Inverse notalgia paresthetica: a strange case of professional disease

Notalgia paresthetica: An underdiagnosed condition in primary care

ABSTRACT

Notalgia paresthetica is a perplexing diagnosis in the primary care setting. Chronic itching, paresthesia, or pain causes discomfort in patients who suffer with notalgia paresthetica and it is thought to be a common but underdiagnosed condition. Recognition of this dermatologic condition can lead to reassurance and relief for affected patients.

The etiology of notalgia paresthetica: a descriptive study of 117 patients

BACKGROUND

Notalgia paresthetica (NP) is a neuropathic itching condition unilaterally localized in the midscapular area. It is a common but an underdiagnosed disease, and only a few studies investigating NP etiology with a limited number of patients have been reported in the literature.

OBJECTIVE

We aimed to evaluate the demographic, clinical, histopathological, neurological, and radiological findings of NP patients and investigate correlations between them and symptoms of NP to elucidate the etiology of NP.

METHODS

One hundred and seventeen consecutive patients diagnosed with NP were included and assessed in a multidisciplinary and prospective manner. We recorded demographic and clinical data and obtained a skin biopsy from the pruritic or hyperpigmented region. Pruritus severity was assessed by visual analogue scale (VAS). All patients were evaluated neurologically with magnetic resonance imaging.

RESULTS

The mean age of the patients was 47.08 ± 12.28 years. The disease was more common in females (87.2%). Statistical analysis revealed that VAS scores were independent of the age, gender, and skin type of the patient. We found no significant difference in VAS scores between NP patients with or without comorbidities. Vertebral pathologies detected by MRI and amyloid deposition revealed in histopathology were not among the main factors affecting VAS scores.

STUDY LIMITATION

Since consecutive patients enrolled into the study, we could not include equal number of male and female patients.

CONCLUSION

We found no correlation between symptom severity and findings from neurological and histopathological evaluations. Further microneurological studies should be carried out to elucidate the etiology of NP.

Loco-regional immune default: The immunocompromised district in human and comparative dermatology

Lately, the innovative concept of an immunocompromised cutaneous district (ICD) has been introduced to explain why a previously injured cutaneous site may become in time a privileged location for the onset of opportunistic infections, tumors, and immune reactions. The injuring events capable of rendering a skin region a potential ICD are various, numerous, and most of the time identifiable by means of a careful clinical history. The reason that only a small minority of injured skin areas actually becomes ICDs, with subsequent opportunistic localization of a second and unrelated skin disorder, is presently unknown. The ICD is a conceptual entity that is not limited to human dermatology. It can also apply to veterinary medicine. Development of sarcomas at the injection site in cats after routine vaccination and, occasionally, administration of pharmaceutical products, as well as insertion of any foreign body, is a repeatedly documented event. Antigen load, persistent inflammation, and fibroblastic proliferation are thought to be important factors predisposing to the onset of fibrosarcoma in cats. Recently, it has been hypothesized that a local immunosuppression caused by inhalant glucocorticoids may have favored the development of regional demodicosis in cats. In our opinion, injection-site sarcomas and feline localized demodicosis can be considered examples of veterinary ICDs.

Chronic pruritus in the elderly: pathophysiology, diagnosis and management

Chronic itch in the elderly is a common problem, with a significant impact on quality of life and sleep in elderly patients. Chronic itch may be attributable to several causes, including dry skin, immunosenescence and neural degeneration. Itch may also be caused by skin diseases, such as seborrhoeic dermatitis and stasis dermatitis; systemic conditions, such as end-stage renal disease and diabetes; and psychogenic conditions, such as depression and anxiety. The use of polypharmacy may also cause itch, with or without a rash. Specifically, thiazides and calcium channel blockers have been known to cause itch in elderly patients. Management should be tailored according to the underlying dermatological or systemic aetiology of itch. Topical treatment is the mainstay of therapy, providing special emphasis on skin hydration and barrier repair. In addition, topical and oral medications that target the nervous system and reduce neuronal hypersensitization, such as gabapentin and selective antidepressants, have a role in treating patients with severe chronic itch. Furthermore, management must account for changes in metabolism and pharmacokinetics of drugs in the aging population in order to prevent the occurrence of adverse effects.

Categorization of and comments on isomorphic and isotopic skin reactions

Locus minoris resistentiae (lmr) can be defined as a site of the body that offers lesser resistance than the rest of the body to the onset of disease. The well-known Köbner phenomenon is itself a clear example of lmr in dermatology. The new term locus maioris resistentiae (LMR), a site of the body that offers greater resistance than the rest of the body to the onset of disease, defines the opposite condition. Renbök phenomenon (reverse Köbner's isomorphic response) typically represents an example of LMR.