Immune Status

The immune status of the patient can alter the expression of the disease.

Consider zoster (shingles) infection. In immunocompromised patients, such as a patient with AIDS, the infection can present with erosions, ulcers, eschars, or even papules rather than the typical vesicles seen in the immunocompetent patient.

With scabies, an immunocompromised patient may develop a more severe case, called crusted scabies, than an immunocompetent patient.

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  Grouped umbilicated vesicles on an erythematous base in a dermatomal distribution is the classic presentation of zoster.

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  In the immunocompromised patient, zoster can be extremely inflammatory, with skin ulcers following the vesicles.

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  Classic scaly and smooth papules of scabies in the web spaces and on the fingers of an immunocompetent patient.

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  Crusted scabies with thickly heaped-up "dirty white" scales and fissuring at the first finger web in this immunocompromised patient.