Risk factors and molecular analysis of panton-valentine leukocidin-positive methicillin-resistant Staphylococcus aureus colonization in healthy children.

BACKGROUND: Nasal carriage of Panton-Valentine leukocidin (PVL)-positive methicillin-resistant Staphylococcus aureus (MRSA) is associated with community associated disease. The risk factors for and characteristics of PVL-positive MRSA colonization in the healthy pediatric population are not well understood. METHODS: Anterior nares cultures were obtained from healthy children < or =14 years of age presenting for health maintenance visits or attending 1 of 8 kindergartens during a 3-year period. A case-control study and molecular typing studies were performed. RESULTS: A total of 131 (8.1%) of 1615 children had nares cultures positive for MRSA, and 25 (1.5%) were colonized with PVL-positive MRSA. Nasal colonization of PVL-positive MRSA was significantly higher in 2006 than in 2004 (2.8% versus 0.7%; P = 0.006). By multivariate analysis, antibiotic use during the past 12 months (odds ratio, 29.37; 95% confidence interval, 10.72-80.50; P < 0.001) was the major risk factor associated with PVL-positive MRSA colonization in healthy children. Comparison of hospital MRSA strains with the community colonization strains by antimicrobial susceptibility testing, macrolide-lincosamide-streptogramin resistance gene testing, staphylococcal cassette chromosome mec typing, exotoxin profiling, and pulsed-field gel electrophoresis typing revealed that clonal spread of PVL-positive MRSA distinct from clinical hospital strains contributed to the high PVL-positive MRSA burden in the community. CONCLUSIONS: Nasal PVL-positive MRSA colonization in healthy children with no relationship to the hospital setting has increased significantly in the past 3 years, suggesting that it may be a major factor in the emergence of community-acquired MRSA disease in Taiwan. Previous antibiotic use was associated with PVL-positive MRSA colonization.

Low rate of nasopharyngeal carriage and high rate of ampicillin resistance for Haemophilus influenzae among healthy children younger than 5 years old in northern Taiwan.

BACKGROUND AND PURPOSE: Surveillance data of colonization by Haemophilus influenzae in Taiwan are lacking. This study aimed to define the nasopharyngeal carriage rate of H. influenzae among children younger than 5 years in northern Taiwan, and to determine the antibiotic susceptibility, serotype and the clonal relationship of these isolates. METHODS: Nasopharyngeal specimens were obtained from 511 healthy children younger than 5 years. All H. influenzae isolates were serotyped. The minimal inhibitory concentrations for various antibiotics were determined. Pulsed-field gel electrophoresis (PFGE) was used for clonal analysis. RESULTS: Among 511 children, 269 (52.6%) had been vaccinated with at least one dose of H. influenzae type b (Hib) conjugate vaccine, 236 (46.2%) were unvaccinated and 6 (1.2%) had no vaccination records available. Twenty six H. influenzae strains were isolated. There were three Hib isolates and the others were nontypeable H. influenzae (NTHi). The carriage rate for Hib was 0.6% (3/511) and of NTHi was 5% (23/511). Three (1.27%) of the 236 unvaccinated children were carriers of Hib, whereas none of the 269 vaccinated children carried Hib. Two out of the three Hib isolates and 14 (60.9%) of 23 NTHi isolates were ampicillin-resistant. Multidrug resistance was found in 7 (26.9%) of the isolates. Among the isolates, 61.5% were beta-lactamase producers; there were no beta-lactamase-negative ampicillin-resistant isolates. The PFGE restriction patterns showed a wide diversity of genotypes. CONCLUSIONS: There is very low nasopharyngeal carriage of Hib among children younger than 5 years in northern Taiwan. This may explain why the incidence of invasive Hib disease is also low in Taiwan. In addition, we found a high prevalence of beta-lactamase-positive ampicillin-resistant nasopharyngeal H. influenzae isolates.

Changing trend in antimicrobial resistance of pediatric uropathogens in Taiwan.

