[Detection of antibacterial activity in the urine of children: a comparison of three tests]

BACKGROUND

Detection of antibacterial activity in urine is important for the diagnosis of urinary tract infections and for assessment of patient compliance with antibiotic therapy.

METHOD

Urines of paediatric inpatients were examined by the Bacillus subtilis agar diffusion test and two commercial test strips (Micur BT and Urotest AB).

RESULTS

566 urines of 431 patients were examined. The B. subtilis agar diffusion test was the most reliable method (accuracy 98.8%). Micur BT showed a comparatively low specificity (87.6%) and Urotest AB had a comparatively low sensitivity (86.0%).

CONCLUSION

The B. subtilis agar diffusion test is the most reliable method for detection of antibacterial activity in the urine of children.

Evaluation of three methods for culturing alginate throat swabs from cystic fibrosis patients

Deep throat swabs are usually cultured for potential respiratory pathogens in patients with cystic fibrosis (CF) who do not produce sputum. Using alginate swabs, three methods were examined in the present study: (i) semiquantitative processing (direct plating); (ii) mere elution of swabs in Ringer's lactate followed by plating of the eluate; and (iii) complete quantitative processing (elution plus two-step dilution series). Throat swabs from 56 CF patients yielded 122 isolates of potential respiratory pathogens. Semiquantitative processing (n = 101 isolates) was not significantly inferior to elution (n = 104) and quantitative processing (n = 113; p > 0.05). Since semiquantitative processing is the simplest method, it is to be preferred, provided that alginate swabs are used.

Comparison of three media for agar dilution susceptibility testing of Bordetella pertussis using six antibiotics

Since antimicrobial susceptibility testing of the fastidious species Bordetella pertussis is not standardized, the most suitable medium for agar dilution testing of this species has not yet been determined. In the present study, Mueller-Hinton, Bordet-Gengou, and Oxoid charcoal agars (each supplemented with 5% horse blood) were evaluated for agar dilution susceptibility testing of Bordetella pertussis against ampicillin, chloramphenicol, ciprofloxacin, doxycycline, erythromycin, and trimethoprim-sulfamethoxazole. Mueller-Hinton agar was the most suitable medium.

In vitro susceptibilities of Bordetella pertussis and Bordetella parapertussis to two ketolides (HMR 3004 and HMR 3647), four macrolides (azithromycin, clarithromycin, erythromycin A, and roxithromycin), and two ansamycins (rifampin and rifapentine)

When tested by agar dilution on Mueller-Hinton agar supplemented with 5% horse blood, the ketolides HMR 3004 and HMR 3647 were slightly more active (MIC at which 90% of the isolates were inhibited [MIC90], 0.03 microg/ml) against Bordetella pertussis than azithromycin, clarithromycin, erythromycin A, and roxithromycin. Azithromycin (MIC90, 0.06 microg/ml) was the most active compound against B. parapertussis. Rifampin and rifapentine were considerably less active.

[Acute hematogenous osteomyelitis in childhood--correlation of clinical aspects, diagnostic parameters, therapy and prognosis]

BACKGROUND

Acute hematogenous osteomyelitis is a common disease in childhood. If treated early, conservative management is possible in most cases. During recent decades, clinical picture, diagnostic techniques and treatment have changed due to various reasons, e.g. previous antibiotic treatment. New laboratory tests and improved imaging techniques such as magnetic resonance imaging enable an earlier diagnosis and thus an earlier onset of treatment and improve the prognosis of hematogenous osteomyelitis. Outcome has also been improved by new antibiotics with enhanced activity against staphylococci.

METHOD

The records of 34 children aged 3 weeks to 172 months with acute hematogenous osteomyelitis were evaluated retrospectively. In some cases, the data were completed by phone calls with parents and family physicians. The results were compared with the current literature.

RESULTS AND CONCLUSIONS

If diagnosed and treated early, acute hematogenous osteomyelitis in childhood has a good prognosis. For primary diagnosis, the clinical picture, parameters of inflammation and magnetic resonance imaging or scintigraphy are useful. The course of the disease can be assessed by clinical signs and the erythrocyte sedimentation rate. Complications can be recognized by conventional radiography and sonography. Initial antibiotic treatment should be carried out parenterally for at least 3 weeks. An exclusively oral treatment is not recommended.

