A Comparison Between the Clinical Features of Pseudotumor Cerebri Secondary to Tetracyclines and Idiopathic Intracranial Hypertension

PURPOSE

Comparisons between clinical features of tetracycline-induced pseudotumor cerebri (PTC-T) and those of idiopathic intracranial hypertension (IIH) are absent in the literature. We hypothesized that significant clinical differences between these etiologies exist and could be better understood by retrospective analysis.

DESIGN

Retrospective cohort study.

METHODS

We reviewed patients diagnosed with pseudotumor cerebri syndrome (PTCS) at our center and identified those who developed PTC-T after treatment with a tetracycline-class antibiotic and those with IIH. Groups were compared by demographics, body mass index, ophthalmic examination, treatment, clinical course, and visual outcomes.

RESULTS

We identified 52 cases of PTC-T and 302 cases of IIH. Obesity rates were significantly different (43.8% for PTC-T vs 79.2% for IIH, P < .001). The mean age at diagnosis was younger for PTC-T (19.8 years vs 28.1 years for IIH, P < .001). Diplopia was more common with PTC-T (40.4% vs 20.1% for IIH, P = .001). The mean illness duration was shorter for PTC-T (18.3 weeks vs 62.9 weeks for IIH, P <.0001). Recurrence rates were significantly different (4.0% for PTC-T vs 16.5% for IIH, P <.001). The frequency of surgical intervention was similar. Vision loss was uncommon but occurred with similar frequency.

CONCLUSION

We identified significant clinical differences but also identified important similarities between the 2 groups. There appear to be nonobese patients who develop PTC-T, discontinue the antibiotic, and never develop PTCS again. There are other patients who develop PTC-T, discontinue the antibiotic, and later develop IIH. We conclude that PTC-T represents a spectrum of disease in susceptible individuals.

Addressing Suicide in the Veteran Population: Engaging a Public Health Approach

Suicide is a national public health issue in America, and it disproportionately affects those who are serving or who have served in the United States military. The US Department of Veterans Affairs (VA) has made suicide prevention its number one clinical priority. VA is committed to prevent suicide among the entire population of those who have served our country in the military, regardless of whether they make use of any VA services or benefits. Suicide can be prevented through the application of a public health strategy embracing partners at all levels. Following a national strategy, VA has embarked on an effort involving the application of a public health strategy combining both clinically-based and community-focused interventions. This paper describes several examples of these efforts and steps forward.

On- and off-label utilization of dalbavancin and oritavancin for Gram-positive infections

BACKGROUND

Long-acting lipoglycopeptides (laLGPs) are FDA approved only for acute bacterial skin and skin structure infections (ABSSSIs). However, these antibiotics show promise for off-label use, reductions in hospital length of stay (LOS) and healthcare cost savings.

OBJECTIVES

To assess the effectiveness, safety, impact on LOS and estimated cost savings from laLGP treatment for Gram-positive infections.

METHODS

Retrospective cohort of adult patients who received at least one dose of laLGPs at the University of Colorado Health system. Descriptive statistics were utilized for analysis.

RESULTS

Of 59 patients screened, 56 were included: mean age 47 years, 59% male and 30% injection drug users/polysubstance abusers (dalbavancin, 71%; oritavancin, 25%; both, 4%). Most common indications for laLGP: ABSSSIs (36%), osteomyelitis (27%) and endocarditis (9%). Most common isolated pathogens: MSSA and MRSA (25% and 19%, respectively), Enterococcus faecalis (11%) and CoNS (11%). Previous antibiotics were administered for a median of 13 days (IQR = 7.0-24.5 days) and laLGPs for a median of one dose (IQR = 1-2 doses). Ten (18%) patients were lost to follow-up. Clinical failure was found in 7/47 (15%) cases with adequate follow-up. Mild adverse effects occurred in six (11%) patients. Projected reduction in hospital LOS and health-system costs were 514 days (9.18 days/person average) and $963456.72 ($17204.58/person average), respectively.

CONCLUSIONS

Prospective trials are needed to validate the use of these antibiotics for Gram-positive infections in practice, with the hope that they will reduce hospital LOS and the need for daily antibiotic infusions to provide alternative options for patients not qualifying for outpatient parenteral antimicrobial therapy.

