Prevalence of Transfusion-Transmitted Virus Among Human Immunodeficiency Virus – Infected Subjects in Northern Italy

At surgery on 29 January 1998, there were large abscess cavities anterior to both right and left pectoral muscle flaps that contained a large volume of purulent material. Specimens of this material were submitted for routine cultures for bacteria and fungi as well as for Mycoplasma and Ureaplasma species. Doxycycline (100 mg intravenously twice daily) was added empirically to the therapeutic regimen of vancomycin and piperacillin/tazobactam. U. urealyticum was isolated in pure culture. Therapy with vancomycin and piperacillin/tazobactam was discontinued, and he received doxycycline therapy for a total of 67 days. His wound healed without incident, and he was doing well 10 months after the operation. Although extragenital infections due to U. urealyticum have been reported [1–5], they are rare. The true incidence of these infections is unknown, but the real importance of this pathogen may be underestimated. Review of the literature revealed only two reported cases of poststernotomy infection involving U. urealyticum, but in both reports, Mycoplasma hominis was isolated as a copathogen [6, 7]. To our knowledge, our case is the only report of postoperative mediastinitis due to U. urealyticum alone. Ureaplasma species require urea for growth and cannot be recovered on routine bacteriologic media. This case points out the importance of utilizing gram staining for diagnosis. Gram staining showed many polymorphonuclear leukocytes but no organisms. Ureaplasma species are weakly staining gram-negative organisms that are usually not visualized by gram staining. Had specific cultures for Ureaplasma species not been performed, ineffective therapy with broad-spectrum agents would have likely continued for this patient. When confronted with cases of culture-negative sternal wound infections or mediastinitis, clinicians should consider the possibility of ureaplasmal or mycoplasmal infection and perform appropriate cultures.