[Pertussis: current aspects of diagnosis, therapy and prevention]

Pertussis (whooping cough) may occur at any age. Beside the typical course of the disease in three stages, atypical courses are observed not infrequently, particularly in adults. In early pertussis, isolation of Bordetella pertussis from nasopharyngeal secretions is the diagnostic method of choice. The polymerase chain reaction is a promising, albeit still investigational diagnostic method. In longstanding cough, serology is the method of choice. Pertussis is treated with erythromycin in high doses for 2 weeks. For prevention of the disease, the new acellular vaccines are to be preferred.

Postal transport of sputa from cystic fibrosis patients does not decrease the microbiological yield

Ambulatory cystic fibrosis patients often submit sputum specimens by post. This study addressed the question if and how postal transport affects the microbiological results of sputum cultures from these patients. Thirty-two fresh sputa and 32 next-day sputa posted from home were cultured qualitatively and quantitatively. The numbers of isolates of potentially pathogenic species and the mean numbers of colony-forming units of these isolates grown from parallel specimens were statistically not different. It is concluded that-under the conditions of this study-postal transport of sputa from cystic fibrosis patients does not decrease the microbiological yield.

Efficacy of a two-component acellular pertussis vaccine in infants

OBJECTIVE

This case-control study investigated the protective efficacy against pertussis of three doses of a two-component acellular pertussis vaccine (manufactured by Biken in Japan) combined with diphtheria and tetanus toxoids (manufactured by Connaught Laboratories in the US) in infants.

METHODS

A case-control study was performed in 63 pediatric practices in Germany. Prospective recruitment of 16,780 infants ages 6 to 17 weeks took place between February, 1993, and July, 1994. According to parental choice infants received either Biken acellular pertussis vaccine combined with diphtheria and tetanus toxoids (DTacP) (74.6%) at approximately 2, 4 and 6 months of age, or a licensed German diphtheria-tetanus toxoids-whole cell pertussis vaccine (10.9%), diphtheria-tetanus toxoids vaccine (12.5%) or no vaccine (2.0%). Prospective surveillance of pertussis cases between February, 1993, and May, 1995, was accomplished by culturing all infants < or =2 years of age presenting with cough > or = 7 days. A pertussis case was defined as any cough of 21 days or longer plus a positive Bordetella pertussis culture or household contact exposure.

RESULTS

We identified 241 pertussis cases prospectively by 11,017 B. pertussis cultures and 949 controls matched for age were selected from the same pediatric practices. Medical history and demographic and vaccine status data were collected from each case and for four controls. Data were analyzed through conditional logistic regression taking into account individual matching and adjusting for potential confounding variables. DTacP combined with diphtheria and tetanus toxoids vaccine was 82% protective (95% confidence interval, 68 to 90), diphtheria-tetanus toxoids-whole cell pertussis vaccine was 96% protective (95% confidence interval, 78 to 99). Protection against typical B. pertussis infection characterized by paroxysmal cough lasting > or =21 days was 96% (95% confidence interval, 87 to 99) for DTacP and was 97% (95% confidence interval, 79 to 100) for diphtheria-tetanus toxoids-whole cell pertussis vaccine. Adjustment for potentially confounding variables did not change the results significantly.

CONCLUSIONS

Three doses of the two-component acellular pertussis vaccine protected infants against pertussis disease during the period before the recommended booster vaccination. For typical pertussis disease as defined by the WHO efficacy was high and similar to that of a licensed German diphtheria-tetanus toxoids-whole cell pertussis vaccine.

Comparison of Etest and agar dilution for testing the activity of three macrolides against Bordetella parapertussis

Agar dilution and Etest using Mueller-Hinton II agar supplemented with 5% whole defibrinated horse blood were compared for testing the activities of azithromycin, clarithromycin, and erythromycin against 34 clinical isolates of the fastidious species Bordetella parapertussis. There was good overall agreement (100.0% within +/- 1 log2 dilution step) between both methods. The Etest offers an excellent and convenient alternative to agar dilution for testing the activities of macrolides against B. parapertussis.

Treatment of oropharyngeal candidiasis in immunocompetent infants: a randomized multicenter study of miconazole gel vs. nystatin suspension. The Antifungals Study Group

BACKGROUND

Miconazole gel has previously been shown to be an effective treatment for oropharyngeal candidiasis (thrush) in immunocompetent infants. This study compares miconazole gel with the standard therapeutic agent, nystatin suspension, with regard to efficacy, optimal duration of therapy and safety.

DESIGN

Prospective multicenter, randomized, office-based open trial.

