Training a Drug to Do New Tricks: Insights on Stability of Meropenem Administered as a Continuous Infusion.

BACKGROUND: The antibiotic armamentarium used to combat multi-drug resistant organisms (MDROs) include carbapenems. Continuous infusion (CI) dosing is frequently employed to maximize beta-lactam efficacy; however, use of meropenem CI has been limited due to concerns with product instability. OBJECTIVE: The primary objective of this study was to quantify meropenem serum concentrations to reflect drug stability when administered as CI over 8- or 12-h exchanges. In addition, a stability experiment was performed to further establish meropenem integrity over 12 h. The secondary objectives were to assess the ability of meropenem to achieve target pharmacokinetic/pharmacodynamic (PK/PD) exposures relative to the minimum inhibitory concentration (MIC) of the pathogen, and to determine clinical cure. METHODS: This was a retrospective, observational study on use of CI meropenem (infused either over 8- or 12- h) at a 1% concentration. The stability experiment was conducted on 1% meropenem at room temperature. RESULTS: In 22 patients, a median meropenem daily dose of 6 g/day (range 2-6 g/day) resulted in a median serum concentration of 17.8 mg/L (interquartile range, 9.3-27.8 mg/L). In 95% of cases, meropenem delivered as CI resulted in free drug concentrations at or above the MIC of the pathogen for the entire dosing interval. Clinical cure was achieved in 80% of patients included in this review. The stability experiment revealed negligible drug degradation at the end of the 12-h dosing interval. CONCLUSIONS: The data from this study provides compelling evidence for the use of meropenem as CI utilizing either a 12- or 8-h exchange process.

Pulmonary arterial hypertension and acute respiratory distress syndrome in a patient with adult-onset stills disease.

Adult-onset Still's disease (AOSD) is an inflammatory disorder characterized by recurrent fevers, arthralgia, leukocytosis, and a salmon-colored rash. Diagnosis is made based on the Yamaguchi criteria. Various cardiac and pulmonary manifestations have been described in association with AOSD, including acute respiratory distress syndrome (ARDS) and pulmonary arterial hypertension (PAH). We describe the first case of both PAH and ARDS in a patient with AOSD who, despite aggressive therapy, declined rapidly and ultimately died. There was concern for pulmonary veno-occlusive disease given the rate of her decompensation, but this was found not to be the case on autopsy. Treatment of AOSD with cardiopulmonary involvement requires rapid identification of AOSD followed by aggressive immunosuppression.

A Review of Targeted Pulmonary Arterial Hypertension-Specific Pharmacotherapy.

Significant advances in the understanding of the pathophysiology of pulmonary arterial hypertension over the past two decades have led to the development of targeted therapies and improved patient outcomes. Currently, a broad armamentarium of pulmonary arterial hypertension-specific drugs exists to assist in the treatment of this complex disease state. In this manuscript, we provide a comprehensive review of the current Food and Drug Administration (FDA)-approved pulmonary arterial hypertension-specific therapies, and their supporting evidence for adults, targeting the nitric oxide, soluble guanylate cyclase, endothelin, and prostacyclin pathways.

Do patients with submassive pulmonary embolism benefit from thrombolytic therapy?

Despite growing interest in thrombolytic agents to treat submassive pulmonary embolism, their role in this scenario remains controversial. Needed is a way to identify patients with this condition who are at risk of clinical deterioration and who would benefit from thrombolytic therapy. Here, we review the use of thrombolytic agents in submassive pulmonary embolism to help distinguish the risk and benefits of this therapy.

Transitioning from parenteral to inhaled prostacyclin therapy in pulmonary arterial hypertension.

BACKGROUND: Parenteral prostacyclin therapy for PAH has allowed for improvements in functional status, quality of life and mortality. Parenteral therapies however carry an increased risk of line-associated complications. Inhaled prostacyclins are an attractive alternative therapy; however, limited data exists supporting the safety and outcomes after transition. METHODS: We describe a retrospective observational analysis of adults with PAH who were transitioned from a parenteral prostacyclin to inhaled treprostinil at our institution. Endpoints include duration of transition, hospital length of stay, adverse effects during transition, and cardiopulmonary function post transition. RESULTS: Eight patients were included, all of which were on triple therapy. Seven patients receiving intravenous prostacyclin therapy were transitioned in an ICU setting, while one patient was transitioned from subcutaneous treprostinil as an outpatient. The average ICU and hospital length of stay was 4.1 ± 0.7 days. Patient preference was the most common reason for transition (n = 5), followed by line complication (n = 2), and intolerance to parenteral therapy (n = 1). One adverse event was observed while initiating inhaled treprostinil that only required slowing of the transition process. On follow-up (19.6 ± 11.1 months) functional class did not change, and non-parametric test showed no change in 6MWD after transition (p = 0.62). One patient failed inhaled therapy necessitating transition back to intravenous therapy. CONCLUSION: Transitioning patients from parenteral to inhaled prostacyclin therapy can be safely accomplished in specialized centers over a 48-72 h period. Patient preference was overwhelming the most prevalent reason for transition.

