Impact of delays to incubation and storage temperature on blood culture results: a multi-centre study

Abstract Background Blood cultures are one of the most important tests performed by microbiology laboratories. Many hospitals, particularly in low and middle-income countries, lack either microbiology services or staff to provide 24 h services resulting in delays to blood culture incubation. There is insufficient guidance on how to transport/store blood cultures if delays before incubation are unavoidable, particularly if ambient temperatures are high. This study set out to address this knowledge gap. Methods In three South East Asian countries, four different blood culture systems (two manual and two automated) were used to test blood cultures spiked with five common bacterial pathogens. Prior to incubation the spiked blood culture bottles were stored at different temperatures (25 °C, in a cool-box at ambient temperature, or at 40 °C) for different lengths of time (0 h, 6 h, 12 h or 24 h). The impacts of these different storage conditions on positive blood culture yield and on time to positivity were examined. Results There was no significant loss in yield when blood cultures were stored < 24 h at 25 °C, however, storage for 24 h at 40 °C decreased yields and longer storage times increased times to detection. Conclusion Blood cultures should be incubated with minimal delay to maximize pathogen recovery and timely result reporting, however, this study provides some reassurance that unavoidable delays can be managed to minimize negative impacts. If delays to incubation ≥ 12 h are unavoidable, transportation at a temperature not exceeding 25 °C, and blind sub-cultures prior to incubation should be considered.

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Changes of Physicochemical Properties of Starch Syrups Recommended for Winter Feeding of Honeybees during Storage

Agriculture ◽

10.3390/agriculture11040374 ◽

2021 ◽

Vol 11 (4) ◽

pp. 374

Author(s):

Teresa Szczęsna ◽

Ewa Waś ◽

Piotr Semkiw ◽

Piotr Skubida ◽

Katarzyna Jaśkiewicz ◽

...

Keyword(s):

Chemical Composition ◽

Physicochemical Properties ◽

Physicochemical Parameters ◽

Storage Temperature ◽

Storage Conditions ◽

Different Temperatures ◽

And Storage ◽

Bee Colonies ◽

Temperature Time ◽

Winter Feeding

The aim of this study was to determine the influence of storage temperature and time on physicochemical parameters of starch syrups recommended for the winter feeding of bee colonies. The studies included commercially available three starch syrups and an inverted saccharose syrup that were stored at different temperatures: ca. 20 °C, 10–14 °C, and ca. 4 °C. Physicochemical parameters of fresh syrups (immediately after purchase) and syrups after 3, 6, 9, 12, 15, 18, 21, and 24 months of storage at the abovementioned temperatures were measured. It was observed that the rate of unfavorable changes in chemical composition of starch syrups and the inverted saccharose syrup, mainly the changes in the 5-hydroxymethylfurfural (HMF) content, depended on the type of a syrup and storage conditions (temperature, time). Properties of tested starch syrups intended for winter feeding of bees stored at ca. 20 °C maintained unchanged for up to 6 months, whereas the same syrups stored at lower temperatures (10–14 °C) maintained unchanged physicochemical parameters for about 12 months. In higher temperatures, the HMF content increased. To date, the influence of this compound on bees has not been thoroughly investigated.

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Insufficient Stability of Clavulanic Acid in Widely Used Child-Appropriate Formulations

Antibiotics ◽

10.3390/antibiotics10020225 ◽

2021 ◽

Vol 10 (2) ◽

pp. 225

Author(s):

Ines Mack ◽

Mike Sharland ◽

Janneke M. Brussee ◽

Sophia Rehm ◽

Katharina Rentsch ◽

...

