A pilot study to assess the efficacy of photodynamic therapy for Japanese patients with actinic keratosis in relation to lesion size and histological severity

On the Possibility of Using 5-Aminolevulinic Acid in the Light-Induced Destruction of Microorganisms

Antimicrobial photodynamic inactivation (aPDI) is a method that specifically kills target cells by combining a photosensitizer and irradiation with light at the appropriate wavelength. The natural amino acid, 5-aminolevulinic acid (5-ALA), is the precursor of endogenous porphyrins in the heme biosynthesis pathway. This review summarizes the recent progress in understanding the biosynthetic pathways and regulatory mechanisms of 5-ALA synthesis in biological hosts. The effectiveness of 5-ALA-aPDI in destroying various groups of pathogens (viruses, fungi, yeasts, parasites) was presented, but greater attention was focused on the antibacterial activity of this technique. Finally, the clinical applications of 5-ALA in therapies using 5-ALA and visible light (treatment of ulcers and disinfection of dental canals) were described.

Photodynamic Therapy, Probiotics, Acetic Acid, and Essential Oil in the Treatment of Chronic Wounds Infected with Pseudomonas aeruginosa

As a prevalent medical problem that burdens millions of patients across the world, chronic wounds pose a challenge to the healthcare system. These wounds, often existing as a comorbidity, are vulnerable to infections. Consequently, infections hinder the healing process and complicate clinical management and treatment. While antibiotic drugs remain a popular treatment for infected chronic wounds, the recent rise of antibiotic-resistant strains has hastened the need for alternative treatments. Future impacts of chronic wounds are likely to increase with aging populations and growing obesity rates. With the need for more effective novel treatments, promising research into various wound therapies has seen an increased demand. This review summarizes photodynamic therapy, probiotics, acetic acid, and essential oil studies as developing antibiotic-free treatments for chronic wounds infected with Pseudomonas aeruginosa. Clinicians may find this review informative by gaining a better understanding of the state of current research into various antibiotic-free treatments. Furthermore. this review provides clinical significance, as clinicians may seek to implement photodynamic therapy, probiotics, acetic acid, or essential oils into their own practice.

Open study of photodynamic therapy for skin ulcers infected with MRSA and Pseudomonas aeruginosa

BACKGROUND

Drug-resistant bacterial infections are a global problem. Novel treatment methods that simultaneously control infection and promote wound healing without leading to new resistant bacteria are needed. Photodynamic therapy (PDT) is a useful antibiotic-free treatment approach. Our previous studies have shown that PDT for skin ulcers infected with methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa (PA) can achieve infection control and promoting wound healing in vitro and in vivo murine model. Here, we investigated the safety and effectiveness of PDT with 5-aminolevulinic acid (ALA-PDT) for human skin ulcers infected with MRSA and PA.

METHODS

ALA-PDT with macrogol ointment containing 0.5% ALA-HCl and 0.005% EDTA-2Na (wavelength 410 nm, 10 J/cm²) was performed on consecutive days in patients aged ≥20 years who had skin ulcers infected with MRSA and PA.

RESULTS

Six of our seven patients showed a clear tendency for ulcer area reduction to ≤60% of that measured at baseline. ALA-PDT was judged to be completely safe in all patients; only one patient had an increase in bacterial count.

CONCLUSIONS

ALA-PDT is safe and effective for MRSA and PA infected skin ulcers to control and heal wound.

In vivo reflectance confocal microscopy for monitoring actinic keratosis treated with 5-aminolevulinic acid photodynamic therapy

BACKGROUND

Actinic keratosis (AK) occurs frequently in sun-exposed skin while its diagnosis and treatment were still in exploration.

MATERIALS AND METHODS

Thirty two patients with facial AK lesions were selected and examined with reflective confocal microscopy (RCM) firstly, followed by biopsy at the same site. RCM was used to observe AK lesions before 5-aminolevulinic acid photodynamic therapy (ALA-PDT) treatment, after the first treatment, after 4 treatments, and at 1 and 6 months follow-up. Retrospective analysis of RCM images was performed.

RESULTS

Thirty two AK cases showed initial RCM microscopic features including disorderly arranged epidermal cells (100%), atypical keratinocytes (100%), and blurry border between the epidermis and dermis (100%). 4 patients quitted trail. After treatments, 24 cases showed basically regular arrangement of epidermal cells, absent atypical keratinocytes, and clear border between epidermis and dermis, while 4 cases improved little. At 1 and 6 months follow-up, 23 cases remained relapse-free while 1 case developed recurrent symptoms. Effective rate of 4 ALA-PDT treatments for AK was 100%; recurrence and cure rates were 4.2% and 82.1%, respectively.

CONCLUSION

ALA-PDT is effective to treat AK, while RCM can be recommended for in vivo evaluating and monitoring the effect of ALA-PDT on AK.

Photodynamic therapy activated by intense pulsed light in the treatment of actinic keratosis

BACKGROUND

Actinic keratosis (AK), a hyperkeratotic lesion induced by solar exposure, is the precancerous lesion that most frequently develops into squamous cell carcinoma. Cryotherapy, topical fluorouracil 5, topical diclofenac 3% gel and, more recently, ingenol mebutate are used in addition to surgery. However, these treatments have varying degrees of effectiveness and are not always tolerated due to side effects. In recent years, photodynamic therapy (PDT), has asserted itself as a new effective and safe method for the treatment of actinic keratoses with almost no side effects. The aim of this study is to verify whether a third treatment may now be added to the "Conventional -PDT" and "Daylight-PDT": PhotoDynamic Therapy activated by Intense Pulsed Light (IPL-PDT).