A 61-Year-Old Man With Shortness of Breath, Ascites, and Lower Extremity Edema.

A 61-year-old man presented with an 18-month history of progressive shortness of breath on exertion, fatigue, worsening bilateral lower extremity edema, abdominal swelling, and increased assistance with activities of daily living. Pertinent past medical history included right-sided pneumonia secondary to Streptococcus pneumoniae that was complicated by empyema, requiring right-sided video-assisted thoracoscopic surgery with decortication 2 years earlier. He had a negative cardiac history, no recent travel in the last 3 years, and no known exposure to tuberculosis. His medications included aspirin and daily furosemide. His symptoms appeared to be refractory to diuretic therapy. Previous workup 6 months earlier included an echocardiography (ECHO) showing enlarged left and right atria with a normal ejection fraction, and a catheterization of the left side of the heart with reported normal left ventricular function and unobstructed coronary arteries.

Management of Intrapleural Sepsis with Once Daily Use of Tissue Plasminogen Activator and Deoxyribonuclease.

BACKGROUND: Pleural infection remains a significant cause of morbidity, mortality, prolonged hospital stay, and increased healthcare costs, despite advances in therapy. Twice daily intrapleural tissue plasminogen activator (tPA)/deoxyribonuclease (DNase) initiated at the time of diagnosis has been shown to significantly improve radiological outcomes and decrease the need for surgery. OBJECTIVES: To analyze our experience with once daily tPA/DNase for intrapleural sepsis. METHODS: Data derived from consecutive patients with empyema and complicated parapneumonic effusion who received once daily intrapleural tPA/DNase between January 2012 and August 2014 were reviewed. Measured outcomes included treatment success at 30 days, volume of pleural fluid drained, improvement in radiographic pleural opacity, length of hospital stay, need for surgery, and adverse events. RESULTS: 55 consecutive patients (33 male; mean age ± SD, 54.6 ± 16.1 years) were treated with once daily intrapleural tPA/DNase for 3 days. The majority of the patients (n = 51; 92.7%) were successfully managed without the need for surgical intervention. The mean change in pleural opacity measured on chest radiograph at day 7 was -28.8 ±17.6%. The median amount of fluid drained was 2,195 ml. No serious adverse events requiring discontinuation of intrapleural medications were observed. The most common complication was pain requiring escalating doses of analgesics (n = 8; 15%). Compliance with the protocol was excellent. CONCLUSION: Early administration of once daily intrapleural tPA/DNase for 3 days is safe, effective, and represents a viable option for the management of empyema and complicated parapneumonic effusion.

Vasovagal response secondary to permanent contraception device in pulmonary arterial hypertension.

Adequate contraception is an essential component of managing pulmonary hypertension in women of childbearing age. Intrauterine devices are a popular contraceptive choice for many women but are associated with a risk of vagal response upon placement in certain patients with pulmonary hypertension, which may not be well tolerated. More recently, newer permanent contraception devices have emerged in the market, such as the Essure. We describe the first case, to our knowledge, of vagal-associated response due to an Essure device placement.

Treatment of isolated mediastinal and hilar recurrence of lung cancer with bronchoscopic endobronchial ultrasound guided intratumoral injection of chemotherapy with cisplatin.

PURPOSE: A common pattern of recurrence in lung cancer after receiving full dose external beam radiation therapy (EBRT) to targeted sites is isolated mediastinal and hilar recurrence (IMHR). Treatment options for these patients are limited to palliative radiation, chemotherapy, and/or best supportive care. We describe our experience with treating IMHR with bronchoscopic endobronchial ultrasound (EBUS) guided intratumoral injection of cisplatin (ITC). METHODS: Patients treated between Jan 2009-September 2014 with ITC for IMHR were included. Patient demographics, tumor histology, size, concurrent therapy, location, number of sites treated, treatment sessions, and encounters were abstracted. Responses were analyzed on follow-up scans 8-12 weeks after the last treatment session using RECIST 1.1 criteria. Locoregional recurrence, progression-free survival (PFS), and overall survival were measured. RESULTS: 50 sites were treated in 36 patients (19 males, 17 females) with mean age 61.9±8.5 years. Eight sites treated on subsequent encounters were excluded and one patient had an unevaluable response, leaving 35 patients and 41 sites for final analysis. 24/35 (69%) had complete or partial response (responders), whereas 11/35 (31%) had stable or progressive disease (non-responders). There were no significant differences in response based on histology, size, and concurrent therapy. Median survival for the group was 8 months (95% CI of 6-11 mo). Responders had significantly higher survival and PFS than non-responders. Two patients treated with concurrent EBRT, developed broncho-mediastinal fistula. CONCLUSION: EBUS guided intratumoral cisplatin for IMHR appears to be safe and effective, and may represent a new treatment paradigm for this patient population.

