A new approach to the treatment of nontuberculous mycobacterium skin infections caused by iatrogenic manipulation: Photodynamic therapy combined with antibiotics: A pilot study

Fire needle combined with photodynamic therapy for cutaneous infectious granulomatosis caused by mycobacterium chelonae: A case report

Mycobacterium chelonae is a non-tuberculous mycobacteria, which can cause skin infectious granuloma through cosmetic injection. This disease's treatment requires a combination of sensitive antibiotics and a lengthy treatment cycle. Photodynamic therapy is still effective for patients who are unwilling to take antibiotics orally. In this case, we successfully used fire needle combined with photodynamic therapy to treat skin infectious granulomatosis caused by Mycobacterium chelonei, and achieved satisfactory results. We used fire needle to pretreat cysts and nodules, which improved the diffusion and absorption of locally applied photosensitizers and enhanced the efficacy of photodynamic therapy. However, additional clinical research is necessary to determine the efficacy and safety of fire needle combined with photodynamic therapy for cutaneous infectious granulomatosis.

Acquiring of photosensitivity by Mycobacterium tuberculosis in vitro and inside infected macrophages is associated with accumulation of endogenous Zn-porphyrins

Mycobacterium tuberculosis (Mtb) is able to transition into a dormant state, causing the latent state of tuberculosis. Dormant mycobacteria acquire resistance to all known antibacterial drugs and can survive in the human body for decades before becoming active. In the dormant forms of M. tuberculosis, the synthesis of porphyrins and its Zn-complexes significantly increased when 5-aminolevulinic acid (ALA) was added to the growth medium. Transcriptome analysis revealed an activation of 8 genes involved in the metabolism of tetrapyrroles during the Mtb transition into a dormant state, which may lead to the observed accumulation of free porphyrins. Dormant Mtb viability was reduced by more than 99.99% under illumination for 30 min (300 J/cm2) with 565 nm light that correspond for Zn-porphyrin and coproporphyrin absorptions. We did not observe any PDI effect in vitro using active bacteria grown without ALA. However, after accumulation of active cells in lung macrophages and their persistence within macrophages for several days in the presence of ALA, a significant sensitivity of active Mtb cells (ca. 99.99%) to light exposure was developed. These findings create a perspective for the treatment of latent and multidrug-resistant tuberculosis by the eradication of the pathogen in order to prevent recurrence of this disease.

ALA-PDT shortens the course of antibiotic therapy for skin infection caused by Mycobacterium marinum

BACKGROUND

Recently, the number of cases of Mycobacterium marinum infection has increased. Due to the nonspecific clinical manifestations and lack of standardized treatment guidelines, these infections are often misdiagnosed and are challenging to treat.

METHODS

In this study, four patients had M. marinum skin infections accompanied by a high-risk exposure history and were diagnosed by bacterial culture and gene chip. Two patients were treated with antibiotic therapy alone, and the other two patients were treated with 5-aminolevulinic acid photodynamic therapy (ALA-PDT) combined with antibiotics.

RESULTS

All four patients enrolled in the study were cured with 100 % efficacy. Two patients were cured after receiving two active antibiotics for 4 months. The other two patients, having considered the drug resistance and intolerance described above, were cured after receiving two active antibiotics for 1-1.5 months along with combination therapy with ALA-PDT.

CONCLUSION

Combination therapy with ALA-PDT and antibiotics was chosen to shorten the duration of antibiotic treatment and reduce the occurrence of adverse reactions.

Photodynamic therapy: a new approach to the treatment of Nontuberculous Mycobacterial skin and soft tissue infections

Nontuberculous mycobacterial skin and soft tissue infections are rising and are causing social concern due to the growth of cosmetic dermatology and immune-compromised populations. For the treatment of nontuberculous mycobacteria, several novel strategies have been investigated. One of them, photodynamic therapy, is a recently developed therapeutic strategy that has shown promise in managing nontuberculous mycobacterial skin and soft tissue infections. In this review, we first present an overview of the current status of the therapy and then summarize and analyze the cases of photodynamic therapy used to treat nontuberculous mycobacterial skin and soft tissue infections. We also discussed the feasibility of photodynamic therapy for treating nontuberculous mycobacterial skin soft tissue infections and the related mechanisms, providing a potential new option for clinical treatment.

ALA_PDT Promotes Ferroptosis-Like Death of Mycobacterium abscessus and Antibiotic Sterilization via Oxidative Stress

Mycobacterium abscessus is one of the common clinical non-tuberculous mycobacteria (NTM) that can cause severe skin infection. 5-Aminolevulinic acid photodynamic therapy (ALA_PDT) is an emerging effective antimicrobial treatment. To explore whether ALA_PDT can be used to treat M. abscessus infections, we conducted a series of experiments in vitro. We found that ALA_PDT can kill M. abscesses. Mechanistically, we found that ALA_PDT promoted ferroptosis-like death of M. abscesses, and the ROS scavenger N-Acetyl-L-cysteine (NAC) and ferroptosis inhibitor Ferrostatin-1 (Fer-1) can mitigate the ALA_PDT-mediated sterilization. Furthermore, ALA_PDT significantly up-regulated the transcription of heme oxygenase MAB_4773, increased the intracellular Fe2+ concentration and altered the transcription of M. abscessus iron metabolism genes. ALA_PDT disrupted the integrity of the cell membrane and enhanced the permeability of the cell membrane, as evidenced by the boosted sterilization effect of antibiotics. In summary, ALA_PDT can kill M. abscesses via promoting the ferroptosis-like death and antibiotic sterilization through oxidative stress by changing iron metabolism. The study provided new mechanistic insights into the clinical efficacy of ALA_PDT against M. abscessus.