Keyword(s):

Ambient Temperature ◽

Clavulanic Acid ◽

Storage Conditions ◽

Essential Medicines ◽

Active Components ◽

Middle Income ◽

Ambient Temperatures ◽

Essential Medicines List ◽

Dispersible Tablets ◽

The Stability

Amoxicillin-clavulanic acid (AMC) belongs to the WHO Essential Medicines List for children, but for optimal antimicrobial effectiveness, reconstituted dry powder suspensions need to be stored in a refrigerated environment. Many patients in low- and middle-income countries who are sold AMC suspensions would be expected not to keep to the specified storage conditions. We aimed to assess the stability of both ingredients in liquid formulations and dispersible tablets, combined with nationally representative data on access to appropriate storage. Degradation of amoxicillin (AMX) and clavulanic-acid (CLA) was measured in suspensions and dispersible tablets commercially available in Switzerland at different ambient temperatures (8 °C vs. 28 °C over 7 days, and 23 °C vs. 28 °C over 24 h, respectively). Data on access to refrigeration and electricity were assessed from the USAID-funded Demographic and Health Survey program. In suspensions, CLA degraded to a maximum of 12.9% (95% CI −55.7%, +29.9%) at 8°C and 72.3% (95% CI −82.8%, −61.8%) at a 28 °C ambient temperature during an observation period of 7 days. Dispersible tablets were observed during 24 h and CLA degraded to 15.4% (95% CI −51.9%, +21.2%) at 23 °C and 21.7% (−28.2%, −15.1%) at a 28 °C ambient temperature. There is relevant degradation of CLA in suspensions during a 7-day course. To overcome the stability challenges for all active components, durable child-appropriate formulations are needed. Until then, prescribers of AMC suspensions or pharmacists who sell the drug need to create awareness for the importance of proper storage conditions regarding effectiveness of both antibiotics and this recommendation should be reflected in the WHO Essential Medicines List for children.

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847. The Effect of Antimicrobial Administration on Blood Culture Positivity in Patients with Severe Manifestations of Sepsis

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz359.032 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S15-S16

Author(s):

Matthew P Cheng ◽

Robert Stenstrom ◽

Katryn Paquette ◽

Sarah Stabler ◽

Murtaza Akhter ◽

...

Keyword(s):

Blood Culture ◽

Antimicrobial Therapy ◽

Diagnostic Yield ◽

The United States ◽

Blood Cultures ◽

Microbial Pathogens ◽

Absolute Difference ◽

Recovery Rates ◽

Pathogen Recovery ◽

Antimicrobial Administration

Abstract Background Current guidelines recommend obtaining blood cultures prior to antimicrobial therapy in patients with sepsis. Administering antimicrobials immediately without waiting for blood cultures could potentially decrease time to treatment and improve outcomes, but it is unclear the degree to which this strategy impacts diagnostic yield. Methods We performed a patient-level, single-arm, diagnostic trial. Seven urban emergency departments affiliated with academic medical centers across Canada and the United States participated in the study. Adults ≥18 years of age presenting to the emergency department with evidence of severe manifestations of sepsis, including a systolic blood pressure <90 mmHg and/or a serum lactate ≥4 mmol/L were included. Study participants had 2 sets of blood cultures drawn prior to and immediately following antimicrobial administration. The primary outcome was the difference in blood culture pathogen recovery rates before and after administration of antimicrobial therapy. Results Of the 3,164 participants screened, 325 were included in the study (mean age, 65.6 years; 63.0% men) and had repeat blood cultures drawn after the initiation of antimicrobial therapy (median time of 70 minutes, IQR 50 to 110 minutes). Pre-antimicrobial blood cultures were positive for one or more microbial pathogens in 102/325 (31.4%) patients. Fifty-four participants (52.9%) had matching blood culture results after initiation of antimicrobial treatment. The absolute difference in pathogen recovery rates was 14.5% ([95% CI 8.0 to 21.0%]; P < 0.0001) between pre- and post-antimicrobial blood cultures. Results were consistent in an analysis of the per-protocol population (absolute difference, 13.3% [95% CI 6.1 to 20.4%]; P < 0.0001). Including the results of other microbiological cultures done as part of routine care, microbial pathogens were recovered in 69 of 102 (67.7%) participants (absolute difference, 10.2% [95% CI 3.4 to 16.8%]; P < 0.0001). Conclusion Among patients with severe manifestations of sepsis, the administration of empiric antimicrobial therapy significantly reduces the yield of pathogen recovery when blood cultures are drawn shortly after treatment initiation. Disclosures All Authors: No reported Disclosures.