BACKGROUND: There is growing concern regarding antimicrobial resistance worldwide, particularly of Escherichia coli, and the first choice of an antimicrobial agent for empiric treatment of pediatric urinary tract infection (UTI) is not well established. METHODS: The medical records from January 1991 to December 2005 for all children under 18 years of age admitted to Tri-Service General Hospital, Taipei for their first UTI were reviewed. Two study periods, early (1991-2000) and late (2001-2005), were chosen during the 15 year period for evaluating the trend of antimicrobial resistance. RESULTS: Of the 368 isolates, E. coli was the most common pathogen (81.0%), followed by Klebsiella pneumoniae (6.5%), Enterococcus spp. (6.0%), and Proteus mirabilis (3.5%). Of the 368 isolates, 77.4% were resistant to ampicillin, 44.6% to co-trimoxazole, 27.2% to cephalothin, 15.0% to gentamicin, and 8.4% to nitrofurantoin. In the early (1991-2000) and late (2001-2005) study periods, 199 isolates (54.1%) and 169 isolates (45.9%), respectively, were compared. The resistance to antimicrobial agents for overall pathogens in the early and late study periods, respectively, was as follows: 68.8% and 88.0% to ampicillin, 48.9% and 46.6% to co-trimoxazole, 26.8% and 28.9% to cephalothin, 16.2% and 19.8% to gentamicin, and 8.7% and 9.0% to nitrofurantoin. CONCLUSION: Among commonly used antimicrobial agents for the treatment of pediatric UTI, there is a trend towards increasing resistance to ampicillin and a persistently low resistance rate to gentamicin, cephalosporin, and nitrofurantoin. Parenteral first-generation cephalosporins, gentamicin, and oral nitrofurantoin should be considered for first-line agents, given the resistance patterns of this study.

Does a normal DMSA obviate the performance of voiding cystourethrography in evaluation of young children after their first urinary tract infection?

OBJECTIVE: To determine whether a normal technetium-99m-labeled dimercaptosuccinic acid (DMSA) renal scan obviates the need for voiding cystourethrography (VCUG) in evaluating young children after their first urinary tract infection (UTI). STUDY DESIGN: This was a 10-year retrospective review of 142 children (age < or = 2 years, 77 boys and 65 girls) who had their first UTI and were admitted to a tertiary care general hospital. The association between DMSA renal scan results and VCUG results performed 48 hours and 1 month after diagnosis was evaluated. RESULTS: DMSA renal scans and VCUG were performed in 142 patients. Of these, 99 patients (69.7%) had evidence of pyelonephritis, although only 2 (1.4%) had evidence of renal scarring; 42 (29.6%) had vesicoureteral reflux (VUR) on VCUG. The sensitivity, specificity, positive and negative predictive values, and likelihood ratio negative for abnormalities on DMSA renal scans for detecting the the presence of VUR on VCUG were 88% (95% confidence interval [CI] = 73% to 100%), 36% (95% CI = 26% to 46%), 37% (95% CI = 27% to 46%), 88 % (95% CI = 73% to 100%), and 0.33 (95% CI = 0 to 0.88), respectively. CONCLUSIONS: Children with a negative DMSA renal scan during their first UTI episode rarely have VUR and may never have high-grade VUR. Avoiding VCUGs in children with negative DMSA renal scans could significantly reduce the use of this potentially traumatic test.

Nasal carriage of a single clone of community-acquired methicillin-resistant Staphylococcus aureus among kindergarten attendees in northern Taiwan.

BACKGROUND: To evaluate the prevalence and microbiological characterization of community-acquired (CA) methicillin-resistant Staphylococcus aureus (MRSA) nasal carriage in a kindergarten. METHODS: Point prevalence study. Nasal swabs were collected from healthy children younger than 7 years of age who were attending a kindergarten in Taipei, Taiwan. A parent questionnaire regarding MRSA risk factors was administered simultaneously. All CA-MRSA colonization isolates were archived for subsequent antimicrobial susceptibility and molecular typing. RESULTS: Of the 68 children who participated in the study, 17 (25%) had S. aureus isolated from nasal swabs. Nine (13.2%) of the 68 children had CA-MRSA carriage, and none of them had any identified risk factors. Antimicrobial susceptibility testing revealed all of the 9 CA-MRSA colonization isolates had uniformly high resistance (100%) to both clindamycin and erythromycin, the macrolide-lincosamide-streptogramin-constitutive phenotype and the ermB gene. Pulsed-field gel electrophoresis revealed 8 (88.9%) of 9 CA-MRSA colonization isolates were genetically related and multilocus sequence typing revealed all isolates had sequence type 59. All of the colonization isolates carried the staphylococcal cassette chromosome mec type IV, but none were positive for the Panton-Valentine leukocidin genes. CONCLUSION: The results of this study suggest that a single predominant CA-MRSA colonization strain featuring high clindamycin resistance circulated in this kindergarten. Additionally, due to the established transmissibility of colonization isolates, the high prevalence of nasal carriage of CA-MRSA among healthy attendees in kindergartens may indicate the accelerated spread of CA-MRSA in the community.

