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Christine C Chiou

Publications and source records attributed to Christine C Chiou.

14 recordsLinked to original sources

Serotype and antimicrobial resistance patterns of Streptococcus pneumoniae isolated from Taiwanese children: comparison of nasopharyngeal and clinical isolates.

This report describes the serotypes and antimicrobial resistance patterns of 860 strains of Streptococcus pneumoniae isolated from nasopharyngeal (NP) carriers and clinical specimens collected from Taiwanese children during the years 1997 to 2003. The 6 most common serotypes/groups were 23F, 19F, 6B, 14, 6A, and 3. These accounted for 652/716 (91.1%) of the NP and 131/144 (91.0%) of the clinical isolates. Serotype 23F was the most common isolate in the NP carriers (25.7%, 184/716). Serogroup14 was most common in the clinical isolates (29.2%, 42/144) and the most frequent invasive isolate (43.4%, 33/76). It was more frequently associated with invasive infection than all other serotypes/groups (odds ratio = 7.2; 95% confidence interval, 4.16-12.46; P < .0001). Resistance to macrolides was high in all serotypes/groups, which ranged from 70% to 97%. Resistance to penicillin varied among the 6 leading serotypes/groups, ranging from 3% in serogroup 3 to 99% in serotype 19F. Serotype 23F was most likely to be multidrug resistant to penicillin, macrolides, and chloramphenicol compared with all others (107/150 [71%] versus 105/461 [23%], P < .0001). The potential coverage by the pentavalent and heptavalent vaccines was 83% for all isolates, but was significantly lower for NP than clinical isolates (81% versus 92%, P< .01). These findings provide baseline data to compare trends in the distribution of pneumococcal serotypes and antibiotic resistance patterns with the introduction of childhood pneumococcal vaccination in Taiwan and other countries.

Adolescent↗

Problem pathogens: paediatric legionellosis--implications for improved diagnosis.

Legionnaires' disease is an established and frequent cause of pneumonia in adults but is thought to be a rare cause in children. We reviewed the medical literature for cases of Legionnaires' disease in children and analysed the epidemiology, clinical characteristics, and treatment. 76 cases of legionella infection in children were identified. In 56%, diagnosis was made with culture methodology. 46% were community-acquired infections. 51.5% were under 2 years of age. 78% of the patients had an underlying condition such as malignancy. Fever, cough, and tachypnoea were the most common symptoms. The overall mortality rate was 33% and was higher in immunosuppressed children and in children younger than the age of 1 year. Patients who were treated empirically with anti-legionella therapy had a notably lower mortality rate compared with patients on inappropriate therapy (23%vs 70%). In 88% of hospital-acquired cases, an environmental link to potable water colonised with legionella was identified. We found no clinical features unique to Legionnaires' disease in children that would allow differentiation from pneumonia due to other respiratory pathogens. Awareness of legionella as a potential cause of paediatric pneumonia is particularly important because infection can be severe and life threatening and antimicrobial therapy often used for empirical therapy in children is not effective against legionella. In any case of pneumonia unresponsive to antibiotics, Legionnaires' disease should be considered and specific diagnostic tests to verify this diagnosis should be done. As legionella diagnostic tests become more widely applied, we predict that legionellosis may appear as an emerging infectious disease in children.

Adolescent↗

Concomitant Candida epiglottitis and disseminated Varicella zoster virus infection associated with acute lymphoblastic leukemia.

Acute epiglottitis by nonbacterial pathogens is an uncommon but life-threatening clinical entity. Herein, we report the concomitant occurrence of Candida epiglottitis and mucosal and visceral Varicella zoster virus infection in a child with acute lymphoblastic leukemia. Both infections were atypical in their presentation, occurred in a severely immunocompromised host, and required invasive procedures for diagnosis.

Candidiasis↗

High carriage rate of high-level penicillin-resistant Streptococcus pneumoniae in a Taiwan kindergarten associated with a case of pneumococcal meningitis.

