Mediastinal Mucormycosis: Case report, review of literature and treatment with continuous liposomal amphotericin B irrigation.

Mediastinal mucormycosis is an uncommon but lethal infection associated with an 83% mortality. We describe a case of fatal Rhizopus microsporus mediastinitis despite three exploratory mediastinal surgeries and complementary systemic and mediastinal irrigation with liposomal amphotericin B. We further review the literature on surgical and antifungal management of mediastinal mucormycosis.

The ACS NSQIP Risk Calculator Is a Fair Predictor of Acute Periprosthetic Joint Infection.

BACKGROUND: Periprosthetic joint infection (PJI) is a severe complication from the patient's perspective and an expensive one in a value-driven healthcare model. Risk stratification can help identify those patients who may have risk factors for complications that can be mitigated in advance of elective surgery. Although numerous surgical risk calculators have been created, their accuracy in predicting outcomes, specifically PJI, has not been tested. QUESTIONS/PURPOSES: (1) How accurate is the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) Surgical Site Infection Calculator in predicting 30-day postoperative infection? (2) How accurate is the calculator in predicting 90-day postoperative infection? METHODS: We isolated 1536 patients who underwent 1620 primary THAs and TKAs at our institution during 2011 to 2013. Minimum followup was 90 days. The ACS NSQIP Surgical Risk Calculator was assessed in its ability to predict acute PJI within 30 and 90 days postoperatively. Patients who underwent a repeat surgical procedure within 90 days of the index arthroplasty and in whom at least one positive intraoperative culture was obtained at time of reoperation were considered to have PJI. A total of 19 cases of PJI were identified, including 11 at 30 days and an additional eight instances by 90 days postoperatively. Patient-specific risk probabilities for PJI based on demographics and comorbidities were recorded from the ACS NSQIP Surgical Risk Calculator website. The area under the curve (AUC) for receiver operating characteristic (ROC) curves was calculated to determine the predictability of the risk probability for PJI. The AUC is an effective method for quantifying the discriminatory capacity of a diagnostic test to correctly classify patients with and without infection in which it is defined as excellent (AUC 0.9-1), good (AUC 0.8-0.89), fair (AUC 0.7-0.79), poor (AUC 0.6-0.69), or fail/no discriminatory capacity (AUC 0.5-0.59). A p value of < 0.05 was considered to be statistically significant. RESULTS: The ACS NSQIP Surgical Risk Calculator showed only fair accuracy in predicting 30-day PJI (AUC: 74.3% [confidence interval {CI}, 59.6%-89.0%]. For 90-day PJI, the risk calculator was also only fair in accuracy (AUC: 71.3% [CI, 59.9%-82.6%]). Conclusions The ACS NSQIP Surgical Risk Calculator is a fair predictor of acute PJI at the 30- and 90-day intervals after primary THA and TKA. Practitioners should exercise caution in using this tool as a predictive aid for PJI, because it demonstrates only fair value in this application. Existing predictive tools for PJI could potentially be made more robust by incorporating preoperative risk factors and including operative and early postoperative variables. LEVEL OF EVIDENCE: Level III, diagnostic study.

Campath-1H induction and the incidence of infectious complications in adult renal transplantation.

BACKGROUND: The purpose of this study was to evaluate adult renal transplantation patients who received a alemtuzumab (Campath-1H)-based induction protocol for the incidence of infectious complications. METHODS: We began using 30 mg Campath-1H intravenously for induction therapy in May 2003. The patients were treated with a maintenance regimen of tacrolimus or mycophenolate mofetil (MMF), and rapidly tapered prednisone; valganciclovir was used for CMV prophylaxis. Forty-nine adult patients who received renal transplants between May 1, 2003 and June 7, 2004 were included. The mean follow-up time was 13.7 months with a range of 10-24 months. Data were collected via a retrospective chart review. RESULTS: The infectious complications noted in the Campath-1H group were compared with a historical group of 56 patients receiving conventional immunosuppression. There was one case of cytomegalovirus (CMV) viremia and two cases of CMV disease (one pneumonitis and one enteritis). There were four cases of urinary tract infection and one extremity cellulitis. One patient developed Cryptococcal meningitis. Eight of the 49 (16%) patients in the Campath group had an infectious complication, compared to 18 out of 56 (32%) in the historical group. CONCLUSION: Campath-1H induction for renal transplantation appears to have a low incidence of associated infectious complications when compared to historical regimens.

Identification of Cardiobacterium hominis by broad-range bacterial polymerase chain reaction analysis in a case of culture-negative endocarditis.

Culture-negative bacterial endocarditis may be attributed to fastidious microorganisms, prior institution of antibiotic treatment, or both. We describe a case of culture-negative endocarditis in which a modified Steiner stain revealed bacterial structures in the resected heart valve material. Prompted by this finding, broad-range polymerase chain reaction (PCR) amplification of small-subunit ribosomal DNA (16S rDNA) was performed, and Cardiobacterium hominis sequences were detected. This case demonstrates the usefulness of both the Steiner stain and broad-range direct molecular amplification as supplemental diagnostic tools in identification of otherwise unexplained infections.

Osteomyelitis resulting from chronic filamentous fungus olecranon bursitis.

We describe a case of Phaeoacremonium olecranon osteomyelitis. The patient, initially felt to have traumatic olecranon bursitis, was found to have an indolent filamentous fungus cultured from the olecranon bursa. In retrospect, x-rays revealed bony erosion, which heightened the index of suspicion for infection in this particular case. Surgical bursal excision was performed and antifungal therapy was administered with clinical resolution. This case emphasizes that aspiration, synovial fluid analysis, and culture of bursal fluid is essential in excluding typical and atypical causes of chronic bursitis.

Implantable defibrillator pocket infection and bacteremia caused by Nocardia nova complex isolate.

Nocardia spp. are common environmental organisms that, to our knowledge, have never been implicated as causing an implantable defibrillator or pacemaker infection. We describe a 70-year-old male with a recent implantable cardiac defibrillator revision and subsequent device infection and bacteremia caused by a Nocardia nova complex isolate.