Cutaneous Mycobacterium neoaurum infection causing scarring alopecia in an immunocompetent host

Antimicrobial Resistance in Rapidly Growing Nontuberculous Mycobacteria among Domestic and Wild Animals Emphasizing the Zoonotic Potential

Non-tuberculous mycobacteria (NTM) are opportunistic pathogens capable of causing infections in humans and animals. The aim of this study was to demonstrate the potential role of domestic and wild animals as a reservoir of multiple resistant, rapidly growing NTM strains representing a potential zoonotic threat to humans. A total of 87 animal isolates belonging to 11 rapidly growing species (visible colonies appear within three to seven days) were genotyped and tested for susceptibility to the 15 most commonly used antibiotics in the treatment of such infections in a human clinic. By determining the antimicrobial susceptibility, the most prevalent resistance was found to cephalosporins (>50%), followed by amoxicillin-clavulanate (31.0%), clarithromycin (23.0%), tobramycin (14.9%) and doxycycline (10.3%). Resistance to imipenem, ciprofloxacin, minocycline and linezolid was notably lower (<7.0%). All tested isolates were susceptible to amikacin and moxifloxacin. The most frequent resistance was proved in the most pathogenic species: M. fortuitum, M. neoaurum, M. vaccae and M. porcinum. Meanwhile, other species displayed a higher sensitivity rate. No significant resistance differences between domestic and wild animals were found. The established significant frequency of resistance highlights the significant zoonotic potential posed by circulating rapidly growing NTM strains, which could lead to challenges in the treatment of these infections.

A case report of cutaneous infection with Mycobacterium neoaurum

Cutaneous infection due to Mycobacterium neoaurum in immune-competent individuals had only been reported in limited cases. The point that makes our case very impressive was its cutaneous infection, and presentation in the immune-competent patient.

Abstract

Cutaneous infections caused by nontuberculous mycobacteria usually occur in immunocompromised hosts. We report a rare case of cutaneous infection caused by Mycobacterium neoaurum in an immune-competent patient.

Pin tract infection caused by Mycobacterium neoaurum in a 14-year-old child: A case report

Although rapidly growing non-tuberculosis mycobacterium can occasionally cause postoperative infections, Mycobacterium neoaurum is a rare pathogen of surgical site infection. We report a case of pin tract infection caused by M. neoaurum in a 14-year-old girl who was admitted for lengthening of her right fourth metatarsal bone. Pain, redness, and exudate were observed 18 days after external fixator insertion. Repeated exudate cultures revealed M. neoaurum, and she was diagnosed with a mycobacterial pin tract infection. She was initially administered intravenous ciprofloxacin and minocycline, and then was switched to oral trimethoprim-sulfamethoxazole and minocycline for a total of 6 months. Despite the pin tract infection, bone lengthening was completed under antibiotic treatment without removal of the pin; no other complications were noted. There are no prior reports of external fixator pin tract infection by M. neoaurum. While such cases may be rare, this case demonstrates that bone distraction may still be successfully completed using appropriate antibiotic therapy without pin removal.

Mycobacterium neoaurum line-related bacteremia with pulmonary involvement: Case report and review of literature

Mycobacterium neoaurum is a rapidly growing non-tuberculous mycobacterium which is ubiquitous in nature. While it can cause line related infections in immunocompromised host, case reports of urinary tract infections, cutaneous infections, pulmonary infections, and meningoencephalitis have also been reported. We report the first case of Mycobacterium neoaurum line related bacteremia with concomitant pulmonary involvement. Our patient responded well to a nine week course of antimicrobials after removal of infected central line.

Pulmonary infection caused by Mycobacterium neoaurum: the first case in Korea

Mycobacterium neoaurum is rapidly growing mycobacteria that can cause human infections. It commonly causes bloodstream infections in immunocompromised hosts, and unlike other mycobacteria species, it rarely causes pulmonary infections. We confirmed the first pulmonary infection case in Korea caused by M. neoaurum using full-length 16S rRNA gene sequencing.

Mycobacterium neoaurum and Mycobacterium bacteremicum sp. nov. as causes of mycobacteremia

Reference isolates of Mycobacterium neoaurum, Mycobacterium aurum, and the nonvalidated species "Mycobacterium lacticola" were the focus of two recent molecular taxonomic studies. On the basis of this grouping, we identified 46 clinical pigmented, rapidly growing mycobacterial isolates. By 16S rRNA gene sequencing, only two major taxa were identified: M. neoaurum and a previously uncharacterized "M. neoaurum-like" group. The M. neoaurum-like group exhibited only 99.7% identity to M. neoaurum by 16S rRNA gene sequencing and 96.5% identity to M. neoaurum by rpoB sequencing and was named M. bacteremicum. No clinical isolates of M. aurum or M. lacticola were identified. Of isolates with known sources, 4/8 (50%) of M. bacteremicum isolates and 22/34 (65%) of M. neoaurum isolates were recovered from blood, and 35% of these were known to be from patients with catheter-related sepsis. MIC and clinical data on these 46 isolates of M. neoaurum and M. bacteremicum along with a review of 16 previously reported cases of infection with the M. neoaurum-M. lacticola group demonstrated that the isolates were highly susceptible to all drugs tested except clarithromycin, and most clinical cases were successfully treated. The clarithromycin resistance suggested the presence of an inducible erm gene reported in other species of rapidly growing mycobacteria. Sequencing studies are currently required to identify these two species. Strain ATCC 25791 (originally submitted as an example of Mycobacterium aurum) is proposed to be the type strain of M. bacteremicum.