Restoration of Patency to Central Airways Occluded by Malignant Endobronchial Tumors Using Intratumoral Injection of Cisplatin.

RATIONALE: Malignant airway obstruction is commonly found in patients with lung cancer and is associated with significant morbidity and mortality. Relieving malignant obstruction may improve symptoms, quality of life, and life expectancy. OBJECTIVES: The objective of this study was to analyze our experience with bronchoscopic endobronchial intratumoral injection of cisplatin for malignant airway obstruction. METHODS: We conducted a retrospective analysis of patients with malignant airway obstruction treated with bronchoscopic intratumoral injection of cisplatin. Patient characteristics, histology, degree of airway obstruction, procedural methods, treatment cycles, performance status, and therapeutic outcomes were evaluated. Tumor response was analyzed based on bronchoscopic measurements performed on completion the of final treatment session. Adverse events and overall survival were abstracted. MEASUREMENTS AND MAIN RESULTS: Between January 2009 and September 2014, 22 patients (10 men, 12 women; mean age ± SD, 64.4 ± 9.5 yr) were treated with one to four injections of 40 mg of cisplatin mixed in 40 ml of 0.9% NaCl. Treatments were completed 1 week apart. The primary etiologies of airway obstruction included squamous cell carcinoma (n = 11), adenocarcinoma (n = 6), small cell carcinoma (n = 2), large cell undifferentiated carcinoma (n = 1), and metastatic endobronchial cancer (n = 2). Twenty-one of 22 patients were evaluable for response. The majority of patients (15/21, 71.4%) responded to therapy, defined as greater than 50% relative reduction in obstruction from baseline. Treatment response was obtained regardless of tumor histology, concurrent systemic therapy, number of treatment cycles administered, performance status, or use of additional ablative interventions. Responders had significantly improved overall survival as compared with nonresponders, although the difference was small. Severe treatment-related side effects or complications were not observed. CONCLUSIONS: Subject to the limitations of a single-center retrospective study and a subjective primary outcome measure, we have demonstrated the feasibility of improving the patency of central airways that are largely or completely occluded by endobronchial malignant tumor using intraluminal injection of cisplatin. Additional longer-term, larger-scale safety and comparative effectiveness studies of this palliative treatment modality are warranted.

Titanium exposure and yellow nail syndrome.

Yellow nail syndrome is a rare disease of unclear etiology. We describe a patient who develops yellow nail syndrome, with primary nail and sinus manifestations, shortly after amalgam dental implants. A study of the patient's nail shedding showed elevated nail titanium levels. The patient had her dental implants removed and had complete resolution of her sinus symptoms with no change in her nail findings. Since the patient's nail findings did not resolve we do not believe titanium exposure is a cause of her yellow nail syndrome but perhaps a possible relationship exists between titanium exposure and yellow nail syndrome that requires further studies.

Clinical experience with prophylactic fondaparinux in critically ill patients with moderate to severe renal impairment or renal failure requiring renal replacement therapy.

BACKGROUND: Fondaparinux has an increased bleeding risk in patients with a CrCl ≤ 50 mL/min and is contraindicated if CrCl < 30 mL/min. Data regarding dosing and anti-Xa monitoring are lacking in this population. OBJECTIVE: To describe dosing, monitoring, and safety outcomes of prophylactic fondaparinux in critically ill patients with moderate to severe renal impairment, including renal replacement therapy (RRT). METHODS: Retrospective analysis from October 2006 to November 2012 of patients ≥ 18 years old who received fondaparinux for ≥ 72 hours with ≥ 1 dose in an intensive care unit and a CrCl ≤ 50 mL/min or RRT during therapy. Participants were divided into 4 cohorts: moderate impairment (CrCl = 30-50 mL/min), severe impairment (CrCl < 30 mL/min), hemodialysis (HD), or continuous venovenous hemofiltration (CVVH). Outcomes included the incidence of clinically significant bleeding and thromboembolic events. Fondaparinux dose, dosing frequency, and anti-Xa level monitoring are described. Pharmacokinetic modeling was performed to assess drug accumulation. RESULTS: In all, 95 patients met inclusion criteria: 64 (67.4%) with moderate impairment, 10 (10.5%) with severe impairment, 5 (5.3%) with HD, and 16 (16.8%) with CVVH. The median defined daily doses in the moderate, severe, HD, and CVVH cohorts were 2.5, 2.5, 0.9, and 1.9 mg. Anti-Xa monitoring occurred in 19 (20%) patients, although few concentrations were peaks. Clinically significant bleeding occurred in 4 (4.2%) patients. A pharmacokinetic model demonstrated drug accumulation. CONCLUSIONS: Empirical dose adjustments may be prudent in critically ill patients with renal dysfunction; however, the optimal fondaparinux dosage in this population remains unknown. Peak anti-Xa concentrations may help guide therapy.

