Serial Procalcitonin Levels Correlate with Microbial Etiology in Hospitalized Patients with Pneumonia

Background

Procalcitonin (PCT) is a biomarker that is finding increasing diagnostic and prognostic utility in lower respiratory infections. It remains unclear, however, whether it can be helpful in predicting the bacterial etiology of pneumonia, with a view to informing antibiotic choice and duration. This study examines the relationship between serial PCT measurements and microbial etiology in patients hospitalized for pneumonia to determine whether changes in PCT levels provide discriminatory information on microbial etiology.

Methods

We performed a subgroup analysis of data from a prospective cohort study of 505 patients admitted to a tertiary care center with findings concerning for pneumonia. Microbial etiology of pneumonia was determined from high quality respiratory samples, blood cultures or other relevant diagnostic tests according to standard protocols. Procalcitonin levels were measured serially during the first four days of hospitalization. We compared procalcitonin levels between different bacterial etiologies over the first four days of admission, using the Mann–Whitney-U test to assess for statistical significance.

Results

Out of 505 patients, the diagnosis of pneumonia was adjudicated in 317, and bacterial etiology determined in 62 cases. The predominant pathogens were Staphylococcus aureus (N = 18), Streptococcus pneumoniae (N = 6), Pseudomonas aeruginosa (N = 11) and Haemophilus influenza (N = 5). Admission levels of PCT were lowest in Pseudomonas infections and highest in pneumococcal infections, though not reaching statistical significance. On hospital days two and three, pneumococcal procalcitonin levels were significantly higher than all other etiologies, but on day four, there was no statistically significant difference in PCT values for different microbial etiologies.

Conclusion

Serial procalcitonin levels during the early course of bacterial pneumonia reveal a difference between pneumococcal and other bacterial etiologies, and may have an adjunct role in guiding antibiotic choice and duration.

Disclosures

All authors: No reported disclosures.

Corticosteroid Use Following the Onset of Invasive Aspergillosis is Associated with Increased Mortality: A Propensity Score-Matched Study

Background

The safety of corticosteroid use (CSU) during active infection is controversial. In the invasive aspergillosis (IA) literature, CSU is typically defined using the time period prior to IA onset. Clinicians caring for patients with IA are unable to control prior CSU. The more clinically relevant question is whether CSU after IA onset is harmful.

Methods

Patients hospitalized at our institution from 2004 to 2014 with IA were retrospectively identified. CSU, defined as the average daily prednisone equivalent dose during the 7-day period following IA onset, was calculated for each patient. A CSU cut-off of 7.5mg was used to assign patients to treatment (>7.5mg) or control (<7.5mg, including no CSU) groups. A propensity score (PS) was generated to predict group assignment. Nearest neighbor matching was performed with a caliper width of 0.2. A Cox proportional hazards model was used to assess survival 6 weeks after IA onset.

Results

PS matching generated 61 matched pairs (122 patients). Baseline characteristics did not differ significantly between groups (Table). CSU was associated with increased mortality (PS adjusted hazard ratio [HR] 2.91, 95% CI 1.32–6.40). In the CSU group, a trend towards lower mortality was noted if corticosteroid dose was tapered to 7.5mg/day (HR 0.68, 95% CI 0.46–1.02).

Conclusion

CSU after IA onset is associated with increased mortality. In IA patients with CSU, efforts to reduce corticosteroid dose may be beneficial.

Disclosures

All authors: No reported disclosures.

Posterior Reversible Encephalopathy Syndrome : A Rare Cause of Sudden Onset Vision Loss in Pregnancy

Posterior Reversible Encephalopathy Syndrome (PRES) is a very rare cause of sudden onset vision loss in pregnancy. There are only few case reports in literature. It is characterized by headache, seizures, altered mental status and visual deficits ranging from visual neglect to cortical blindness. Here a case if PRES has been reported with discussion on its pathophysiology. NJOG 2011 Nov-Dec; 6 (2): 51-52 DOI: http://dx.doi.org/10.3126/njog.v6i2.6759

