Mycoplasma hominis osteitis in an immunocompetent man

Unexpected Mycoplasma hominis infection in two renal transplant recipients traced back to the same donor by whole-genome sequencing

Mycoplasma hominis is a common colonizer of the lower genitourinary tract. Although its clinical relevance for causing urogenital infections in immunocompetent individuals is controversial, this bacterium has been involved in severe invasive infections in allograft recipients. In this report, we describe two cases of M. hominis infection in two young renal transplant recipients within the first month post-transplant. Although at first no epidemiological link between the two cases had been suspected, whole-genome sequencing (WGS) analysis showed that both isolates were identical, highly suggestive of an origin with the common organ donor.

Mycoplasma hominis Infections Transmitted Through Amniotic Tissue Product

Background

Mycoplasma hominis is a commensal genitourinary tract organism that can cause infections outside the genitourinary tract. We investigated a cluster of M. hominis surgical site infections in patients who underwent spine surgery, all associated with amniotic tissue linked to a common donor.

Methods

Laboratory tests of tissue product from the donor, including culture, quantitative real-time polymerase chain reaction (qPCR), and whole-genome sequencing were performed. Use of this amniotic tissue product was reviewed. A multistate investigation to identify additional cases and locate any unused products was conducted.

Results

Twenty-seven tissue product vials from a donor were distributed to facilities in 7 states; at least 20 vials from this donor were used in 14 patients. Of these, 4 of 14 (29%) developed surgical site infections, including 2 M. hominis infections. Mycoplasma hominis was detected by culture and qPCR in 2 unused vials from the donor. Sequencing indicated >99% similarity between patient and unopened vial isolates. For 5 of 27 (19%) vials, the final disposition could not be confirmed.

Conclusions

Mycoplasma hominis was transmitted through amniotic tissue from a single donor to 2 recipients. Current routine donor screening and product testing does not detect all potential pathogens. Clinicians should be aware that M. hominis can cause surgical site infections, and may not be detected by routine clinical cultures. The lack of a standardized system to track tissue products in healthcare facilities limits the ability of public health agencies to respond to outbreaks and investigate other adverse events associated with these products.

[Mycoplasma hominis bacteremia. An underestimated etiological agent]

Mycoplasma hominis is a fastidious bacterium, which usually colonizes the lower urogenital tract and may cause systemic infections in neonates and genital infections in adults. It can also be the cause of serious extra-genital infections, mainly in immunosuppressed or predisposed subjects.

CASE PRESENTATION

We describe a case of bacteremia caused by M. hominis in a previously healthy woman after uterine curettage due to incomplete abortion. M. hominis could be an underestimated cause of bacteremia in immunocompetent patients. Mycoplasma organisms have fastidious growth requirements, are often difficult to culture on a cell-free medium and have no cell wall. The conventional method for detection may fail. This is the first report of M. hominis isolation from a positive automated blood culture (BD BACTEC, USA).

Decompressive Laminectomy Complicated by Postoperative Mycoplasma hominis Epidural Abscess and Meningitis in a Young Woman: A Case Report

CASE

A twenty-eight-year-old woman underwent decompressive laminectomy and placement of an interlaminar stabilizer due to L4/L5 disc herniation. Thirteen days later she developed a fever unresponsive to meropenem and vancomycin, along with signs of meningitis. A Mycoplasma hominis epidural abscess was identified. She had no preoperative risk factors for extragenital M. hominis infection, but had had a urinary catheter inserted intraoperatively.

CONCLUSION

M. hominis postoperative surgical site infection is a rarely identified complication of spinal surgery. Seeding from the genitourinary tract is the most likely source.

New Diagnostic Real-Time PCR for Specific Detection of Mycoplasma hominis DNA

Mycoplasma hominis is a fastidious micro-organism causing genital and extragenital infections. We developed a specific real-time PCR that exhibits high sensitivity and low intrarun and interrun variabilities. When applied to clinical samples, this quantitative PCR allowed to confirm the role of M. hominis in three patients with severe extragenital infections.

[Two cases of septic arthritis by Mycoplasma hominis after total knee replacement arthroplasty]

Mycoplasma hominis has been related with pelvic inflammatory illnesses and postpartum and neonatal infections. Extragenital M. hominis infections are rare, but septicemia, septic arthritis, wound infection, meningitis, and other infections in Immunocompromised patients have also been described. Here we report two cases of septic arthritis caused by M. hominis in patients following total knee replacement arthroplasty. After the surgery, the patients presented with knee pain and clinical signs of infection, such as fever, erythema and swelling on the surgical site. Arthroscopic debridement operations were performed on the surgical site. M. hominis was isolated from the joint fluid and identified by the microscopic visualization of the typical "fried-egg-type" colonies on Mycoplasma specific agar (pleuropneumonia-like organism agar). It was also confirmed by 16S rRNA sequencing. To the best of our knowledge, this is the first report of prosthetic joint infections with M. hominis in Korea.

A case of Mycoplasma hominis septic arthritis postpartum

A 17-year-old woman presented 1-week post caesarean section with septic arthritis which was unresponsive to first-line empirical antimicrobial therapy. Cultures of the hip aspirate revealed Mycoplasma hominis as the causative organism. M. hominis-associated septic arthritis is extremely rare in the absence of underlying joint abnormalities or immunosuppression. Strikingly four of the 26 cases reported have been pregnancy-associated.