Severe acute Q fever pneumonia complicated by presumed persistent localized Q fever endocarditis in a renal transplant recipient: A case report and review of the literature

Q fever in solid organ transplant (SOT) recipients is rarely described in the medical literature. We present a case of severe acute Q fever pneumonia that evolved into persistent localized Q fever endocarditis in a renal transplant recipient.

218. Evaluation of Clinical Outcomes with Shorter Vs. Longer Duration of Treatment for Common Inpatient Bacterial Infections Associated with Bacteremia

Background

Pneumonia (PNA), urinary tract infection (UTI), and acute bacterial skin and skin structure infection (ABSSSI) are the most common infections treated in the inpatient setting and often are associated with bacteremia. Though short courses of treatment are advocated for these infections in general, no established guidelines exist for cases involving bacteremia. We evaluated the clinical outcomes of patients receiving short (5–9 days) vs. long (10–15 days) duration of antibiotic treatment.

Methods

A retrospective study was conducted at 3 area hospitals comprising a university-based tertiary center, a public safety net hospital, and a Veterans’ Affairs hospital. We included hospitalized adult patients with transient bacteremia associated with uncomplicated cases of PNA, UTI, or ABSSSI. The primary outcome consisted of a composite of rehospitalization or resumption of antibiotic treatment attributed to the original infection or death due to any cause within 30 days of the antibiotic start date. Secondary outcomes included the individual composite components, Clostridioides difficile infection, and antibiotic-related adverse effects leading to change in antibiotic therapy. A propensity score weighted logistic regression model was used to mitigate factors which could bias a patient toward receiving a shorter or longer treatment duration.

Results

Of 411 patients included in the study, 123 (29.9%) received a short duration of therapy and 288 (70.1%) received a long duration of therapy. The median duration of treatment was 8 days in the short group and 13 days in the long group. In the propensity-weighted analysis, the probability of meeting the composite primary outcome was not statistically different between the short and long groups (Table 1). However, receiving a short course was associated with a higher probability of restarting antibiotics and Clostridioides difficile infection.

Conclusion

Shorter vs. longer courses of antibiotic treatment for bacteremia associated with PNA, UTI, and ABSSSI were not significantly different in a composite of readmission, restart of antibiotics, and mortality; however, further study is needed to evaluate the safety and effectiveness of short-course therapy.

Disclosures

All authors: No reported disclosures.

1021. Accuracy of Provider-Selected Antibiotic Indications at Point of Order Entry Compared with Electronic Health Record Documentation

Background

The Centers for Medicaid and Medicare Services (CMS) state that hospital antimicrobial stewardship (AMS) policies require indications be documented for all orders. This may be included in the electronic medical record (EMR) or during order entry per CMS. Reliance solely on EMR documentation may be inconsistent or absent at times. In an effort to optimize compliance to this new measure and improve antibiotic use tracking, the University of Colorado AMS committee implemented required indications for all systemic antimicrobial orders. To follow up on this intervention we sought to determine the accuracy of ordered indication based on EMR documentation.

Methods

Retrospective review of antibiotics ordered between May 2, 2017 and December 1, 2017 among hospitalized patients aged 18–89 years. The primary objective was the accuracy of provider-selected indications (PSI) compared with EMR documented-clinical indication (DCI). Secondary objectives included accuracy comparison between check-box and free-text PSI format, and adherence to institutional antibiotic use guidelines. Differences between proportions of antibiotic orders with certain variables were assessed with Pearson’s chi-square and Fisher’s exact as appropriate.

Results

A total of 304 patients were evaluated with a median age of 56 years, 49% male, and 31% identified as immunocompromised. Check-box was most utilized in 81%, with 93% having a single indication selected. Most orders were classified as empiric (63%), followed by prophylaxis (23%) and definitive (15%). Frequent indications chosen were pneumonia (17%), bacteremia (13%), skin and soft tissue (10%), urinary tract infection (9%), and intra-abdominal infections (5%). Accuracy by PSI/DCI match was 78%, which was not different by a method of indication entry. Only indication type (P = 0.023) and care team specialty (P = 0.009) were shown to significantly impact accuracy. Nonadherence to institutional guidelines was 19%.

Conclusion

Antibiotic indications on order entry are an effective strategy to improve documentation and meet compliance around new CMS standards. Ordering by surgical services and prophylactic indications had lower PSI/DCI match, mostly resulting from absent EMR indication documentation.

