A pilot study of single-dose azithromycin versus three-day azithromycin or single-dose ceftriaxone for uncomplicated acute otitis media in children

BACKGROUND

The pharmacokinetic profile of azithromycin supports its use as single-dose therapy for uncomplicated acute otitis media (AOM) in children.

OBJECTIVE

This study was designed to (1) compare the safety of single-dose oral azithromycin, 3 daily doses of oral azithromycin, and a single dose of intramuscular ceftriaxone for the treatment of uncomplicated AOM in children, and (2) provide preliminary efficacy data to support initiation of a larger, comparative trial of single-dose azithromycin for the treatment of uncomplicated acute otitis media in children.

METHODS

In this single-center pilot study, children with uncomplicated AOM were randomly assigned to receive single-dose oral azithromycin (30 mg/kg), 3-day oral azithromycin (10 mg/kg once daily), or single-dose intramuscular ceftriaxone (50 mg/kg). Tympanocentesis was performed before administration of the first dose, and clinical response was assessed on days 14-15 and 28-30.

RESULTS

Between September 1995 and May 1997, 198 children (mean age, 2.5 years) were enrolled. All of the patients were evaluable for the safety and clinical intent-to-treat (ITT) analyses, and 98 were evaluable for the microbiologic ITT analysis. On day 14-15, rates of clinical success (cure or improvement) for the 3 treatment groups were: 62/64 (97%) for single-dose azithromycin, 60/63 (95%) for 3-day azithromycin, and 61/62 (98%) for single-dose ceftriaxone. On day 28-30, the corresponding clinical success rates were 61/65 (94%), 61/66 (92%), and 62/64 (97%). For the 98 microbiologically evaluable patients, clinical success rates at day 14-15 were 28/30 (93%) for single-dose azithromycin, 31/35 (89%) for 3-day azithromycin, and 33/33 (100%) for single-dose ceftriaxone. On day 28-30, the corresponding clinical success rates were 27/30 (90%), 30/35 (86%), and 32/33 (97%). Treatment-related adverse event rates for single-dose azithromycin, 3-day azithromycin, and single-dose ceftriaxone were 10.6%, 9.1%, and 9.1%, respectively.

CONCLUSION

In this pilot study comparing single-dose azithromycin, 3-day azithromycin, and single-dose ceftriaxone for the treatment of uncomplicated AOM in children, no differences were detected among the 3 regimens.

Safety and immunogenicity of one dose of MenACWY-CRM, an investigational quadrivalent meningococcal glycoconjugate vaccine, when administered to adolescents concomitantly or sequentially with Tdap and HPV vaccines

This Phase III study evaluates an investigational quadrivalent meningococcal CRM(197) conjugate vaccine, MenACWY-CRM (Novartis Vaccines), when administered concomitantly or sequentially with two other recommended adolescent vaccines; combined tetanus, reduced diphtheria and acellular pertussis (Tdap), and human papillomavirus (HPV) vaccine. In this single-centre study, 1620 subjects 11-18 years of age, were randomized to three groups (1:1:1) to receive MenACWY-CRM concomitantly or sequentially with Tdap and HPV. Meningococcal serogroup-specific serum bactericidal assay using human complement (hSBA), and antibodies to Tdap antigens and HPV virus-like particles were determined before and 1 month after study vaccinations. Proportions of subjects with hSBA titres > or =1:8 for all four meningococcal serogroups (A, C, W-135, Y) were non-inferior for both concomitant and sequential administration. Immune responses to Tdap and HPV antigens were comparable when these vaccines were given alone or concomitantly with MenACWY-CRM. All vaccines were well tolerated; concomitant or sequential administration did not increase reactogenicity. MenACWY-CRM was well tolerated and immunogenic in subjects 11-18 years of age, with comparable immune responses to the four serogroups when given alone or concomitantly with Tdap or HPV antigens. This is the first demonstration that these currently recommended adolescent vaccines could be administered concomitantly without causing increased reactogenicity.