BACKGROUND: The Taiwan19F-14 Streptococcus pneumoniae clone and its variants are being found with increasing frequency in the Asia-Pacific region. A 5-year old child with S. pneumoniae meningitis caused by a high-level penicillin resistant strain (MIC = 4 microg/ml) was admitted to a hospital in southern Taiwan. We carried out a study to determine the potential source of this strain. METHODS: Nasopharyngeal cultures were obtained from all children attending the same kindergarten as the index case. To determine their relatedness all isolates were compared by serotype, antimicrobial susceptibility profile and pulsed field gel electrophoresis (PFGE). RESULTS: A high proportion of the children including the index case (32/78, 41.0%) carried S. pneumoniae in their nasopharynx (NP). The most common serotype was 19F (13/32, 40.6%). The PFGE types of the 19F serotype isolates obtained from the patient's blood, CSF and NP were identical and were related to 11 other serotype 19F NP isolates including 10 that were indistinguishable from the Taiwan19F-14 clone. All 14 isolates had similar high-level penicillin and multi-drug resistance. The serotypes of the other 19 NP isolates included 6A (2), 6B (10), 23F (5), 9V (1) and 3 (1). The overall rate of penicillin resistance in these S. pneumoniae from these children was 87.5% (28/32), with an MIC50 of 2 and MIC90 of 4 ug/ml. In addition, multi-drug resistant-isolates (isolates resistant to 3 different classes of antimicrobials) accounted for 87.5% (28/32) of all isolates. CONCLUSION: The high carriage rate of high-level penicillin- and multi-drug- resistant S. pneumoniae in a kindergarten associated with a case of pneumococcal meningitis emphasizes the need for restraint in antibiotic use and consideration of childhood immunization with conjugate pneumococcal vaccine to prevent the further spread of resistant S. pneumoniae in Taiwan.

Carrier State↗

Epidemiology and outcome of zygomycosis: a review of 929 reported cases.

BACKGROUND: Zygomycosis is an increasingly emerging life-threatening infection. There is no single comprehensive literature review that describes the epidemiology and outcome of this disease. METHODS: We reviewed reports of zygomycosis in the English-language literature since 1885 and analyzed 929 eligible cases. We included in the database only those cases for which the underlying condition, the pattern of infection, the surgical and antifungal treatments, and survival were described. RESULTS: The mean age of patients was 38.8 years; 65% were male. The prevalence and overall mortality were 36% and 44%, respectively, for diabetes; 19% and 35%, respectively, for no underlying condition; and 17% and 66%, respectively, for malignancy. The most common types of infection were sinus (39%), pulmonary (24%), and cutaneous (19%). Dissemination developed in 23% of cases. Mortality varied with the site of infection: 96% of patients with disseminated disease died, 85% with gastrointestinal infection died, and 76% with pulmonary infection died. The majority of patients with malignancy (92 [60%] of 154) had pulmonary disease, whereas the majority of patients with diabetes (222 [66%] of 337) had sinus disease. Rhinocerebral disease was seen more frequently in patients with diabetes (145 [33%] of 337), compared with patients with malignancy (6 [4%] of 154). Hematogenous dissemination to skin was rare; however, 78 (44%) of 176 cutaneous infections were complicated by deep extension or dissemination. Survival was 3% (8 of 241 patients) for cases that were not treated, 61% (324 of 532) for cases treated with amphotericin B deoxycholate, 57% (51 of 90) for cases treated with surgery alone, and 70% (328 of 470) for cases treated with antifungal therapy and surgery. By multivariate analysis, infection due to Cunninghamella species and disseminated disease were independently associated with increased rates of death (odds ratios, 2.78 and 11.2, respectively). CONCLUSIONS: Outcome from zygomycosis varies as a function of the underlying condition, site of infection, and use of antifungal therapy.

Antifungal Agents↗

Outbreak of dysentery associated with ceftriaxone-resistant Shigella sonnei: First report of plasmid-mediated CMY-2-type AmpC beta-lactamase resistance in S. sonnei.

