tonsillitis

introduction

most cases of inflamed tonsils and pharyngitis even with purulent exudate are viral and are often difficult to distinguish clinically from Group A Streptococcal infections
Streptococcal infections are more common in those aged 3yrs to 13yrs and less so in older children and adults
In children under 3 yrs, the far majority of throat infections are viral.
throat swabs are generally of little utility if gonococcal disease is very unlikely as many have Streptococci in the pharynx without it being causative
When assessing patients with a sore throat, you need to exclude peritonsillar abscess (quinsy) and EBV / glandular fever / infectious mononucleosis and also some important rare but potentially lethal conditions such as:
- retropharyngeal abscess
  - this is suggested by presence of stridor or a stiff neck (refusal to flex the neck)
- epiglottitis - now very rare in vaccinated children which has eradicated invasive HiB disease
  - this is suggested by unvaccinated children with stridor and minimal cough
  - if you suspect this in a child, Do NOT examine the throat as this risks sudden airway obstruction
- scarlet fever
  - this is suggested by features such as a classic scarlatiform rash, strawberry tongue and palatial petechiae
- Ludwig's angina
  - usually in older adults and presents with swelling to the floor of the mouth
- diphtheria now exceedingly rare as most are vaccinated
other differentials to consider:
- gonococcus - becoming more prevalent in young adults, especially men who have sex with men
- candida fungal infection / thrush - especially in young children, or in immunocompromised adults
- some specific viral causes of pharyngitis:
  - herpangina - ulcers on the soft palate
  - Herpes simplex virus (HSV) gingivostomatitis - ulcers in anterior half of mouth and tongue
  - aphthous mouth ulcers
  - hand, foot and mouth disease - may have purplish vesicles on hands and feet, and in infants, a m/p rash on buttocks
  - fifth disease / slapped cheek syndrome / eythema infectiosum - slapped cheek appearance +/- mottly web-like rash to medial aspect upper arms and is caused by Parvovirus B19 which can be an issue for pregnant women

if stridor is present, it is unlikely to be tonsillitis - see stridor
AVOID antibiotics if likely to be viral
HOWEVER, antibiotics should be given for high risk patients such as:
- communities with high prevalence of rheumatic fever and patients is aged 2-25yrs old
- past history of rheumatic fever
- signs of scarlet fever or quinsy
- probable acute bacterial tonsillitis especially if requiring admission to hospital

ED Mx of presumed bacterial tonsillitis

examine specifically for:
- evidence of EBV / glandular fever / infectious mononucleosis - posterior cervical LNs, hepatomegaly, splenomegaly
- evidence of peritonsillar abscess (quinsy)
FBE, U&Es, CRP, LFTs, IM screen
if suspected quinsy, admit and discuss with ENT as may need aspiration
if suspected glandular fever, then see EBV / glandular fever / infectious mononucleosis
otherwise:
- admit to ED observation unit if either:
  - significant dysphagia
  - unable to tolerate oral antibiotics
  - dehydrated
  - failed oral antibiotics and unwell
  - potential airway risk
- iv fluids
- iv benzyl penicillin
- consider iv dexamethasone
- discharge home on a 10 day course of either:
  - oral phenoxymethylpenicillin (Pen V) bd (qid is not needed) but this needs to be taken before food
  - oral amoxycillin tds, better absorbed and better compliance but do not use if suspect EBV / glandular fever / infectious mononucleosis as a rash is likely to occur, and being broad spectrum, is more likely to cause diarrhoea or thrush and general antibiotic resistance issues than Pen V - thus this is NOT recommended as 1st line Rx.
  - if allergic to penicillins, then oral cephalexin qid, or if severe allergy, consider a macrolide such as roxithromycin
- if suspect or proven EBV / glandular fever / infectious mononucleosis then warn about avoiding contact sports as risk of splenic rupture if enlarged.