Disclosures

All authors: No reported disclosures.

2287. Real-world Use of Tedizolid Phosphate: A Case Series of Long-Term Tolerability

Background

Tedizolid is an oxazolidinone antibiotic with broad-spectrum Gram-positive activity approved for the treatment of skin and skin structure infections with a 6-day course. Oxazolidinone antibiotics represent appealing options for prolonged antimicrobial therapy due to their available oral formulations with excellent bioavailability and potent in vitro activity against various multidrug-resistant Gram-positive organisms, Mycobacterium spp., and Nocardia spp. Although tedizolid and linezolid offer a similar clinical spectrum based on antimicrobial activity alone, long-term use of linezolid is often limited by serious adverse effects. Preliminary assessments have suggested better tolerability with tedizolid; however, these are limited by shorter exposure duration. The objective of this study was to evaluate the long-term safety and tolerability of tedizolid.

Methods

Retrospective cohort of adult patients receiving tedizolid for ≥ 28 days, with baseline complete blood cell (CBC) indices available, and CBC indices drawn ≥ 14 days into tedizolid course. The primary objective was to evaluate the long-term tolerability of tedizolid.

Results

13 patients met inclusion criteria: median age 61 years (IQR, 51–64 years), 69% male, 85% Caucasian. The majority of patients utilized tedizolid for suppression (85%), and the median duration of tedizolid was 113 days (IQR, 71–204 days). There were no differences in CBC indices when comparing baseline to last laboratory draw throughout tedizolid exposure: platelets (baseline: 203 x 10⁹/L (IQR, 186–283 x 10⁹/L) vs. last: 196 x 10⁹/L (IQR, 161–303 x 10⁹/L; p = 0.65), hemoglobin (baseline: 9.8 g/dL (IQR, 8.8–11.1 g/dL) vs. last: 11.7 g/dL (IQR, 11.0–13.1 g/dL; p = 0.10), and white blood cells (baseline: 6.2 x 10⁹/L (IQR, 5.6–7.6 x 10⁹/L) vs. last: 6.5 x 10⁹/L (IQR, 6.3–7.3 x 10⁹/L; p = 0.45). The final laboratory draws were obtained a median of 78 days (IQR, 44–119 days) into therapy. No patients experienced peripheral neuropathy, optic neuritis/visual changes, or serotonin syndrome during treatment/suppression with tedizolid during the period evaluated.

Conclusion

Long-term therapy with tedizolid appears to be well-tolerated. Treatment and suppression with tedizolid seems to be a safe alternative to linezolid.

Disclosures

All authors: No reported disclosures.

1116. Impact of Antimicrobial Stewardship Incentive Goals for Pharmacists on Overall Antibiotic Use and Appropriate Duration of Therapy in Urinary Tract Infections

Background

Urinary tract (UTI), skin and soft tissue, and respiratory infections are among the most frequently reported indications for antibiotics, such that focusing stewardship efforts here would expectedly have dramatic effects. Antimicrobial stewardship (AMS) programs vary in structure and available resources. At the University of Colorado Hospital, a 740-bed academic medical center, dedicated resources for AMS are limited to a pharmacist, pharmacy resident, and physician; however, there is a large clinical pharmacist group. For the past 2 years, pharmacy management incorporated AMS targets as group goals tied to performance bonuses.

Methods

This is a descriptive report utilizing incentives to achieve AMS goals. The first goal (July 1, 2016 to June 30, 2017) set out to reduce inpatient antibiotic use by 10%. The second goal (July 1, 2018 to June 30, 2018) was a 10% reduction in median antibiotic duration for UTIs. The AMS team provided guidelines, education, and oversight throughout target periods. Antibiotic use was calculated as days of therapy (DOT) per 1000 patient-days. Data related to UTI treatment was collected retrospectively on a quarterly basis. This was compared with baseline data previously collected during a statewide hospital stewardship collaborative project.

Results

During the first period, overall antibiotic use declined from 497 to 403 DOT per 1000 patient-days (18.9%), and broad-spectrum antibiotic use declined 22%. During the second period, 30 patient charts were reviewed quarterly, and the median UTI duration declined from 10 to 7 days (P = 0.002). The most common UTI diagnoses were similar between periods with complicated cystitis and pyelonephritis comprising 60–70% of cases. The 30-day readmission rate was not different between the baseline and goal period, 11% vs. 6% respectively (P = 0.18).