Assessment of HIV testing among young methamphetamine users in Muse, Northern Shan State, Myanmar.

BACKGROUND: Methamphetamine (MA) use has a strong correlation with risky sexual behaviors, and thus may be triggering the growing HIV epidemic in Myanmar. Although methamphetamine use is a serious public health concern, only a few studies have examined HIV testing among young drug users. This study aimed to examine how predisposing, enabling and need factors affect HIV testing among young MA users. METHODS: A cross-sectional study was conducted from January to March 2013 in Muse city in the Northern Shan State of Myanmar. Using a respondent-driven sampling method, 776 MA users aged 18-24 years were recruited. The main outcome of interest was whether participants had ever been tested for HIV. Descriptive statistics and multivariate logistic regression were applied in this study. RESULTS: Approximately 14.7% of young MA users had ever been tested for HIV. Significant positive predictors of HIV testing included predisposing factors such as being a female MA user, having had higher education, and currently living with one's spouse/sexual partner. Significant enabling factors included being employed and having ever visited NGO clinics or met NGO workers. Significant need factors were having ever been diagnosed with an STI and having ever wanted to receive help to stop drug use. CONCLUSIONS: Predisposing, enabling and need factors were significant contributors affecting uptake of HIV testing among young MA users. Integrating HIV testing into STI treatment programs, alongside general expansion of HIV testing services may be effective in increasing HIV testing uptake among young MA users.

Differential contribution of CBP:CREB binding to corticotropin-releasing hormone expression in the infant and adult hypothalamus.

Corticotropin-releasing hormone (CRH) contributes crucially to the regulation of central and peripheral responses to stress. Because of the importance of a finely tuned stress system, CRH expression is tightly regulated in an organ- and brain region-specific manner. Thus, in the hypothalamus, CRH is constitutively expressed and this expression is further enhanced by stress; however, the underlying regulatory mechanisms are not fully understood. The regulatory region of the crh gene contains several elements, including the cyclic-AMP response element (CRE), and the role of the CRE interaction with the cyclic-AMP response element binding protein (CREB) in CRH expression has been a focus of intensive research. Notably, whereas thousands of genes contain a CRE, the functional regulation of gene expression by the CRE:CREB system is limited to ∼100 genes, and likely requires additional proteins. Here, we investigated the role of a member of the CREB complex, CREB binding protein (CBP), in basal and stress-induced CRH expression during development and in the adult. Using mice with a deficient CREB-binding site on CBP, we found that CBP:CREB interaction is necessary for normal basal CRH expression at the mRNA and protein level in the nine-day-old mouse, prior to onset of functional regulation of hypothalamic CRH expression by glucocorticoids. This interaction, which functions directly on crh or indirectly via regulation of other genes, was no longer required for maintenance of basal CRH expression levels in the adult. However, CBP:CREB binding contributed to stress-induced CRH expression in the adult, enabling rapid CRH synthesis in hypothalamus. CBP:CREB binding deficiency did not disrupt basal corticosterone plasma levels or acute stress-evoked corticosterone release. Because dysregulation of CRH expression occurs in stress-related disorders including depression, a full understanding of the complex regulation of this gene is important in both health and disease.

Emerging roles of epigenetic mechanisms in the enduring effects of early-life stress and experience on learning and memory.

Epigenetic mechanisms are involved in programming gene expression throughout development. In addition, they are key contributors to the processes by which early-life experience fine-tunes the expression levels of key neuronal genes, governing learning and memory throughout life. Here we describe the long-lasting, bi-directional effects of early-life experience on learning and memory. We discuss how enriched postnatal experience enduringly augments spatial learning, and how chronic early-life stress results in persistent and progressive deficits in the structure and function of hippocampal neurons. The existing and emerging roles of epigenetic mechanisms in these fundamental neuroplasticity phenomena are illustrated.