PATIENTS

Twenty-six pediatricians enrolled 227 immunocompetent infants with signs of oropharyngeal thrush. Subjects were randomly assigned to receive 25 mg of miconazole as oral gel four times daily or 100,000 IU of nystatin as suspension four times daily after meals. All subjects were evaluated for safety. Fifteen patients whose thrush was not confirmed by culture were excluded from further analysis. The remaining 212 subjects were entered into an intention-to-treat analysis. Another 29 patients violated the study protocol; the remaining 183 subjects were evaluated for efficacy (per protocol analysis).

RESULTS

Clinical cure by Day 5 of treatment was demonstrated in 84.7% of the 98 subjects in the miconazole group and 21.2% of the 85 subjects in the nystatin group (P < 0.0001). By Day 8, the cumulative clinical cure rates were 96.9% (miconazole) and 37.6% (nystatin), respectively (P < 0.0001). By Day 12.99.0% of subjects in the miconazole group and 54.1% of subjects in the nystatin group were clinically cured (P < 0.0001). Premature cessation of treatment at parents' request because of lack of clinical efficacy occurred in none of the infants treated with miconazole and in 6 infants treated with nystatin (P = 0.029). The oral yeast eradication rate on Day 5 was 54.1% with miconazole and 8.2% with nystatin (P < 0.0001). Clinical relapses of oropharyngeal thrush and side effects of the study drugs were observed with similar frequency in both study arms.

CONCLUSIONS

Miconazole gel was significantly superior to nystatin suspension with regard to efficacy, rapidity of achieving cure and oropharyngeal yeast eradication. Relapses and side effects did not occur more frequently with miconazole than with nystatin. The results of this study indicate that miconazole gel is superior to nystatin suspension as the treatment for oropharyngeal candidiasis in immunocompetent infants.

Retrospective analysis of yeast colonization and infections in paediatric bone marrow transplant recipients

Sixty-four paediatric patients who underwent allogeneic (n = 35), autologous (n = 28) or syngeneic (n = 1) bone marrow transplantation (BMT) between 1992 and 1994 were evaluated retrospectively. As antifungal prophylaxis, all patients received amphotericin B tablets and 62 of 64 (96.9%) received oral fluconazole. Weekly surveillance cultures revealed fungal colonization in 35 patients (54.7%). Six patients (9.4%) were colonized before BMT only, 17 (26.6%) after BMT only and 12 (18.8%) both before and after BMT. Candida albicans was the most frequently isolated fungus [21 of 46 fungal isolates (45.7%)], followed by C. glabrata [14 isolates (30.4%)]. Non-albicans species of Candida were most frequently isolated after BMT from the faeces, often in high numbers. Autologous marrow recipients had a higher fungal colonization rate both before and after BMT than allogeneic marrow recipients. One patient suffered from invasive pulmonary aspergillosis after BMT. No fungaemias or deep-seated yeast infections were observed. Six of the seven patients who had to be treated with intravenous amphotericin B because of antibiotic-refractory fever had undergone autologous BMT. Multivariate analysis of various parameters showed only pre-BMT yeast colonization to be independently associated with post-BMT colonization. Thus, systemic mycoses occurred only rarely in this study population; however yeast colonization after BMT (especially with non-albicans species) was a frequent event in spite of double prophylaxis with oral amphotericin B and fluconazole.

Rational prescribing of antibacterials in hospitalised children

The subject of this review is the rational prescribing of antimicrobial agents for the therapy of serious community-acquired infections in hospitalised infants and children. First, cost-containment strategies such as streamlining of antibacterial therapy, outpatient parenteral antibacterial therapy and sequential ('stepdown') therapy with parenteral followed by oral therapy are reviewed. In most of these areas, paediatric studies are scant or lacking. Then specific paediatric aspects of the choice of parenteral antibacterials such as penicillins, cephalosporins, aminoglycosides, macrolides and other agents are discussed. With particular reference to cost containment, rational treatment strategies for some serious bacterial infections such as meningitis, occult bacteraemia, endocarditis, osteomyelitis, arthritis, pyelonephritis, Lyme borreliosis (advanced stages) and pneumonia are proposed. In most of these disease, there is potential for cutting treatment costs and studies that compare these newer strategies with traditional treatment regimens are urgently needed.

