A. Deep seated.
C. Affects palm & sole.
D. Slow evolution.
The condition shown in the picture above represents chicken pox.
- the incubation period is from 14 up to 21 days
- chicken pox is infectious from a few days before the onset of rash develops and not more than six days after first lesions appear.
- this period may be prolonged in immunocompromised patients.
- chickenpox is very infectious – cases on a ward ought to be isolated to prevent cross infection
- the rash begins as macular lesions which develop into papular, or vesicular lesions (filled with fluid) and later becomes pustular
- chickenpox rash has a centripetal distribution – mostly on the face and trunk and sparsely on the limbs
- there is erythema around the lesions and they are intensely itchy
- usually the rash peaks at around 48 hours in immunocompetent people
- vesicles dry and crust over, and sometimes scar if scratched to excess
- oropharynx and genital tract mucous membranes may be involved as well
- new lesions can emerge for up to 5 days.
- a haemorrhagic rash may occur in immuno-suppressed patients
In children under 10 years, the disease is usually mild and self limiting, but a more severe infection can be seen in
- adults – especially in pregnant women and in smokers since they are at an increased risk of developing fulminanting varicella pneumonia
- neonates and immunosupressed individuals – there is an increased risk of developing disseminated or haemorrhagic varicella.
Signs of severe infections include:
- respiratory symptoms (clinical respiratory signs are often absent).
- densely cropping vesicles
- haemorrhagic rash
- bleeding from gums, haemoptysis, GI bleeding
- any neurological changes – cerebellar signs, encephalopathy
- persisting fever with new vesicles >6 days after onset.