Atypical pityriasis rosea or psoriasis guttata? Early examination is the key to a correct diagnosis.

Pityriasis rosea is a self-limited, mild, inflammatory skin disease characterized by scaly lesions, possibly due to an unidentified infectious agent. It may occur at any age, but is seen most frequently in young adults. This paper reports a patient who presented with a skin condition which was initially diagnosed as pityriasis rosea; however, due to the persistence and change in appearance of the lesions, the diagnosis was later altered to psoriasis guttata. Changes in pityriasis rosea lesions over the course of the disease may make a correct diagnosis difficult, unless the patient is seen during the early stages of lesion formation. The final diagnosis in this case was of the rare variant known as pityriasis rosea irritata. This case highlights the importance of an excellent patient history in order to correctly diagnose the disease.