Moraxella catarrhalis in chronic and relapsing respiratory tract infections in children]

Examination of 700 children with chronic and relapsing respiratory tract infections showed that during the period from 1996 to 2003 Moraxella catarrhalis strains were isolated from the sputum of 5.5-9.7% of the patients. The frequency of the emergence was the third after Haemophilus influenzae and Streptococcus pneumoniae. In healthy children M. catarrhalis was isolated in 2.7% of the cases. The most frequent detection of M. catarrhalis was stated in children under 1 year (4.5%). The antibiotic susceptibility tests revealed that the majority of the M. catarrhalis isolates had beta-lactamase activity, were resistant to benzylpenicillin, ampicillin and lincomycin and highly susceptible to amoxycillin/clavulanate, macrolides, certain cephalosporins and levofloxacin. The isolates were most frequent in the patients of the rather severe contingent (congenital lung disease, alveolitis, chronic pneumonia, bronchial asthma). In such patients the bronchoobstructive syndrome was more frequent (46.6%). High frequency of the affection of the upper respiratory tracts in the examined children was stated (62.1%).     

Resistance of urinary tract infection pathogens and choice of antibacterial therapy in pediatric urologic practice]

The data on antibiotic resistance of the main uropathogens isolated from patients with urinary tract infection in an urologic department (319 isolates) and outpatient and diagnostic units (360 isolates) are presented. It was shown that by the antibiotic resistance the Escherichia coli isolates from the urologic department patients and outpatients did not practically differ: 44.1 and 47.8% of the isolates were resistant to ampicillin, 26.7 and 23.4% were resistant to amoxycillin/clavulanate, 28.9 and 24.9% were resistant to co-trimoxazole and 26.5% was resistance to cefuroxime (outpatients). The basic differences referred to Pseudomonas aeruginosa: resistance to ceftazidime in 38.5% of the isolates and resistance to gentamicin in 36.2% of the isolates. The activity against P. aeruginosa could be arranged as follows in the decreasing order: amikacin = meropenem > imipenem > cefepime = cefoperazone/sulbactam > gentamicin = ceftazidime. Resistance of P. aeruginosa to fluoroquinolones (ciprofloxacin and levofloxacin) remained low (7.4 and 8.0% respectively). No ampicillin resistance was revealed in the isolates of Enterococcus faecalis.     

Evaluation of antimicrobial regimens in a guinea-pig model of meningitis caused by Pseudomonas aeruginosa

To compare the efficacy of meropenem, ceftazidime, tobramycin and ceftazidime+tobramycin in a guinea-pig model of P. aeruginosa meningitis. After anesthesia, the atlanto-occipital membrane was punctured with a butterfly needle and 100 microl of a solution containing 10(6)CFU/ml of P. aeruginosa were injected directly into the cisterna magna. Four h later, therapy was initiated with saline or antibiotics given im for 48 h in doses that obtained CSF levels as in human meningitis: ceftazidime 200 mg/kg/8h, meropenem 200 mg/kg/8h, tobramycin 30 mg/kg/24h. Tobramycin was also given intracisternally. Animals were sacrificed at different time points. CSF and blood samples were collected and a meningeal swab was performed. Four hours after inoculation, bacterial concentration in CSF was 4 to 5log10CFU and mean WBC was 16,000/-l. All control animals died in 24h with a 12% increase in cerebral edema. All blood-cultures were negative. Ceftazidime, ceftazidime+tobramycin and meropenem reduced the CSF bacterial concentration at 8h by 2.5log10. At 48 h all CSF cultures were sterile but meningeal swab cultures remained positive in 30%. Our results suggest that meropenem may be at least as effective as ceftazidime and that the addition of tobramycin to ceftazidime may improve its efficacy.     

The structure and antibiotic sensitivity of the causative agents of community-acquired infectious diseases of bacterial origin in children]

