Microbiologic and Clinical Description of Postoperative Central Nervous System Infection After Endoscopic Endonasal Surgery.

BACKGROUND: Consensus guidelines for antibiotic prophylaxis in endoscopic endonasal surgery (EES) have not been developed. The study objective was to define the microbiologic and clinical characteristics of post-EES central nervous system (CNS) infections. METHODS: This was a single-center retrospective study of patients >18 years of age who underwent EES between January 2010 and July 2021 at a high-volume skull base center. Patients with confirmed CNS infection within 30 days of EES were included. During the study period, the standard prophylaxis regimen was ceftriaxone 2 g every 12 hours for 48 hours. For patients with a documented penicillin allergy, vancomycin plus aztreonam was recommended. RESULTS: In total, 2440 EES procedures were performed on 2005 patients; the CNS infection rate was 1.8% (37/2005). CNS infections were more common among patients with a history of previous EES (6.5%; 20/307) compared with those who did not (1%; 17/1698; P < 0.001). The median time from EES to CNS infection was 12 (6-19) days. Thirty-two percent (12/37) of CNS infections were polymicrobic, which was more common among patients without previous EES (52.9%; 9/17) compared with those with previous EES (15%; 3/20; P = 0.03). Across all cases, Staphylococcus aureus (n = 10) and Pseudomonas aeruginosa (n = 8) were commonly isolated pathogens. Among those with confirmed methicillin-resistant Staphylococcus aureus (MRSA) nares colonization before EES, 75% (3/4) developed MRSA CNS infections compared with 6.1% (2/33) of noncolonized patients (P = 0.005). CONCLUSIONS: CNS infection after EES is rare and causative pathogens vary. Further studies are needed to identify the impact of MRSA nares screening on antimicrobial prophylaxis before EES.

Risk Factors, Screening, and Treatment Challenges in Staphylococcus aureus Native Septic Arthritis.

BACKGROUND: Staphylococcus aureus is the most common cause of native septic arthritis. Few studies have characterized this disease during the US opioid epidemic. The role of methicillin-resistant Staphylococcus aureus (MRSA) nasal screening in this disease has not been elucidated. We sought to identify risk factors and outcomes for S. aureus native septic arthritis and to evaluate MRSA screening in this disease. METHODS: A retrospective cohort study of native septic arthritis patients (2012-2016) was performed. Demographics, risk factors, and outcomes were compared between Staphylococcus aureus and other native septic arthritis infections. Sensitivity, specificity, and predictive values of MRSA screening were assessed. RESULTS: Two hundred fifteen cases of native septic arthritis were included. S. aureus was cultured in 64% (138/215). MRSA was cultured in 23% (50/215). S. aureus was associated with injection drug use (odds ratio [OR], 4.33; 95% CI, 1.74-10.81; P = .002) and switching antibiotics (OR, 3.92; 95% CI, 1.01-21.38; P = .032). For every 10-year increase in age, the odds of S. aureus decreased (OR, 0.72; 95% CI, 0.60-0.87; P = .001). For 1-unit increases in Charlson comorbidity index score, the odds of S. aureus decreased (OR, 0.82; 95% CI, 0.73-0.91; P = .0004). MRSA screening during admission demonstrated a sensitivity of 0.59, specificity of 0.96, positive predictive value of 0.85, and negative predictive value of 0.84 for MRSA native septic arthritis. CONCLUSIONS: The opioid epidemic may be contributing to a demographic shift in native septic arthritis to younger, healthier individuals. S. aureus native septic arthritis has unique risks, including injection drug use. MRSA screening may be useful to rule in MRSA native septic arthritis.

Plasma and Cerebrospinal Fluid Therapeutic Drug Monitoring of Ceftolozane and Tazobactam During Treatment of Multidrug-Resistant Pseudomonas aeruginosa Meningitis.

