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T Zaoutis

Publications and source records attributed to T Zaoutis.

7 recordsLinked to original sources
PubMed2004

The role of group C and group G streptococci in acute pharyngitis in children.

Group C streptococci (GCS) and group G beta-haemolytic streptococci (GGS) have caused well-documented epidemics of acute pharyngitis in children, but the importance of these organisms in causing endemic or sporadic pharyngitis is uncertain. The heterogeneity of GCS and GGS may obscure the role of certain subtypes, such as the large-colony-forming strains of group C (Streptococcus dysgalactiae subsp. equisimilis) or group G, in endemic pharyngitis. For a 1-year period, children (aged 6 months to 18 years) (n = 2085) who presented with pharyngitis to the children's hospital emergency department and two outpatient offices were enrolled in a cross-sectional study to ascertain the role of large-colony-forming GCS and GGS in acute pharyngitis. Control patients (n = 194) were children who presented to the same locations during the same time period with non-respiratory tract symptoms or to the orthopaedic cast clinic. Throat cultures were obtained by a standard reference method, and swabs were plated on Strep-Selective Agar. Lancefield grouping and species identification was performed on all beta-haemolytic isolates. In total, 65 (3%) large-colony-forming GCS and GGS strains were obtained from pharyngitis patients, and three (1.5%) were obtained from the control group (odds ratio 2.0; 95% confidence interval 0.6-6.1). The low isolation rate of large-colony-forming strains of GCS and GGS indicates that even if these organisms are associated with acute, sporadic pharyngitis in paediatric patients, they represent an unusual pathogen.

Acute Disease↗
PubMed2001

Performance of a predictive model for streptococcal pharyngitis in children.

CONTEXT: Group A beta-hemolytic streptococcus (GABHS) pharyngitis is a common childhood illness. The clinical diagnosis is difficult to determine and laboratory tests have limitations; hence, the condition is generally overdiagnosed and overtreated. Several clinical pediatric-specific predictive models have been published but none have been prospectively studied. OBJECTIVE: To test the performance of a previously published predictive model for GABHS pharyngitis in children in different clinical settings and during different seasons. DESIGN: Prospective cohort study. SETTINGS: Pediatric emergency department and 2 pediatric outpatient clinics. PATIENTS: Children aged between 1 and 18 years with pharyngitis on initial examination at study sites between April 1, 1999, and March 31, 2000. INTERVENTIONS: Recording of clinical features during initial evaluation using a standardized form and recovery of GABHS from patients' throats using reference standard methods. MAIN OUTCOME MEASURES: Posttest probability for GABHS positive throat culture associated with the model's positive predictors (moderate to severe tonsillar swelling, cervical lymphadenopathy [moderate to severe tenderness and enlargement of cervical lymph nodes], scarletiniform rash, and the absence of coryza) and the models' negative predictors (absence of the above signs and the presence of coryza). RESULTS: Of 587 patients analyzed, 218 (37%) had a positive throat culture for GABHS. Forty-nine percent were boys. Mean +/- SD age was 6.7 +/- 3.9 years. There was no difference between the subsets within the sample. The posttest probability values for a positive throat culture associated with positive and negative predictors of the model were 79% and 12%, respectively. CONCLUSIONS: A pediatric predictive model for GABHS pharyngitis performed better than physicians' subjective estimates for a positive throat culture and was comparable with a rapid antigen detection test. The model performed consistently well in different populations and across seasons. It can be useful if reliable microbiological testing and/or follow-up are not attainable.

Adolescent↗
PubMed2001

In vitro activities of linezolid, meropenem, and quinupristin-dalfopristin against group C and G streptococci, including vancomycin-tolerant isolates.

The in vitro activities of meropenem, linezolid, quinupristin-dalfopristin, vancomycin, and penicillin against 130 clinical isolates of group C and G streptococci, including vancomycin-tolerant isolates, were evaluated. Meropenem, linezolid, quinupristin-dalfopristin, vancomycin, and penicillin MICs at which 90% of the isolates were inhibited were 0.06, 2.0, 0.25, 0.5, and < or = 0.016 microg/ml, respectively. Meropenem, linezolid, quinupristin-dalfopristin, and penicillin were active against group C and G streptococci, including vancomycin-resistant strains.

Acetamides↗
PubMed1999

Multivariate predictive models for group A beta-hemolytic streptococcal pharyngitis in children.

OBJECTIVES: To create predictive models for the clinical diagnosis of group A beta-hemolytic streptococcal (GABHS) pharyngitis in children. METHODS: Patients aged 6 months to 18 years presenting to a pediatric ED with suspected GABHS pharyngitis were prospectively enrolled in the study. Clinicians recorded pertinent clinical information using a standardized form and obtained a throat swab to culture GABHS using a reference standard method. Twelve demographic and clinical features of patients with positive throat cultures were compared with the features of patients with negative throat cultures. Significantly different features were entered in a stepwise logistic regression analysis to create predictive models for the diagnosis. RESULTS: Eighty-five patients (29%) were culture-positive and 212 (71%) were culture-negative for GABHS. Respective mean ages were 6.2 years and 6.1 years in the two groups. Univariate chi-square analysis of the 12 features identified six variables that were significantly associated with GABHS. All significant features were initially included in a stepwise logistic regression analysis. In model I, four independent variables were identified: moderate to severe presentation of tonsillar swelling, moderate to severe tenderness and enlargement of cervical lymph nodes, the presence of scarlatiniform rash, and the absence of moderate to severe coryza, yielding a 95% probability for GABHS. Excluding the rare scarlatiniform rash, the remaining variables were used in the second regression analysis. In model II, three independent variables were identified: moderate to severe tonsillar swelling, moderate to severe tenderness and enlargement of cervical lymph nodes, and absence of moderate to severe coryza, yielding a probability of 65% for the diagnosis. A probability of <15% was observed in the absence of scarlatiniform rash, the absence of moderate to severe tenderness and enlargement of cervical lymph nodes, and the presence of moderate to severe coryza. CONCLUSIONS: In children with moderate to severe presentation of tonsillar swelling, tenderness and enlargement of cervical lymph nodes, and the absence of coryza, the probability of a positive throat culture is >65%. Conversely, in the absence of a moderate to severe presentation of tonsillar swelling, enlargement of cervical nodes, and the presence of coryza, the probability of a positive throat culture is <15%. If prospectively validated, these models could be integrated into a consistent treat, test, and no treatment/no testing approach to the clinical management of childhood pharyngitis.

Adolescent↗
PubMed1999

Antibiotic susceptibilities of group C and group G streptococci isolated from patients with invasive infections: evidence of vancomycin tolerance among group G serotypes.

A retrospective review of medical records for 32 patients with invasive group C streptococcus (GCS) or group G streptococcus (GGS) infections was performed. MICs and minimum bactericidal concentrations (MBCs) of penicillin, erythromycin, and vancomycin for all isolates were obtained. Tolerance of vancomycin, defined as an MBC 32 or more times higher than the MIC, was exhibited by 18 GGS isolates (54%). The identification of tolerance in clinical isolates of GGS and GCS may have clinical implications in treating these seriously ill patients.

Adult↗