An Assessment of H1N1 Influenza-Associated Acute Respiratory Distress Syndrome Severity after Adjustment for Treatment Characteristics

Pandemic influenza caused significant increases in healthcare utilization across several continents including the use of high-intensity rescue therapies like extracorporeal membrane oxygenation (ECMO) or high-frequency oscillatory ventilation (HFOV). The severity of illness observed with pandemic influenza in 2009 strained healthcare resources. Because lung injury in ARDS can be influenced by daily management and multiple organ failure, we performed a retrospective cohort study to understand the severity of H1N1 associated ARDS after adjustment for treatment. Sixty subjects were identified in our hospital with ARDS from “direct injury” within 24 hours of ICU admission over a three month period. Twenty-three subjects (38.3%) were positive for H1N1 within 72 hours of hospitalization. These cases of H1N1-associated ARDS were compared to non-H1N1 associated ARDS patients. Subjects with H1N1-associated ARDS were younger and more likely to have a higher body mass index (BMI), present more rapidly and have worse oxygenation. Severity of illness (SOFA score) was directly related to worse oxygenation. Management was similar between the two groups on the day of admission and subsequent five days with respect to tidal volumes used, fluid balance and transfusion practices. There was, however, more frequent use of “rescue” therapy like prone ventilation, HFOV or ECMO in H1N1 patients. First morning set tidal volumes and BMI were significantly associated with increased severity of lung injury (Lung injury score, LIS) at presentation and over time while prior prescription of statins was protective. After assessment of the effect of these co-interventions LIS was significantly higher in H1N1 patients. Patients with pandemic influenza-associated ARDS had higher LIS both at presentation and over the course of the first six days of treatment when compared to non-H1N1 associated ARDS controls. The difference in LIS persisted over the duration of observation in patients with H1N1 possibly explaining the increased duration of mechanical ventilation

In-Vitro Activity of Polymyxin B, Rifampicin, Tigecycline Alone and in Combination against Carbapenem-Resistant Acinetobacter baumannii in Singapore

OBJECTIVE: Carbapenem-resistant Acinetobacter baumannii (CR-AB) is an emerging cause of nosocomial infections worldwide. Combination therapy may be the only viable option until new antibiotics become available. The objective of this study is to identify potential antimicrobial combinations against CR-AB isolated from our local hospitals. METHODS: AB isolates from all public hospitals in Singapore were systematically collected between 2006 and 2007. MICs were determined according to CLSI guidelines. All CR-AB isolates were genotyped using a PCR-based method. Clonal relationship was elucidated. Time-kill studies (TKS) were conducted with polymyxin B, rifampicin and tigecycline alone and in combination using clinically relevant (achievable) unbound concentrations. RESULTS: 31 CR AB isolates were identified. They are multidrug-resistant, but are susceptible to polymyxin B. From clonal typing, 8 clonal groups were identified and 11 isolates exhibited clonal diversity. In single TKS, polymyxin B, rifampicin and tigecycline alone did not exhibit bactericidal activity at 24 hours. In combination TKS, polymyxin plus rifampicin, polymyxin B plus tigecycline and tigecycline plus rifampicin exhibited bactericidal killing in 13/31, 9/31 and 7/31 isolates respectively at 24 hours. Within a clonal group, there may be no consensus with the types of antibiotics combinations that could still kill effectively. CONCLUSION: Monotherapy with polymyxin B may not be adequate against polymyxin B susceptible AB isolates. These findings demonstrate that in-vitro synergy of antibiotic combinations in CR AB may be strain dependant. It may guide us in choosing a pre-emptive therapy for CR AB infections and warrants further investigations

Evaluation of the best method to assess antibiotic potentiation by phytochemicals against staphylococcus aureus

