title: [Incidence of streptococcal pharyngitis].
abstract: OBJECTIVE
  To determine the incidence of streptococcal pharyngitis in patients younger than 2 years of age, and to evaluate the role of group C streptococci as a pathogenic agent in acute pharyngitis through throat culture in symptomatic patients.
  
  
  METHODS
  We performed a retrospective descriptive study of patients with clinical symptoms of acute pharyngitis and fast detection of streptococcal antigen and/or exudate culture who attended the emergency department between February 2004 and February 2005.
  
  
  RESULTS
  Group A beta-hemolytic streptococcus (GAS) was isolated by pharyngeal culture in 85 patients aged less than 2 years (12.6%). In these patients the fast test displayed lower sensitivity and positive predictive value (PPV) (sensitivity: 78%; PPV: 69%, p < 0.01). Patients aged less than 2 years had a greater frequency fever, exanthema and catarrhal symptoms than older children (p < 0.01). In the younger age group, erythromycin resistance rates increased to 24.7% (p = 0.08). Group C streptococcus was isolated in 5.2% (43 patients). The most frequent reason for consultation was fever (74.4%) and the most common findings on examination were abnormal pharynx in 90.7%, odynophagia and adenopathies in 55.8%. Two incidence peaks (in May and September) were observed, with sporadic cases throughout the year.
  
  
  CONCLUSIONS
  In our sample, the percentage of GAS in patients aged less than 2 years was higher than that reported in other series. In this age group, the sensitivity of the fast test is lower than in other age groups and there is a higher rate of erythromycin resistance. The percentage of tonsillitis due to serotype C was also slightly higher than expected. Two peaks of incidence were observed, similar to those occurring with SGA, with sporadic cases throughout the year.
authors.affiliation: Sección de Urgencias, Hospital Materno-Infantil Gregorio Marañón, Madrid, España. anitapenalba@hotmail.com
authors.forename: A C
authors.initials: AC
authors.lastname: Peñalba Citores
authors.forename: B
authors.initials: B
authors.lastname: Riaño Méndez
authors.forename: R
authors.initials: R
authors.lastname: Marañón Pardillo
authors.forename: C
authors.initials: C
authors.lastname: Míguez Navarro
authors.forename: P
authors.initials: P
authors.lastname: Vázquez López
authors.forename: María M
authors.initials: MM
authors.lastname: Guerrero Soler
authors.forename: C
authors.initials: C
authors.lastname: Merello Godino
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D006801:Humans; D015994:Incidence; D007223:Infant; D010612:Pharyngitis / Q000453:epidemiology* / Q000382:microbiology*; D012189:Retrospective Studies; D013290:Streptococcal Infections / Q000453:epidemiology*