Four hundred and forty pediatric patients at the age of 7 days to 15 years with various infections admitted to the Hospital within a month were examined. The biological material was inoculated to blood agar on the first days of the patient admittance to the Hospital and after the growth the organisms were isolated and identified. Antibiotic susceptibility of the isolates was assayed with the disk diffusion method. 479 strains in all were tested. The most frequent cases requiring hospitalization and antibiotic therapy were those of respiratory tract infections (54.09 per cent), urinary tract infections (26.36 per cent), cutaneous and subcutaneous fat diseases, gastrointestinal diseases and others (about 25 per cent of the cases in all). The main pathogens were Streptococcus viridans, S.aureus and S.epidermidis, as well as Enterobacteriaceae (chiefly E.coli) whose frequencies were practically equal (in 25-35 per cent of the cases). The Pneumococcus isolates amounted to 6.3 per cent. Nonfermenting bacteria (Pseudomonas aeruginosa and Acinetobacter) and some representatives of Enterobacteriaceae (Citrobacter, Serratia, Morganella) were isolated from 7 per cent of the patients. The frequency of Klebsiella and Enterobacter was about 11 per cent. The main pathogens were tested for their susceptibility to amoxycillin/clavulanic acid, ampicillin, oxacillin and gentamicin. The least active antibiotic was ampicillin. 88.8 per cent of the E.coli isolates and 100 per cent of the Klebsiella, P.mirabilis, Morganella, Citrobacter, Enterobacter and Serratia isolates were resistant to it. 53.2 per cent of the Streptococcus isolates including 64.5 per cent of the Pneumococcus isolates were as well resistant to ampicillin. 59.5 per cent of the Streptococcus isolates (mainly S.viridans and Enterococcus) was susceptible to oxacillin, 22.2 per cent of them being moderately susceptible. 62.5 per cent of the Pneumococcus isolates and 78.1 per cent of the Staphylococcus isolates were also susceptible to oxacillin. The highest susceptibility of the isolates was that to amoxycillin/clavulanic acid, i.e. 90.1 per cent of the strains, 79.9 per cent of them being highly susceptible. All the isolates of Citrobacter, Serratia and Morganella and some isolates of P.aeruginosa, Acinetobacter, Enterobacter, Klebsiella and E.coli were resistant to amoxycillin/clavulanic acid. As for the latter 5 organisms their susceptibility to amoxycillin/clavulanic acid was comparable with that to gentamicin. The susceptibility of the Streptococcus and Staphylococcus isolates to amoxycillin/clavulanic acid was significantly much higher than that to oxacillin, gentamicin and ampicillin: 93 per cent of the Streptococcus isolates (62.7 per cent of the Pneumococcus isolates) and 90.7 per cent of the Staphylococcus isolates.     

A clinico-laboratory assessment of the efficacy of an Augmentin suspension in treating children with suppurative-inflammatory diseases caused by opportunistic bacteria]

Augmentin suspension (amoxycillin+clavulanic acid) was estimated in clinico-laboratory studies with respect to children suffering from pyoinflammatory diseases of various localization and its high efficacy was shown. Good and satisfactory results were recorded in 96.3 per cent of the cases in the treatment (monotherapy) and afterwards in the patients, adverse reactions such as nausea and vomiting being recorded only in 1 patient. The therapy with augmentin led to normalization of the microflora of the upper respiratory tract mucosa and a 1.5-fold increase in the neutrophil engulfment index.     

Augmentin in the clinical picture of infectious diseases]

Augmentin is a new combination manufactured by Smith Kline Beecham (Great Britain). It is composed of amoxycillin and clavulanic acid and has antibacterial activity. Augmentin was used in clinical trials in the therapy of 50 adult patients with suppurations after surgical operations on the organs of the abdominal cavity, general staphylococcal infections, pneumonia and prophylactically during the preoperative period. It was also used in the treatment of 30 children patients with bronchopulmonary affections and inflammatory otorhinolaryngological diseases. The clinical trials were performed in the Clinic of Infectious Diseases of the N. G. Gabrichevski? Moscow Research Institute of Epidemiology and Microbiology. For comparison ampicillin was used in the trials. Augmentin was shown to be an efficient formulation with antibacterial activity which could be successfully used in the parenteral therapy of severe affections due to organisms sensitive to it. In the treatment of the children patients with pneumonia augmentin by its therapeutic efficacy proved to be superior to ampicillin. The tolerance of augmentin was good.     

Treatment of subclinical mastitis in Damascus goats during lactation

This study was carried out to determine the efficacy of three treatment protocols for subclinical mastitis during lactation in Damascus goats. For this purpose intramammarian ampicillin dicloxacillin, intramuscular amoxycillin clavulonic acid and the combination of intramammarian ampicillin dicloxacillin and intramuscular amoxycillin clavulonic acid were used in goats with subclinical mastitis during lactation.The microbiological treatment rates in the intramammarian ampicillin dicloxacillin, intramuscular amoxycillin clavulonic acid and the combination of intramammarian ampicillin dicloxacillin and intramuscular amoxycillin clavulonic acid groups in the 7th and 21st days after the treatment were 62.5% and 92.5%, 62.5% and 70%, 87.5% and 87.5%, respectively. The intramammarian and intramuscular combination group was found to have a statistically higher treatment rate than other two groups on the 7th day. On the 21st day intramammarian and combination groups were found to have statistically better treatment rates than that of intramuscular group.It was concluded that the goat subclinical mastitis could be successfully treated during lactation. While the intramammarian ampicillin dicloxacillin treatment had the best treatment rates, the combination of intramuscular amoxycillin clavulonic acid was also successful. Intramuscular amoxycillin clavulonic acid as the sole treatment was not as effective as intramammarian therapy.     