An open-label, double tympanocentesis, single-center study of trimethoprim sulfametoxasole in children with acute otitis media

Trimethoprim sulfamethoxasole has been recommended for the treatment of acute otitis media. In this double tympanocentesis study, children aged 3 to 48 months with acute otitis media received trimethoprim sulfamethoxasole twice daily (40 mg/kg/d) for 10 days. All children had a baseline tympanocentesis and in culture-positive children, tympanocentesis was repeated at the on-therapy visit. Of 89 children enrolled, 51 (57%) were clinically and bacteriologically evaluable. Bacteriologic eradication was achieved in 80% (42 of 52) of children, and overall clinical response at the end of therapy was 78%. Clinical success was 69% for culture-positive children versus 91% for culture-negative children at baseline tympanocentesis (P = 0.03). In this study, trimethoprim sulfamethoxasole clinical response was unsatisfactory, especially among culture-'positive children.

In vitro activities of levofloxacin and comparable agents against middle ear fluid, nasopharyngeal, and oropharyngeal pathogens obtained from Costa Rican children with recurrent otitis media or failing other antibiotic therapy

This study analyzes the in vitro activities of levofloxacin and other commonly used antimicrobials against middle ear fluid, nasopharyngeal, and oropharyngeal pathogens obtained from children with otitis media at risk of having a resistant pathogen. Levofloxacin proved to be very active against these pathogens and had intermediate activity against Streptococcus pyogenes.

Emergence of Penicillin‐NonsusceptibleStreptococcus pneumoniaeClones Expressing Serotypes Not Present in the Antipneumococcal Conjugate Vaccine

BACKGROUND

Penicillin-nonsusceptible Streptococcus pneumoniae isolates are confined mainly to a few serogroups. Capsular transformation may serve as a mechanism for spreading antibiotic resistance to new serotypes.

METHODS

Antibiogram and molecular typing, by pulsed-field gel electrophoresis (PFGE), were performed on 46 nasopharyngeal and middle ear fluid (MEF) isolates expressing serotype 11A, 45 MEF isolates expressing serotype 15B/C (recovered during 1998-2003 from Israeli children <5 years old), and 57 MEF isolates expressing serotype 19F (recovered during 1998-2001 from Costa Rican children <7.5 years old).

RESULTS

PFGE patterns showed that 49 (86%) of 57 serotype 19F isolates and 19 (41%) of 46 serotype 15B/C isolates were closely related. The vast majority of these isolates (80% of serotype 19F and 100% of serotype 15B/C isolates) were nonsusceptible to penicillin. Multilocus sequence typing (MLST) data show that the serotype 15B/C isolates belonged to the ST346 cluster, whereas the serotype 19F isolates were a single-locus variant of ST346. For serotype 11A isolates, PFGE patterns and MLST analysis showed that 8 (80%) of the 10 penicillin-nonsusceptible isolates belonged to a single clone--namely, ST156--which was identical to the international Spain9V-3 clone.

CONCLUSIONS

Penicillin-nonsusceptible pneumococcal clones of serotypes not related to those included in the 11-valent conjugate vaccines may derive from capsular transformation of vaccine-related serotypes. Of particular concern was the detection of serotype 11A variants of the successful international Spain9V-3 clone. This phenomenon, although seemingly rare at present, can have implications for the long-term effectiveness of the conjugate vaccines.

Single dose azithromycin for the treatment of uncomplicated otitis media

Three clinical trials have examined the efficacy and safety of single dose azithromycin (30 mg/kg) in children with uncomplicated acute otitis media (AOM). In the first trial, a small pilot study, the clinical and microbiologic efficacy of single dose azithromycin was comparable with that of 3-day azithromycin or single dose ceftriaxone. A second, non-comparative trial confirmed the clinical and microbiologic efficacy of the single dose regimen. The third study, a large double blind, double dummy trial, demonstrated comparable clinical success rates between single dose azithromycin and 10-day standard amoxicillin/clavulanate. The incidence of drug-related adverse events in patients treated with single dose azithromycin was low in all three trials and similar to rates that have been reported for other antimicrobial agents used for the treatment of patients with AOM. In the amoxicillin/clavulanate trial, compliance with single dose azithromycin was significantly better than with the amoxicillin/clavulanate regimen (P < 0.001). We conclude that a single dose of azithromycin (30 mg/kg) is safe and effective for the treatment of uncomplicated AOM in children.