We report a case of multidrug-resistant Pseudomonas aeruginosa meningitis treated with ceftolozane-tazobactam with concomitant therapeutic drug monitoring of plasma and cerebral spinal fluid. The data suggest that ceftolozane-tazobactam may be an option for select central nervous system infections; however, treatment decisions should be interpreted on a case-by-case basis.

2017 Infectious Diseases Society of America's Clinical Practice Guidelines for Healthcare-Associated Ventriculitis and Meningitis.

The Infectious Diseases Society of America (IDSA) Standards and Practice Guidelines Committee collaborated with partner organizations to convene a panel of 10 experts on healthcare-associated ventriculitis and meningitis. The panel represented pediatric and adult specialists in the field of infectious diseases and represented other organizations whose members care for patients with healthcare-associated ventriculitis and meningitis (American Academy of Neurology, American Association of Neurological Surgeons, and Neurocritical Care Society). The panel reviewed articles based on literature reviews, review articles and book chapters, evaluated the evidence and drafted recommendations. Questions were reviewed and approved by panel members. Subcategories were included for some questions based on specific populations of patients who may develop healthcare-associated ventriculitis and meningitis after the following procedures or situations: cerebrospinal fluid shunts, cerebrospinal fluid drains, implantation of intrathecal infusion pumps, implantation of deep brain stimulation hardware, and general neurosurgery and head trauma. Recommendations were followed by the strength of the recommendation and the quality of the evidence supporting the recommendation. Many recommendations, however, were based on expert opinion because rigorous clinical data are not available. These guidelines represent a practical and useful approach to assist practicing clinicians in the management of these challenging infections.

Adverse Events Lead to Drug Discontinuation More Commonly among Patients Who Receive Nafcillin than among Those Who Receive Oxacillin.

Nafcillin and oxacillin are used interchangeably in clinical practice, yet few studies have evaluated the safety of these two agents. Our objective was to compare the differential tolerabilities of nafcillin and oxacillin among hospitalized patients. We conducted a retrospective cohort study of all patients who received 12 g/day of nafcillin or oxacillin for at least 24 h. Two hundred twenty-four patients were included. Baseline characteristics and comorbidities were similar among patients receiving nafcillin (n = 160) and those receiving oxacillin (n = 64). Hypokalemia, defined as a potassium level of ≤3.3 mmol/liter or ≤2.9 mmol/liter or as a ≥0.5-mmol/liter decrease from the baseline level, occurred more frequently among patients who received nafcillin (51%, 20%, and 56%, respectively) than among those who received oxacillin (17%, 3%, and 34%, respectively; P < 0.0001, P = 0.0008, and P = 0.005, respectively). By multivariate logistic regression analysis, receipt of nafcillin was an independent predictor of severe hypokalemia (odds ratio [OR] = 6.74; 95% confidence interval [CI], 1.46 to 31.2; P = 0.02). Rates of hepatotoxicity did not differ between groups; however, acute kidney injury occurred more commonly with nafcillin than with oxacillin (18% versus 6%; P = 0.03). Overall, 18% of patients who received nafcillin discontinued therapy prematurely due to adverse events, compared to 2% of patients who received oxacillin (P = 0.0004). Nafcillin treatment is associated with higher rates of adverse events and treatment discontinuation than oxacillin among hospitalized adult patients. These findings have important implications for patients in both inpatient and outpatient settings, particularly patients who require long-term therapy and cannot be monitored routinely. Future randomized controlled studies evaluating the efficacy, costs, and tolerability of nafcillin versus oxacillin are warranted.

Malignant Otitis Externa: Evolving Pathogens and Implications for Diagnosis and Treatment.

