Is the VIDAS B . R . A . H . M . S PCT assay able to detect a bacterial throat infection?

1. Is the VIDAS B.R.A.H.M.S PCT assay able to detect a bacterial throat infection? Mr Ajith P George MBChB, MRCS, DO-HNS ENT SpR

2. Overview • Aims & Objectives • Background • Methodology • Further investigations

3. Aims • 1- To establish whether the VIDAS BRAHMS PCT assay is sensitive enough to detect a proven bacterial infection of the throat • 2- To establish whether PCT rises following routine tonsillectomy • 3- To determine whether post tonsillectomy secondary haemorrhage (PTSH) is associated with a bacterial infection

4. Objectives • To reduce routine unnecessary prescription of antibiotics in ENT. • Reduce Cost • Decrease incidence of allergic reactions • Decrease side effects of medication • Slow the progression of antibiotic resistance

5. Background • Unnecessary antibiotic prescribing is leading to an increase in bacterial resistance1 • Procalcitonin in the management of LRTI’s has been demonstrated to • Reduce antibiotic prescribing2 • Decrease antibiotic cost per patient2 • Patients admitted for PTSH to ENT units across the UK are routinely prescribed antibiotics • There is no clear evidence to suggest PTSH is associated with a bacterial infection3

6. What is Procalcitonin? • 116 AA polypeptide pro-hormone of calcitonin • Produced in c-cells • Released from the liver during the acute phase response • Bacterial specific marker of infection- Levels related to severity

7. Current applications of PCT • Managing LRTI • Acute exacerbation of COPD • Differentiating viral and bacterial meningitis • Pneumonia sepsis induced ARDS • PUO • Differentiating sterile and infective pancreatitis

8. Evidence for PCT benefit • Christ-Cain et al compared PCT based therapeutic strategy against conventional management • N=243, Single blinded cluster RCT (119 standard group and 124 PCT group)

9. Management • Hx, examination, TPR, FBC, U&E’s, CXR, MC&S, ABG’s, Spirometry, Bronchoscopy

10. Outcomes of Christ-Cain et al • P>0.05 • QOL • VAS • WCC • CRP • Admission • Hospital stay • Death • ITU • P<0.05 • Antibiotic prescription • Duration of antibiotic prescription • Antibiotic cost per patient

11. Methodology • Stage I • A cross sectional analysis to establish a mean PCT level for patients with a proven bacterial throat infection • To determine whether the assay is sensitive enough • Stage II • A case control study to determine whether a significant difference exists in mean PCT levels of post tonsillectomy patients (control) against patients with a bacterial throat infection • To determine whether tonsillectomy causes a rise in PCT • Stage III • A case control study to determine a significant difference in mean PCT levels of PTSH patients against post tonsillectomy patients (control) • To establish whether PTSH is associated with a bacterial infection and therefore justifies antibiotic prescription

12. Further Investigations • Do patients admitted with Glandular Fever Justify antibiotic prescription? • Determining between viral and bacterial acute otitis media in children • Differentiating bacterial or inflammatory causes of acute salivary gland disease • Investigating the use of high sensitive PCT to determine if bipolar tonsillectomy is more traumatic than the cold steel technique.

13. Thank you!

14. References • 1-Cars O, Hogberg L, Murray M et al. Meeting the challenge of: A concerted global response is needed to tackle rising rates of antibiotic resistance. Without it, we risk returning to the pre-antibiotic era warn Otto Cars and colleagues.BMJ 2008; 337: a1438. • 2-Christ-Cain M, Jaccard-Stolx D, Bingisser R et al. Effect of Procalcitonin-guided treatment on antibiotic use and outcome in lower respiratory tract infections: cluster-randomised single-blinded intervention trial. The Lancet 2004; 363: 600-607 • 3-George A, Coulson C, De R. Procalcitonin: A bacterial specific marker of infection. Clinical Otolaryngology 2007; 32(4):310.