Impact of Unsafe Abortion: A Case Report

Legalisation of abortion is a necessary but insufficient step towards improving women’s health, if it is not supported by a strong back-up of skilled providers, adequate facilities and easy access. We report a case of a 20-year old female, who presented with uterine, vaginal and rectal perforation with macerated fetus in the abdominal cavity with severe sepsis after an attempted unsafe abortion. NJOG 2011 Nov-Dec; 6 (2): 47-48 DOI: http://dx.doi.org/10.3126/njog.v6i2.6757

Dectin-1 controls maturation of fungal phagosomes (55.1)

Dectin-1 recognizes the fungal wall carbohydrate, β-1,3-D-glucan. Defects in Dectin-1 have been isolated in patients suffering from recurrent Candidal infections demonstrating the essential role of carbohydrate recognition in eliciting protective immunity. In the following work, we sought to characterize the intracellular steps following β-1,3-D-glucan phagocytosis by macrophages. In previous studies, we described a fungal-like particle (FLP) consisting of a polystyrene bead platform covalently conjugated to β-1,3-D-glucan thus mimicking the geometry and surface of fungal pathogens. Using a RAW cell line expressing GFP-Dectin-1, we show that there is translocation of Dectin-1 from the surface to the FLP-containing phagosome which is eliminated by 2h. In order to explore the contribution of Dectin-1-specific intracellular signaling towards the off-rate, a TYR to PHE substitution was introduced within the ITAM-like motif of the cytoplasmic domain of Dectin-1 (ΔY3). GFP-Dectin-1-ΔY3 showed prolonged retention to the phagosome when compared to WT Dectin-1. We next explored subsequent phagolysosomal maturation milestones. Interestingly, phagosomes with intense Dectin-1-ΔY3 did not acidify or recruit LAMP-1 suggesting phagolysosomal maturation blockade. Using Candida albicans, similar deficits in phagosomal maturation were seen with Dectin-1-ΔY3-positive Candida containing phagosomes. These data suggest novel role for Dectin-1 as a controller of fungal phagosome maturation.

Use of Fungal-like Particles to probe Dectin-1 Responses in Innate Immunity (58.12)

The presence of multiple types of carbohydrate moieties on fungal cell walls prohibits elucidation of the exact immunological response to pathogen-derived carbohydrate epitopes. To dissect the immunological mechanisms used to recognize pathogens, a system of “fungal like particles” was developed that consisted of polymer beads, which mimicked the three dimensional shape of the fungus, coated covalently with purified b-1,3-glucan (BG) derived from S. cerevisiae. The morphology of the BG layer was examined by immunofluorescence, flow cytometery, and immuno-transmission electron microscopy. The covalent linkages of the BG to the polystyrene surface were stable after subjecting the beads to detergents. By pre-treating BG beads with laminarinase the reactivity of the anti-BG antibody was abrogated in comparison to treatment with proteinase K indicating that the coating of these beads was predominantly BG. TNF-a was also measured by stimulating bone-marrow derived macrophages with the BG beads and showed a dose dependent response. Finally, BG beads were incubated with GFP-Dectin-1 expressing macrophages and imaged using confocal microscopy. BG beads were taken up within minutes and retained Dectin-1, the major receptor for BG, to the phagosome as compared to uncoated beads. This data describes a unique fungal-like particle system that will permit immunologists to probe the critical steps in early recognition of pathogen-derived fungal carbohydrate antigens by innate immune cells.

Dectin-1 Signaling Recruits Elements of the Autophagic Machinery to Candida albicans-containing Phagosomes (55.2)

