Evaluation of 3-day azithromycin or 5-day cefaclor in comparison with 10-day amoxicillin for treatment of tonsillitis in children.

To evaluate the clinical efficacy of azithromycin, cefaclor, and amoxicillin in treatment of pediatric tonsillitis, a total of 256 children with Group A ß-hemolytic streptococcus (GAS) tonsillitis were randomly divided into 3 groups. Only patients assessed with streptococcus-positive tonsillitis, considered to be compliant with treatment and complete clinical and microbiological evaluations at the end of therapy (day 14) and follow-up (day 30) were included in the efficacy analysis. Our study demonstrated that 96.4% of patients in the azithromycin group, 92.4% of patients in the cefaclor group, and 91.0% of patients in the amoxicillin group were recorded as clinical success at the end of therapy. Bacteriological eradication rates of the 3 groups at the end of therapy were 94.0%, 89.9%, and 88.5%, respectively. A pathogen recurrence rate was evaluated as 2.6%, 7.0%, and 5.9% at the follow-up. Treatment-stimulated adverse events occurred in 2.4% of patients in the azithromycin group, 11.3% in the cefaclor group, and 11.4% in the amoxicillin group. In summary, azithromycin showed an effective tendency for the treatment of pediatric tonsillitis with lower occurrence rate of adverse reactions, although there is no statistical significance for the clinical and bacteriological eradication efficacy between these 3 groups.

Concentrated platelet-rich plasma used in root canal revascularization: 2 case reports.

AIM: To present two case reports describing the treatment of immature teeth with necrotic pulps using concentrated platelet-rich plasma (cPRP) with 12-month clinical and radiographic follow-up. SUMMARY: Root canal revascularization was performed on immature permanent teeth clinically and radiographically diagnosed as requiring root canal treatment. Following disinfection of the canal space with triple antibiotic paste (1 : 1 : 1: ciprofloxacin, metronidazole and cefaclor), a tissue scaffold was created with cPRP prepared using 2-step centrifugation. The final restoration was completed with white mineral trioxide aggregate and composite resin. The patients were recalled for clinical and radiographic evaluations every 3 months. At the 12-month follow-up apical closure by narrowing of the apical foramen and convergence of the apical walls in the treated teeth was observed.

Analysis of cefaclor in novel chocolate-based camouflage capsules.

The determination of cefaclor in a new, complex chocolate matrix was performed by using a simple sample preparation (dispersion in dilute hydrochloric acid at 80 degrees C, centrifugation, washing with cyclohexane), followed by ion pair HPLC on a Kinetex pentafluorophenyl core-shell stationary phase with UV detection at 265 nm. We obtained good linearity (R2 = 0.9976) and precision (average RSD 0.86%) for the relevant concentration range. The preparations, although hand-made in this pilot phase, showed good uniformity of content. After being stored for four weeks in a refrigerator the preparation did not contain recognizable amounts of decomposition products.

[Suppurative Thrombophlebitis of the Posterior Neck Caused by Streptococcus constellatus: A Case Report and Literature Review].

We report a rare case of suppurative thrombophlebitis of the posterior neck caused by Streptococcus constellatus. A 69-year-old female patient was admitted to the hospital with neck pain and fever, which had persisted for 16 days prior to hospitalization. On day 1 (day of admission), blood cultures (later identifying S. constellatus) were performed, and ceftriaxone (CTRX) IV (2 g SID) was started. On day 3, suppurative thrombophlebitis of the posterior neck was diagnosed by CT scan. The antimicrobials were changed from CTRX to ampicillin/sulbactam IV (12 g QID) to guard against the possibility of complicated infection with Fusobacterium spp. or Prevotella spp. On day 17, a CT scan revealed that the thrombus remained. Therefore, oral edoxaban (30 mg SID) was started. On day 27, the patient was discharged after her medication was changed to oral amoxicillin/clavulanate (1500 mg/375 mg TID). On day 33, the amoxicillin/clavulanate was changed to oral cefaclor (1500 mg TID) and edoxaban was discontinued due to itching. On day 45, the course of cefaclor was completed. The patient went on to follow an uneventful course with no relapses or complications for two years since the conclusion of treatment. These results suggest that when a patient presents with persistent neck pain accompanied by fever, suppurative thrombophlebitis of the posterior neck should be considered. In antimicrobial therapy, the treatment could be switched from intravenous to oral. In addition, direct-acting oral anticoagulants may be an alternative to other forms of anticoagulants.

