Notalgia paresthetica – a borderline disease between specialities

Abstract

Notalgia paresthetica is a chronic neuropathic dysesthesia of unknown etiology characterized by localized itching of the back in the thoracic area. The condition was first described by Russian neurologist Mikhail Astwasaturow in 1934 and is usually benign. Degenerative changes in the posterior branches of the spinal nerves that occur in the T2-T6 segment, as well as some anatomical features of the muscles through which the nerve fibers penetrate, lead to compression. Paresthetic notalgia is usually observed in women after 50-55 years, localized unilaterally, and can last months or years. There are no primary lesions, only secondary changes due to chronic excoriation. An objective physical diagnosis is sufficient to stabilize the diagnosis. The treatment remains poorly effective. The nerves appear to be vulnerable to compression or traction. Partial compression or injury leads to the symptoms. The initial injury to the nerves may include back injury like: a herniated or ‘slipped’ disc, herpes zoster, sunburn, myelopathy and small fibre neuropathy. Notalgia paraesthetica often starts after a period of intense exercise leading to muscular stiffness, or a period of inactivity. A specific injury may be recalled. It is characterised by intense itch (pruritus) on the medial border of one scapula or both, ie, between the shoulder blades. This itch can be intermittent or continuous. It is unrelieved by scratching, although the scratching and rubbing may be pleasurable. The affected area may spread to both shoulder blades and more widely over the back and shoulders. In many patients, there are no visible signs. Visible changes often arise from rubbing and scratching the affected area. These include scratch marks, zones of hyperpigmentation or hypopigmentation, and eczema. There may be a changed sensation in the affected area of skin, when this is tested for with pinprick, cotton wool, or heat and cold. There may be reduced or absent sweating in the affected area. Objective: To evaluate the dermatological characteristics of notalgia paresthetica to facilitate clinical diagnosis. Material and methods We present the case of a 58-year-old patient from the countryside, who complains of intense, intermittent itching for a period of approximately 5-6 years, at the level of the posterior chest. She used various topical treatments without positive dynamics. The objective examination shows a hyperpigmented macule on the medial edge of the lower scapula, on the right, with dimensions of approximately 15x10 cm. She presented himself with a series of tests, from the family doctor, to exclude diseases of the internal organs, which can also be accompanied by itching, such as: diabetes mellitus, calculous cholecystitis, to exclude a mechanical jaundice. Chest X-ray and MRI did not reveal bone pathologies of the spine or intervertebral discs. The patient was referred to the consultation of the neurologist. The patient was referred to a neurologist. Conclusions Because these patients present with itching and local discoloration of the skin, these patients are automatically referred to the dermatologist. A more detailed analysis and an objective, correct anamnestic examination suggest the diagnosis. This case is of interest because many borderline illnesses are incorrectly diagnosed and treated.