our own case were reviewed. Twenty of 31 cases died (64.5%). The microbiological findings in 30 cases revealed an average of 1.8 organism per case. Predominant aerobes were E. Coli (56.7%), Streptococcus faecalis (16.7%), aerobic Streptococcus and Proteus (both 13.3%) in that order. Anaerobes were found in 12 of 20 cases and isolated anaerobes were Bacteroides (8 cases) and Peptococcus (4 cases). The role of specific bacteria in causing severe form of nonclostridial gas gangrene in diabetics was suggested.

[Comparative evaluation of different methods for typing bacteria in the genus Proteus]

The work presents the comparative evaluation of different methods used for differentiating bacteria of the genus Proteus. A scheme of the combined typing of Proteus is presented. This scheme includes the determination of enzymatic and serological variants with the subsequent additional bacteriocinogenic and phage typing. Among the Proteus strains in our collection (600 strains), 123 sero-enzymatic variants, 71 enzymo-lysogenic variants, 64 enzymo-bacteriocinogenic variants, 162 sero-lysogenic variants, 164 sero-bacteriocinogenic variants and 52 bacteriocinogeno-lysogenic variants have been detected.

Rare occurrence of Proteus vulgaris in faeces: a reason for its rare association with urinary tract infections

The faecal carriage rates of different species of Proteeae were assessed in studies with 220 faecal isolates from 219 individuals of whom approximately one-third were well and the remainder had gastro-enteritis. As a result of the development of new media that allowed replacement of the phenylalanine deaminase test with the tryptophan deaminase test and made it possible to combine tests for indole and urease production and for hydrogen sulphide and ornithine decarboxylase formation in two single-tube tests, all strains were speciated with speed, economy and accuracy. Most (96%) isolates were either Proteus mirabilis (62%) or Morganella morgani (34%). The significance of these findings in relation to urinary tract infection is discussed. P. vulgaris was found in only one (0.45%) faecal specimen and this rarity of carriage in faeces is believed to be the main reason for its rare association with urinary tract infections. The frequent association of M. morgani, in the absence of other enteropathogenic bacteria, with severe gastroenteritis was noted with interest.

[Changes in the migration and adhesive activity of polymorphonuclear leukocytes as 1 of the characteristics of Gram-negative bacteria isolated from patients with suppurative lung destruction]

The influence of Gram-negative bacteria on the migratory and adhesive activity of polymorphonuclear leukocytes (PMNL) in the peripheral blood of clinically normal donors has been studied by the specially developed method with the use of Boyden chambers. Pseudomonas and enterobacteria have been found to produce complex and various effects on the above-mentioned properties of PMNL. When incubated in fresh serum, Gram-negative bacteria are capable of enhancing the migratory activity of PMNL, this property being least pronounced in P. aeruginosa. The incubation of live bacteria from the authors' collection in the patients' sera or in sera obtained from normal donors and inactivated by heating induces no hemotaxis of PMNL, and P. aeruginosa strains even suppress it under such conditions. The isolated Gram-negative bacteria under study increase the number of highly adhesive PMNL in the population used in this investigation, but P. aeruginosa cultures do not produce such effect.

Bacteriology of sore throats in a Sudanese population

One hundred and eighty-six throat swabs were collected from patients with sore throats and 164 throat swabs were collected from healthy controls. All swabs were investigated bacteriologically, and sensitivity tests were performed on all pathogenic isolates. Group A Streptococcus pyogenes was the predominant pathogenic organism (24.7%) and Proteus vulgaris the least predominant organism (0.5%) isolated from patients with sore throats. Streptococcus pyogenes infection was found to be most common among school children between the ages of 9 and 12 (61.5%). The pathogenic organisms were found to be sensitive to erythromycin (92.6%).

[Characteristics of bacteria in the genus Proteus isolated from patients with sporadic and group intestinal diseases]

The biochemical and biological properties of 148 Proteus strains isolated from patients both in sporadic intestinal infections and in a case of group infection in children's hospital was studied. The study revealed that the etiological factor of the group infection was P. mirabilis belonging to rare serovar 48:2. Proteus organisms isolated in sporadic infections belonged to a great number of serovars. No relationship between the isolated serovar and the nosological form of the intestinal disease was established. Among the Proteus strains under study, 82 strains showed atypical biochemical properties in 1 test or more. No correlation between the clinical diagnosis and the occurrence of atypical strains was established.

The association of particular types of Proteus with chronic suppurative otitis media

During a period of 12 months, 57 strains of Proteus were isolated from the ears of 38 unrelated patients with chronic suppurative otitis media. Each strain was identified, typed for bacteriocin production and sensitivity, and tested for Dienes compatibility. The majority of the strains (79%) were P. mirabilis; all but one of the remainder were P.vulgaris. Although 19 different bacteriocin production/sensitivity types were found, two rare types, P. mirabilis P7/S5,12 and P. vulgaris P0/S9, were associated with 47% of these infections. This was confirmed by Dienes typing. Patients with bilateral ear disease carried a different strain in each ear. There was no evidence that persistence of infection had arisen because of the development of antibiotic resistance. Although there was some evidence that persistence may have been the result of reinfection, the isolation of these rare types of Proteus from so many patients with chronic suppurative otitis media may indicate that they play an important role in the pathogenesis of the disease. Most of the Proteus isolates were of "non-faecal" types and it is believed that infection had arisen by a route other than the faecal-aural one.

[Protective properties of Proteus ribosomal vaccine]

The results of the study of the protective properties of Proteus ribosomal vaccine prepared from P. vulgaris museum strain F-30 are presented. The vaccine showed protective effect even in a dose of 0.0001 microgram of protein per mouse; when used in immunization doses of 1 and 10 micrograms of protein per mouse, the vaccine completely protected the animals, ensuring their survival. Experiments aimed at the determination of the maximum protective effect of the vaccine were carried out. The ribosomal vaccine injected in a dose of 1 microgram of protein per mouse protected 50% of mice challenged with 10 LD50; in a dose of 10 micrograms of protein per mouse the vaccine protected 100% of the animals challenged with 3.7 and 10 LD50. Proteus ribosomal vaccine prepared from P. vulgaris museum strain was shown to render protective effect with respect to P. vulgaris and P. mirabilis clinical strains.

[Combined media for the simplified and rapid identification of bacteria of the Proteus-Providencia group]

Three combined media ensuring the determination of 8 characteristics typical of bacteria belonging to the group Proteus-Providencia (tryptophane deamination, urease activity, production of hydrogen sulfite and indol, fermentation of mannitol, maltose, adonitol and inositol) are presented.