Evaluation of cefaclor oral suspensions stability using reversed phase high performance liquid chromatography and antimicrobial diffusion methods.

The effect of temperature stresses on Cefaclor suspensions under different storage conditions for a duration of 14 days was tested. The degradation of Cefaclor was determined on the 2nd, 7th and 14th day after reconstitution using a sensitive and precise Reversed phase High Performance Liquid Chromatographic (RP-HPLC) method. The RSD values for Forticef, Midocef, Ceclor, Cefabac and Cloracef, indicated a good precision of the RP-HPLC method. The limit of detection (LOD) and the limit of quantification (LOQ) were found 0.008 mg/ml and 0.03mg/ml respectively. The antimicrobial effect of Cefaclor suspension was also tested against pathogenic bacteria using the cylinder diffusion method. The RSD values range of the antimicrobial assay for all the Cefaclor compounds were 1.47-3.7%. The LOD and LOQ were 0.2mg/ml and 1mg/ml respectively. During the normal use of Ceclor, Midocef, and Forticef the loss of activity and the degradation were less than 5% on the 14th day of preservation at 4°C. However, the percentage of degradation for Cefabac and Cloracef on the 14th day reached 5 and 6%, respectively. Statistical multiple comparison between the effect of 4°C and 25°C indicated non significant mean differences (P>0.05) for Forticef, Cefabac, Ceclor and Cloraf and significant effect for Midocef (P <0.05). Significant effects were observed between (4oC and 37°C) and (25°C and 37°C) for all except Ceclor. Multiple comparisons between days of storage showed non significant mean difference values at 4°C except Cefabac. However significant results between days were found at 25°C and 37°C except for Midocef between (7th and 14th day). It was found that the pediatric suspensions of Cefaclor in the Jordanian market were stable and contained the amount of active ingredient specified by the United States pharmacopoeias specification (USP) and the British Pharmacopoeias specifications (BP).

Cefaclor Monohydrate-Loaded Colon-Targeted Nanoparticles for Use in COVID-19 Dependent Coinfections and Intestinal Symptoms: Formulation, Characterization, Release Kinetics, and Antimicrobial Activity.

Corona virus disease-2019 (COVID-19) emerged in Wuhan, China in December 2019 and was declared as a pandemic by the World Health Organization in March 2020. Although there is no complete treatment protocol for COVID-19, studies on this topic are ongoing, and it is known that broad-spectrum antibiotics such as cephalosporins are used for coinfections and symptoms in COVID-19 patients. Studies have shown that Staphylococcus aureus and Escherichia coli bacteria can cause symptoms such as diarrhea and coinfections accompanying COVID-19. Therefore, in this study, colon-targeted cefaclor monohydrate (CEF)-loaded poly(lactic-co-glycolic acid) (PLGA)-Eudragit S100 nanoparticles (NPs) were prepared using a nanoprecipitation technique. The particle sizes of the CEF-loaded NPs were between 171.4 and 198.8 nm. The encapsulation efficiency was in the range of 58.4%-81.2%. With dissolution studies, it has been concluded that formulations prepared with Eudragit S100 (E-coded) and Eudragit S100+PLGA (EP-coded) are pH-sensitive formulations and they are targetable to the colon, whereas the formulation prepared only with PLGA (P-coded) can release a higher CEF rate in the colon owing to the slow release properties of PLGA. The release kinetics were fitted to the Korsmeyer-Peppas and Weibull models. The antibacterial activity of E-, EP-, and P-coded formulations was 16-fold, 16-fold, and 2-fold higher than CEF, respectively, for S. aureus and E. coli according to the microdilution results. As a result of the time killing experiment, all formulations prepared were found to be more effective than the antibiotic itself for long periods. Consequently, all formulations prepared in this study hope to guide researchers/clinicians in treating both gram-positive and gram-negative bacteria-induced infections, as well as COVID-19 associated coinfections and symptoms.

Effects of cranberry juice on pharmacokinetics of beta-lactam antibiotics following oral administration.

