Morphometry of dermal nerve fibers in human skin.

OBJECTIVE: We aimed to assess the innervation density of dermal nerves in human skin biopsies by bright-field immunohistochemistry. METHODS: The size of dermal area where nerve length was quantified was validated in 30 skin biopsy sections (5 controls and 5 patients with small-fiber neuropathy [SFN]). It was obtained dividing an area of 200-µm depth from the dermal-epidermal junction into 4 equal portions. The length of dermal nerves (DNFL) was measured into 150 sections (25 controls and 25 patients with SFN) and values per millimeter of epidermis (DNFL/mm) and dermal area (DNFL/mm2) were obtained. Age- and gender-matched normative values of intraepidermal nerve fiber (IENF) density were used as gold standard to calculate the performance of dermal nerve morphometry. RESULTS: Patients showed significantly lower DNFL (1.96 mm ± 0.96 SD), DNFL/mm (0.65 ± 0.29 SD), and DNFL/mm2 (3.75 ± 1.7 SD) than controls (DNFL 3.52 mm ± 1.31 SD, 5th percentile 2.05; DNFL/mm 1.25 ± 0.39, 5th percentile 0.71; DNFL/mm2 7.07 ± 2.41 SD, 5th percentile 3.95). Sensitivity, specificity, and percentage of individuals correctly classified were 75.8%, 73.9%, and 74.8% for DNFL, 75%, 80%, and 77.7% for DNFL/mm, and 75.8%, 80.2%, and 78.1% for DNFL/mm2. Receiver operator characteristic area analysis confirmed the excellent discrimination (0.8-0.9) between patients and controls. Dermal nerve morphometry significantly correlated with IENF density. Spearman rank correlation demonstrated good agreement for interobserver analysis (0.87-0.89), and between DNFL and IENF densities (0.71-0.73; p < 0.0001). CONCLUSIONS: We provided a reliable method to quantify the innervation density of dermal nerves that might improve the diagnostic yield of skin biopsy.

Intraepidermal nerve fiber density and its application in sarcoidosis.

BACKGROUND: Intraepidermal nerve fiber density (IENFD) is considered a good diagnostic tool for small fiber neuropathy (SFN). OBJECTIVES: To assess stratified normative values for IENFD and determine the reliability and validity of IENFD in sarcoidosis. METHODS: IENFD was assessed in 188 healthy volunteers and 72 patients with sarcoidosis (n = 58 with SFN symptoms, n = 14 without SFN symptoms). Healthy controls were stratified (for age and sex), resulting in 6 age groups (20-29, 30-39, ... up to > or = 70 years) containing at least 15 men and 15 women. A skin biopsy was taken in each participant 10 cm above the lateral malleolus and analyzed in accordance with the international guidelines using bright-field microscopy. Interobserver/intraobserver reliability of IENFD was examined. In the patients, a symptoms inventory questionnaire (SIQ; assessing SFN symptoms) and the Vickrey Peripheral Neuropathy Quality-of-Life Instrument-97 (PNQoL-97) were assessed to examine the discriminative ability of normative IENFD values. RESULTS: There was a significant age-dependent decrease of IENFD values in healthy controls, with lower densities in men compared with women. Good interobserver/intraobserver reliability scores were obtained (kappa values > or = 0.90). A total of 21 patients with sarcoidosis had a reduced IENFD score (< 5th percentile; 19 [32.8%] in patients with SFN symptoms, 2 [14.3%] in patients without SFN symptoms). The validity of the normative IENFD values was demonstrated by distinguishing between the SIQ scores and various PNQoL-97 values for the different patient groups. CONCLUSION: This study provides clinically applicable distal intraepidermal nerve fiber density normative values, showing age- and sex-related differences.

Neumomediastino espontáneo asociado al consumo de drogas inhalantes / Spontaneous pneumomediastinum as a complication of inhalant drug use

El neumomediastino es una entidad descripta por Hamman en 1939 y cuya patogenia fue establecida por Macklin en 1944(1). Se define por la presencia de aire en el mediastino y el carácter de espontáneo se lo otorga la ausencia de vinculación con otras patologías asociadas. Es una enfermedad benigna, infrecuente, autolimitada y que puede asociarse a neumotórax. Este trabajo presenta dos casos de neumomediastino espontáneo, sin neumotórax, en los cuales se destaca la concomitancia de inhalación de cocaína y pasta base de cocaína.

Validation of AIDA Cefalee, a computer-assisted diagnosis database for the management of headache patients.

AIDA Cefalee is a database for the management of headache patients developed on behalf of the Italian Neurological Association for Headache Research (ANIRCEF). The system integrates a diagnostic expert system able to suggest the correct ICHD-II diagnosis once all clinical characteristics of a patient's headache have been collected. The software has undergone a multicentre validation study to assess: its diagnostic accuracy; the impact of using the software on visit duration; the userfriendliness degree of the software interface; and patients' acceptability of computer-assisted interview. Five Italian headache centres participated in the study. The results of this study validate AIDA Cefalee as a reliable diagnostic tool for primary headaches that can improve diagnostic accuracy with respect to the standard clinical method without increasing the time length of visits even when used by operators with basic computer experience.