title: Over prescription of antibiotics for adult pharyngitis is prevalent in developing countries but can be reduced using McIsaac modification of Centor scores: a cross-sectional study.
abstract: BACKGROUND
  Although Group A beta hemolytic streptococcus (GABHS) can cause bacterial pharyngitis, the most common etiology is viral; despite this viral etiology, antibiotics are commonly prescribed for this infection in industrialized countries. We investigated the prevalence of GABHS in adult pharyngitis patients from lower socioeconomic settings in Karachi, Pakistan, how often antibiotics are prescribed for pharyngitis and if appropriate agents were used in a developing world setting. Finally, we wanted to see the usefulness of modified McIsaac scores in predicting positive cultures.
  
  
  METHODS
  Adult patients were recruited from three local hospital outpatient dispensaries (OPDs). All patients aged 14-65 years who were suspected of having bacterial pharyngitis had throat swabs taken. Laboratory results for GABHS pharyngitis were then compared with their prescriptions. Appropriateness (using the World Health Organization's definition) and type of antibiotic prescribed were assessed.
  
  
  RESULTS
  Of 137 patients, 30 patients each were studied for scores of 0, 1, 2 and 3; 17 patients were studied for score 4. Although 6 (4.4%) patients were GABHS+, for a prevalence of 43.8 per 1000 population, antibiotics were prescribed to 135 patients (98.5%). Of these, only 11.1% received appropriate antibiotics while 88.9% received inappropriate antibiotics. Penicillins were prescribed most (34.1%), especially amoxicillin/clavulanate; followed by macrolides (31.1%), especially the second-generation agents, and fluoroquinolones (14.8%). McIsaac scores were found to be 100% sensitive and 68.7% specific, giving a positive predictive value (PPV) of 12.7% and a negative predictive value (NPV) of 100%.
  
  
  CONCLUSIONS
  Antibiotics were prescribed irrationally to adult pharyngitis patients, as most cultures were negative for bacterial infection. McIsaac modification of Centor scores related directly to culture results. We would therefore highly recommend its use to help family physicians make treatment decisions for adult pharyngitis patients.
authors.affiliation: Department of Pharmacology, University of Karachi, Karachi, Pakistan.
authors.forename: Amber Hanif
authors.initials: AH
authors.lastname: Palla
authors.forename: Rafeeq Alam
authors.initials: RA
authors.lastname: Khan
authors.forename: Anwar H
authors.initials: AH
authors.lastname: Gilani
authors.forename: Fawziah
authors.initials: F
authors.lastname: Marra
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002511:Cephalosporins / Q000627:therapeutic use; D003430:Cross-Sectional Studies; D003906:Developing Countries; D003937:Diagnosis, Differential; D003955:Diagnostic Tests, Routine / Q000379:methods*; D005260:Female; D006801:Humans; D057970:Inappropriate Prescribing / Q000517:prevention & control* / Q000639:trends*; D018942:Macrolides / Q000627:therapeutic use; D008297:Male; D008828:Microbiological Techniques; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010612:Pharyngitis / Q000175:diagnosis* / Q000188:drug therapy* / Q000209:etiology; D015995:Prevalence; D012680:Sensitivity and Specificity; D013290:Streptococcal Infections / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy*; D013291:Streptococcus / Q000302:isolation & purification; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D018942:Macrolides