Cranberry juice consumption is often recommended along with low-dose oral antibiotics for prophylaxis for recurrent urinary tract infection (UTI). Because multiple membrane transporters are involved in the intestinal absorption and renal excretion of beta-lactam antibiotics, we evaluated the potential risk of pharmacokinetic interactions between cranberry juice and the beta-lactams amoxicillin (amoxicilline) and cefaclor. The amoxicillin-cranberry juice interaction was investigated in 18 healthy women who received on four separate occasions a single oral test dose of amoxicillin at 500 mg and 2 g with or without cranberry juice cocktail (8 oz) according to a crossover design. A parallel cefaclor-cranberry juice interaction study was also conducted in which 500 mg cefaclor was administered with or without cranberry juice cocktail (12 oz). Data were analyzed by noncompartmental methods and nonlinear mixed-effects compartmental modeling. We conclude that the concurrent use of cranberry juice has no significant effect on the extent of oral absorption or the renal clearance of amoxicillin and cefaclor. However, delays in the absorption of amoxicillin and cefaclor were observed. These results suggest that the use of cranberry juice at usual quantities as prophylaxis for UTI is not likely to alter the pharmacokinetics of these two oral antibiotics.

Biodegradable microspheres based on gelatin-porcine mucin admixtures: in vitro and in vivo delivery studies.

Soluble mucus glycoprotein (S-mucin) processed from the small intestines (ileal region) of freshly slaughtered pigs via homogenization, dialysis, centrifugation and lyophilization and their admixtures with type B gelatin were used to prepare cefaclor-loaded microspheres by the emulsification-crosslinking method. The microspheres were evaluated for the in vitro delivery of cefaclor in both simulated intestinal fluid (SIF) without pancreatin (pH 7.4) and simulated gastric fluid (SGF) without pepsin (pH 1.2). Results obtained indicated that the microspheres formulated were highly mucoadhesive and that release of cefaclor in both release media was non-Fickian and was much higher and more rapid in SGF than in SIF and from microspheres based on gelatin alone when compared to those based on gelatin-procine mucin admixtures. The mean area under the plasma level versus time curves (AUC) was shown to be dependent on the formulation with values of 172.3 mug.h/ml for the control, 278.5 mug.h/ml for microspheres based on gelatin only and 353.0 mug.h/ml for microspheres formulated with equal parts of gelatin and mucin indicating that the rectal route may provide a therapeutically viable alternative to the oral route for the delivery of cefaclor. Further indications also emerged of a possibility of site-specific delivery of cefaclor to the small intestine through a careful selection of gelatin type and porcine mucin admixtures prior to formulation of the microspheres. On the whole, the inclusion of S-mucin in the composition of the microspheres had an enhancer effect on the release and rectal bioavailability of cefaclor which may be exploited in the design of a rectal delivery system of the drug.

Case report: pulp revascularization of a necrotic, infected, immature, permanent tooth.

The purpose of this report is to present the case of a patient wherein revascularization of the necrotic infected pulp space of an immature permanent maxillary central incisor tooth was induced in vivo by stimulation of a blood clot from the periapical tissues into the canal space. This was achieved after disinfecting the canal space with a topical antibiotic paste followed by inducing a blood clot scaffold from the periapical tissues. This treatment approach offers great potential to avoid the need for traditional apexification with calcium hydroxide or the need to achieve an artificial apical barrier with mineral trioxide aggregate. Furthermore, this treatment approach can help rescue infected immature teeth by physiologically strengthening the root walls.

Study on the efficacy of cefaclor for the treatment of asymptomatic bacteriuria and lower urinary tract infections in pregnant women with a history of hypersensitivity to penicillin.

PURPOSE: The purpose of this study was to compare the efficacy and safety profile of twice daily versus the conventional three daily intake of cefaclor administrated orally for five to seven days in the treatment of asymptomatic bacteriuria or acute cystitis in pregnant women with a history of hypersensitivity to penicillin. METHODS: Between August 2003 and August 2004, 63 pregnant women with a positive urine culture and a history of suspicion of hypersensitivity to penicillin were randomly divided into two groups. The women in the first group received 500 mg of cefaclor while those in the second group received 750 mg of cefaclor for five to seven days. Laboratory and clinical results were assessed a week and a month after complettion of the therapy. RESULTS: Final therapy (bacteriologic eradication) succeeded in 93.7% (30/32) of the first group and in 90.3% (28/31) of the second group. CONCLUSION: Dosage of cefaclor at 750 mg is as effective as conventional cefaclor at 500 mg and better tolerated.

