The Hurty Throat

An acutely inflamed pharynx with enlarged tonsils and prominent exudate.

Common Causes:

• Tonsillitis
• Pharyngitis
• Peritonsilar Abscess (quinsy)
• Infectious mononucleosis

Most patients with sore throat will have a viral or short-lived bacterial infection. However, clinicians need to be able to identify patients at risk of having group A beta-hemolytic streptococcal infections as appropriate treatment may prevent complications.

Other less common bacterial causes of pharyngitis/ tonsilitis include:

• group C and G strep, Fusobacterium necrophorum, Neisseria gonorrhoea, Corynebacterium diphtheriae, Mycoplasma pneumoniae, and several chlamydial species

Less common and/or dangerous causes of a sore throat include:

• Lemierre syndrome due to Fusobacterium necrophorum
• Retropharyngeal abscess
• Epiglottis
• Scarlet fever
• Diptheria
• Bacterial Tracheitis
• Ludwig Angina
• Angioedema or anaphylaxis
• Painful cervical lymphadenopathy
• Trauma, e.g. foreign body or caustic ingestion

The Centor criteria were designed as a tool to determine the likelihood of that patient  having a group A streptococcal throat infection. It takes into account selected signs and symptoms in patients with pharyngitis.

The criteria consist of the following 4 signs and symptoms (1 point for each):

• History of fever
• Anterior cervical adenopathy
• Tonsillar exudates
• The absence of a cough

The modified criteria were developed to take into account age, based on the fact that children have a higher probability than adults of developing a step infection.

• 3-14 years old = add 1 point
• 15-44 years old  = 0 points
• > 44 years old + subtract a point

The score indicates the need for throat cultures and antibiotics:

• <2 points — No antibiotic or throat culture necessary.
  (Risk of strep infection <10%)
• 2-3 points — Should receive a throat culture and treat with an antibiotic if culture is positive.
• >3 points — Treat empirically with an antibiotic.
  (Risk of strep infection >50%)

This is based on a typical adult prevalence rate of 5-15% for group A streptococcus infection. For a simple and easy way to calculate the Centor criteria check out MDCalc.com.

Note: In countries with low rates of group A streptococcal infections — except in certain at risk groups — and the limited benefit of antibiotics, the Centor criteria are not typically used e.g. Australia.

The therapeutic goals of antibiotic treatment for pharyngitis/tonsillitis are:

• To shorten the acute illness.
• To prevent nonsuppurative complications (e.g. acute rheumatic fever, acute glomerulonephritis)
• To prevent suppurative complications (e.g. acute otitis media, quinsy, acute sinusitis)

The role of antibiotics in the treatment of patients with sore throats is an ongoing controversy

There is limited evidence suggesting that 1 in 9 patients will get some benefit from antibiotics (symptoms resolve about 16 hours sooner).

However 1 in 5 patients prescribed antibiotics will suffer from an adverse outcome (e.g rash, diarrhoea). Also, although rare,  people can develop life-threatening anaphylaxis from antibiotics. Furthermore, the majority of  patients will have short lived infections lasting only 3-4 days and complications of infection are rare.

Based on this, antibiotics should not be routinely given for sore throats.

Patients may present requesting antibiotics for their sore throat, in the hope that this will clear up the infection and relieve the pain. However, a recent study suggested that patients that present requesting antibiotics in reality actually simply want appropriate treatment for their pain [van Driel et al]

In Australia, antibiotics are recommended to prevent nonsuppurative complications in the following high-risk populations:

• patients aged 2 to 25 years with sore throat in communities with a high incidence of acute rheumatic fever (e.g. some Indigenous communities in central and northern Australia, and some other underprivileged communities)
• patients of any age with existing rheumatic heart disease
• patients with scarlet fever.

Antibiotics are also often given to patients being admitted to hospital with sore throat — this is a sicker group of patients and admitting teams generally like to do something…

Penicillin is still the antibiotic of choice in Australia:

• Phenoxymethylpenicillin 500mg (child:15 mg/kg up to 500mg) orally, 12-hourly for 10 days.
• 12 hourly dosing is preferred as it improves treatment compliance, and still is effective for streptococcal pharyngitis.

In poorly compliant patients, or those intolerant of oral therapy:

• Benzathine penicillin 900mg, IM as a single dose
• Dose varies for children based on body weight

Patients that are allergic to penicillin:

• Roxithromycin 300mg orally, every 12 hours for 10 days [Children: 4mg/kg up to 150mg every 12 hours for 10 days]

The trouble with being a hypochondriac these days is that antibiotics have cured all the good diseases.

Caskie Stinnett

Steroids should be considered in patients with severe pain or tonsillar swelling.

• Multiple studies have shown that steroids are  effective at reducing the clinical symptoms and shortening the course of the illness in severe cases, and should be reserved for patients with severe swelling or odynophagia.
• Adverse events are rare from steroid use, however does place some patients at risk of deranged glycaemic control, and gastrointestinal bleeding.
• Often single doses of either prednisolone or dexamethasone (e.g. 10mg in adults) is as effective as a short course.

However, in minor cases of pharyngitis/tonsillitis, steroids have only been shown to decrease pain by around 6 hours compared to antibiotics and analgesia — the risk-benefit balance is less clear in this setting.

Benefits of using steroids include:

• improvement of clinical symptoms
• Relieves swelling
• Provides analgesia
• Shortens the clinical course

Pharyngitis can be extremely painful for patients and limit their ability to swallow.

Some case studies suggest that a reason why patients return to ED two or three days later with dehydration is because of inadequate analgesia provision on earlier visits.

There is little evidence available to determine the most effective way to provide analgesia to patients.

Start simple:

• Paracetamol 500mg-1g 4 x day
• Ibuprofen 200-400mg 3 x day (one study suggested that ibuprofen gave better pain relief at 48 hours compared to paracetamol 80% vs 70.5%)
• Topical anaesthetic lozenges can provided short acting pain relief and a generally well tolerated and received by patients

During examination:

• Topical anaesthetic sprays (e.g. co-phenylcaine) provide effective quick analgesia, and can improve compliance with your exam.

For severe pain:

• Use opioids if necessary — try codeine first; if ineffective consider oxycodone.
• Both codeine and oxycodone are available in liquid forms.

• Driel, M. et.al. Are sore throat patients who hope for antibiotics actually asking for pain relief. Ann Fam Med. 2006 Nov-Dec;4(6):494-9. [PMC1687169]
• Hayward, G. et.al. Corticosteroids for pain relief in sore throat: systematic review and meta-analysis. BMJ. 2009 ;339:b2976 [PMC2722696]