Conclusion

The use of group pharmacist goals tied to annual performance bonuses was effective in achieving AMS goals at our institution. In larger facilities with fewer dedicated AMS personnel, clinical pharmacists covering ward and intensive care units are an essential resource to achieving AMS goals. Group performance incentives may be a feasible strategy to generate interest and motivation to achieve AMS program goals.

Disclosures

All authors: No reported disclosures.

1535. Pharmacokinetic (PK) and Pharmacodynamic (PD) Evaluation of Cefepime (CPM) in Obese and Non-Obese Patients

Background

Appropriate application of antimicrobial PK/PD properties is crucial to optimizing patient outcomes. Although β-lactams are among the most utilized and effective antibiotics, optimal dosing strategies in obese populations are largely unknown. The objective of this study was to compare PK/PD of CPM in non-obese (NO, weight 80–100 kg) and obese (O, weight > 100 kg) patients.

Methods

A prospective comparative PK/PD analysis was conducted in NO and O patients receiving CPM. Blood samples were obtained at 30, 60, 120, 240, 360, and 480 minutes after CPM infusion. CPM concentrations were determined by reversed-phase high-performance liquid chromatography. Non-compartmental PK analyses were performed, followed by Monte Carlo simulations (Oracle Crystal Ball®, 5,000 simulated patients) to estimate probability of target attainment (PTA) against common Gram-negative pathogens. The desired PD target for CPM was % time above MIC of unbound drug (%fT > MIC) ≥ 60%. Chi-squared and Mann–Whitney U tests were used for analysis.

Results

Seventeen patients were enrolled and most (94%) received CPM 2 g q8h. A significant difference in actual body weight and body mass index was observed (P < 0.001). There were no differences in other baseline or PK characteristics between the two groups. Utilizing CPM 2 g q8h, PTA ≥ 90% was not observed for organisms with an MIC of 8 μg/mL, the current CLSI breakpoint for P. aeruginosa and A. baumannii (PTA = 88% vs. 81% in NO and O groups, respectively). With a 6 g continuous infusion (CI), however, ≥ 90% PTA was achieved in both groups (PTA = 100%) for organisms with an MIC of 8 μg/mL, while a regimen of 2 g q8h (infused over 3 hours [EI]) also provided PTA of ≥ 90% in both groups (PTA = 98% vs. 92% in NO and O groups, respectively). Goal PTA was not obtained in either group for organisms with an MIC of 4 μg/mL with CPM 1 g q8h or 2 g q12h (i.e., CLSI recommended dosing for organisms with MICs of 4 μg/mL).

Conclusion

Optimizing PK/PD parameters through novel dosing strategies are essential in both the NO and O populations for optimal CPM exposure in susceptible pathogens with higher MICs. CPM 6 grams/day by either CI or EI provides more optimal PK/PD characteristics in obese patients for pathogens with MICs at or near the current CLSI-recommended breakpoint.

Disclosures

All authors: No reported disclosures.

Oral Vancomycin Prophylaxis as Secondary Prevention Against Clostridioides difficile Infection in the Hematopoietic Stem Cell Transplantation and Hematologic Malignancy Population