Battling bacterial infection with hexamethylene diisocyanate cross-linked and Cefaclor-loaded collagen scaffolds.

Implant infections remain a major healthcare problem due to the prolonged hospitalisation period required to disrupt and treat bacterial biofilm formation, and the need for additional surgery to remove/replace the infected implant, which if not removed in a timely manner may lead to sepsis. Although localised drug administration, via an implanted scaffold, has shown promise in a clinical setting, the ideal scaffold cross-linking (to initially withstand the aggressive infection environment) and drug (to be effective against infection) have yet to be identified. In this work, in the first instance, the biochemical, biophysical, and biological properties of collagen sponges as a function of various concentrations (0.625%, 1.0%, 2.5%, 5.0%, and 10.0%) of hexamethylene diisocyanate were assessed. Data presented illustrate that hexamethylene diisocyanate at 0.625% concentration was able to effectively stabilise collagen scaffolds, as judged by the reduction in free amines, adequate resistance to collagenase digestion, reduction in swelling, increase in denaturation temperature, suitable mechanical properties, and appropriate cytocompatibility. Subsequently, collagen scaffolds stabilised with 0.625% hexamethylene diisocyanate were loaded with variable concentrations (0, 10, 100, and 500 µg ml-1) of Cefaclor and Ranalexin. Both drugs exhibited similar loading efficiency, release profile, and cytocompatibility. However, only collagen scaffolds loaded with 100 µg ml-1 Cefaclor exhibited adequate antibacterial properties against both 106 and 108 colony-forming units per ml of both Escherichia coli and Staphylococcus epidermidis.

Immunomodulatory properties of cefaclor: in vivo effect on cytokine release and lymphoproliferative response in rats.

The proper and coordinated response of the host immune system to bacterial infections is known to play a central role in the eradication of an infection. Therefore, the impact of antibiotics on both innate and acquired host immunity may be involved in the therapeutic outcome. The aim of this study was to evaluate the effects of the widely used cephalosporin cefaclor on some parameters of the immune system in ex vivo conditions. The results demonstrated that short-term (3 to 6 days) treatment with this antibiotic induced pleiotropic modification of rat spleen cells upon ex vivo stimulation with the polyclonal mitogen PHA, entailing increased lymphoproliferative responses, augmented IFN-gamma, IL-2 and IL-10 synthesis and decreased production of IL-4 and IL-6 in comparison to spleen cells from control rats. The mononuclear spleen cells of healthy rats released larger amounts of IFN-gamma and IL-2 in culture supernatants in response to polyclonal mitogenic stimulation with PHA compared to the spleens of the control rats receiving vehicle only. Simultaneously, the treatment with cefaclor augmented PHA-induced lymphoproliferative responses and reduced the synthesis of IL-4 and IL-6. These data depict a type 1 cytokine inducing and immunostimulatory pharmacological profile that, by activating the innate and acquired immune system, would be synergistic with cefaclor antibacterial activity.

[Management of acute pyelonephritis in patients older than 3 months: survey conducted in 39 paediatric emergency departments of the Ile de France Region in 2004]. / Prise en charge des pyélonéphrites aiguës du nourrisson de plus de 3 mois et de l'enfant: enquête effectuée parmi les services d'urgences pédiatriques d'Ile de France en 2004.

OBJECTIVES: To describe the different modalities of ambulatory management of acute pyelonephritis in patients older than 3 months of age in paediatric emergency units of the Ile de France region in 2004. METHODS: Between October 2003 and April 2004, referents of 39 paediatric emergency units of the Ile de France region were questioned through a written questionnaire concerning the management of acute pyelonephritis: in or outpatient modalities, antibiotic regimen (molecule and route of administration), investigations and follow-up. RESULTS: Thirty-one questionnaires (79.5%) were returned and analysed. A written protocol was available in 60% of the units. Outpatient management was performed in 24/31 centres. Young age, poor clinical tolerance, urological abnormalities and social difficulties were the major contra-indications for such management. Ultrasonic echography at diagnosis (within 24 h) was performed in 50% of the units. Antibiotics were started using IV route in 18/24 units (75%) and ceftriaxone and aminoside were respectively prescribed in 100% and 29.4% of the units for a duration of 1 to 5 days before switching to the oral route. Antibiotherapy was started orally in 6 units and cefixime was chosen by 5 of them. Follow-up consultations were scheduled in 100% of the units but with various delay after initiation of the treatment. The total duration of treatment was mostly 10 days and oral prophylactic antibiotherapy was prescribed by 10/24 centres after completion of the treatment. Cystoureterography was systematically realized by 83.3% of the units. CONCLUSIONS: Despite important differences in the management of acute pyelonephritis in Ile-de-France, a majority of the units follows similar therapeutic modalities. In the absence of consensus, new recommendations are necessary concerning the management of pyelonephritis in infants and children in France.

