First case report of sepsis caused by Mycobacterium wolinskyi in chronic myelogenous leukemia

Catheter-related bloodstream Mycobacterium wolinskyi infection in an umbilical cord blood transplant recipient: a case report

Background

Catheter-related bloodstream infection (CRBSI), caused by rapidly growing mycobacteria (RGM), is a rare infectious complication in hematopoietic stem cell transplant (HSCT) recipients and can often be misdiagnosed as Gram-positive rod (GPR) bacteremia.

Case presentation

We present a case of CRBSI caused by Mycobacterium wolinskyi, a rare RGM, in a 44-year-old female patient who received an umbilical cord blood transplant.

Conclusions

Rapidly growing mycobacteria can stain as GPRs and may grow in routine blood culture media after 3–4 days of incubation. These features are not widely known to clinicians, and acid-fast staining is therefore recommended when unidentifiable GPRs are detected in blood cultures, especially in immunocompromised patients, such as those with hematologic malignancies or intravascular devices.

First case report of prosthetic valve endocarditis caused by Mycobacterium wolinskyi

To date, only 26 cases of Mycobacterium wolinskyi infections have been reported in humans. We herein report a first case of prosthetic valve endocarditis due to this organism after cardiovascular surgery. An 82-year-old man presented with repeat episodes of syncope and fever after aortic valve replacement, mitral valve replacement, left atrial appendage closure, and pulmonary vein isolation. Blood cultures maintained in aerobic bottles were repeatedly positive after 90-100 hours, and Gallium scan revealed abnormal accumulations in the sternum and left testis. While colonies formed by culturing the fluid of the parasternal area and blood cultures revealed gram-positive rods, we could not analyze the colony using matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF). M. wolinskyi was finally identified on 16S rRNA, hsp65, and rpoB gene sequencing. We treated the patient with multiple antimycobacterial drugs, i.e., amikacin, imipenem, and clarithromycin for 6 weeks, which was changed to oral ciprofloxacin and minocycline for 12 months. This case highlights the need to consider rapidly growing mycobacteria, including M. wolinskyi, if chronic fever persists from weeks to months after surgery, the blood culture is positive, and the organism is not identified. In addition, sequencing the 16S rRNA, hsp65, and rpoB genes is essential for diagnosis.

Mycobacterium wolinskyi Peritonitis after Peritoneal Catheter Embedment Surgery

Mycobacterium wolinskyi belongs to the Mycobacterium smegmatis group, which comprises rapidly growing non-tuberculous mycobacteria. The number of case reports on M. wolinskyi infections associated with postoperative wounds has increased in recent years. We herein report a case of peritonitis due to M. wolinskyi after peritoneal catheter embedment surgery. Identification was achieved based on 16S ribosomal RNA and rpoB gene sequencing of the isolate. The patient recovered following catheter removal and treatment with levofloxacin and minocycline for one month.

Draft Genome Sequence of Mycobacterium wolinskyi, a Rapid-Growing Species of Nontuberculous Mycobacteria

Mycobacterium wolinskyi is a nonpigmented, rapidly growing nontuberculous mycobacterium species that is associated with bacteremia, peritonitis, infections associated with implants/prostheses, and skin and soft tissue infections often following surgical procedures in humans. Here, we report the first functionally annotated draft genome sequence of M. wolinskyi CDC_01.

Facial skin and soft tissue infection caused by Mycobacterium wolinskyi associated with cosmetic procedures

Background

Mycobacteirum wolinskyi is a member of the Mycobacterium smegmatis group, which is less frequently found in clinical settings than other nontuberculous mycobacterium (NTM) species. However, its clinical significance has recently increased in opportunistic infections. This case is the first report of facial skin and soft tissue infection by M. wolinskyi complicating cosmetic procedures.

Case presentation

A 56-year-old Asian female patient with a history of receiving multiple facial cosmetic procedures over the preceding 2 years was admitted to our institution with swelling, local pain, and erythema on the right cheek. Mycobacteirum fortuitum complex isolated from a pus culture was identified as M. wolinskyi by rpoB sequencing. Metallic foreign bodies and abscess were detected by radiologic imaging. The pus was incised and drained. Treatment comprised clarithromycin (500 mg every 12 h), amikacin (200 mg every 8 h), and ciprofloxacin (400 mg every 6 h).

Conclusion

We report the first case of facial skin and soft tissue infection with M. wolinskyi after multiple cosmetic procedures of filler injection and laser lipolysis. Increased occurrence of NTM infection in nosocomial settings suggests the importance of appropriate treatment including culturing and rpoB gene sequencing when patients who have undergone cosmetic procedures display symptoms and signs of soft tissue infection indicative of NTM infection.

Mycobacterium wolinskyi infection confirmed by rpoB gene sequencing

Identification of rapidly growing mycobacteria (RGM) is problematic because there are many taxonomic changes. 16S rRNA gene is commonly used to identify Mycobacterium species, but alternative gene targets have been introduced for more accurate identification. We report a rare case of a prosthetic knee infection due to Mycobacterium wolinskyi. The isolate was not identified by 16S rRNA gene sequencing alone and substantially confirmed by rpoB gene sequencing. The identification was delayed because our laboratory did not routinely identify RGM to the species level. Simultaneous sequencing of both 16S rRNA and rpoB genes will allow rapid and accurate identification of M. wolinskyi isolates.

[Infections due to rapidly growing mycobacteria]

Rapidly growing mycobacteria (RGM) are ubiquitous in nature and widely distributed in water, soil and animals. During the past three decades we have observed a notable increment of infections caused by RGM, both localized and disseminated, as well as nosocomial outbreaks of contaminated medical equipment. The microbiological diagnosis of RGM infections includes direct microscopic observation and culture. The taxonomic identification is performed by phenotypic, biochemical, chromatographic and molecular biology techniques. The treatment differs from that of other mycobacteriosis like tuberculosis, owing to the variable in vitro susceptibility of the species of this group. The RGM are resistant to conventional antituberculous drugs, but can be susceptible to broad spectrum antimicrobial agents. In this study we comment on the significant aspects of human infections by RGM, including their biology, epidemiology, pathology, microbiological diagnosis, taxonomic identification, antimicrobial susceptibility and treatment.