METHODS

Thirty-one patients, 24 males and 7 females, in most cases elderly, were included in the trial. As in the previous methods, also in IPL-PDT, 5-methylaminolevulinic acid (MAL) was applied topically for a period of 3 hours. Thereafter, the occlusive dressing and the topical cream, were removed and the neoformation was irradiated with IPL, with a 640 nm filter with variable power. Irradiation was performed in single or multiple sessions, depending on the type of keratosis, to completely cover the lesion and the apparently healthy surrounding areas, i.e. the cancerization field.

RESULTS

Results were evaluated 3, 6 and 9 months after treatment. Treatment achieved a 95% complete clearance rate, with a 5% partial relapse, 9 months after the last treatment.

CONCLUSIONS

The above method is a valid alternative to methods already in use. The results obtained demonstrate the efficacy and tolerability of the treatment described which, due to its versatility and speed of use, is preferable to the methods used so far.

Comparative Study of Photodynamic Therapy with Topical Methyl Aminolevulinate versus 5-Aminolevulinic Acid for Facial Actinic Keratosis with Long-Term Follow-Up

Background

Few studies have compared the efficacy, cosmetic outcomes, and adverse events between 5-aminolevulinic acid photodynamic therapy (ALA-PDT) and methyl aminolevulinate-PDT (MAL-PDT) for actinic keratoses (AKs) in Asian ethnic populations with dark-skin.

Objective

We retrospectively compared the long-term efficacy, recurrence rates, cosmetic outcomes, and safety of ALA-PDT versus MAL-PDT for facial AKs in Koreans.

Methods

A total of 222 facial AKs in 58 patients were included in this study. A total of 153 lesions (29 patients) were treated with 5-ALA, and 69 lesions (29 patients) with MAL. ALA and MAL creams were applied for 6 hours and 3 hours, respectively; the lesions were then illuminated with a halogen lamp at 150 J/cm² for ALA-PDT and a diode lamp at 37 J/cm² for MAL-PDT.

Results

The complete response rates of ALA-PDT and MAL-PDT were 56.9% and 50.7%, respectively, with no significant difference at 12 months after treatment. No significant difference in recurrence rates was observed between the 2 PDT modalities at either 6 or 12 months after treatment. There was no significant difference in the cosmetic outcomes between the 2 treatment modalities at 12 months after PDT. However, ALA-PDT caused significantly more painful than MAL-PDT (p=0.005). The adverse events were mild to moderate, transient, and self-limiting for both modalities.

Conclusion

MAL-PDT was similar to ALA-PDT in terms of long-term efficacy, recurrence rates, cosmetic outcomes, and adverse events; however, it was a significantly less painful procedure than ALA-PDT in our study.

Single vs. fractionated photodynamic therapy for face and scalp actinic keratoses: a randomized, intraindividual comparison trial with 12-month follow-up

OBJECTIVE

To compare the efficacy and tolerability of a single ALA-PDT illumination scheme with that of a fractionated ALA-PDT illumination scheme in face and scalp actinic keratoses (AKs).

METHODS

Eligible patients received either a single ALA-PDT illumination or a fractionated illumination scheme randomly allocated to alternate sides of face/scalp. The side allocated to a single illumination received 75 J/cm(2). This side received 2 sessions performed 7 days apart. Lesions on the fractionated illumination scheme side received 20 and 80 J/cm(2), 4 and 6 hours after a single ALA application. Patients were evaluated at baseline, at 3 and 12 months after treatment. Efficacy end point included the individual AK lesion clearance rate.

RESULTS

Thirty three patients with 266 lesions were enrolled in the study. Three months after treatment the overall lesion complete response rate was 89.05% for the single scheme and 96.12% for the fractionation scheme while at the 12-months follow-up response rate decreased to 85.4% for the single illumination and to 93.79% for the fractionated illumination group. Looking at lesion response based on lesion grade fractionated photodynamic therapy (PDT) resulted in larger rates of cured grade I as well as grade II lesions. Recorded adverse events were transient and did not demand additional therapy.

CONCLUSIONS

Our results demonstrate that higher responses are achieved with fractionated PDT compared with single illumination PDT. The study data indicate that fewer treatment sessions may be needed with fractionated PDT increasing that way the comfort of the patient regarding number of visits, treatment cost and treatment-related downtime.

5-Aminolevulinic acid-mediated photodynamic therapy to superficial malignant skin tumors using Super Lizer

Photodynamic therapy (PDT) using topically applied 5-aminolevulinic acid (ALA) has become a generally accepted treatment modality for superficial malignant skin tumors. However, the costly excimer-dye laser, diode laser and light-emitting diode (LED) frequently used to administrate PDT are impractical to use in most dermatology clinics. This study evaluated the effectiveness of ALA-mediated PDT using a Super Lizer (Tokyo Iken, Tokyo, Japan) equipped with band-pass filters in 38 patients with superficial malignant skin tumors (33 cases of actinic keratosis and five cases of Bowen's disease). Twenty-one cases (18 cases of actinic keratosis and three cases of Bowen's disease) were successfully treated, and the other 17 cases (15 cases of actinic keratosis and two cases of Bowen's disease) showed partial remission after single or repeated administration of PDT. PDT repeated three times at weekly intervals was more effective against actinic keratosis than randomly repeated procedures. The Super Lizer is easy to handle and move, and is less expensive than other known machinery and is useful for PDT in dermatology, especially under the protocol of three times at weekly intervals for the treatment of actinic keratosis.