Do We Bury Antibacterials When Launching? Cefaclor Example.

This study aimed to compare existing dosing regimens of cefaclor with recommended pharmacokinetic/pharmacodynamic (PK/PD) parameters and to see if the proposed dosing regimen could have been the reason for development of bacterial resistance. PKs of cefaclor were determined after administrating the highest therapeutic dose of 750 mg in standard release (SF) and modified release form (MRF) in 12 volunteers. The study was performed on clinical isolates of the most frequent causative agents in urinary and respiratory infections. Minimum inhibitory concentration (MIC), postantibiotic effect, and PK/PD efficacy indices were determined. Peak plasma concentrations of 23.142 ± 5.67 (SF) and 8.7 ± 2.09 µg/mL (MRF) were observed after 40-60 min and 3.04 ± 0.75 h, respectively. MIC for investigated bacterial strains ranged from 1 to 4 mg/L. Postantibiotic effect lasted from 2.10-2.18 ± 0.2 h for Gram-positive to 0.58-0.90 ± 0.05 h for Gram-negative bacteria. PK/PD indices (t > MIC) ranged from 27.08 ± 5.93% to 43.23 ± 6.54% of 8-h dosing interval (SF) and 22.57 ± 8.93% to 49.65 ± 1.95% of 12-h dosing interval (MRF). Plasma levels were below MIC for more than 50% of the dosing interval even for the most sensitive pathogens (MIC = 1 mg/L). During both dosing intervals the total "antibacterial activity" was not longer than 6 h for Gram-positive and 5 h for Gram-negative bacteria for SF and 9 h for Gram-positive and 5 h for Gram-negative bacteria for MRF.

Effect of an educational intervention on oral cephalosporin use in primary care.

The prescribing of oral cephalosporin antibiotics in an ambulatory setting was evaluated before and after an educational intervention. A drug utilization review used previously developed criteria to study the indications, processes, complications, and outcome for oral cephalosporins in the outpatient setting. Baseline data were collected for one year in the initial phase of the study. Only one prescription (1.4%) in the initial phase (0.96% of the total) met the criteria for appropriate use. However, during the year after an educational intervention by a clinical pharmacist explaining the proper use of oral cephalosporins, the prescribing of these agents decreased substantially. Educational strategies in medical schools and residency programs that seek to improve drug-prescribing behavior should combine drug utilization review programs with specific education about the appropriate use of pharmacologic agents.

Blinded comparison of cefuroxime to cefaclor for lower respiratory tract infections.

Cefuroxime axetil was compared with cefaclor for the therapy for lower respiratory tract infections. Sixty-one patients were randomized to receive the following drug dosages: (1) cefuroxime axetil, 250 mg orally every 12 hours (21 patients); (2) cefuroxime axetil, 500 mg orally every 12 hours (21 patients); and (3) cefaclor, 500 mg orally every eight hours (19 patients). Of these 61 patients, 80% were male, with a mean age of 59.5 years; 56% had acute pneumonia, and the remainder had an acute bronchitis. Causative pathogens included typical respiratory tract pathogens. Overall, 23 of 27 patients with bronchitis were clinically cured at the end of therapy. Thirty-one of 34 pneumonias were clinically cured or improved at the end of therapy; the three pneumonia treatment failures occurred in the lower dose cefuroxime (n = 2) and cefaclor (n = 1) treatment groups. Overall, bacteriologic cure occurred in 86% of patients treated with 500 mg of cefuroxime axetil compared with 60% of cefaclor-treated patients. Adverse clinical effects were uncommon. From this study, it was concluded that cefuroxime given every 12 hours is at least as clinically efficacious as cefaclor; it is a new oral cephalosporin with pharmacologic and bacterial spectrum advantages over many older agents.