Microbiology of otitis media in Costa Rican children, 1999 through 2001

BACKGROUND

Because of the increasing number of resistant middle ear pathogens and the impact of the new conjugate Streptococcus pneumoniae vaccine, an active surveillance of the microbiology and susceptibility pattern of middle ear pathogens is required.

OBJECTIVE

To study the microbiology and susceptibility pattern of middle ear pathogens obtained from Costa Rican children with acute otitis media (AOM), recurrent otitis media (ROM) and therapeutic failure otitis media (FOM).

METHODS

Between 1999 and 2001 middle ear fluid (MEF) was collected from 276 Costa Rican patients. S. pneumoniae serotyping and pulsed field gel electrophoresis analysis was done on available strains.

RESULTS

Among the total study population, 102 were AOM patients, 98 were ROM patients and 76 were FOM patients. Overall S. pneumoniae (88 strains) was the most common pathogen isolated followed by Haemophilus influenzae (41 strains) and Streptococcus pyogenes (10 strains). H. influenzae was the most common agent in FOM patients (P = 0.015). Beta-lactamase production was observed in 3 of 41 (7%) H. influenzae strains and 3 of 3 (100%) Moraxella catarrhalis strains. Penicillin-nonsusceptible S. pneumoniae strains were more common in FOM (64%) and ROM (63%) patients than in AOM (42%) patients (P = 0.05). S. pneumoniae serotype 19F was the most prevalent serotype, mainly within one distinct clone.

CONCLUSIONS

Overall S. pneumoniae serotype 19F was the most common isolate from the middle ear fluid of Costa Rican children. Beta-lactamase-negative H. influenzae was the most prevalent in the subpopulation of patients with FOM. S. pyogenes was the third most common isolate and M. catarrhalis was uncommon.

Microbiology of acute otitis media in Costa Rican children

BACKGROUND

Because of the increasing number of resistant middle ear pathogens reported from different centers worldwide, an active surveillance of the microbiology and susceptibility pattern of middle ear pathogens is required for proper antimicrobial recommendations among different regions of the world.

OBJECTIVE

To study the microbiology and susceptibility pattern of middle ear pathogens obtained from Costa Rican children with acute otitis media.

METHODS

Between 1992 and 1997 a diagnostic tympanocentesis was performed in 398 Costa Rican patients with acute otitis media. Middle ear fluid was obtained for culture and minimal inhibitory concentrations were determined by the E-test technique in those isolates obtained between October, 1995, and January, 1997.

RESULTS

The most common pathogens cultured were Streptococcus pneumoniae (30%), Haemophilus influenzae (14%), Staphylococcus aureus (4%) and Streptococcus pyogenes (4%). Moraxella catarrhalis was uncommon. Beta-lactamase production was low (3.7%) among the H. influenzae isolates but frequent among the Staphylococcus aureus (57.1%) and M. catarrhalis (100%) strains. Overall 9 of 46 S. pneumoniae isolates (19.6%) exhibited decreased susceptibility to penicillin of which 8 isolates (17.4%) showed intermediate and one strain (2.2%) high level resistance. Among the penicillin-susceptible S. pneumoniae isolates, susceptibility to the following antimicrobials was: 81%, azithromycin; 89%, clarithromycin; and 100%, ceftriaxone and trimethoprim-sulfamethoxazole (TMP-SMX). Among the penicillin-resistant S. pneumoniae isolates the percentage of susceptible strains was 89% for azithromycin, clarithromycin and ceftriaxone and 67% for TMP-SMX.

CONCLUSIONS

Based on this microbiologic information the agents considered first line drugs in the treatment of acute otitis media in Costa Rica remain amoxicillin or TMP-SMX.