Kinetics of adaptive immunity to Haemophilus influenzae type b meningitis in transgenic mice: evidence from diverse expression of double T1/T2 transgenes and Th1/Th2-related cytokines.

To investigate the kinetic changes in adaptive immunity during experimental Haemophilus influenzae type b (Hib) meningitis, we established a murine meningitis model based on T1/T2 doubly transgenic mice. These mice carry two transgenes that express two distinct cell-surface markers: a human Thy1 transgene (hThy1) under the control of the murine IFN-gamma promoter, and a murine Thy1.1 transgene (mThy1.1) under the control of the murine IL-4 promoter, designated T1 and T2, respectively. Mice infected with Hib displayed severest symptoms and lowest total splenocyte counts on day 3 after infection. Simultaneously, we examined the significantly low percentage of CD19+ B cells, the relatively high level of CD4+ T cells and significantly high percentage of CD8+ T cells in Hib-infected mice. Furthermore, we observed the early induction of both Th1 and Th2 responses, in terms of the augmentation of Th1 cells (IFN-gamma-producing CD4+ T cells) and Th2 cells (IL-4-producing CD4+ T cells) in Hib-infected mice. On day 7 after infection, the Th1 response gradually declined and the Th2 response rather sustained. Two weeks after infection, both Th1 and Th2 cells were barely detectable. Moreover, we demonstrated using an antigen-specific re-stimulation test to analyze the effector function of lymphocyte subsets that CD8+ T cells contributed to more predominantly production of IFN-gamma than CD4+ T cells did; and CD4+ T cells partly contributed to the secretion of IL-4 from flowcytometry of intracellular cytokine staining. Our results support that these transgenic mice provide an available model to dissect the complex kinetic change of adaptive immunity in bacterial infectious diseases.

Antimicrobial resistance patterns and serotype distribution of invasive Streptococcus pneumoniae isolates from children in Taiwan from 1999 to 2004.

Streptococcus pneumoniae causes substantial morbidity and mortality worldwide. Because only limited data are available for the antibiotic resistance patterns and seroepidemiology of invasive S. pneumoniae isolates in Taiwanese children, this national surveillance of invasive pneumococcal infections in children was conducted during a 5-year period. Invasive isolates of S. pneumoniae were obtained from sterile sites (yielding blood and cerebrospinal, pleural, and intra-articular fluids) in children (aged < or =14 years) at a total of 40 regional hospitals and medical centers distributed throughout Taiwan. The collection period was between July 1999 and June 2004, with a total of 286 isolates (including 30 cerebrospinal fluids) collected. All the samples were sent to the Center for Disease Control in Taipei for serotyping and susceptibility testing. Of the 286 S. pneumoniae isolates studied, the 5 most common serotypes were 14 (28.3%), 23F (21.0%), 6B (17.1%), 19F (13.6%), and 3 (4.9%). Intermediate- and high-level penicillin resistance was determined for 50.7% and 25.5% of the isolates, respectively. Isolate resistance was demonstrated to erythromycin (93%), tetracycline (82.2%), trimethoprim/sulfamethoxazole (79.4%), cefotaxime (11.2%), and levofloxacin (0.3%). Multiple drug resistance was found for each serotype, but mostly in types 14, 23F, 6B, and 19F. Overall, 85.0% of the serotypes, 90.8% of the penicillin-nonsusceptible S. pneumoniae (PNSSP), and 90.1% of the multiple drug-resistant (MDR) isolates were covered by the heptavalent pneumococcal conjugated vaccine (PCV7). In this study, we found a diverse pulse-field gel electrophoresis pattern among MDR isolates: a high prevalence of drug resistance and a continued increasing trend in penicillin resistance among nationwide pneumococcal isolates from children in Taiwan. The highest prevalence of invasive pneumococcal disease was in children aged 2 to 5 years, and the highest PNSSP prevalence and highest PCV7 coverage were in children aged <2 years. In terms of reducing the risk of invasive pneumococcal illness in Taiwan, the use of PCV7 is likely to have a beneficial effect similar to that obtained in countries that have used it.