Antibacterial activity of glass-ionomer cement containing antibiotics on caries lesion microorganisms.

PURPOSE: To assess the total viable bacteria in infected dentin after sealing with glass-ionomer cement containing 1% metronidazole, 1% ciprofloxacin and 1% cefaclor. METHODS: 40 children were selected, with ages ranging from 4-10 years, with primary teeth with active carious lesions without any pulpal involvement. The patients were divided randomly into two groups in accordance to the glass-ionomer cement used to seal the carious lesions: Group 1 (control, n=20), sealing with conventional glass-ionomer cement; and Group 2 (test, n=20) sealing with glassionomer cement including antibiotics. The infected dentin was collected both before and 24 hours after the sealing of the cavities and, after inoculation in blood agar, all the plates were incubated in containers kept at 37 degrees C for 5 days in an atmosphere of 85% N2, 10% CO2 and 5% H2, for subsequent counting of total viable bacteria. RESULTS: The results were analyzed using the Wilcoxon and Mann-Whitney tests. The glass-ionomer cement with 1% of metronidazole, 1% of ciprofloxacin and 1% of cefaclor showed a significantly greater reduction in microbiota in the infected dentin in comparison to the reduction with the conventional ionomer cement (P< 0.01), with a mean reduction of 98.65% of all viable bacteria. The infected dentin after sealing with glass-ionomer cement with antibiotics showed, using scanning electron microscopy, the presence of bacterial aggregates, intertubular dentin with exposure of collagen fibers, and dentin tubules.

Efficacy of prophylaxis in women with sex induced cystitis.

UNLABELLED: Sexual intercourse has been established as one of the most important risk factors for both isolated and recurrent uncomplicated infections of the urinary tract. Prophylactic therapy requires only a small dose of an antimicrobial agent, which is generally given at bedtime for 6 to 12 months. An alternative method is to give an antimicrobial agent for six months post-intercourse. It is still unknown which of the two methods is most effective. A total of 123 women with suspected sexually induced recurrent cystitis (mean age 28 years, range 15 to 65) and a history of recurrent urinary tract infection (UTI) (the last one within the last six months) were subjected to prophylactic therapy for six months. Half of them were treated with low-dose trimethoprim-cotrimoxazole (TMP-SMX) and cefaclor given orally post-intercourse (spontaneous usage), while the other half were treated with low-dose TMP-SMX and cefaclor given at bedtime. The response to the prophylactic therapy was classified as continued cure in 106 cases (86.17%), failure in 13 cases (10.56%), and unknown in four cases (3.25%). TMP-SMX administered in continuous nightly prophylaxis showed similar efficacy and tolerability as cefaclor post-intercourse. OBJECTIVE: To determine the efficacy of prophylaxis in women with recurrent sex induced cystitis and compare the post-intercourse versus the conventional bedtime given long-term, low-dose use of prophylactic antimicrobials.

Single-dose cefaclor therapy of urinary tract infection. Evaluation of antibody-coated bacteria test and C-reactive protein assay as predictors of cure.

The efficacy of single-dose (cefaclor, 2 g orally) and multidose (cefaclor, 250 mg orally three times a day for 10 days) antibiotic regimens in the therapy of acute uncomplicated urinary tract infections (UTI) in nonpregnant women were compared. The patient's clinical status and results of urine cultures were compared in retrospect with the results of the antibody-coated bacteria (ACB) test and C-reactive protein (CRP) test in order to determine if either test would predict the patient's response. Overall, 10 of 30 patients (33 percent) and 18 of 22 patients (81 percent) given single doses and multidoses, respectively, had negative urine cultures four weeks after completion of therapy. A negative urine culture at four weeks correlated with a negative ACB test utilizing the less inclusive criteria for negativity (less than 5 bacteria with fluorescence in 5 minutes of search) but not with a negative ACB test utilizing the more inclusive criteria (less than 10 percent bacteria with fluorescence) or with a negative CRP test. The cure rate in the ACB-negative single-dose group (7 of 9 patients) utilizing the less inclusive criteria for negativity was similar to the cure rate in the ACB-negative multidose group (8 of 10 patients). This study suggests that the ACB test, if properly standardized, might permit identification of a population of patients with UTI who would respond to single-dose cefaclor therapy.