The increasing occurrence of bacterial resistance to antibiotics has now reached a critical level. Finding antibiotic coadjuvants capable to inhibit the bacterial resistance mechanisms would be a valuable mid-term solution, until new classes of antibiotics are discovered. Selected plant alkaloids were combined with 5 antibiotics against 10 Staphylococcus aureus strains, including strains expressing distinct efflux pumps and methicillin-resistant S. aureus strains. The efficacy of each combination was assessed using the microdilution checkerboard, time-kill, Etest, and disc diffusion methods. The cytotoxicity of the alkaloids was evaluated in a mouse fibroblast cell line. Potentiation was obtained in 6% of all 190 combinations, especially with the combination of: ciprofloxacin with reserpine (RES), pyrrolidine (PYR), and quinine (QUIN); tetracycline with RES; and erythromycin with PYR. The highest cytotoxicity values were found for QUIN (half maximal inhibitory concentration [IC50] = 25 ± 2.2 mg/L) and theophylline (IC50 = 100 ± 4.7 mg/L).The authors are very grateful to Professor Simon Gibbons (Department of Pharmaceutical and Biological Chemistry, The School of Pharmacy, UCL School of Pharmacy, London) for providing some of the bacterial strains. This work was supported by Operational Programme for Competitiveness Factors - COMPETE and by FCT Portuguese Foundation for Science and Technology through Projects Bioresist - PTDC/EBB-EBI/105085/2008; Phytodisinfectants - PTDC/DTP-SAP/1078/2012 and the PhD grants awarded to Ana Abreu (SFRH/BD/84393/2012) and Anabela Borges (SFRH/BD/63398/2009)

Predisposition of COVID-19 patients to secondary infections: set in stone or subject to change?

Detailed formal protocol with illustrations and extensive bibliography.A recording of the protocol presentation is available on UT Southwestern’s Mediasite. Note: Access to the video is restricted to authorized UT Southwestern users only.UT Southwestern--Internal Medicin

Lung Abscess and Empyema: Review Questions

Choose the single best answer for each question. Questions 1 and 2 refer to the following case. A 56-year-old man presents to the emergency department (ED) complaining of blood-tinged sputum. The patient reports a 15-lb weight loss and productive cough with foul-smelling sputum over the last 2 months. He has had subjective fever and has awakened almost every night drenched in sweat. He drinks 10 beers every day. On physical examination, the patient has a blood pressure of 134/92 mm Hg, heart rate of 102 bpm, respiratory rate of 22 breaths/min, and temperature of 100°F. The patient has gingivitis and digital clubbing, and lung examination reveals coarse inspiratory crackles predominantly in the lower lobe of the right lung. Laboratory testing reveals a leukocyte count of 16,000 cells/µL with 93 % polymorphonuclear neutrophils. Gram stain of a sputum specimen reveals numerous polymorphonuclear leukocytes with a mixture of gram-positive cocci in chains and gram-negative bacilli. Blood culture shows no growth of microorganisms. Chest radiograph is unremarkable, and a computed tomography scan shows a right-sided cavitary lung lesion (Figure 1). 1. What is the most appropriate initial step in the management of this patient

Leprosy Trends in Zambia 1991-2009.

Objective To document leprosy trends in Zambia over the past two decades to ascertain the importance of leprosy as a health problem in Zambia. Methods Retrospective study covering the period 19912009 of routine national leprosy surveillance data, published national programme review reports and desk reviews of in-country TB reports. Results Data reports were available for all the years under study apart from years 2001, 2002 and 2006. The Leprosy case notification rates (CNR) declined from 2.73/10 000 population in 1991 to 0.43/10 000 population in 2009. The general leprosy burden showed a downward trend for both adults and children. Leprosy case burden dropped from approximately 18 000 cases in 1980 to only about 1000 cases in 1996, and by the year 2000, the prevalence rates had fallen to 0.67/10 000 population. There were more multibacillary cases of leprosy than pauci-bacillary cases. Several major gaps in data recording, entry and surveillance were identified. Data on disaggregation by gender, HIV status or geographical origin were not available. Conclusion Whilst Zambia has achieved WHO targets for leprosy control, leprosy prevalence data from Zambia may not reflect real situation because of poor data recording and surveillance. Greater investment into infrastructure and training are required for more accurate surveillance of leprosy in Zambia

Investigation of the first reported outbreak of New Delhi metallo-β-lactamase-1-producing Pseudomonas aeruginosa in Texas

We describe an epidemiologic investigation and successful control measures for the first reported outbreak of blaNDM-1-carrying Pseudomonas aeruginosa in Texas occurring in a veteran with transmission of the same organism and a blaNDM-5-carrying Escherichia coli, respectively, to two roommates and blaNDM-carrying organism/s to a patient cared for by common staff