Notalgia Paresthetica of the Back Successfully Controlled by Pregabalin / 대한피부과학회지

Notalgia paresthetica (NP) is a chronic localized itch, affecting mainly the inter-scapular area particularly between the T2-T6 dermatomes. Occasionally it has a more widespread distribution and involves the shoulders, back, and upper chest. There are no specific cutaneous signs, apart from those attributed to scratching and rubbing. Various etiologies have been reported, but the cause of NP is not established. The current hypothesis regarding its etiology postulates that a neuropathic itch develops due to nerve entrapment of the posterior rami of spinal nerve arising at T2-T6. Another recent documented case showed an increase in the number of intradermal nerves by neural immunochistochemistry staining of S-100 protein, protein gene product 9.5 (PGP 9.5). Herein, we experienced an uncommon case of NP of the back and tried to clarify pathogenesis by using quantitative sensory testing, such as neurometer and Von-Frey filaments. Also, we performed neural immunochemistry to confirm an increase in nerve fibers at the site of the lesion.

Considerable Variability in the Efficacy of 8% Capsaicin Topical Patches in the Treatment of Chronic Pruritus in 3 Patients with Notalgia Paresthetica

Notalgia paresthetica (NP) is a focal neuropathic itch condition manifesting in intense chronic or recurrent episodic itch in a hyperpigmented, macular, uni- or bilateral skin area located below and/or medially to the scapulae. Achieving satisfactory relieve in NP patients is challenging. In this case-series three female NP patients were treated with 8% capsaicin patches following a spatial quantification of their alloknetic area with a von Frey filament. The use of a von Frey filament in order to delimit the precise area of itch sensitization and thus patch application, proved clinically feasible. Although 8% topical capsaicin relieved itch in all three patients, the duration of the effectiveness varied greatly from only 3 days to >2 months. The treatment was well tolerated in the patients and there appear to be no significant hindrances to applying this treatment with NP as an indication, although it may only exhibit satisfactory effectiveness in certain patients. Placebo-controlled double-blinded trials are needed to confirm the effectiveness of the treatment and assess predictive parameters of the treatment outcome.

A Case of Intractable Postherpetic Itch / 대한피부과학회지

Herpes zoster is an infective skin disease that is encountered commonly in dermatologic field. The best known complication of herpes zoster is postherpetic neuralgia (PHN). Also, many patients with herpes zoster experience neuropathic itch with or without pain. Those postherpetic itches (PHI) are rare, but some patients injure themselves by scratching skin with severe itching sensation, and with the loss of the protective sensation. So, PHI should be considered when evaluating a patient after an occurance of herpes zoster. Gabapentin has been successfully used to treat PHI in some cases. We report a case of postherpetic itch that has been successfully treated with gabapentin, as an unusual clinical presentation.