We document the first report of plasmid-encoded CMY-2-type AmpC beta-lactamase identified among Shigella sonnei isolates resistant to ceftriaxone and obtained after an outbreak of bacillary dysentery in Taiwan. One hundred eighty-two children in two elementary schools in Yu-Li, Taiwan, where an outbreak occurred after a typhoon hit this area in 2001, were enrolled in this study. Clinical and epidemiologic data on the infected children were collected. Pulsed-field gel electrophoresis (PFGE) was performed on the isolates to determine the genetic relatedness of outbreak strains. Plasmid analysis and PCR were performed to identify beta-lactamase genes responsible for ceftriaxone resistance. Forty-seven children from the two elementary schools were culture positive for S. sonnei in this outbreak. Twenty-three children were asymptomatic. Of the total isolates 55.3% were resistant to ampicillin. One hundred percent of the isolates obtained from children in school A were initially susceptible to both ampicillin and ceftriaxone. Of isolates obtained from school B 96.2% were nonsusceptible to ceftriaxone. However, two isolates from school A developed resistance to ampicillin during the course of treatment. All 18 available isolates showed closely related PFGE patterns (4, 4a, 4b, and 4c). CMY-2-type AmpC beta-lactamase was responsible for ceftriaxone resistance in ceftriaxone-nonsusceptible isolates; Southern blot hybridization confirmed that such a resistance gene was located on the plasmid. This is the first report of plasmid-mediated CMY-2-type AmpC beta-lactamase in S. sonnei. Ampicillin-resistant isolates can develop during the course of antibiotic treatment.

Adolescent↗

Nontyphoid salmonellosis in taiwan children: clinical manifestations, outcome and antibiotic resistance.

OBJECTIVES: The purposes of this study were to investigate the epidemiologic, clinical, and microbiologic features of patients with nontyphoid salmonellosis and to elucidate the impact of resistance on the outcome of nontyphoid salmonellosis in Taiwan. The authors also sought to develop a severity score to derive an objective guideline for antibiotic use in nontyphoid salmonellosis in the era of increasing antibiotic resistance. METHODS: The authors prospectively monitored 311 children with nontyphoid salmonellosis in Kaohsiung, Taiwan. The demographic, clinical, and microbiologic features, underlying diseases, treatment regimen, complications, and outcome were analyzed. In vitro susceptibility testing of the isolates was performed. RESULTS: The median age of affected patients was 15 months. Salmonella enteritidis B caused 68.5% of episodes, followed by S. enteritidis C1 (11.9%), D (7.7%), C2 (7.1%), E (2.6%), S. choleraesuis (1.6%), and S. paratyphi (0.6%). Sixty percent of isolates were resistant to ampicillin. Patients with bacteremia could not be differentiated from patients without bacteremia on clinical grounds. Patients receiving antibiotics that were inactive in vitro (discordant therapy) had more days of fever and longer hospital stay compared with patients receiving antibiotics that were active in vitro (concordant therapy). Patients receiving no antibiotic treatment had the fewest days of fever and shortest hospital stays, especially among patients with mild illness (severity score, 0-1). CONCLUSION: Blood culture should be obtained in patients with nontyphoid salmonellosis to detect bacteremia. In treating antibiotic-resistant nontyphoid salmonellosis, antibiotics are still not mandatory for patients who present with primarily gastrointestinal symptoms and limited signs of systemic inflammation reflected by a low severity score (low C-reactive protein, fewer band cells in peripheral blood, and fewer days of fever before admission). Susceptibility data should be promptly obtained because use of discordant antibiotics appears to prolong illness.

Adolescent↗

Necrotizing pneumonitis caused by Mycoplasma pneumoniae in pediatric patients: report of five cases and review of literature.

Mycoplasma pneumoniae infection is usually self-limited without severe sequelae. We report 5 pediatric patients with necrotizing pneumonitis caused by Mycoplasma pneumoniae and reviewed the reported cases in the English language. Protracted course of fever and respiratory distress were noted in all 5 patients. Macrolides and adequate chest tube drainage for pleural effusion were the mainstay of treatment.

Adolescent↗

Newer systemic antifungal agents : pharmacokinetics, safety and efficacy.

