Parakeratosis pustulosa is a cutaneous condition which is exclusively seen in children, usually involving one finger, most commonly the thumb or index finger, with the affected nail showing subungual hyperkeratosis and

onycholysis Onycholysis is a common medical condition characterized by the painless detachment of the nail from the nail bed, usually starting at the tip and/or sides. On the hands, it occurs particularly on the ring finger but can occur on any of the fingern ...

.Freedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. . The cause of parakeratosis pustulosa is unknown however there have been several diseases linked to it and it does not seem to be genetic. Parakeratosis pustulosa is diagnosed based on clinical characteristics and the exclusion of other conditions.

Signs and symptoms

Parakeratosis pustulosa is most commonly seen in children as an eczematoid eruption near the free margin of the nail that extends to the dorsal nail fold. Under the free margin of the nail,

hyperkeratosis Hyperkeratosis is thickening of the stratum corneum (the outermost layer of the epidermis, or skin), often associated with the presence of an abnormal quantity of keratin,Kumar, Vinay; Fausto, Nelso; Abbas, Abul (2004) ''Robbins & Cotran Pathologi ...

causes the nail plate to pull up and results in a deformity that resembles a gaping toecap that is separated from the sole at the seam. Pitting and sporadic cross-ridging of the nail plate are more common in finger nails than toe nails.

Causes

Its cause is yet unknown. It appears that parakeratosis pustulosa is not inherited if it is not present in siblings or other family members.

Psoriasis Psoriasis is a long-lasting, noncontagious autoimmune disease characterized by raised areas of abnormal skin. These areas are red, pink, or purple, dry, itchy, and scaly. Psoriasis varies in severity from small, localized patches to complete ...

onychomycosis Onychomycosis, also known as tinea unguium, is a fungal infection of the nail. Symptoms may include white or yellow nail discoloration, thickening of the nail, and separation of the nail from the nail bed. Toenails or fingernails may be affected, ...

, and chronic dry fissured eczematoid

dermatitis Dermatitis is inflammation of the skin, typically characterized by itchiness, redness and a rash. In cases of short duration, there may be small blisters, while in long-term cases the skin may become thickened. The area of skin involved can ...

have all been frequently linked to it.

Diagnosis

The diagnosis of parakeratosis pustulosa is made based on clinical features and the exclusion of other disorders.

Treatment

There is no suggested specific therapy. Topical emollients are still the advised course of treatment, even though

topical corticosteroids Topical steroids are the topical forms of corticosteroids. Topical steroids are the most commonly prescribed topical medications for the treatment of rash, eczema, and dermatitis. Topical steroids have anti-inflammatory properties and are classifie ...

have been utilized in the majority of reports. Topical

tretinoin Tretinoin, also known as all-''trans'' retinoic acid (ATRA), is a medication used for the treatment of acne and acute promyelocytic leukemia. For acne, it is applied to the skin as a cream, gel or ointment. For leukemia, it is taken by mouth ...

therapy might not be necessary for many people.

Epidemiology

The exact prevalence of parakeratosis pustulosa is unknown. It is more common in girls and occurs only in children.

References

External links

DermNet

VisualDx
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