Sore Throat (acute) Lawrence Pike

Sore Throat (acute)
Lawrence Pike
Definitions
• Pharyngitis
– predominantly inflammation of the oropharynx, but
not the tonsils.
• Tonsillitis
– when the tonsils are particularly affected.
• Laryngitis
– few signs of infection visible but the patient complains
of soreness lower down the throat often with a
hoarse voice.
Causes
• Viral (70-80%)
• Group A beta-haemolytic streptococcus
(20-30%)
Incidence
• Sore throat is estimated to account for
10% of all general practice consultations
• Asymptomatic carriage of
streptococcus
– is common with rates of 6 - 40%
– Carriers have low infectivity and are not at
risk of developing complications such as
rheumatic fever
Symptoms
• Sore throat
• Pain on swallowing
• Fever
• Headache
• Malaise
• Hoarseness if laryngeal involvement
Signs
• Redness of the pharynx and tonsils
• Presence of exudate
• Enlarged tonsils
• Swollen tender neck glands.
• Note that a streptococcal sore throat is
impossible to diagnose on clinical grounds
alone.
Scarlet Fever
• A red punctate skin eruption with
sandpaper-like texture
• Usually begins on chest and spreads to
abdomen and extremities
• Prominent in skin creases
• Flushed face with circumoral pallor
• Strawberry tongue
• These indicate a streptococcal infection
Investigations?
• Throat swabs cannot differentiate between "infection"
•
•
and "carriage", are poorly sensitive, and are therefore of
limited value. Results take up to 24 - 48 hours to be
reported, and the test is relatively expensive.
Rapid antigen tests to detect streptococcal antigen on
a throat swab are not easily available.
Anti-streptolysin O (ASO) titres can help to identify
whether a patient has recently been infected with
streptococcus, and may be useful for patients who
remain unwell or develop complications.
Differential Diagnosis
• Infectious mononucleosis (glandular
fever)
• Epiglottitis (requires urgent admission)
• Gonococcal pharyngitis (rare)
• Diphtheria (very rare in U.K)
• Neutropaenia (e.g. ensure patient not
on carbimazole)
Complications
• Otitis media
• Sinusitis
• Peritonsillar abscess (quinsy)
• Suppurative cervical adenopathy
• Rheumatic fever
• Post streptococcal glomerulonephritis
Management
• Sore throat (pharyngitis, tonsillitis,
laryngitis) is usually a self-limiting illness,
whether due to viral or bacterial infection.
• Explanation, reassurance and advice on
symptomatic treatment is frequently all
that is necessary when a patient consults
with a sore throat, as only a third clearly
want or expect an antibiotic.
Management
• Prescription of an antibiotic increases patient
•
•
•
reattendance rates for further episodes of sore throat.
The patient is also exposed to the risk of side effects
Increased risk of bacterial resistance in the community.
Antibiotic therapy of sore throat reduces duration of
symptoms by about 8 hours, although it is not known if
symptom severity is also affected. The absolute benefit
is small, with 90% of both treated and untreated
patients symptom free within one week.
Management
• Antibiotic therapy has a small protective
effect on the risk of developing sinusitis,
otitis media and possibly peritonsillar
abscess (quinsy).
– 30 children and 145 adults need treatment to
prevent one case of acute otitis media.
•]
Management
• Benefit in reducing the incidence of rheumatic
fever or post streptococcal glomerulonephritis is
likely to be low.
– The incidence of rheumatic fever and post
streptococcal glomerulonephritis has fallen in
industrialised countries and does not appear to be
related to antibiotic use. Although early studies
showed that antibiotic treatment decreased the risk of
these complications more recent studies have not
shown benefit.
Management
• Suggested indications for antibiotics are:
–
–
–
–
–
severely inflamed throat with marked systemic upset
confirmed streptococcal infection
scarlet fever
patients with impaired immunity (splenectomy)
past history of rheumatic fever or post-streptococcal
glomerulonephritis.
– Antibiotic treatment is also usually advised during
outbreaks of streptococcal infection in communities
such as schools, hostels or prison (public health).
Management
• If an antibiotic is necessary
– Penicillin is the treatment of choice, with erythromycin
in patients with penicillin allergy. 10 days treatment is
recommended in order to eradicate possible
streptococcus infection. [DTB 1995]
• Tonsillectomy is occasionally recommended for
recurrent attacks of tonsillitis. Consider only if
seven documented throat infections in the
preceding year, or three in each of three
successive years.