OBJECTIVE: Malignant otitis externa (MOE) is an invasive infection of the temporal bone that is classically caused by Pseudomonas aeruginosa. Increasingly, however, nonpseudomonal cases are being reported. The goal of this study was to evaluate and compare the clinical presentation and outcomes of cases of MOE caused by Pseudomonas versus non-Pseudomonas organisms. STUDY DESIGN: Retrospective case series with chart review. SETTING: Tertiary care institution. SUBJECTS AND METHODS: Adult patients with diagnoses of MOE between 1995 and 2012 were identified. Charts were reviewed for history, clinical presentation, laboratory data, treatment, and outcomes. RESULTS: Twenty patients diagnosed with and treated for MOE at the University of Pittsburgh Medical Center between 1995 and 2012 were identified. Nine patients (45%) had cultures that grew P aeruginosa. Three patients (15%) had cultures that grew methicillin-resistant Staphylococcus aureus (MRSA). Signs and symptoms at presentation were similar across groups. However, all of the patients with Pseudomonas had diabetes, compared with 33% of MRSA-infected patients (P = .046) and 55% of all non-Pseudomonas-infected patients (P = .04). Patients infected with MRSA were treated for an average total of 4.7 more weeks of antibiotic therapy than Pseudomonas-infected patients (P = .10). Overall, patients with non-Pseudomonas infections were treated for a total of 2.4 more weeks than Pseudomonas-infected patients (P = .25). CONCLUSIONS: A high index of suspicion for nonpseudomonal organisms should be maintained in patients with signs and symptoms of MOE, especially in those without diabetes. MRSA is an increasingly implicated organism in MOE.

Traffic in the operating room: a review of factors influencing air flow and surgical wound contamination.

Surgical wound contamination leading to surgical site infection can result from disruption of the intended airflow in the operating room (OR). When personnel enter and exit the OR, or create unnecessary movement and traffic during the procedure, the intended airflow in the vicinity of the open wound becomes disrupted and does not adequately remove airborne contaminants from the sterile field. An increase in the bacterial counts of airborne microorganisms is noted during increased activity levels within the OR. Researchers have studied OR traffic and door openings as a determinant of air contamination. During a surgical procedure the door to the operating room may be open as long as 20 minutes out of each surgical hour during critical procedures involving implants. Interventions into limiting excessive movement and traffic in the OR may lead to reductions in surgical site infections in select populations.

Endoscopic endonasal skull base surgery: analysis of complications in the authors' initial 800 patients.

OBJECT: The development of endoscopic endonasal approaches, albeit in the early stages, represents part of the continuous evolution of skull base surgery. During this early period, it is important to determine the safety of these approaches by analyzing surgical complications to identify and eliminate their causes. METHODS: The authors reviewed all perioperative complications associated with endoscopic endonasal skull base surgeries performed between July 1998 and June 2007 at the University of Pittsburgh Medical Center. RESULTS: This study includes the data for the authors' first 800 patients, comprising 399 male (49.9%) and 401 female (50.1%) patients with a mean age of 49.21 years (range 3-96 years). Pituitary adenomas (39.1%) and meningiomas (11.8%) were the 2 most common pathologies. A postoperative CSF leak represented the most common complication, occurring in 15.9% of the patients. All patients with a postoperative CSF leak were successfully treated with a lumbar drain and/or another endoscopic approach, except for 1 patient who required a transcranial repair. The incidence of postoperative CSF leaks decreased significantly with the adoption of vascularized tissue for reconstruction of the skull base (< 6%). Transient neurological deficits occurred in 20 patients (2.5%) and permanent neurological deficits in 14 patients (1.8%). Intracranial infection and systemic complications were encountered and successfully treated in 13 (1.6%) and 17 (2.1%) patients, respectively. Seven patients died during the 30-day perioperative period, 6 of systemic illness and 1 of infection (overall mortality 0.9%). CONCLUSIONS: Endoscopic endonasal skull base surgery provides a viable median corridor based on anatomical landmarks and is customized according to the specific pathological process. This corridor should be considered as the sole access or may be combined with traditional approaches. With the incremental acquisition of skills and experience, endoscopic endonasal approaches have an acceptable safety profile in select patients presenting with various skull base pathologies.

