Platelet-rich plasma for the treatment of alopecia: a systematic review and meta-analysis

Platelet rich plasma use for treatment of acne scars: an overview of systematic reviews

BACKGROUND

A reappraisal of the conclusions of systematic reviews (SRs) and meta-analyses validity related to Platelet-rich plasma (PRP), alone or in combination with other treatments, compared to regimens PRP-free for the treatment of acne scars.

MATERIALS AND METHODS

An overview of SRs. The methodological quality of the reviews was assessed using AMSTAR-2 checklist; quality of the evidence of primary studies was appraised following the GRADE approach.

RESULTS

Fifteen SRs were included in this overview. Data were from 124 overlapping reports, based on 34 individual primary studies (10 parallel arm randomized trials, 21 split-face studies, and 3 uncontrolled studies). Most of the studies evaluated combination of PRP with microneedling or with laser therapy compared to microneedling or laser therapy without PRP. Clinical improvement (reported as degree of improvement or improvement score) and patient's satisfaction rate were significantly higher in PRP recipients compared to controls. Crusting time and duration of erythema were significantly shorter in PRP recipients compared to controls. Most of the reviews considered in this overview can be considered of low methodological quality due to the fact that several critical methodological requirements of AMSTAR-2 checklist were unmet or partially met; only 6 of the 15 reviews incorporated study quality in their conclusions, and no GRADE assessment was performed for the reported outcomes in any of the SRs. With the GRADE approach, the quality of the evidence for the outcomes analysed ranged from very low to low due to risk of bias in the primary studies, inconsistency between the studies, and imprecision.

DISCUSSION

The low or very low certainty of evidence does not support clear clinical decision about the PRP use in combination with microneedling or laser therapy for the treatment of acne scars. Further well-designed studies are required to improve the evidence base for PRP combination therapy for acne scars.

The role of platelet-rich plasma in androgenetic alopecia: A systematic review

BACKGROUND

Androgenetic alopecia (AGA), also referred to as male or female pattern hair loss, is the commonest cause of chronic hair loss and affects up to 80% of men by the age of 70. Despite a high prevalence, there are few approved therapies, which show minimal efficacy.

OBJECTIVES

This systematic review aims to evaluate the efficacy of platelet-rich plasma (PrP) in the treatment of AGA in male patients.

METHODS

MEDLINE, EMBASE, Cochrane (CENTRAL), CINAHL, clinicaltrials.gov, Google Scholar and the Science Citation Index database were searched to identify eligible studies. All randomized controlled trials (RCTs) and prospective cohort studies related to PrP use in AGA were included. Primary outcomes included changes in hair density and hair count. Methodological quality was assessed using bias assessment tools.

RESULTS

Eight RCTs and one cohort study were included in the review with a total of 291 participants. Six studies reported a statistically significant increase in hair density in the PrP group versus the control. Five studies reported a statistically significant increase in hair count with PrP. Seven studies showed moderate risk and two showed low risk of bias.

CONCLUSION

In a methodologically robust review on the effectiveness of PrP on male AGA, PrP demonstrated some potential to be used therapeutically. However, the low quality of evidence, moderate risk of bias, and high heterogeneity of included studies limit inferences and call for more robust designs to investigate this further.

How Our Microbiome Influences the Pathogenesis of Alopecia Areata

Alopecia areata is a multifactorial autoimmune-based disease with a complex pathogenesis. As in all autoimmune diseases, genetic predisposition is key. The collapse of the immune privilege of the hair follicle leading to scalp loss is a major pathogenic event in alopecia areata. The microbiota considered a bacterial ecosystem located in a specific area of the human body could somehow influence the pathogenesis of alopecia areata, as it occurs in other autoimmune diseases. Moreover, the Next Generation Sequencing of the 16S rRNA bacterial gene and the metagenomic methodology have provided an excellent characterization of the microbiota. The aim of this narrative review is to examine the published literature on the cutaneous and intestinal microbiota in alopecia areata to be able to establish a pathogenic link. In this review, we summarize the influence of the microbiota on the development of alopecia areata. We first introduce the general pathogenic mechanisms that cause alopecia areata to understand the influence that the microbiota may exert and then we summarize the studies that have been carried out on what type of gut and skin microbiota is found in patients with this disease.