Bacteriology and antibiotic susceptibility of community-acquired intra-abdominal infection in children.

BACKGROUND AND PURPOSE: Intra-abdominal infection can be a life-threatening condition in children, and aggressive treatment is usually needed. The treatment should include surgical correction and drainage, and administration of antimicrobials that are effective against both aerobic and anaerobic microorganisms. This study investigated the microbiological characteristics of intra-abdominal infection of children in Taiwan. METHODS: Data for bacterial specimens from 113 children (64 males), aged from 9 months to 18 years, who had community-acquired intra-abdominal infections at our hospital during a 10-year period were analyzed. RESULTS: In total, 113 specimens were collected, including those with only aerobes (62%), and those with mixed aerobic and anaerobic species (35%). A total of 239 aerobes and 86 anaerobes were isolated. Polymicrobial infection was found in 79% of specimens. The predominant aerobe was Escherichia coli (42%), and Bacteroides fragilis (36%) was the most frequently isolated anaerobic microorganism. Enterococcus was detected in about 14% of Gram-positive aerobic isolates. Review of the results of antibiotic susceptibility testing revealed that the Gram-positive aerobes, apart from staphylococci, had a high susceptibility rate to ampicillin, and 84% of Gram-negative aerobes were susceptible to gentamicin. In addition, B. fragilis showed a high resistance rate to clindamycin (52%) but all of these isolates were susceptible to metronidazole. CONCLUSION: Triple antibiotic combination therapy including ampicillin, gentamicin and metronidazole remains an alternative empirical antibiotic therapy for pediatric patients with mild to moderate community-acquired intra-abdominal infection.

Safety monitoring in vaccine development and immunization.

The development of vaccines has been one of the most important achievement in preventive medicine. As the incidence of vaccine-preventable diseases is reduced by immunization, general public becomes increasingly concerned about the safety associated with vaccine. Vaccine safety is extensively evaluated through animal safety studies, clinical trials, during manufacturing processes, and postlicensure surveillance. Safety monitoring in postlicensure surveillance has relied on passive reporting system and epidemiological studies, including Vaccine Adverse Event Reporting System (VARES), Vaccine Safety Datalink (VSD) Project and others. Approximately 10,000 reports per year are submitted to VAERS. About 15% of these describe serious events and 85% of reports are classified as not-serious events. The system analyzed frequently reported adverse reactions, rare events, intussusception after rotavirus vaccine, cases of sudden infant death syndrome (SIDS), and safety of various vaccines. The evidence for a causal relationship with vaccines can be classified into five categories: no evidence, evidence was inadequate to accept or reject, evidence favors rejection, evidence favors a causal relationship, and evidence established. Future challenges involve improving survey and monitoring system of adverse events after immunization, enhancing vaccine safety research and vaccine risk communication, and possibility of increased reactogenicity in new and combined vaccines.

Dizygotic twins discordant for early-onset Citrobacter koseri and group B streptococcal sepsis.

Early-onset neonatal sepsis is usually a multisystem fulminant illness with prominent respiratory symptoms, and typically the infant has acquired the organism from the maternal genital tract during the intrapartum period. In this article, we report a rare case of dizygotic twins where each individual suffered early-onset sepsis caused by a different pathogen. Group B streptococcal (GBS) sepsis was diagnosed in twin A 1 day after birth; sepsis and meningitis caused by Citrobacter koseri was diagnosed in twin B at the age of the 4 days. The mother developed pre-eclampsia and fever and the twins were delivered via cesarean section at 35 week's gestation. Twin A received ampicillin treatment for 14 days and recovered fully. Twin B was treated with ceftriaxone for 4 weeks and follow-up brain ultrasound revealed persistent enlargement of the bilateral-lateral ventricles. When empiric antibiotic is considered for the symptomatic twin of a sibling with early-onset GBS infection, samples of blood and cerebrospinal fluid (CSF) should be obtained for culture study before treatment. Adjustment of antibiotic treatment based on the results of cultures and CSF Gram stain and antibiotic susceptibility test is essential.