Effectiveness of tobramycin in young children with Salmonella infection

The intestinal form of salmonellosis caused by S. typhimurium and the host immunity were studied in 108 infants. 60 infants were treated with ampicillin and the other 48 infants with tobramycin. The recovery period in patients treated with tobramycin was 8 days less as compared to the patients treated with ampicillin After discontinuation of the tobramycin use the pathogen was not detected in the repeated platings. Bactericidal function of neutrophils in these patients returned to normal within 15 days after the beginning of the treatment. Tobramycin was shown to be a highly active antibiotic in the treatment of salmonellosis of infants. No side effects were observed.     

Amoxycillin and Ampicillin

In vitro antibacterial activities of ampicillin and amoxycillin were compared against pigmented and non-pigmented strains of Serratia marcescens. Ampicillin appeared more effective than amoxycillin; three-fourths of all strains consistently exhibited an ampicillin minimum inhibitory concentration (MIC) of at least one tube less than that recorded for amoxycillin. Complete cross resistance was not observed as has previously been inferred. Further, greater bactericidal activity was demonstrated with ampicillin; minimum bactericidal concentrations (MBC) were either the same as or one tube greater than the MIC. MBCs for amoxycillin, however, were significantly higher; often four to five times greater than the MIC. Ampicillin exhibited greater bactericidal activity as inferred from differences observed in the biological lesions induced, as recorded through observations by scanning electron microscopy (SEM). Spheroplasts were the predominant morphological alteration induced by ampicillin. In contrast, only filament formation, which demonstrated a degree of reversibility, was induced by amoxycillin.     

Occurrence and antibiotic sensitivity of Enterobacteriaceae isolated from a group of Jordanian patients with community acquired urinary tract infections

The type and antibiotic sensitivity of urinary tract pathogens may differ in various communities. Of 207 isolates recovered from midstream urine specimens collected from a group of patients with community acquired urinary tract infections (UTI), 86% were species of Enterobacteriaceae. The most frequently recovered pathogens were Escherichia coli (82%), Klebsiella spp. (7.3%), Proteus spp. (6.2%), Enterobacter spp. (3.4%) and Citrobacter spp. (1.1%). High rates of resistance were found against ampicillin (95%), tetracycline (86%), carbenicillin (84%), trimethoprim/sulphamethoxazole (48%), and amoxycillin/clavulanic acid (45%). For the antibiotics tobramycin, aztreonam, ceftriaxone and gentamicin 7% of the isolates were resistant, while resistance varied from 9-18% for amikacin, ciprofloxacin, norfloxacin, nalidixic acid and cefuroxime. The incidence of UTI caused by Enterobacteriaceae was three times higher in females than in males, particularly in young and middle age groups (< or = 19 and 20-39 years).     

Efficacy of monotherapy by meropenem in ventilator-associated pneumonia]

We performed a prospective, open label, randomized study in intensive care unit patients with ventilator-associated pneumonia (VAP) to determine the efficacy and safety of empiric intravenous (i.v.) meropenem monotherapy compared with the combination of ceftazidime plus amikacin. A total of 140 patients receiving mechanical ventilation and diagnosed with pneumonia were included in the study. Patients were randomized to receive either 1 g meropenem i.v. every 8 hours or 2 g ceftazidime i.v. every 8 hours plus 15 mg/kg amikacin daily, administered to patients with normal renal function as two daily doses. Satisfactory clinical responses (cure or improvement) were achieved at the end of treatment in 68.1% of meropenem-treated patients and 54.9% in the ceftazidime/amikacin treated group (relative risk 1.25; 95% confidence interval > 1.00, 1.55). When non-evaluable patients were excluded from the analysis, the satisfactory clinical response was 82.5% and 66.1% for the meropenem and ceftazidime/amikacin patients, respectively (p = 0.044). Logistic regression demonstrated that treatment with meropenem and both the basic traumatic and medical pathologies were significantly associated with a satisfactory response. Adverse events judged to be possible or probably related to treatment were reported by seven (10.1%) patients in the meropenem group and by eight patients (11.3%) in the ceftazidime/amikacin group. The results of this study confirm that monotherapy with meropenem is well tolerated and provides superior efficacy to the conventional combination of ceftazidime and amikacin in combating VAP.     

