Diagnosis and Management of Sore Throat in Young Adults

Background: Sore throat is one of the most common presentations in primary care, especially in young adults. This thesis aimed to further research in the area of improving the diagnosis and management of sore throat in young adults, with a particular focus on infectious mononucleosis (IM) and Group A Beta Haemolytic Streptococcus (GABHS). There were four broad objectives; 1) to systematically review the effectiveness of antiviral therapy for infectious mononucleosis (IM), 2) to derive and externally validate a clinical prediction rule (CPR) to aid in the positive diagnosis of IM caused by Epstein Barr Virus (EBV), 3) to validate the Centor score CPR (a widely used CPR for the diagnosis of GABHS sore throat) in an Irish setting, and 4) to explore potential associations between IM caused by EBV and fatigue and time missed from college / work in younger adults.

Methods: A systematic review of the effectiveness of antivirals for IM was carried out, according to Cochrane methodology. A prospective cohort study with six-month follow-up was conducted in seven student health centres in Ireland. A CPR for the diagnosis of EBV was developed and internally validated in the thesis cohort and externally validated in a geographically separate cohort. The Centor score CPR was validated in this research cohort. The cohort study data was also used to explore outcomes (fatigue scores and time missed from college or work) of participants diagnosed with EBV IM versus those with sore throat from other aetiology. 

Results: The systematic review included seven randomised controlled trials (RCTs) with a total of 333 participants. There were small statistically significant improvements in the treatment group for two of the twelve outcomes; 'time to clinical recovery as assessed by physician' and 'duration of lymphadenopathy, however these may not be clinically meaningful. A total of 348 young adults (42 (12.8%) EBV positive) were recruited to the cohort study. Response rates at three month follow up were 68.7% and at six month follow up were 56.3%, with similar rates in EBV positive and EBV negative participants. Four CPR models were developed for the diagnosis of EBV. The models performed reasonably well in internal validation and similarly when validated externally. When the Centor score was validated in this study population, it was found to have only fair performance. The cohort study was underpowered,  but a large percentage of those in both EBV and non-EBV sore throat groups (56% and 42% respectively) reported fatigue six months following acute illness. The odds ratio for missing 10 or more days (compared to 0-9 days) for EBV positive versus EBV negative patients was 3.58 (95% CI 1.47 to 8.71).

Conclusions: The presentation of sore throat is a very common one in primary care. This thesis adds to the literature in the area by examining its diagnosis and management in young adults, especially focussing on two conditions; IM caused by EBV and GABHS sore throat. This thesis describes tools that can aid in the diagnostic process, suggests strategies for management, depending on which underlying pathology is suspected and highlights evidence gaps in the management of IM.