Epidemiological typing of community-acquired methicillin-resistant Staphylococcus aureus isolates from children in Taiwan.

BACKGROUND: A 1400-bed tertiary medical center in northern Taiwan was used to conduct an epidemiological study of children hospitalized with community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infection during a 5-year period. METHODS: Nineteen previously healthy children with predominantly skin and soft-tissue CA-MRSA infections were enrolled into the study. Seventeen CA-MRSA isolates were examined for antimicrobial susceptibility and molecular typing. RESULTS: A comparison of our results with the reported resistance rates among CA-MRSA isolates from other countries showed uniformly high macrolide resistance (100%). Of the 17 MRSA isolates in our study, all had the macrolide-lincosamide-streptogramin-constitutive phenotype and the ermB gene. Moreover, on the basis of molecular typing results, 11 (65%) of 17 CA-MRSA isolates were genetically related (as determined by pulsed-field gel electrophoresis), and multilocus sequence typing revealed a sequence type of 59 in all isolates. Staphylococcal toxin genes lukS-PV and lukF-PV were detected in all isolates. However, staphylococcal cassette chromosome mec type IV was only detected in 3 (17.6%) of 17 isolates; the remaining 14 isolates were untypeable. CONCLUSIONS: Analysis of our data suggests the predominance of a single endemic CA-MRSA strain with high macrolide resistance in our community. Clinical improvement with incision and drainage was noted for most patients, despite treatment with an ineffective antibiotic, so the need for a change in treatment guidelines should be addressed.

Enterotoxin B is the predominant toxin involved in staphylococcal scarlet fever in Taiwan.

This study retrospectively reviewed all pediatric cases of staphylococcal scarlet fever (SSF) that occurred during a 10-year period in a 1400-bed tertiary medical center in northern Taiwan. All 20 cases of SSF occurred in previously healthy individuals. Skin and soft-tissue infections predominated among children from whom Staphylococcus aureus was isolated. Polymerase chain reaction testing was used to detect known staphylococcal toxin genes, and of the isolates studied, most (18 [90%] of 20) contained only the staphylococcal enterotoxin B. One of the other strains was positive for staphylococcal enterotoxin A only, and the last strain was positive for both staphylococcal enterotoxin G and staphylococcal enterotoxin I. Pulsed-field gel electrophoresis identified a small cluster of isolates (6 [30%] of 20) that were genetically related, but these strains came from epidemiologically unrelated patients during a 3-year period.

A nursery outbreak of Staphylococcus aureus pyoderma originating from a nurse with paronychia.

An outbreak of methicillin-susceptible Staphylococcus aureus pyoderma occurred in the nursery of a tertiary-care referral center. All strains retrieved from the outbreak, including one from a nurse's infected finger, were typed by arbitrarily primed polymerase chain reaction and automated ribotyping. The results indicated that the spread of the outbreak was probably facilitated by contamination of the nurse with paronychia.

Epidemiology of invasive pneumococcal infection in Taiwan: antibiotic resistance, serogroup distribution, and ribotypes analyses.

From July, 1998, to June, 1999, pneumococcal isolates from 288 patients with invasive disease in Taiwan were serogrouped and tested for their susceptibility to various antibiotics. Automated ribotyping was used to study their molecular epidemiology. The mortality rate among those > or = 65 years was higher than those 18 or 19-64 years (p < 0.001). The total incidence of infection was significantly higher during the cooler season than the warmer season (p = 0.017). Among strains isolated from children aged < or = 18 years, 76% were not susceptible to penicillin, a rate that was significantly higher (p < 0.001) than that for adults (45%), as was the susceptibility to azithromycin, erythromycin, and trimethoprim-sulfamethoxazole (p < 0.005). The most prevalent serogroup encountered in the invasive isolates was 23, followed by 6, 14, 19, and 3. Isolation of Streptococcus pneumoniae in cerebrospinal fluid was at high rate in children under 5 years (p = 0.00012). Molecular typing revealed a high degree of polymorphism among the isolates. Among serogroup 23 and 19 isolates, a high proportion had the same ribotypes, the Taiwan23F-15 and Taiwan19F-14 isolates, suggesting the circulation of a Taiwanese epidemic strain. In Taiwan, S. pneumoniae isolates should be tested for their resistance profile for children < or = 18 years old, as these are more likely to harbor high-level resistance. Control of pneumococcal infection with the 7-valent-conjugated vaccine should also be considered because it is estimated that it would cover nearly 90% of the serotypes among pediatric invasive disease.