A classic hallmark in the autophagic process is the reversible conjugation of LC3 to the autophagosomal membrane. Autophagy has been shown to target pathogens that reside in the cytosol or within autophagosomes for lysosomal degradation. Therefore, components of the autophagy pathway can participate in the effective elimination of viruses, bacteria, and parasites, though their role in fungal immunity is poorly understood. We show that activation of Dectin-1 by its ligand β-1,3-glucan leads to recruitment of LC3 to the phagosome and describe multiple intermediate signaling steps. The cytoplasmic tail of Dectin-1 contains an immunoreceptor tyrosine-based activation (ITAM)-like motif which is phosphorylated in response to binding of β-1,3-glucan, leading to relocation from the cell surface to the phagosome. We show that Dectin-1 activation by intact fungal pathogens or by chemically defined ligands leads to LC3 recruitment to the phagosomal membrane. Mutation of the tyrosine phosphorylation site in Dectin-1 abolished LC3 recruitment, suggesting the involvement of spleen tyrosine kinase (Syk) in this subcellular redistribution of LC3. Likewise, impairment of ROS generation by knockout of NADPH oxidase (NCF4) downstream of Syk inhibited LC3 recruitment to the phagosome, whereas knockout of Card9 did not affect LC3 recruitment. These observations suggest a previously unobserved signaling pathway connects Dectin-1 to the autophagic machinery via Syk signaling and ROS generation.

Laparoscopic kidney transplantation: an initial experience

Laparoscopic donor nephrectomy has the advantages of less pain, early ambulation and shorter hospitalization compared to open donor nephrectomy. Kidney recipient surgery is, however, traditionally performed by open surgery. Our aim was to study feasibility and safety of laparoscopic kidney transplantation (LKT). After permission from Internal Review Board, LKT was performed in four patients. All kidneys were procured from deceased donors. Left kidney was used for LKT and transplanted in left iliac fossa while right kidney was used for standard open kidney transplantation (OKT). All transplantation procedures were performed successfully. Cold ischemia time varied between 4 h and 14 h. For LKT, mean time for anastomosis was 65 (range 62-72) min, mean operative time was 3.97 (range 3.5-5) h, mean blood loss was 131.25 mL (range 45-350) mL. Mean wound length was 7 cm in LKT group and 18.4 cm in OKT group. Delayed graft function was observed in one patient in each group. One patient was lost in OKT group due to posttransplant bacterial meningitis. At 6 months, both groups have comparable value of serum creatinine. In conclusion, LKT is technically feasible and safe. Long term outcome needs to be evaluated in a larger study.

Long-term donor outcomes after living kidney donation

Kidney transplant is the first choice of treatment for end-stage renal failure. The issue of long-term donor safety again has been raised by recent increases in living-donor kidney transplants worldwide, relaxation of donor selection criteria, and the introduction of new surgical techniques. In this review, we collated the results of various studies to discuss the effects of donation on the quality of life of donors, encompassing their physical, mental, and social well-being. We found that the health risks donors face are minimal in the long term with respect to renal function, hypertension, and life span. Furthermore, donors scored higher in quality of life studies than did persons in the general population. Despite these findings, there is a clear need to monitor the minimal risks with long-term follow-up of donors to promptly recognize and treat any negative health effects. Such data from thorough follow-up studies also would provide accurate information on longterm donor health and improve the safe expansion of donor selection criteria.

Proactive treatment of atopic dermatitis in adults with 0.1% tacrolimus ointment

BACKGROUND

Long-term treatment for atopic dermatitis (AD) using low dose, intermittent, topical anti-inflammatory agents may control acute disease and prevent relapses. This 12-month, European, multicentre, randomized study investigated whether the proactive use of 0.1% tacrolimus ointment applied twice weekly can keep AD in remission and reduce the incidence of disease exacerbations (DE).

METHODS

During the initial open-label period, 257 adults with AD applied 0.1% tacrolimus ointment twice daily (b.i.d.) for up to 6 weeks to affected areas. When an Investigator Global Assessment (IGA) score of <or=2 was achieved, the patient entered the disease control period (DCP) and was randomized to either proactive tacrolimus (n = 116) or vehicle ointment (n = 108) twice weekly for 12 months. Exacerbations were treated with 0.1% tacrolimus ointment b.i.d. until an IGA <or=2 was regained, then randomized treatment was restarted. The primary endpoint was the number of DEs during the DCP that required a substantial therapeutic intervention.

RESULTS

Proactive tacrolimus 0.1% ointment application significantly reduced the number of DEs requiring substantial therapeutic intervention (median difference 2; P < 0.001; Wilcoxon rank sum test), the percentage of DE treatment days (median difference: 15.2%; P < 0.001; Wilcoxon rank sum test) and increased the time to first DE (median 142 vs 15 days; P < 0.001; stratified log-rank test). The adverse event profile was similar for the two treatment approaches.