Clostridioides difficile infection (CDI) is a common complication in the hematopoietic stem cell transplantation (HSCT) and hematologic malignancy (HM) population. CDI is associated with increased hospital length of stay, health care and societal costs, morbidity, and mortality. Identifying strategies for secondary prevention of CDI is of extreme importance in the HSCT/HM population. In this study, our primary objective was to evaluate the effectiveness and safety of an oral vancomycin prophylaxis (OVP) protocol for secondary prevention of CDI in a retrospective cohort of adult autologous/allogeneic HSCT recipients and patients with HM who did not undergo HSCT with a first CDI episode treated with concomitant broad-spectrum antibiotics (BSA). Patients were diagnosed and treated for CDI as inpatients and/or outpatients and were divided into 2 groups based on a preprotocol versus postprotocol analysis: the OVP group, comprising patients who received planned monotherapy with oral vancomycin 125 mg every 6 hours for 14 days for a first episode of CDI and subsequently received OVP posttreatment and a no OVP (NOVP) group, comprising patients who received planned monotherapy with oral vancomycin 125 mg every 6 hours for 14 days for a first episode of CDI and subsequently did not receive OVP posttreatment. OVP was defined as vancomycin 125 mg every 12 hours for up to 7 days after BSA discontinuation. The primary endpoint was recurrent CDI (rCDI), defined as symptoms of loose stools/diarrhea with high clinical suspicion for CDI prompting empiric therapy within 60 days of completion of treatment/prophylaxis for the first CDI episode. The incidence of vancomycin-resistant enterococcal (VRE) infection and 60-day mortality were also compared between the 2 groups. Multivariate logistic regression was created from associated variables to identify independent associations with rCDI. A total of 50 patients were included, 21 in the OVP group (42%) and 29 in the NOVP group (58%). The mean patient age was 58 years, and the cohort was 60% male and 86% Caucasian. HSCT was performed in 60% of the patients, and 76% of CDI cases were diagnosed during hospitalization. The rate of rCDI was significantly lower in the OVP group compared with the NOVP group (5% [1 of 21] versus 35% [10 of 29]; P= .016), with no subsequent increase in VRE infection rate (14% [3 of 21] versus 10% [3 of 29]; P = .686). By multivariable logistic regression, rCDI was inversely associated with OVP (odds ratio [OR], .14; 95% confidence interval [CI], .007 to .994; P = .049) and directly associated with outpatient CDI diagnosis (OR, 8.72; 95% CI, 1.816 to 49.158; P = .007). No between-group differences were found in 60-day mortality (10% [2 of 21] for OVP versus 7% [2 of 29] for NOVP; P > 0.999). OVP appears to be safe and effective for secondary prevention of CDI in the HSCT/HM population. Prospective trials are needed to validate the effectiveness of OVP in this vulnerable population to prevent rCDI.

Long-Acting Lipoglycopeptides: "Lineless Antibiotics" for Serious Infections in Persons Who Use Drugs

Background

Injection drug use is associated with serious infections. Due to challenges with medical management of addiction, relapses and additional infections are common. Persons who use drugs (PWUD) are more likely to leave against medical advice before completing treatment, which could result in treatment failure. Prolonged intravenous (IV) antimicrobial therapy in PWUD may be complicated by concern for IV catheter misuse, sometimes requiring prolonged hospitalization. Ideal alternatives would provide the following: (1) high success rate; (2) reduced rate of medical complications; (3) improved safety profiles; and (4) improved cost-effectiveness. Long-acting lipoglycopeptides present such opportunity for treatment of serious Gram-positive infections.

Methods

We performed a system-wide, retrospective analysis of adults admitted to University of Colorado Health from September 2015 to June 2018 and treated with dalbavancin or oritavancin based on clinical judgment of their treating physicians.

Results

Fifty-six patients met inclusion criteria (17 PWUD vs 39 non-PWUD). The PWUD group were younger, healthier by Charlson comorbidity index, more likely insured by Medicaid, and admitted for conditions requiring longer treatment. Ten patients were lost to follow-up. Of the patients with follow-up, clinical failure was met in 1 PWUD patient (6%) and 6 non-PWUD patients (15%) (P = .413). The median hospital length-of-stay reduction was 20 days (interquartile range [IQR], 10–30 days) in PWUD vs 11 days (IQR, 9–14 days) in non-PWUD; P = .133. Estimated median savings were $40 455.08 (IQR, $20 900.00–$62 700.00) in PWUD vs $19 555.08 (IQR, $15 375.08–$23 735.08) in non-PWUD; P = .065.

Conclusions

Long-acting lipoglycopeptides may be equally effective as standard-of-care, present a safety advantage, and secure earlier discharge and significant cost-savings.

MetaUniDec: High-Throughput Deconvolution of Native Mass Spectra

The expansion of native mass spectrometry (MS) methods for both academic and industrial applications has created a substantial need for analysis of large native MS datasets. Existing software tools are poorly suited for high-throughput deconvolution of native electrospray mass spectra from intact proteins and protein complexes. The UniDec Bayesian deconvolution algorithm is uniquely well suited for high-throughput analysis due to its speed and robustness but was previously tailored towards individual spectra. Here, we optimized UniDec for deconvolution, analysis, and visualization of large data sets. This new module, MetaUniDec, centers around a hierarchical data format 5 (HDF5) format for storing datasets that significantly improves speed, portability, and file size. It also includes code optimizations to improve speed and a new graphical user interface for visualization, interaction, and analysis of data. To demonstrate the utility of MetaUniDec, we applied the software to analyze automated collision voltage ramps with a small bacterial heme protein and large lipoprotein nanodiscs. Upon increasing collisional activation, bacterial heme-nitric oxide/oxygen binding (H-NOX) protein shows a discrete loss of bound heme, and nanodiscs show a continuous loss of lipids and charge. By using MetaUniDec to track changes in peak area or mass as a function of collision voltage, we explore the energetic profile of collisional activation in an ultra-high mass range Orbitrap mass spectrometer. Graphical abstract ᅟ.

