To the Editor I read with great interest the Teachable Moment “Overevaluating Chronic Pruritus.” Smucker et al1 attribute a case of chronic itch in a woman in her 50s to psychogenic causes based on the presence and distribution of excoriations in the absence of a primary rash. They also cite observations that the patient failed a 2-week course of a medium-potency topical steroid, had more intense bouts of itch at night, and had comorbid depression to support this diagnosis. The chief argument by Smucker et al is that the evaluation of chronic itch in this patient, as in many cases, does not require an exhaustive systemic workup, which is a valid and important lesson. However, it is equally critical to consider that this patient may have neurogenic or neuropathic pruritus, or even a subclinical inflammatory dermatosis where itch precedes overt signs of inflammation,2 as can be observed with some drug or environmental hypersensitivity reactions, dermatitis herpetiformis, or inflammatory bullous disorders.3- 5 Each of these conditions may present with chronic itch with or without a clinically apparent rash. In such cases, histologic evidence of inflammation or of nerve alteration may be present despite the absence of an obvious rash.
Elmariah SB. Careful Considerations Concerning Psychogenic Itch. JAMA Intern Med. 2015;175(11):1861. doi:10.1001/jamainternmed.2015.4677