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Effect of storage temperature on Streptococcus mutans viability

Revista de Odontologia da UNESP ◽

10.1590/1807-2577.08317 ◽

2018 ◽

Vol 47 (2) ◽

pp. 74-78

Author(s):

Ana Lídia Soares COTA ◽

Ronaldo Gomes ALVIM

Keyword(s):

Streptococcus Mutans ◽

Storage Temperature ◽

Storage Conditions ◽

Descriptive Statistics ◽

Bacterial Isolates ◽

Future Studies ◽

Long Period ◽

Different Temperatures ◽

Almost All ◽

Microbiological Research

Abstract Introduction Proper storage conditions and maintenance of viable biological material plays an important role in microbiological research, allowing for the opportunity to conduct future studies. Objective To evaluate the viability of Streptococcus mutans strains that were previously grown and stored under different temperatures for approximately eight years. Material and method In this study, we evaluated 393 bacterial isolates that were stored in a freezer at -80°C (G1) and 200 isolates stored in a freezer at -20°C (G2). Aliquots of each sample were plated on blood agar and mitis-salivarius bacitracin sucrose agar-solidified medium. After incubating under microaerophilic conditions in an incubator at 37°C for 72 hours, the presence, morphology and purity of bacterial growth was observed. The data were analyzed by means of descriptive statistics. Result Microbial viability was observed in almost all samples (99.7%) in G1, whereas all isolates stored at -20°C were considered inviable. Conclusion The viability of S. mutans is influenced by the storage temperature of the samples, and the strains remain viable when stored under ideal temperature conditions (-80°C), even when stored for a long period of time.

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Influence of storage time and temperature on the activity of urease

Bulgarian Chemical Communications ◽

10.34049/bcc.51.2.4536 ◽

2019 ◽

Vol 51 (2) ◽

pp. 159-163

Author(s):

B. Alev ◽

S. Tunali ◽

R. Yanardag ◽

A. Yarat

Keyword(s):

Room Temperature ◽

Storage Time ◽

Urease Activity ◽

Storage Temperature ◽

Practical Importance ◽

Storage Conditions ◽

Relative Activity ◽

Significant Loss ◽

Long Term Storage ◽

Activity Measurements

Enzymes are made of protein, that is why they are sensitive molecules and are affected by storage conditions. A small change in enzyme activity during storage may cause a big error in analysis results. The aim of the study was to evaluate the effects of storage time and temperature on urease activity. Urease solutions were prepared at different activities (from 100 to 2000 U/mL) and stored at room temperature, in the refrigerator (4°C), and in the deep freezer (-18°C and -80°C). Activity measurements were made at regular intervals until 28 days by the modified Weatherburn method. The relative activities of 100-1000 U/mL urease solutions stored at room temperature, 4, -18 or -80°C were 75% and below after 4 days. Twenty-eight days later, for 2000 U/mL urease solutions, only at room temperature, the relative activity was reduced to 37%, while at 4, -18 or -80°C, the relative activities were above 80%. Since urease can be maintained at 4°C for 28 days without significant loss of activity, it has practical importance. Low-activity urease solutions (such as 100-1000 U/mL) should not be stored at -18 or -80°C for short or long term storage, they should be stored at 4°C only for one day. Keywords: Urease activity, storage time, storage temperature

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Color change of bottled white wines as a quality indicator

OENO One ◽

10.20870/oeno-one.2020.54.3.3367 ◽

2020 ◽

Vol 54 (3) ◽

pp. 543-551

Author(s):

Antonios Kanavouras ◽

Frank Coutelieris ◽

Eleni Karanika ◽

Yorgos Kotseridis ◽

Stamatina Kallithraka

Keyword(s):