Use of automated riboprinter and pulsed-field gel electrophoresis for epidemiological studies of invasive Haemophilus influenzae in Taiwan.

A total of 87 invasive isolates of Haemophilus influenzae isolated throughout Taiwan from 1994 to 1998 was collected; 57 were from children <14 years old. In all, 60.9% of isolates were resistant to ampicillin and produced beta-lactamase. Ribotyping revealed six different profiles in 55 isolates of type b, nine profiles in 10 isolates of non-type b and 12 profiles in 22 isolates of non-typable H. influenzae. Among isolates from 35 cases of meningitis, 30 (86%) were in ribogroups 1, 2 and 3 with >90% genetic similarity. Compared with all the other ribogroups, ribogroups 1, 2 and 3, which encompassed all H. influenzae type b, were significantly more prevalent as a cause of meningitis in children <14 years old. Further subtyping of the predominant ribogroup by pulsed-field gel electrophoresis (PFGE) identified differences of 0-6 bands among these isolates of ribogroup 1, which indicated distant relatedness. Automated ribotyping was found to be a useful method and was less time-consuming for molecular epidemiology studies of H. influenzae. PFGE is suggested as an addition to ribotyping to improve discrimination if H. influenzae type b is involved. Differentiating ribogroups between type b and non-type b H. influenzae by genotyping may help to understand the molecular characteristics of outbreaks, endemicity and value of vaccination. According to the results of ribotyping and PFGE, it seems possible that spread of invasive H. influenzae type b had occurred and ribotyping confirmed that there was no clonal spread of non-type b H. influenzae in Taiwan.

Rate of nasopharyngeal carriage, antimicrobial resistance and serotype of Streptococcus pneumoniae among children in northern Taiwan.

Multiple-antibiotic-resistant strains of Streptococcus pneumoniae are isolated from clinical specimens in Taiwan with increasing frequency. This study aimed to define the carriage rate of S. pneumoniae among children in northern Taiwan, and to determine the antibiotic susceptibility and the serotype incidence of these isolates. Nasopharyngeal swabs were taken from a total of 478 children (age, 1 month-14 years) who sought medical care only for non-infectious disease or routine vaccination at our hospital between July 1998 and November 1999. S. pneumoniae was isolated from 95 patients, and the collected isolates were available for analysis. All pneumococcal isolates were serotyped and their antimicrobial susceptibility tested by standard methods. The total rate of pneumococcal carriage in the study population was 19.9% and the isolation rate was higher in children aged between 2 and 5 years. Only 10 (10.5%) of the isolates were susceptible to penicillin (minimum inhibitory concentration [MIC], < or = 0.06 microg/mL); 47 (49.5%) isolates were intermediately resistant (MIC, 0.12-1 microg/mL) and 38 (40%) were highly resistant (MIC, > or = 2 microg/mL). Among the 95 S. pneumoniae isolates, the common serotypes were 23F (22%), 6B (18.9%), 19F (18.9%), and 14 (8.4%). Evaluation of the results showed that serotypes 23F (24.7%), 19F (21.2%), 6B (15.3%), and 14 (9.4%) composed 70.6% of all penicillin-non-susceptible S. pneumoniae isolates. The significant rate of isolation of penicillin-non-susceptible S. pneumoniae from children indicates that both the judicious use of antibiotics and the availability of conjugate pneumococcal vaccines are the most appropriate strategy to reduce the carriage of resistant pneumococci.

Clinical characteristics of Staphylococcal pyomyositis.