One thousand endoscopic skull base surgical procedures demystifying the infection potential: incidence and description of postoperative meningitis and brain abscesses.

BACKGROUND: Endonasal endoscopic skull base surgery (ESBS) is perceived as having a high risk of infection because it is performed through the sinuses, which are not sterile. OBJECTIVE: To identify the bacteriological characteristics, incidence, mortality, and risk factors for intracranial infection after ESBS. METHODS: A retrospective analysis of the first 1,000 ESBS procedures performed at the University of Pittsburgh Medical Center from 1998 to 2008. RESULTS: In 18 cases (1.8%), the patient developed meningitis. In 2 cases, the patient died within 2 months after surgery, of noninfectious causes. In 11 cases, cerebrospinal fluid (CSF) cultures had positive results. There were no predominant pathogens. Male sex (odds ratio [OR], 3.97 [95% confidence interval {CI}, 1.21-13.03]; P = .02), history of a craniotomy or endonasal surgery (OR, 4.77 [95% CI, 1.68-13.56]; P = .02), surgery with higher levels of complexity (OR, 6.60 [95% CI, 1.77-24.70]; P = .003), the presence of an external ventricular drain or ventriculoperitoneal shunt at the time of surgery (OR, 6.38 [95% CI, 1.07-38.09]; P = .005), and postoperative CSF leak (OR, 12.99 [95% CI, 4.24-39.82]; P < .001) were risk factors for infection. CONCLUSION: The incidence of infection of 1.8% in ESBS is comparable to that in open craniotomy. The most important risk factor was a postoperative CSF leak. All patients recovered from their infection.

Gingival hypertrophy: a solitary manifestation of scurvy.

A 48-year-old woman presented with rapid onset hypertrophy of both the upper and lower gingiva. A detailed history and a diet nearly void of fruits and vegetables raised the suspicion of a possible deficiency of vitamin C. An estimation of the serum ascorbic acid level confirmed our suspicions (<0.12 mg/dL; normal range, 0.4-1.0 mg/dL) and a diagnosis of scurvy was confirmed. A course of 1000 mg/d of ascorbic acid was initiated that caused a dramatic resolution of the gingival lesions. Gingival hypertrophy has a large differential diagnosis; however, it is also known to be an extremely rare manifestation of scurvy. A high index of suspicion for scurvy is relevant given its low prevalence in developed nations and how easily remediable the disease can be, even when it presents in a severe form.

Influenza vaccination rates and motivators among healthcare worker groups.

BACKGROUND: The rate of influenza vaccination among healthcare workers (HCWs) is approximately 40%. Differences in vaccination rates among HCW groups and reasons for accepting or rejecting vaccination are poorly understood. OBJECTIVES: To determine vaccination rates and motivators among different HCW groups during the 2004-2005 influenza season. DESIGN: Cross-sectional survey conducted between July 10 and September 30, 2005. SETTING: Two tertiary care teaching hospitals in an urban center. PARTICIPANTS: Physicians, nurses, nursing aides, and other staff. Surveys were collected from 1,042 HCWs (response rate, 42%). RESULTS: Sixty-nine percent of physicians (n=282) and 63% of medical students (n=145) were vaccinated, compared with 46% of nurses (n=336), 42% of nursing aides (n=135), and 29% of administrative personnel (n=144). Physicians and medical students were significantly more likely to be vaccinated than all other groups (P<.0001). Pediatricians (84%) were more likely than internists (69%) and surgeons (43%) to be vaccinated (P<.0001). Among the HCWs who were vaccinated, 33.4% received the live attenuated influenza vaccine (LAIV) and 66.6% received trivalent inactivated influenza vaccine (TIV). Vaccinated HCWs were less likely than unvaccinated HCWs to report an influenza-like illness (P=.03). Vaccination with LAIV resulted in fewer episodes of influenza-like illness than did receiving no vaccine (P=.03). The most common reason for rejecting vaccination was a concern about availability. Understanding that HCWs may transmit the virus to patients correlated with vaccine acceptance (P=.0004). CONCLUSIONS: Significant differences in vaccination exist among physician specialties and employee groups, and there are inadequate vaccination rates among those with the greatest amount of patient contact, potentially providing a basis for group-specific interventions.