The past few years have seen the advent of several new antifungal agents, including those of a new class and a new generation of an existing class. Caspofungin, the first available echinocandin, has greatly expanded the antifungal armamentarium by providing a cell wall-active agent with candidacidal activity as well as demonstrated clinical efficacy in the therapy of aspergillosis refractory to available therapy. In addition, in clinical trials, caspofungin had comparable efficacy to amphotericin B for candidaemia and invasive Candida infections. Caspofungin and two more recently introduced echinocandins, micafungin and anidulafungin, are available as intravenous formulations only and characterised by potent anti-candidal activity, as well as few adverse events and drug interactions. Voriconazole, the first available second-generation triazole, available in both intravenous and oral formulations, has added a new and improved therapeutic option for primary therapy of invasive aspergillosis and salvage therapy for yeasts and other moulds. In a randomised trial, voriconazole demonstrated superior efficacy and a survival benefit compared with amphotericin B followed by other licensed antifungal therapy. This and data from a noncomparative study led to voriconazole becoming a new standard of therapy for invasive aspergillosis. Voriconazole has several important safety issues, including visual adverse events, hepatic enzyme elevation and skin reactions, as well as a number of drug interactions. Posaconazole, only available orally and requiring dose administration four times daily, shows encouraging efficacy in difficult to treat infections due to zygomycetes. Ravuconazole, available in both intravenous and oral formulations, has broad-spectrum in vitro potency and in vivo efficacy against a wide range of fungal pathogens. Clinical studies are underway. Despite the advances offered with each of these drugs, the morbidity and mortality associated with invasive fungal infections remains unacceptable, especially for the most at-risk patients. For individuals with severe immunosuppression as a result of chemotherapy, graft-versus-host disease and its therapy, or transplantation, new drugs and strategies are greatly needed.

Animals↗

Esophageal candidiasis in human immunodeficiency virus-infected pediatric patients after the introduction of highly active antiretroviral therapy.

OBJECTIVE: To investigate epidemiologic trends, clinical features and outcome of esophageal candidiasis in the era of highly active antiretroviral therapy in a prospectively monitored population of HIV-infected children and adolescents followed at the National Cancer Institute. PATIENTS AND METHODS: The records of all HIV-infected pediatric patients (n = 266) followed between 1995 and 2000 were reviewed for a history of esophageal candidiasis. Proven esophageal candidiasis was defined as clinical plus radiographic and/or endoscopic findings of esophageal candidiasis. Probable esophageal candidiasis was defined as esophageal symptoms that responded promptly to appropriate antifungal therapy. The medical records of all patients fulfilling these criteria were reviewed for demographic, clinical and laboratory features at presentation, as well as therapeutic interventions and outcome. RESULTS: Of the 266 patients 9 (3.4%) had 18 documented episodes of proven (n = 16) or probable (n = 2) esophageal candidiasis. A history of prior mucosal candidiasis was present in 94% of all episodes. The median CD4+ count at the time of diagnosis was 7/microl (range, 0 to 550), and the median viral load was 98000 copies/ml (range, 22916 to 1278933). Concurrent oropharyngeal candidiasis was the most common clinical presentation (72%) followed by fever (55%), odynophagia (50%) and nausea or vomiting (39%). Treatment consisted of antifungal triazoles (61%) or amphotericin B (39%). Clinical cure was achieved in 15 cases, including all patients receiving triazoles. CONCLUSION: Esophageal candidiasis persists in the subgroup of patients not responding to highly active antiretroviral therapy and in that setting may present without concomitant oropharyngeal candidiasis or typical clinical symptoms, thus underscoring the need for a high index of suspicion in children with very low CD4+ counts.

Adolescent↗

Safety, pharmacokinetics, and pharmacodynamics of cyclodextrin itraconazole in pediatric patients with oropharyngeal candidiasis.