Pyomyositis is common in the tropics but rarely reported in temperate climates. This disease may give rise to obscure, non-specific, or misleading signs and symptoms. Delayed diagnosis and treatment may lead to death. The most common pathogen is Staphylococcus aureus. We analyzed 8 cases treated in the Tri-Service General Hospital between 1989 and 2001. There were 3 males and 5 females with age ranging from 2 to 66 years. Fever was found in all patients. The mean time lag between the onset of minor symptoms and diagnosis was 10 days. The imaging tools used included sonography, gallium-67 scan, computed tomography, and magnetic resonance imaging. Early application of sonography to any suspected lesions can help to establish diagnosis. All 8 patients recovered smoothly without complications after incision, drainage, and administration of adequate antibiotics for 2 to 4 weeks.

Cat-scratch disease in children at a medical center.

BACKGROUND: Cat-scratch disease (CSD) is a well-recognized, benign, self-limited regional lymphadenopathy occurring in immunocompetent patients. Several retrospective studies have demonstrated that CSD occurs at all ages, however, the disease appears to be more common in children. We conducted a retrospective case study of CSD in children presenting at our hospital, and reviewed the relevant literature. METHODS: The medical records for eight children (age range 4-13 years) diagnosed with cat-scratch disease at the Tri-service General Hospital in Taipei from September 1, 1986 to September 1, 2002 were retrospectively reviewed. Clinical manifestations, diagnostic methods, and treatment types were assessed. RESULTS: The male gender predominated (75%); the median age was 8.6 years. The latency period ranged from 7 days to 1 month, with a median diagnostic interval of 8.5 days. There were no deaths. All patients had lymphadenopathy, and the axillary node was the most prevalent site (62.5%). The most common locations for the scratch or inoculation lesions were the hands and/or fingers (62.5%). Three patients were diagnosed from clinical symptoms and history (37.5%), three from serological study (37.5 %), and two using biopsy or aspiration (25%). All patients were given antibiotic treatment. The most commonly used antibiotic was gentamicin (75%), with the average duration of treatment 8.7 days. The average hospital stay was 8 days, with the lymph-node size reduced relative to pretreatment baseline in all except one case. CONCLUSION: In our experience, the long-term prognosis for children with typical CSD is favorable, and gentamicin may be a good antibiotic option.

The role of antimicrobial therapy for treatment of uncomplicated skin and soft tissue infections from community-acquired methicillin-resistant Staphylococcus aureus in children.

BACKGROUND AND PURPOSE: Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infections in skin and soft tissues are increasing in children in Taiwan. This study investigated the outcomes of therapy with or without appropriate antibiotics among children with CA-MRSA skin and soft tissue infections (SSTIs), and analyzed the outcomes of management among children with Panton-Valentine leukocidin (PVL)-positive strains and PVL-negative strains. METHODS: In this retrospective study, data for CA-MRSA SSTIs from 107 children younger than 18 years were analyzed. Worsening infection or other surgical therapy were considered treatment failure. Antimicrobial therapy was considered appropriate if it included at least 1 agent to which the organisms showed in vitro susceptibility. RESULTS: The rate of successful treatment was 90.7% (97 episodes). Eighty six children (80.4%) underwent incision and drainage as part of their initial therapy. Four of 5 children (80%) treated with an appropriate antibiotic initially were treated successfully, compared with 93 of 102 children (91.2%) who did not receive an appropriate antibiotic agent (p = 0.394; Fisher's exact test). Treatment failed for 5 of the 39 patients (12.8%) with PVL-positive SSTI CA-MRSA compared with only 1 treatment failure among 11 patients (9.1%) with PVL-negative SSTI CA-MRSA (p = 1.0; Fisher's exact test). CONCLUSIONS: The high rate of successful treatment among children with uncomplicated CA-MRSA SSTIs, even when given inappropriate antibiotic therapy, suggests that treatment of these uncomplicated infections without appropriate antibiotic therapy is possible. Incision and drainage may play an important role in the treatment of uncomplicated SSTIs.

Methicillin-resistant Staphylococcus aureus in children, Taiwan.

Highly virulent community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) with Panton-Valentine leukocidin (PVL) is common worldwide. Using antimicrobial drug susceptibility testing, staphylococcal cassette chromosome mec typing, exotoxin profiling, and pulsed-field gel electrophoresis typing, we provide evidence that supports the relationship between nasal strains of PVL-positive MRSA and community-acquired disease.