Efficacy of levofloxacin (Tavanic) in the treatment of children with chronic pulmonary diseases]

The efficacy of the fluoroquinolone levofloxacin in the treatment of 35 children with bronchopulmonary disease exacerbation was practically the same as that of amoxycillin/clavulanate, cefotaxime or ceftriaxone. The clinical and bacteriological results were favourable. The eradication of the pathogens responsible for the bronchopulmonary inflammations in 86% of the patients was stated. There is no doubt that fluoroquinolones should not be widely used in pediatrics. They should be considered as reserve drugs for the treatment of severe cases when the routine agents fail. Their use is justified when the situation is risky and the data on the pathogen susceptibility to the drugs are available. Still, levofloxacin is the most safe fluoroquinolone with low hepatotoxicity and lower effect on the central nervous system. The episodes of its negative cardiovascular action are less frequent. Moreover, the most frequent side effects of fluoroquinolones such as nausea, diarrhea or vomiting are less frequent with the use of levofloxacin. No signs of arthropathy in the patients treated with levofloxacin were observed in our trial.     

Evaluation of three antibiotic programs in newborn infants.

Emergence of gram-negative bacteria resistnant to a number of antibiotics in intensive care nurseries for neonates emphasizes the need for alternatives in antibiotic combinations. One commonly used combination, gentamicin-ampicillin, and two newer combinations, tobramycin-cephalothin and amikacinampicillin, were evaluated prospectively in 60 newborns in such a nursery. Subjects were randomly assigned to one of the above therapy groups. Dosages in mg/kg.d were 100 for ampicillin and cephalothin, 6 for gentamicin and tobramycin and 15 for amikacin. Aminoglycoside serum concentrations, clinical tolerance and toxicity were monitored. Aminoglycoside concentrations after intravenous administration of the drugs were within the expected range (gentamicin and tobramycin 4 to 6 microgram/mL and amikacin 15 to 20 microgram/mL). There was no hematologic, renal or hepatic toxicity attributable to antibiotic therapy and the combinations were tolerated equally; no bilirubin displacement was detected in vitro or in vivo.     

Susceptibility of Arcobacter butzleri isolates to 23 antimicrobial agents

AIMS: The objective of this study was to determine the susceptibility of Arcobacter butzleri isolates to various antimicrobial agents used in the treatment of infectious diseases in humans and animals. METHODS AND RESULTS: Thirty-nine A. butzleri strains isolated from broiler chickens were tested for their susceptibility to 23 antimicrobial agents using a disc diffusion method. All isolates were resistant to aztreonam, cefuroxime sodium, cephalothin, orbenin, oxacillin, penicillin G and trimethoprim/sulphamethoxazol. Of the 39 isolates tested, 26 were also found resistant to amoxycillin, amoxycillin/clavulanic acid and ampicillin. One isolate was resistant to, and four showed intermediate level of resistance to, erythromycin. All isolates were susceptible to amikacin, chloramphenicol, danofloxacin, enrofloxacin, nitrofurantoin, nalidixic acid, tetracyclines and tobramycin. CONCLUSIONS: The majority of the isolates were found resistant to antibiotics commonly used for the treatment of infectious bacterial diseases in humans and animals. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows that A. butzleri strains vary in their resistance to certain kinds of antibiotics and caution should be taken when choosing a suitable antibiotic for the treatment of disease(s) caused by this organism.     

Ceftazidime does not enhance cyclosporin-A nephrotoxicity in febrile bone marrow transplantation patients

Ceftazidime was used as monotherapy for 30 febrile episodes in 28 patients, who underwent allogeneic bone marrow transplantation and who were treated concomitantly with the immunosuppressive agent cyclosporin-A. Ceftazidime did not enhance the well established nephrotoxicity of cyclosporin-A as measured by serum creatinine levels or creatinine clearance. Although an increasing number of Gram-positive infections in these patients warrants vigilance, ceftazidime as initial empirical monotherapy proved to be successful in 95% of all febrile post-transplantation patients. All Gram-negative and 69% of the Gram-positive infections were cured with ceftazidime alone. The overall clinical cure rate was 72%, with microbiological clearance in 63%. This compares favourably with aminoglycoside containing schedules and avoids the aminoglycoside associated nephrotoxicity.     