Comparative trial of 3 days of azithromycin versus 10 days of clarithromycin in the treatment of children with acute otitis media with effusion

The authors compared the efficacy, safety and tolerance of azithromycin and clarithromycin in pediatric patients with acute otitis media. A randomized, open clinical trial was performed comparing azithromycin and clarithromycin in children aged 6 months to 12 years of age with acute otitis media with effusion. Patients were allocated to azithromycin at 10 mg/kg once daily for 3 days or to clarithromycin at 15 mg/kg day divided into two equal doses for 10 days. Clinical examinations and tympanometric evaluations were performed at baseline, day 3-5, day 10-14, day 28-30 and day 50-60. Tympanocentesis fluid cultures were collected at enrollment and urine and blood samples were obtained at baseline and day 10-14. Of 100 patients enrolled, 97 were considered evaluable. The most common middle ear pathogens were Streptococcus pneumoniae (60%), Haemophilus influenzae (15%) and Staphylococcus aureus (13%). Fifty patients (100%) treated with azithromycin and 45 (95.7%) patients treated with clarithromycin had a satisfactory clinical response. Rates of persistence of middle ear effusion and possible drug related side effects were comparable. Based on the efficacy and safety results, azithromycin for 3 days and clarithromycin for 10 days are considered to represent an attractive alternative for the treatment of children with acute otitis media.

An open, multicenter clinical trial of piperacillin/tazobactam in the treatment of pediatric patients with intra-abdominal infections

A total of 60 children with secondary peritonitis were enrolled in an open, non-comparative multicenter study designed to evaluate the safety, tolerance and efficacy of parenteral piperacillin/tazobactam (80/10 mg/kg every 8 hours) in young children. The most common diagnosis was perforated appendicitis (90%) and the three most common pathogens, obtained from the peritoneal cavity, were Escherichia coli (52 isolates), Pseudomonas aeruginosa (16 isolates) and Bacteroides sp. (19 isolates). Patients were examined daily during therapy, 4-14 days and 4-6 weeks post-therapy. Of the 60 patients, 43 were evaluable. The majority of patients had polymicrobial infections (36 patients). All the aerobic isolates were susceptible to piperacillin/tazobactam while 19 were resistant to piperacillin alone. Four of 43 clinically evaluable patients were considered a clinical failure and 3 of 40 bacteriologically evaluable patients were considered to have an unfavorable microbiological response. There were 2 clinically adverse events considered related to the study drug and several possibly related, mild and transitory, abnormalities in eosinophil counts and liver function tests. Based on the safety and efficacy results from this study, the advantages of using a single agent for the treatment of mixed infections of the peritoneal cavity and its potential activity against resistant organisms, we believe that further comparative clinical trials in children with intra-abdominal infections are warranted.

Antimicrobial therapy for children with chronic suppurative otitis media without cholesteatoma

This study was designed to determine the middle ear bacterial pathogens, the frequency of serum immunoglobulin deficiency and the efficacy of medical management in patients with chronic suppurative otitis media without cholesteatoma. This was an open noncomparative clinical trial performed at the National Children's Hospital, San Jose, Costa Rica, and included 186 patients older than 2 months of age with a confirmed diagnosis of chronic suppurative otitis media without cholesteatoma. Middle ear cultures and serum for immunoglobulin determinations were obtained on admission. The first 40 patients were treated only with ceftazidime and from patient 41 and up, if a Gram-positive organism was cultured, oxacillin was added to (for combined infection) or replaced ceftazidime. Parenteral antibiotics and suction twice daily were continued until three days after the middle ear became dry. Trimethropimsulfamethoxazole prophylaxis was administered during the follow-up period. Middle ear bacterial cultures were positive in 166 patients. Pseudomonas sp. (35.6%), enteric Gram-negative organisms (28.7%) and Gram-positive cocci (26%) were the most common organisms. Immunoglobulin determinations were below normal in 3 of 69 (4.3%) evaluable patients. Dryness of the ear was achieved in 174 patients (93.5%) including 130 of 139 patients treated with ceftazidime, 28 of 28 patients treated with oxacillin and 14 of 14 patients treated with ceftazidime and oxacillin. Recurrent otorrhea developed in 39 (23.4%) patients. Twice-daily canal aspiration and parenteral ceftazidime for Gram-negative organisms and/or oxacillin for Gram-positive bacteria for 3 days after dryness of the middle ear followed by prophylactic oral antimicrobials are effective for treatment of most chronic suppurative otitis media without cholesteatoma patients.