CONCLUSION

A 12-month, twice weekly proactive tacrolimus ointment application was an effective treatment in most study patients which prevented, delayed and reduced the occurrence of AD exacerbations

Proactive treatment of atopic dermatitis in adults with 0.1% tacrolimus ointment

BACKGROUND

Long-term treatment for atopic dermatitis (AD) using low dose, intermittent, topical anti-inflammatory agents may control acute disease and prevent relapses. This 12-month, European, multicentre, randomized study investigated whether the proactive use of 0.1% tacrolimus ointment applied twice weekly can keep AD in remission and reduce the incidence of disease exacerbations (DE).

METHODS

During the initial open-label period, 257 adults with AD applied 0.1% tacrolimus ointment twice daily (b.i.d.) for up to 6 weeks to affected areas. When an Investigator Global Assessment (IGA) score of < or =2 was achieved, the patient entered the disease control period (DCP) and was randomized to either proactive tacrolimus (n = 116) or vehicle ointment (n = 108) twice weekly for 12 months. Exacerbations were treated with 0.1% tacrolimus ointment b.i.d. until an IGA < or =2 was regained, then randomized treatment was restarted. The primary endpoint was the number of DEs during the DCP that required a substantial therapeutic intervention.

RESULTS

Proactive tacrolimus 0.1% ointment application significantly reduced the number of DEs requiring substantial therapeutic intervention (median difference 2; P < 0.001; Wilcoxon rank sum test), the percentage of DE treatment days (median difference: 15.2%; P < 0.001; Wilcoxon rank sum test) and increased the time to first DE (median 142 vs 15 days; P < 0.001; stratified log-rank test). The adverse event profile was similar for the two treatment approaches.

CONCLUSION

A 12-month, twice weekly proactive tacrolimus ointment application was an effective treatment in most study patients which prevented, delayed and reduced the occurrence of AD exacerbations.

The biological monitoring of prenatal exposure to methylmercury

Several biological media have been used as indicators of the fetal body burden of methylmercury and the levels in the primary target tissue, the developing brain. These media include maternal hair and blood. The relative merits of these media will be considered both with regard to current knowledge of the physiology of mercury disposition in the body and also the practicality of field application with respect to sample, collection, transport, storage and processing.

Overexpression of the Axl tyrosine kinase receptor in cutaneous SCC-derived cell lines and tumours

The molecular mechanisms that underlie the development of squamous cell skin cancers (SSC) are poorly understood. We have used oligonucleotide microarrays to compare the differences in cellular gene expression between a series of keratinocyte cell that mimic disease progression with the aim of identifying genes that may potentially contribute towards squamous cell carcinoma (SCC) progression in vivo, and in particular to identify markers that may serve as potential therapeutic targets for SCC treatment. Gene expression differences were corroborated by polymerase chain reaction and Western blotting. We identified Axl, a receptor tyrosine kinase with transforming potential that has also been shown to have a role in cell survival, adhesion and chemotaxis, was upregulated in vitro in SCC-derived cells compared to premalignant cells. Extending the investigation to tumour biopsies showed that the Axl protein was overexpressed in vivo in a series of SCCs.

Immunization with f-Met peptides induces immune reactivity against Mycobacterium tuberculosis

OBJECTIVE

To determine whether synthetic peptides containing an amino terminal formyl-methionine residue and corresponding to the sequence of several proteins produced by Mycobacterium tuberculosis, would elicit an immune response in mice.

DESIGN

Peptides corresponding to the amino termini of 8 M. tuberculosis proteins and initiating with formyl methionine residues were synthesized. The ability of these peptides to bind to the mouse non-classical MHC class I molecule H-2M3a was determined by flow microfluorimetry. These peptides were used to pulse dendritic cells that were then injected into normal mice. These mice were subsequently challenged with aerosolized M. tuberculosis and, 30 days later, the number of viable bacteria in the lungs was determined.