Amoxycillin: A new Semi-synthetic Penicillin

Amoxycillin (α-amino-p-hydroxybenzylpenicillin) is a new semi-synthetic penicillin with a broad spectrum of antibacterial activity similar to that of ampicillin. Penicillin-sensitive strains of staphylococci, streptococci, and pneumococci were sensitive to concentrations of 0·1 μg or less of amoxycillin/ml. Strains of Haemophilus influenzae were inhibited by a level of 0·5 μg/ml, and most strains of Escherichia coli, Proteus mirabilis, Shigella sonnei, Salmonella species, and Streptococcus faecalis were sensitive to a concentration of 5 μg or less of amoxycillin/ml. Penicillinase-producing strains of Staphylococcus aureus and strains of Pseudomonas aeruginosa, indole-positive Proteus, Klebsiella, and Enterobacter were insensitive to amoxycillin. The new penicillin was bactericidal in activity, as with other penicillins, and its antibacterial activity was not reduced in the presence of serum. After oral administration to volunteer subjects amoxycillin produced serum concentrations twice as high as those obtained with similar doses of ampicillin, and the penicillin was recovered unchanged in high concentrations in the urine. The absorption of amoxycillin was not greatly influenced by food, and administration of probenecid resulted in increased and more prolonged concentrations of amoxycillin in serum.     

Determination of ampicillin and amoxycillin by flow injection chemiluminescence method based on their enhancing effects on the luminol–periodate reaction

In this work, a new flow injection chemiluminescence method is described for the determination of ampicillin and amoxycillin. The method is based on the strong enhancing effects of these antibiotics on the luminol–periodate reaction. The present method allows the measurements of ampicillin in the range 0.02–1.0 mg/L range and amoxycillin in the range 0.1–10.0 mg/L range with the relative standard deviations within 0.8–2.0%. The sampling frequency was calculated about 90/h. The method was successfully applied to the determination of ampicillin and amoxycillin in pharmaceutical preparations. A brief discussion on the possible chemiluminescence reaction mechanism is presented. Copyright © 2003 John Wiley & Sons, Ltd.     

Typhoid outbreak in Kingston,Ont: experience with high-dose oral ampicillin.

Twenty-four children contracted typhoid fever at a summer camp near Kingston, Ont. Six were treated with chloramphenicol alone and 15 with high doses of ampicillin (300 mg/kg-d) by mouth. Ampicillin in this dosage was well tolerated except in three children in whom severe urticarial rashes developed and two who had significant diarrhea. However, high-dose oral ampicillin therapy had no advantage over that with lower doses or over chloramphenicol as judged by the rate of defervescence after the start of treatment, the rate of clinical relapse and the frequency of excretion of Salmonella typhi during convalescence.     

Rational use of antibiotics in mucoviscidosis pediatric cases with an account of local microbiological monitoring]

The results of local microbiological monitoring of bronchial secretion in 482 children with mucoviscidosis observed within 2000-2004 in the Republican Centre of Mucoviscidosis are presented. The results provided development of recommendations for rational use of antibiotics in the treatment of infectious processes in pediatric patients with mucoviscidosis. Since the emergence of MRSA in such patients is low, it is recommended to use antistaphylococcal betalactams (oxacillin, cefazolin, amoxycillin/clavulanate) for the treatment of infections due to S. aureus. For the treatment of infections due to some other pathogens, except S. maltophilia, the most active betalactams were carbapenems (imipenem and meropenem). Ciprofloxacin was active against numerous etiological agents causing low respiratory tract infections in children with mucoviscidosis except S. maltophila and A. xylosoxidans subsp. xylosoxidans. For the treatment of infections due to P. aeruginosa, P. aeruginosa muc. and K. pneumoniae the most active aminoglycosides were amikacin and tobramycin (for P. aeruginosa and P. aeruginosa muc.), while gentamicin was not active in such cases. As for antibiotics of other groups, high activity against S. aureus in the treatment of children with mucoviscidosis was recarded with the use of vancomycin, fusidic acid and rifampicin. Azithromycin and co-trimoxazole were active against H. influenzae. Chloramphenicol was active against S. maltophilia, B. cepacia and H. influenzae in the treatment of such patients.     

Comparative analysis of antibiotic sensitivity of Streptococcus pneumoniae strains isolated from patients and carriers

The data on antibiotic sensitivity of 38 strains of S. pneumoniae isolated from children and 46 strains isolated from carriers are presented. The isolates from the carriers had significantly higher sensitivity to benzylpenicillin, ampicillin, methicillin, oxacillin, cefazolin, erythromycin, oleandomycin and lincomycin. Resistance to gentamicin was more frequent in the strains isolated from the carriers. Among the strains of S. pneumoniae isolated from the patients and carriers representatives of serovar K19 were more frequent. There were no statistically reliable difference in them by sensitivity to benzylpenicillin, ampicillin, cefazolin, lincomycin and rifampicin. Still, the isolates from the carriers were much more sensitive to methicillin, oxacillin, oleandomycin and erythromycin.