Comparing Surfactant Penetration into Human Skin and Resulting Skin Dryness Using In Vivo and Ex Vivo Methods

Numerous tests have been developed to estimate a surfactant's mildness in rinse-off formulations. In this study, mixed surfactant systems were examined for their impact on surfactant penetration into the skin and skin hydration using in vivo and ex vivo methods. A forearm controlled application test (FCAT) was conducted, and skin hydration was evaluated using corneometry and visual dryness grading. Tape strip and cup scrub extractions were completed within the FCAT to examine the penetration of five individual surfactants into the skin in vivo. The ratio of surfactant mass extracted by five pooled tape strips to surfactant mass extracted by cup scrubs was found to be in the range of 40-59%. Furthermore, cup scrub collection and analysis was less time-consuming and less expensive to conduct than tape stripping. Thus, we recommend cup scrub extraction as a suitable substitute for tape stripping in future surfactant skin penetration analyses. In vivo results were compared with ex vivo ¹⁴C-sodium dodecyl sulfate (¹⁴C-SDS) penetration into human cadaver skin from the same surfactant systems. In vivo measurements conducted in the FCAT, including corneometer reading, visual dryness score, and individual surfactant (sodium laureth (1) ether sulfate and cocamidopropyl betaine) extracted from the skin, were found to correlate well with ¹⁴C-SDS penetration into the skin ex vivo for anion-based surfactant systems. Thus, ¹⁴C-SDS skin penetration may be a useful preclinical test for skin dryness induced by rinse-off products containing anionic surfactants.

Applications of Immunopharmacogenomics: Predicting, Preventing, and Understanding Immune-Mediated Adverse Drug Reactions

Adverse drug reactions (ADRs) are a significant health care burden. Immune-mediated adverse drug reactions (IM-ADRs) are responsible for one-fifth of ADRs but contribute a disproportionately high amount of that burden due to their severity. Variation in human leukocyte antigen ( HLA) genes has emerged as a potential preprescription screening strategy for the prevention of previously unpredictable IM-ADRs. Immunopharmacogenomics combines the disciplines of immunogenomics and pharmacogenomics and focuses on the effects of immune-specific variation on drug disposition and IM-ADRs. In this review, we present the latest evidence for HLA associations with IM-ADRs, ongoing research into biological mechanisms of IM-ADRs, and the translation of clinical actionable biomarkers for IM-ADRs, with a focus on T cell-mediated ADRs.

A comparison of safety and outcomes with cefazolin versus nafcillin for methicillin-susceptible Staphylococcus aureus bloodstream infections

BACKGROUND

Methicillin-susceptible Staphylococcus aureus (MSSA) is a frequent cause of bloodstream infections (BSI). Treatment with nafcillin (NAF) has been preferred to cefazolin (CFZ). However, comparable outcomes have been found with CFZ with possibly lower risk for side-effects. This study compared safety and effectiveness of NAF versus CFZ for MSSA BSI.

METHODS

This single center retrospective study evaluated adults admitted with MSSA BSI who received NAF or CFZ. Patients receiving ≥24 h of antibiotics were included for safety analyses. Patients receiving NAF or CFZ for ≥75% of a 14 day minimum treatment course were assessed for clinical effectiveness. The primary safety outcome was incidence of renal toxicity with multiple secondary safety endpoints. Clinical success was defined as symptom resolution, repeat negative cultures, lack of additional therapy for presumed failure, and lack of recurrence within 30 days.