Storage Temperature ◽

Color Change ◽

Colour Change ◽

Storage Conditions ◽

White Wine ◽

Grape Variety ◽

White Wines ◽

Root Cause ◽

Different Temperatures ◽

One Year

Aim: The present work aimed to estimate the probability of bottled white wine exhibiting acceptable colour change during a certain predefined time using a predictive model based on a descriptive mathematically expressed theory.Materials and methods: Nine mono-varietal Greek white wines (produced by three varieties) were bottled and stored at two different temperatures (20 and 30 °C). Their absorbance at 420 nm (A420) was recorded every three months for 12 months. Results were processed by applying the root cause analysis versus storage conditions. Furthermore, a predictive mathematical model was adapted to the experimental data based on the probability of the product showing browning-index values higher than a specific threshold during its shelf life.Results: As expected, the absorbance at 420 nm increased with time, while the elevated storage temperature had a significant effect on colour alteration. The browning rate was dependent on grape variety. When storage temperature was 20 °C, a lower A420 increase was observed for Sauvignon blanc wine, while at 30 °C, browning was higher. Assyrtiko wines were more resistant to colour change at both temperatures. The probability of a bottled product maintaining an acceptable colour change by the end of one year, was used as a measure of its quality. A very successful fit was achieved between mathematical and experimentally obtained data for shelf life predictions.Significance and impact of the study: The modelling of the experimental results, as well as the exploitation of this fitting to make predictions independently of the specific results, indicate that storage temperature will potentially impact the colour of wines over time, depending on the evolution of the absorbance values at 420 nm. For the wine sector, the selection of the appropriate storage conditions for a given grape variety is an important factor to take into consideration.

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Effects of Storage Duration on Biodiesel Properties Derived from Waste Cooking Oil

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.554.494 ◽

2014 ◽

Vol 554 ◽

pp. 494-499 ◽

Cited By ~ 19

Author(s):

Amir Khalid ◽

Norazwan Azman ◽

Hanis Zakaria ◽

Bukhari Manshoor ◽

Izzuddin Zaman ◽

...

Keyword(s):

Water Content ◽

Fossil Fuels ◽

Storage Temperature ◽

Acid Value ◽

Waste Cooking Oil ◽

Storage Conditions ◽

Storage Duration ◽

Oil Reserves ◽

Cooking Oil ◽

Different Temperatures

The reduction of world oil reserves fossil fuels and increasing environmental concerns significantly influences the popularity of biodiesel as an alternative diesel. This research investigates the effects of storage duration of variant blending waste cooking oil ratio under different storage temperature on fuel properties. The biodiesel samples were stored at different temperatures and were monitored at regular interval over a period of 70 days. Blending of biodiesel was varied from 5vol % (WCO5) ~15vol% (WCO15) and storage temperature from 24°C~35°C. These samples were monitored on a weekly and the effects of storage conditions on properties of biodiesel such as density, kinematics viscosity, acid value, water content and flash point of biodiesel were discussed in detail. The observation of biodiesel shows that the increasing of storage duration of biodiesel derived from waste cocking oil influences to the increasing of density, kinematics viscosity, acid value and water content.

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Quality Changes during Storage of Burkina (a Millet and Milk-based) Drink

Asian Food Science Journal ◽

10.9734/afsj/2020/v15i230146 ◽

2020 ◽

pp. 1-5

Author(s):

Ampofo-Asiama Jerry ◽

Mamudu Hafusatu ◽

Helen Oluchi Emeruwa ◽

Owusu Fokuo Kant ◽

Quaye Bright

Keyword(s):

Phenolic Content ◽

Storage Temperature ◽

Energy Content ◽

Titratable Acidity ◽

Storage Conditions ◽

High Energy ◽

Small Scale ◽

Content Quality ◽

Different Temperatures

Burkina, a drink prepared from millet and milk, is gaining economic attention in Ghana due to its perceived nutritious nature and high energy content. The drink which is produced on a small-scale is usually vended without proper control of storage conditions leading to rapid loss of quality. The objective of this study was to investigate the effect of storing burkina at different temperatures (4 and 30°C) on the microbial and physicochemical (pH, titratable acidity, brix and phenolic content) quality of the drink. The pH, titratable acidity, brix and phenolic content of freshly prepared burkina were 3.65, 0.49%, 2.05 and 0.26 mg GAE/100 g, respectively. Although, changes were observed, storage temperature did not have a significant effect on the physicochemical quality of burkina. The initial load of aerobic mesophiles, lactic acid bacteria, Enterobacteriaceae, and yeast and moulds in the freshly prepared Burkina were 6.45, 5.49, 2.58 and 4.45 log cfu/mL, respectively. Storage at the higher temperature resulted in an increased microbial load within 48 h, leading to faster spoilage, with only marginal increases observed at the lower storage temperature.

