[A novel Salmonella Typhimurium plasmid, pAnkS: an example for plasmid evolution in antibiotic resistance]

In this study, a plasmid, carrying ampicillin resistance (ampR) gene, isolated from a clinical isolate of Salmonella enterica serotype Typhimurium presenting ACSSuT (ampicilin, chloramphenicol, streptomycin, sulphonamide, tetracycline) resistance phenotype, was defined. The length of complete sequence of this plasmid was 8271 base pairs (bp), and it was named as pAnkS owing to its isolation place (plasmid-Ankara- Salmonella). The plasmid was analyzed for potential reading frames and structural features indicative of transposons and transposon relics. The Xmnl enzyme restriction fragments of pAnkS were cloned into E. coli plasmid vectors (pBSK), sequenced and analyzed with the BLAST programs. Plasmid pAnkS has contained a previously defined enterohemorrhagic E. coli (EHEC) plasmid p4821 as a core region and also contained a complete Tn3-like transposon of 4950 bp consisting of the left terminal repeat, Tn3-related tnpR and tnpA genes for transposition functions, ampicillin resistance gene bla(TEM), and the right terminal repeats, pAnkS showed strong homology with another Salmonella plasmid, pNTP16, for sequences that belong to p4821 and partial Tn3 segments. It was found that pNTP16 also carries kanamycin resistance gene (kanR) in addition to ampR gene. Plasmid pAnkS is one of the few completely sequenced plasmids from Salmonella Typhimurium and is in the middle of the pathway of evolution of plasmid from p4821 to pNTP16. The identification of pAnkS might help better understanding of plasmid evolution.

Antimicrobial resistance of Salmonella enterica group C strains isolated from humans in Turkey, 2000–2002

Fifty-three Salmonella enterica group C isolates obtained from various human samples (47 stool, 4 blood and 2 urine) in ten provinces of Turkey between 1 July 2000 and 30 June 2002 were serotyped and resistance to antimicrobials was investigated by agar dilution tests. The isolates were identified as S. Choleraesuis (11), S. Hadar (7), S. Irumu (4), S. Virchow (3), S. Tallahassee (3), S. Paratyphi C (2), S. Braenderup (2), S. Othmarschen (2), S. Menston (2), S. Concord (2), S. Infantis (2), S. Kottbus (2), S. Edinburg (1), S. Oranienburg (1), S. Muenchen (1) and S. Malmoe (1). Antimicrobial resistance rates of S. enterica groups C1 and C2 were high for ampicillin (26% and 60%, respectively), amoxicillin/clavulanic acid (11% and 40%), chloramphenicol (16% and 27%) and tetracycline (3% and 40%). The percentages of strains sensitive to all antimicrobials were 58% and 33%, respectively. Multiresistance was not observed in group C1 isolates, but the rate of multiresistant isolates was 13% in group C2. The rate of decreased ciprofloxacin susceptibility (CipL) was 61% in serogroup C1 and 20% in serogroup C2. These results indicated that S. enterica group C infections in humans were not infrequent in Turkey and that multiple antimicrobial resistance was common within these strains.

Antimicrobial resistance patterns and serotype distribution among Salmonella enterica strains in Turkey, 2000?2002

Since Turkey currently lacks a national reference center for Salmonella infections, the present study was conducted to document the distribution of serotypes and antimicrobial resistance patterns among Salmonella enterica isolates recovered from clinical samples in ten Turkish provinces over a 2-year period. Among the 620 Salmonella enterica isolates recovered between 1 July 2000 and 30 June 2002, strains belonging to the serotypes Enteritidis (47.7%), Typhimurium (34.7%), Paratyphi B (6.0%), Typhi (2.9%), Paratyphi A (0.2%) and serogroup C (8.5%) were found. Resistance to multiple antimicrobial agents was particularly high among Salmonella Typhimurium isolates (76.7%), and resistance or decreased susceptibility to ciprofloxacin (MIC> or =0.125 mg/l) was demonstrated in Salmonella Paratyphi B, Salmonella Typhimurium and Salmonella Enteritidis strains. All of the Salmonella Typhi isolates were susceptible to ciprofloxacin. The results indicate that decreased susceptibility to ciprofloxacin is an emerging problem in Salmonella enterica in Turkey, particularly in multiresistant strains.