RESULTS

A total of 130 patients receiving NAF (n = 79) or CFZ (n = 51) were included for safety analysis. Of those, 90 met criteria for effectiveness assessment (NAF n = 40, CFZ n = 50). Baseline characteristics were well matched. NAF was associated with a higher incidence of nephrotoxicity compared to CFZ (25% vs. 2%, RR 1.31, 95% CI 1.15-1.5, p < 0.001), allergic reactions (p = 0.01) and a trend for hepatotoxicity (p = 0.08). Clinical success was achieved in 82% NAF and 94% CFZ treated patients (p = 0.1).

CONCLUSION

CFZ was associated with less nephrotoxicity and no difference in clinical success compared to NAF for MSSA BSI. A prospective study comparing NAF to CFZ for MSSA BSI should be conducted to elucidate differences in therapies.

Abrupt cloud clearing of marine stratocumulus in the subtropical southeast Atlantic

We document rapid and abrupt clearings of large portions of the subtropical marine low cloud deck that have implications for the global radiation balance and climate sensitivity. Over the southeast Atlantic, large areas of stratocumulus are quickly eroded, yielding partial or complete clearing along sharp transitions hundreds to thousands of kilometers in length that move westward at 8 to 12 meters per second and travel as far as 1000+ kilometers from the African coast. The westward-moving cloudiness reductions have an annual peak in occurrence in the period from April through June. The cloud erosion boundaries reduce cloud at ≈10-kilometer scale in less than 15 minutes, move approximately perpendicular to the mean flow, and are often accompanied by small-scale wave features. Observations suggest that the cloud erosion is caused by atmospheric gravity waves.

The Lupus Inhibitor: A Study of Its Heterogeneity

The plasmas of six patients with prolonged activated partial thromboplastin times were studied in detail. In five of the six, the Russell’s viper venom and prothrombin times were likewise prolonged. Five of the patients had documented systemic lupus erythematosus; one lacked the necessary criteria for this diagnosis. On quantitation, factor XI was decreased in all six; factors X and XII were diminished in five of the six. When tested for inhibitory activity, plasma from each of the patients prolonged the celite eluate inhibition test for factor XII and/or XI inhibition. In the formation of the Xa-V-phospholipid-Ca2+ complex (prothrombinase), factors X and Xa were inhibited to a greater degree than factor V or the phospholipid. Finally, each plasma was isofocused, the inhibitory fractions were identified and the clotting factor specificity of each inhibitory peak was determined.Fractions inhibitory against factors XI and XII isofocused with the IgG in each patient’s plasma. Based on the data presented from these six patients, the “lupus inhibitor” is in fact a heterogeneous collection of inhibitors directed against factors XII, XI and X rather than a homogeneous entity.

Antigen-specific interferon-gamma release is decreased following the single intradermal comparative cervical skin test in African buffaloes (Syncerus caffer)

Effective disease management of wildlife relies on the strategic application of ante-mortem diagnostic tests for early identification and removal of M. bovis-infected animals. To improve diagnostic performance, interferon-gamma release assays (IGRAs) are often used in conjunction with the tuberculin skin test (TST). Since buffaloes are major maintenance hosts of M. bovis, optimal application of bovine TB diagnostic tests are especially important. We aimed to determine whether the timing of blood collection relative to the TST has an influence on IFN-γ production and diagnostic outcome in African buffaloes. Release of IFN-γ in response to bovine purified protein derivative (PPD), avian PPD and PC-HP^® and PC-EC^® peptides was measured by Bovigam^® and an in-house IGRA in a group of Bovigam^®-positive and - negative buffaloes at the time the TST was performed and three days later. There was significantly lower IFN-γ release in response to these antigens post-TST in Bovigam^®-positive buffaloes, but no significant changes in Bovigam^®-negative buffaloes. Also, a significantly greater proportion of buffaloes were Bovigam^®-positive prior to the TST than three days later. We therefore recommend that blood samples for use in IGRAs be collected prior to or at the time the TST is performed to facilitate the correct identification of greater numbers of IGRA-positive buffaloes.