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EFFECTS OF STORAGE CONDITIONS AND PRESENCE OF FRUITING BRACTS ON THE GERMINATION OF ATRIPLEX HALIMUS AND SALSOLA VERMICULATA

Experimental Agriculture ◽

10.1017/s0014479797000021 ◽

1997 ◽

Vol 33 (2) ◽

pp. 149-155 ◽

Cited By ~ 16

Author(s):

A. E. OSMAN ◽

F. GHASSALI

Keyword(s):

Seed Germination ◽

Cold Storage ◽

North Africa ◽

Room Temperature ◽

Storage Temperature ◽

Seed Storage ◽

Storage Conditions ◽

Shrub Species ◽

Atriplex Halimus ◽

Different Temperatures

Two shrub species, Atriplex halimus L. and Salsola vermiculata L., are considered useful for rehabilitation of degraded rangelands in west Asia and north Africa. They can be established from direct seeding and are capable of self-sowing. In this study, seed storage at different temperatures and the influence of fruiting bracts on seed germination were examined for the two species during two seasons. Fruits (utricles) were stored at 20–22°C (room temperature), 0°C or −22°C. Germination tests were carried out after 33, 56, 90, 152, 272 and 397 d in storage in the first season and after 44, 76, 104, 170, 288 and 412 d in the second season. Seeds were germinated in their fruiting bracts or after bract removal. Bract removal significantly improved seed germination of both shrubs regardless of storage temperature. For S. vermiculata the increase in germination was in the range of 1.3- to 14.7-fold compared with values for the intact fruit in Season 1 and 0.5 to 3.8 in Season 2. Similarly the ranges for A. halimus were 0.5- to 4.2-fold and 0.7- to 5.3-fold in the two seasons respectively. The effect of cold storage was greater on Salsola than on Atriplex. The reduction of the storage temperature from 21°C to 0°C and −22°C increased the longevity of S. vermiculata seeds by 2.8–46.6 times in Season 1 and by 2.9–2.6 times in Season 2. There was little or no effect on the longevity of A. halimus. A leachate prepared by soaking fruiting bracts from S. vermiculata significantly depressed germination (p < 0.01), the effect being greater on Salsola seeds (20% reduction) than on Atriplex seeds (8% reduction). A leachate from A. halimus produced a slight but non-significant reduction in germination.

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Influence of Alcohol Content and Storage Conditions on the Physicochemical Stability of Spirit Drinks

Foods ◽

10.3390/foods9091264 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1264

Author(s):

Mateusz Różański ◽

Katarzyna Pielech-Przybylska ◽

Maria Balcerek

Keyword(s):

Volatile Compounds ◽

Storage Temperature ◽

Storage Conditions ◽

Deionized Water ◽

Higher Alcohols ◽

Alcohol Content ◽

C Storage ◽

Physicochemical Stability ◽

Different Temperatures ◽

And Storage

The purpose of this study was to investigate the effects of alcohol by volume (ABV) and storage temperature on changes in the clarity of rye and plum distillates, and their content of volatile compounds. Distillates with initial ABVs of 93.26% v/v (rye distillate) and 82.03% v/v (plum distillate) were diluted with deionized water to 40, 50, and 70% v/v. The samples were stored in darkness at different temperatures (−18 °C, 0 °C, 8 °C, 20 °C) for 8 weeks. The results showed that reducing the alcohol content and storage temperature caused turbidity to increase. The samples prepared from rye distillate were characterized by significantly lower turbidity than those produced from plum distillate. The highest increase in turbidity in comparison to the controls was observed in the samples with 40% v/v alcohol content stored at a temperature of −18 °C. Storage of the rye and plum distillates samples at different temperatures resulted in changes to the concentrations of volatile compounds, i.e., lower levels of acetaldehyde and higher alcohols, and increased content of esters. However, the alcohol content and storage temperature had no statistically significant effect on methanol concentration.

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