Distinguishing Features: Linear Rashing is Not Always Koebnerization

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Nneamaka Ezekwe
Thy Huynh
Robert Brodell


Dermatology, Cutaneous Sarcoidosis, Psoriasis, Scar Sarcoidosis, Immunocompromised District, Koebner, Koebner Phenomenon


Cutaneous sarcoidosis and psoriasis are dermatologic conditions that can have a similar clinical appearance.  Psoriasiform sarcoidosis shows thick white or silvery scaling reminiscent of psoriasis and both conditions can be linear.  Psoriasis is associated with linear scaled patches that are induced by mechanical trauma (Koebner Phenomenon).  Linear lesions in cutaneous sarcoidosis are not a result of koebnerization, rather cutaneous granulomas appear in well-healed scars decades after the trauma within what can be termed an immunocompromised district.  This paper will focus on the features that distinguish psoriasis and cutaneous sarcoidosis, since prompt diagnosis leads to appropriately targeted treatment.


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