Postoperative discitis due to Propionibacterium acnes: a case report and review of the literature.

BACKGROUND: No previous report has described a progressive, destructive postoperative discitis requiring operative stabilization due to Propionibacterium acnes. The clinical and radiographic features and treatment options associated with discitis due to P acnes are presented in a retrospective case study, as well as a review of the current literature. CASE DESCRIPTION: Seven weeks after a routine lumbar discectomy, the patient presented with clinical findings and radiographic imaging consistent with discitis. Intraoperative cultures obtained from irrigation and debridement of the disc space revealed P acnes, and appropriate intravenous antibiotic treatment was instituted. Approximately 2 months later, the patient showed progression to a destructive osteomyelitis requiring operative stabilization. Nine weeks after stabilization, the patient continued to have lower back pain without radiculopathy. Laboratory values had normalized. Radiographic imaging revealed good instrumentation positioning and adequate fusion. The patient was ambulatory with bilateral articulating ankle foot orthoses and a walker. CONCLUSION: The reported case adds to the literature on postoperative discitis due to P acnes and demonstrates that this organism can occasionally be the cause of progressive, destructive osteomyelitis. In addition, we review the incidence, risk factors, and clinical course of discitis due to P acnes.

Meropenem administered as a prolonged infusion to treat serious gram-negative central nervous system infections.

The treatment of gram-negative infection of the central nervous system (CNS) presents a clinical challenge due to antibiotic resistance and difficulties with penetration into the cerebrospinal fluid (CSF). Two patients with gram-negative CNS infections were treated successfully with high-dose, prolonged infusions of meropenem. The CSF meropenem concentrations exceeded the minimum inhibitory concentration of the pathogen for virtually the entire dosing interval in both cases. Our experience demonstrates that dosage modification to maximize pharmacodynamic targets and bactericidal activity may be practically applied to optimize antibiotic treatment for difficult-to-treat CNS infections.

Duration of colonization with vancomycin-resistant Enterococcus.

OBJECTIVE: To determine the duration of colonization with vancomycin-resistant Enterococcus (VRE) and the adequacy of 3 consecutive negative cultures to determine clearance. DESIGN: Retrospective cohort study. SETTING: A university hospital. POPULATION: Patients identified by perirectal cultures as VRE carriers who had follow-up cultures. METHODS: Follow-up perirectal cultures were collected in inpatient and outpatient settings, at least 1 week apart, when patients were not receiving antibiotics with activity against VRE. The likelihood of culture positivity was analyzed given prior culture results and time from the initial positive culture. RESULTS: A total of 116 patients colonized with VRE had 423 follow-up cultures, a mean of 204 days (range, 4 to 709 days) after their initial isolate. The first follow-up culture, collected a mean of 125 days after the initial positive isolate, was negative in 64%. After 1 negative follow-up culture, the next one was negative in 92% of the patients. After 2 negative cultures, 95% remained culture-negative. After 3 sequential negative cultures, 35 (95%) of 37 patients remained culture-negative. As the interval between the initial and the follow-up isolates increased, the probability that a subsequent culture would be positive decreased (P < .001, chi square for trend). Prolonged hospitalization, intensive care, and antibiotic use each decreased the likelihood of clearing VRE. CONCLUSION: These data support the Centers for Disease Control and Prevention criterion of 3 sequential negative cultures, at least 1 week apart, to remove patients from VRE isolation. Nevertheless, this may reflect a decrease in the quantity of VRE to an undetectable level and these patients should be observed for relapse, especially when re-treated with antibiotics.