Abscess resulting from Mycobacterium kansasii in the left thigh of AIDS patient

Huge cutaneous abscess and severe symptomatic hypercalcaemia secondary to Mycobacterium kansasii infection in an immunocompetent patient

Mycobacterium kansasii is among the most common non-tuberculous mycobacteria causing human infections. Apart from pulmonary infection, the most common infection caused by M. kansasii is skin and soft tissue infection, and it is very rare in immunocompetent people. In this report, we present a case of a huge cutaneous abscess caused by M. kansasii A 63-year-old man living in Bangkok presented with progressive pain at the left lateral chest wall for 3 weeks and altered mentation for a few days. Examination revealed a non-tender fluctuated cutaneous mass 20×10 cm in size. An aspiration of the mass yielded 50 mL pus with many positive acid-fast bacilli. Mycobacterial PCR was positive for M. kansasii with culture confirmation. There was severe hypercalcaemia. The treatment included surgical drainage, and medical treatment consisted of isoniazid, rifampicin, ethambutol and levofloxacin, along with adequate hydration and calcitonin for hypercalcaemia. The patient gradually improved and was discharged 12 days after hospitalisation.

Applying the One Health Concept to Mycobacterial Research - Overcoming Parochialism

Mycobacterial infections remain a public health problem. Historically important, globally ubiquitous and with a wide host range, we are still struggling to control mycobacterial infections in humans and animals. While previous reviews have focused on individual mycobacterial infections in either humans or animals, a comprehensive review of the zoonotic aspect of mycobacteria in the context of the One Health initiative is lacking. With the purpose of providing a concise and comprehensive resource, we have collated literature to address the zoonotic potential of different mycobacterial species and elaborate on the necessity for an inter-sectorial approach to attain a new vision to combat mycobacterial infections.

Enhanced antifungal effects of amphotericin B-TPGS-b-(PCL-ran-PGA) nanoparticles in vitro and in vivo

Background

Amphotericin B (AMB) is a polyene antibiotic with broad spectrum antifungal activity, but its clinical toxicities and poor solubility limit the wide application of AMB in clinical practice. Recently, new drug-loaded nanoparticles (NPs) – diblock copolymer D-α-tocopheryl polyethylene glycol 1000 succinate-b-poly(ε-caprolactone-ran-glycolide) (PLGA-TPGS) – have received special attention for their reduced toxicity, and increased effectiveness of drug has also been reported. This study aimed to develop AMB-loaded PLGA-TPGS nanoparticles (AMB-NPs) and evaluate their antifungal effects in vitro and in vivo.

Methods

AMB-NPs were prepared with a modified nanoprecipitation method and then characterized in terms of physical characteristics, in vitro drug release, stability, drug-encapsulation efficiency, and toxicity. Finally, the antifungal activity of AMB-NPs was investigated in vitro and in vivo.

Results

AMB-NPs were stable and spherical, with an average size of around 110 nm; the entrapment efficacy was closed to 85%, and their release exhibited a typically biphasic pattern. The actual minimum inhibitory concentration of AMB-NPs against Candida albicans was significantly lower than that of free AMB, and AMB-NPs were less toxic on blood cells. In vivo experiments indicated that AMB-NPs achieved significantly better and prolonged antifungal effects when compared with free AMB.

Conclusion

The AMB-PLGA-TPGS NP system significantly improves the AMB bioavailability by improving its antifungal activities and reducing its toxicity, and thus, these NPs may become a good drug carrier for antifungal treatment.