The effect of autologous activated platelet rich plasma (AA-PRP) injection on pattern hair loss: clinical and histomorphometric evaluation.

To investigate the safety and clinical efficacy of AA-PRP injections for pattern hair loss. AA-PRP, prepared from a small volume of blood, was injected on half of the selected patients' scalps with pattern hair loss. The other half was treated with placebo. Three treatments were given for each patient, with intervals of 1 month. The endpoints were hair re-growth, hair dystrophy as measured by dermoscopy, burning or itching sensation, and cell proliferation as measured by Ki-67 evaluation. At the end of the 3 cycles of treatment, the patients presented clinical improvement in the mean number of hairs, with a mean increase of 18.0 hairs in the target area, and a mean increase in total hair density of 27.7 ( number of hairs/cm(2)) compared with baseline values. Microscopic evaluation showed the increase of epidermis thickness and of the number of hair follicles two weeks after the last AA-PRP treatment compared to baseline value (P < 0.05). We also observed an increase of Ki67(+) keratinocytes of epidermis and of hair follicular bulge cells and a slight increase of small blood vessels around hair follicles in the treated skin compared to baseline (P < 0.05).

Platelet-rich plasma and blood components for non-transfusion use: technical and medicolegal aspects.

There are a large number of publications describing the use of platelet-rich plasma (PRP) in multiple fields of application. These illustrate a large number of therapeutic elements with different and specific actions within 'platelet gel' (this term is used in the current regulations to define this product). This term, however, lacks specificity and, depending on the method used in its production is variable both in its blood composition and in platelet concentration, and several publications consider better and easier methods of platelet gel production, which may or may not lead to greater standardization in the product. The authors illustrate the general aspects of PRP and other blood components for non-transfusion use, briefly touching on the history and different fields of application and the rational of for its use. Given the increased use of such preparations, the authors describe critically the regulations in force in Europe and propose a new regulatory framework aimed to simplify and facilitate the use of such material as a therapeutic agent within medicine.