Predictive value of nalidixic acid resistance for detecting salmonellae with decreased ciprofloxacin susceptibility

Seventy-three Salmonella isolates classified as ciprofloxacin susceptible when using the criteria of the National Committee for Clinical Laboratory Standards were studied for nalidixic acid (NA) resistance. The aim of the study was to determine the predictive value of nalidixic acid resistance in screening for decreased ciprofloxacin susceptibility. We observed that isolates with decreased ciprofloxacin susceptibility were all resistant to nalidixic acid. Identification of nalidixic acid resistance by the disk diffusion method provided 100% sensitivity and a specificity of 98.4% in strains with minimum inhibitory concentrations (MICs) >0.008 mg/l.

Pulmonary involvement in childhood-onset systemic lupus erythematosus: a report of five cases

OBJECTIVE

Systemic lupus erythematosus (SLE) is a chronic systemic disease, which can involve multiple organs such as kidney, skin and brain. Lung is another organ that can be affected. A number of pulmonary complications including pleuritis, pneumonitis, infectious pneumonia, pulmonary haemorrhage, pulmonary hypertension and pneumothorax have been reported in patients with SLE. Pulmonary involvement is relatively frequent in adult patients; it has infrequently been reported in children with SLE. However, pulmonary manifestations may be an initial and/or life-threatening complication of SLE in children. In this paper we aim to emphasize the pulmonary involvement in childhood-onset SLE via description of our patients.

METHODS

The patients, who were diagnosed with SLE at the Children's Hospital of Ankara University Medical School between 1993 and 2002, were retrospectively evaluated for evidence of pulmonary involvement. All patients fulfilled at least four of the classification criteria of the American Rheumatism Association. Using a standardized form, we obtained data regarding the age, sex and presenting complaints of the patients, previous therapies given, clinical and laboratory features, treatment and outcome. Informed consent was obtained from all patients.

RESULTS

During the 10-yr study period, 16 patients were diagnosed with childhood-onset SLE. Five of them (31%) had pulmonary involvement including acute lupus pneumonitis, invasive pulmonary aspergillosis, cytomegalovirus pneumonia and pulmonary haemorrhage (in two patients). These 5 patients with lupus lung disease are presented in more detail.

Drug resistance of Salmonella strains isolated from community infections in Ankara, Turkey, 1993-99

160 Salmonella strains were isolated from children at the paediatrics department of Ankara University. 48.1% of the isolates were Salmonella enteritidis, 41.9% Salmonella typhimurium and 10% other serotypes. For the analysis of data, the study period was divided into 2 periods: 1993-95 and 1996-99. A decline in the isolation rate of S. typhimurium (from 63.1% to 30.1%) and rapid rise in S. enteritidis (from 31.6% to 57.3) was observed during the review period. However, for S. typhimurium isolates, the 5-drug (ampicillin, chloramphenicol, streptomycin, tetracycline and sulfonamides) pattern of resistance was increased from 13.5% to 38.7% in the second period. Since S. enteritidis and 5-drug-resistant S. typhimurium have also increased in other countries, their pandemic spread in humans indicates the continuing importation and exportation of these pathogens.

Drug resistance of Shigella strains isolated in Ankara, Turkey, 1993-1996

289 Shigella strains were isolated from children at the paediatrics department of Ankara University. 75% of the isolates were S. sonnei and 24.8% were S. flexneri. Each strain was tested for resistance to 9 antimicrobial agents. 79% of the isolates were resistant to streptomycin (S), 56% to tetracycline (T), 55.7% to trimethoprim-sulfamethoxazole (SXT), 27.7% to ampicillin (Am) and 19.7% to chloramphenicol (C). None of the isolates was resistant to ciprofloxacin, nalidixic acid, cephalothin, ampicillin-sulbactam and ceftriaxone. 56% of the isolates were resistant to 3 or more antimicrobial agents. The most frequent pattern of resistance of S. sonnei and S. flexneri strains was SXT, T, S (39.6%) and Am, SXT, T, S, C (48.6%), respectively (p < 0.0001). These results demonstrate that trimethoprim-sulfamethoxazole should not be used in the treatment of shigellosis.

[In vitro activity of ofloxacin and ciprofloxacin against Mycobacterium tuberculosis strains]

The activity of Ofloxacin and Ciprofloxacin against 50 strains of M. tuberculosis were investigated in-vitro on Löwenstein-Jensen medium. Minimal Inhibitory Concentration (MIC90) of Ofloxacin and Ciprofloxacin were found 1 mg/L and 4 mg/L, respectively. There were no difference in susceptibility to Ofloxacin and Ciprofloxacin between strains which were susceptible or resistant to Standard Anti-tubercular drugs.