RESULTS

Four of the 8 synthetic peptides bound to H-2M3a and stabilized its expression on the cell surface. Injection of mice with dendritic cells pulsed with H-2M3a binding peptides elicited non-MHC restricted cytotoxic T lymphocytes that killed peptide pulsed target cells and macrophages infected with M. tuberculosis. Immunization of mice with syngeneic dendritic cells pulsed in vitro with 2 of these peptides led to retardation of the growth of M. tuberculosis following aerosol challenge.

CONCLUSION

Peptides that bind to non-polymorphic class I molecules can elicit immune reactivity directed towards M. tuberculosis.

Severe retinopathy of prematurity and its association with different rates of survival in infants of less than 1251 g birth weight

BACKGROUND

There is controversy over whether improved survival of preterm infants has resulted in a higher incidence of severe (grade 3 or greater) retinopathy of prematurity (ROP).

AIM

To compare survival rates and rates of > or = stage 3 ROP-that is, with a high risk of sequelae-in preterm infants in five English cities where, anecdotally, the incidence of ROP is reported to show considerable variation.

METHODS

All infants of birth weight < 1500 g and or gestational age < 32 weeks, born in 1994 in one of the cities or transferred in within 48 hours, were studied. The populations were adjusted for case mix variation using CRIB (clinical risk index for babies, a disease severity scoring system). The incidence of severe ROP, the actual death rate, and that adjusted for disease severity were determined.

RESULTS

The rate of severe ROP per 1000 births was higher in city 1 than in all the other cities. This increase in comparison with city 2 and city 4 was significant (city 1, 167 (95% confidence interval (CI) 96 to 260); city 2, 24 (6 to 59); city 4, 16 (1 to 84)). A significant difference was not seen between city 1 and cities 3 (23 (1 to 120)) and 5 (74 (21 to 79)). The relative risk of developing severe ROP in city 1 compared with all the other cities was 5.5 (2.5 to 11.9). The actual death rate per 1000 births in city 1 was significantly lower than that predicted by modelling death against CRIB score (city 1: actual 270; predicted 385 (95% CI 339 to 431)). In contrast, the other cities had actual death rates as predicted, or worse than predicted, by CRIB.

INTERPRETATION

A significantly higher incidence of severe ROP was identified in one of the five cities studied. Variation in survival rates among high risk infants may explain this observation.

Should paediatric intensive care be centralised? Trent versus Victoria

BACKGROUND

The mortality rate is lower among children admitted to specialist paediatric intensive care units (ICUs) than among those admitted to mixed adult and paediatric units in non-tertiary hospitals. In the UK, however, few children receive intensive care in specialist paediatric units. We compared the ICU mortality rate in children from the area the Trent Health Authority, UK, with the rate in children from Victoria, Australia, where paediatric intensive care is highly centralised.

METHODS

We studied all children under 16 years of age from Trent and Victoria who received intensive care between April 1, 1994, and March 31, 1995. Children younger than 1 month were excluded unless they had cardiac disorders. We developed a logistic regression model that used information gathered at the time of admission to ICU to adjust for risk of mortality.

FINDINGS

The rates of admission of children to intensive care were similar for Trent and Victoria (1.22 and 1.18 per 1000 children per year), but the mean duration of an ICU stay was 3.93 days for Trent children compared with 2.14 days for children from Victoria. 74 (7.3%) of the 1014 children from Trent died, compared with 60 (5.0%) of the 1194 children from Victoria. With adjustment for severity of illness at the time of admission to ICU, the odds ratio for the risk of death for Trent versus Victoria was 2.09 (95% CI 1.37-3.19, p < 0.0005). There were 31.7 (14.0-50.4) excess deaths in Trent children, which is equivalent to 42.8% of the deaths in ICU, and 11.1% of all deaths in children between the ages of 1 month and 16 years in Trent.

INTERPRETATION

If Trent is representative of the whole country, there are 453 (200-720) excess deaths a year in the UK that are probably due to suboptimal results from paediatric intensive care. If the ratio of paediatric ICUs to children were the same in the UK as in Victoria, there would be only 12 paediatric ICUs in the country. Our findings suggest that substantial reductions in mortality could be achieved if every UK child who needed endotracheal intubation for more than 12-24 h were admitted to one of 12 large specialist paediatric ICUs.