Rational prescribing of antibacterials in ambulatory children

The rational prescribing of oral antimicrobial agents for bacterial infections in children who can be treated in an ambulatory setting is the subject of this review. First, restrictive use of antibacterials is advocated to avoid widespread development of bacterial resistance. The use of simple methods, suitable for office use, to discern viral from bacterial infections is recommended. Second, in selecting an antimicrobial agent, the physician should consider a number of distinctive features of each agent. Besides aspects of pharmacokinetics, antibacterial spectrum and tolerability, the number of daily doses and, of particular importance for children, the palatability of suspensions plays an important role in achieving patient compliance. Agents that can be administered once or twice daily and possess an agreeable taste in addition to proven efficacy, established tolerability and a reasonable price are to be preferred. Specific paediatric aspects in choosing among penicillins, cephalosporins, macrolides and other oral antibacterials are discussed. For pharmacoeconomic reasons, the optimal duration of antibacterial treatment and the role of short course therapy for various bacterial infections should be studied in more detail. Finally, rational antimicrobial treatment of common paediatric bacterial infections, such as streptococcal tonsillopharyngitis, acute otitis media, acute sinusitis, bacterial pneumonia, pertussis, Lyme borreliosis (early stage) and lower urinary tract infection is reviewed.

[Whooping cough in pregnant patients and newborn infants]

Pertussis affects not only children but also adults. The disease often takes an atypical course in adults and it is frequently misdiagnosed. Pregnant women with pertussis do not suffer from serious obstetrical complications. If, however, they are contagious at the time of delivery, they may infect the neonate immediately post partum. Neonates are susceptible to pertussis and may become seriously ill with potentially fatal consequences. Neonatal pertussis is frequently misdiagnosed, too. The disease can be prevented by prophylactical administration of erythromycin to the neonate.

In vitro susceptibilities of Bordetella pertussis and Bordetella parapertussis to four fluoroquinolones (levofloxacin, d-ofloxacin, ofloxacin, and ciprofloxacin), cefpirome, and meropenem

The in vitro activities of levofloxacin, ofloxacin, d-ofloxacin, ciprofloxacin, cefpirome, and meropenem against 34 clinical isolates each of Bordetella pertussis and Bordetella parapertussis were determined by agar dilution on Mueller-Hinton agar supplemented with 5% horse blood. Levofloxacin was as active as ciprofloxacin against both species (MIC, 0.06 microgram/ml) and more active than ofloxacin and d-ofloxacin. Cefpirome was more active against B. pertussis (MIC, 1.0 microgram/ml) than against B. parapertussis (MIC, > 2 micrograms/ml), while the reverse was true for meropenem (MIC, 2.0 micrograms/ml against B. pertussis and 1.0 microgram/ml against B. parapertussis).

Randomized comparison of two nystatin oral gels with miconazole oral gel for treatment of oral thrush in infants. Antimycotics Study Group

Recently, two commercial oral nystatin gels have been marketed in Germany (Candio-Hermal, Hermal; Lederlind, Lederle). In a prospective open randomized multicentre study involving 12 paediatricians in private practice, Candio-Hermal and Lederlind were compared with miconazole oral gel (Daktar, Janssen) in 95 infants with oral thrush (candidosis). Oral and rectal swabs were taken on days 0 and 14. Treatment duration varied according to the amount of drug contained in one tube (Candio-Hermal 10 days; Lederlind 14 days; Daktar 8 days). On day 14, clinical cure was observed in 23 of 27 infants treated with Daktar (85.1%), in 15 of 35 infants treated with Candio-Hermal (42.8%; p < 0.0007); and in 16 of 33 infants treated with Lederlind (48.5%; p < 0.004). Clinical relapses were observed in 15 patients (Candio-Hermal: n = 9; Lederlind: n = 6). The overall oral mycologic cure rate was significantly higher with Daktar (29.6%) and Candio-Hermal (20.0%) than with Lederlind (3.0%; p < 0.005 and < 0.03, respectively). It can be concluded that Daktar oral gel is significantly more effective than Candio-Hermal and Lederlind in curing oral thrush in infants.

Comparison of media for agar dilution susceptibility testing of Bordetella pertussis and Bordetella parapertussis

Antimicrobial susceptibility testing of the fastidious species Bordetella pertussis and Bordetella parapertussis is not standardized. In an attempt to find the optimal medium for agar dilution testing, the activity of erythromycin against Bordetella pertussis and Bordetella parapertussis (34 isolates each) was assessed using homologous broth/agar combinations of Bordet-Gengou, charcoal, Iso-Sensitest (Oxoid) and Mueller-Hinton media. Each medium was supplemented with 5% and 20% whole defibrinated horse blood. Mueller-Hinton medium supplemented with 5% horse blood performed best overall.