The safety, pharmacokinetics, and pharmacodynamics of cyclodextrin itraconazole (CD-ITRA) oral suspension were investigated in an open sequential dose escalation study with 26 human immunodeficiency virus (HIV)-infected children and adolescents (5 to 18 years old; mean CD4(+)-cell count, 128/microl) with oropharyngeal candidiasis (OPC). Patients received CD-ITRA at either 2.5 mg/kg of body weight once a day (QD) or 2.5 mg/kg twice a day (BID) for a total of 15 days. Pharmacokinetic sampling was performed after the first dose and for up to 120 h after the last dose, and antifungal efficacy was evaluated by standardized scoring of the oropharynx. Apart from mild to moderate gastrointestinal disturbances in three patients (11.5%), CD-ITRA was well tolerated. Two patients (7.6%) discontinued treatment prematurely due to study drug-related adverse events. After 15 days of treatment, the peak concentration of drug in plasma (C(max)), the area under the plasma concentration-time curve (AUC) from 0 to 24 h (AUC(0-24)), the concentration in plasma at the end of the dosing interval (predose) (C(min)), and the terminal half-life of itraconazole (ITRA) were (means and standard deviations) 0.604 +/- 0.53 microg/ml, 6.80 +/- 7.4 microg. h/ml, 0.192 +/- 0.06 microg/ml, and 56.48 +/- 44 h, respectively, for the QD regimen and 1.340 +/- 0.75 microg/ml, 23.04 +/- 14.5 microg. h/ml, 0.782 +/- 0.19 microg/ml, and 104.22 +/- 94 h, respectively, for the BID regimen. The mean AUC-based accumulation factors for ITRA on day 15 were 4.14 +/- 0.9 and 3.53 +/- 0.6, respectively. A comparison of the dose-normalized median AUC of the two dosage regimens revealed a trend toward nonlinear drug disposition (P = 0.05). The mean metabolic ratios (AUC of hydroxyitraconazole/AUC of ITRA) at day 15 were 1.96 +/- 0.1 for the QD regimen and 1.29 +/- 0.2 for the BID regimen, respectively (P < 0.05). The OPC score (range, 0 to 13) for all 26 patients decreased from a mean of 7.46 +/- 0.8 at baseline to 2.8 +/- 0.7 at the end of therapy (P < 0.001), demonstrating antifungal efficacy in this setting. The relationships among C(max), C(min), AUC(0-12), C(max)/MIC, C(min)/MIC, AUC(0-12)/MIC, time during the dosing interval when the plasma drug concentrations were above the MIC for the infecting isolate, and the residual OPC score at day 15 for the entire study population fit inhibitory effect pharmacodynamic models (r, 0.595 to 0.421; P, <0.01 to <0.05). All patients with fluconazole-resistant isolates responded to treatment with CD-ITRA; however, there was no clear correlation between the MIC of ITRA and response to therapy. In conclusion, CD-ITRA was well tolerated and efficacious for the treatment of OPC in HIV-infected pediatric patients. Pharmacodynamic modeling revealed significant correlations between plasma drug concentrations and antifungal efficacy. Based on this documented safety and efficacy, a dosage of 2.5 mg/kg BID can be recommended for the treatment of OPC in pediatric patients > or =5 years old.

Adolescent↗

Endocarditis caused by penicillin-resistant Streptococcus mitis in a 12-year-old boy.

A case of congenital coronary arteriovenous fistula with infective endocarditis caused by penicillin-resistant Streptococcus mitis is reported. Lack of prophylactic antibiotics during dental procedure may cause the development of endocarditis. Bactericidal test (Schlichter test) was performed to guide the therapy for this case of bacterial endocarditis caused by penicillin-resistant viridans streptococci. This case highlights the importance of antibiotic prophylaxis in patients with underlying heart disease undergoing dental procedures.

Ampicillin↗

Pneumococcal infection in children: rational antibiotic choice for drug-resistant Streptococcus pneumoniae.

Streptococcus pneumoniae is one of the most common bacterial causes of otitis media, sinusitis, bacteremia, pneumonia and bacterial meningitis in the pediatric population. The resistance of S. pneumoniae to penicillin and other antimicrobial agents is increasing in many parts of the world. In Taiwan, extremely high prevalence (70%) of penicillin-resistant S. pneumoniae among children with nasopharyngeal carriage has been reported. The mechanism of resistance to penicillin is the alteration of penicillin binding protein (PBP) instead of the production of beta-lactamase. Thus beta-lactamase inhibitors are not the solution to the treatment of infections caused by penicillin-resistant S. pneumoniae. The adequate treatment of infections caused by penicillin-resistant S. pneumoniae should be based on (1) site of infection (2) degree of resistance. Currently, the MIC breakpoints for S. pneumoniae are divided to 2 categories; one for CNS infection and the other for non-CNS infections. For non-CNS infections caused by susceptible or intermediate S. pneumoniae, penicillin still remains the drug of choice with excellent bactericidal activity. Vancomycin should not be the first choice in treating all pneumococcal infections.

Adult↗