SKIN DISORDERS
General Medical Emergencies 117
(ii) Minor signs:
(a) inflammation or elevation
(b) bleeding or crusting
(c) sensory changes, including itching
(d) diameter ≥7 mm.
Table 2.9 Common exanthematous diseases
Disease Incubation
period
(days)
Prodrome Rash Other features and
infectivity
Chickenpox 10–20 None Macules,
papules,
vesicles and
pustules of
differing ages
Infective until all
vesicles are crusted
over (usually 6 days
after last crop)
Fifth disease
(erythema
infectiosum)
7–10 Fever,
malaise
Raised red
‘slapped
cheeks’,
diffuse
maculopapular
Transient arthralgia,
then relapsing rash;
infective before
onset of rash. Fetal
abnormality
Glandular
fever
5–14 Fever,
sore
throat,
malaise
Transient
maculopapular
(rare); itchy
drug rash with
ampicillin
(common)
Tonsillar exudate,
cervical
lymphadenopathy;
hepatosplenomegaly;
infective for many
months by close
physical contact
Measles 9–14 3 days
of cough,
cold,
conjunc-
tivitis
Red, confluent,
maculopapular;
lasts 7–11 days
Koplik’s spots;
cough predominates;
may be quite ill;
infective for 5 days
after rash appears
Rubella 14–21 None Pink,
maculopapular,
discrete; lasts
3–5 days
Occipital and pre-
auricular
lymphadenopathy;
infective until rash
disappears. Fetal
abnormality
Scarlet fever 2–5 1–2 days
of sore
throat,
fever,
vomiting
Minute, red
punctuate
papules;
last 7 days
Unwell; circumoral
pallor; ‘strawberry
tongue’; infective
until negative throat
swabs following
penicillin