Seroprevalence of Mycobacterium bovis infection in warthogs (Phacochoerus africanus) in bovine tuberculosis-endemic regions of South Africa

Bovine tuberculosis (bTB), caused by Mycobacterium bovis (M. bovis), has been reported in many species including suids. Wild boar are important maintenance hosts of the infection with other suids, that is domestic and feral pigs, being important spillover hosts in the Eurasian ecosystem and in South Africa, warthogs (Phacochoerus africanus) may play a similar role in M. bovis-endemic areas. However, novel diagnostic tests for warthogs are required to investigate the epidemiology of bTB in this species. Recent studies have demonstrated that serological assays are capable of discriminating between M. bovis-infected and uninfected warthogs (Roos et al., ). In this study, an indirect ELISA utilizing M. bovis purified protein derivative (PPD) as a test antigen was used to measure the prevalence and investigate risk factors associated with infection in warthogs from uMhkuze Nature Reserve and the southern region of the Greater Kruger National Park (GKNP). There was a high overall seroprevalence of 38%, with adult warthogs having a higher risk of infection (46%). Seroprevalence also varied by geographic location with warthogs from Marloth Park in the GKNP having the greatest percentage of positive animals (63%). This study indicates that warthogs in M. bovis-endemic areas are at high risk of becoming infected with mycobacteria. Warthogs might present an under-recognized disease threat in multi-species systems. They might also serve as convenient sentinels for M. bovis in endemic areas. These findings highlight the importance of epidemiological studies in wildlife to understand the role each species plays in disease ecology.

Stability of the Syndesmosis After Posterior Malleolar Fracture Fixation

BACKGROUND

We sought to define the rate of syndesmotic instability after anatomic reduction of the posterior malleolus when posterior stabilization of a trimalleolar or trimalleolar equivalent ankle fracture was chosen vs when a supine position and initially conservative management of the posterior elements was chosen.

METHODS

The types of syndesmotic and posterior malleolar fixation used to treat adult patients with ankle fractures involving the posterior malleolus at our level I trauma center were retrospectively assessed (N = 198). Specifically, both bimalleolar and trimalleolar fractures were included. Exclusion criteria included pilon fractures, trimalleolar fractures with Chaput fragments, and neurologic injury. Demographics, fracture classification, initial operative position, medial clear space, and posterior malleolar fragment size were recorded for each fracture.

RESULTS

In total, 151 patients (76.3%) were initially positioned supine, 27.2% of whom had syndesmotic instability requiring operative stabilization. Almost 25% of supine patients also underwent posterior malleolar stabilization for posterior instability. Overall, 73 (48.3%) patients who were initially treated in the supine position needed some form of additional stabilization. Forty-seven patients (23.7%) were initially positioned prone. Syndesmotic stability was restored in 97.9% of these patients. This 2.1% rate of instability vastly differs from the 13-fold higher syndesmotic instability rate observed in the supine group ( P < .001).

CONCLUSION

Our data demonstrate that the rate of syndesmotic instability was reduced in trimalleolar and trimalleolar equivalent fractures when prone positioning and direct fixation of the posterior malleolus were first performed. Using traditional preoperative estimates of posterior stability to determine the need for posterior malleolar fixation may be inadequate since almost a quarter of patients treated supine received posterior stabilization.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Tuberculosis serosurveillance and management practices of captive African elephants (Loxodonta africana) in the Kavango-Zambezi Transfrontier Conservation Area

Transfrontier conservation areas represent an international effort to encourage conservation and sustainable development. Their success faces a number of challenges, including disease management in wildlife, livestock and humans. Tuberculosis (TB) affects humans and a multitude of non-human animal species and is of particular concern in sub-Saharan Africa. The Kavango-Zambezi Transfrontier Conservation Area encompasses five countries, including Zimbabwe, and is home to the largest contiguous population of free-ranging elephants in Africa. Elephants are known to be susceptible to TB; thus, understanding TB status, exposure and transmission risks to and from elephants in this area is of interest for both conservation and human health. To assess risk factors for TB seroprevalence, a questionnaire was used to collect data regarding elephant management at four ecotourism facilities offering elephant-back tourist rides in the Victoria Falls area of Zimbabwe. Thirty-five working African elephants were screened for Mycobacterium tuberculosis complex antibodies using the ElephantTB Stat-Pak and the DPP VetTB Assay for elephants. Six of 35 elephants (17.1%) were seropositive. The risk factor most important for seropositive status was time in captivity. This is the first study to assess TB seroprevalence and risk factors in working African elephants in their home range. Our findings will provide a foundation to develop guidelines to protect the health of captive and free-ranging elephants in the southern African context, as well as elephant handlers through simple interventions. Minimizing exposure through shared feed with other wildlife, routine TB testing of elephant handlers and regular serological screening of elephants are recommended as preventive measures.