X-ray Contrast Media Research Articles

ANALYSIS OF DRUG-INDUCED ANAPHYLAXIS CASES USING THE JAPANESE ADVERSE DRUG EVENT REPORT DATABASE

The epidemiology of drug-induced anaphylaxis (AN) using the Japanese nationwide database has not been reported, even though drugs are a common trigger of AN. This study aimed to describe the epidemiological profile of drug-induced AN, including fatal cases, using the Japanese Adverse Drug Event Report database (JADER). We extracted data regarding drug-induced adverse events between April 2004 and February 2018 published in JADER by the Pharmaceuticals and Medical Devices Agency. We analyzed cases of anaphylaxis occurring between January 2005 and December 2017. The drug classification was based on the Japanese Standard Commodity Classification. There were 16916 cases of anaphylaxis reported during the study period. Among them, 418 fatalities were registered. The incidence of drug-induced AN and fatal cases was 1.03 cases/year per 100000 population and 0.03 cases/year, respectively. The most frequent causes of AN were diagnostic agents including X-ray contrast media (20.3%) and biological agents including human blood preparations (20.1%). In fatal cases, diagnostic agents (28.7%) and antibiotics (23.9%) were the most frequent causes. The frequency of drug-induced AN and fatalities in Japan remained unchanged over the 12-year period analyzed in this study. Diagnostic and biological agents were the most frequent causes of AN. Contrarily, fatalities were most frequently caused by diagnostic and antibiotic agents.

Transformation mechanisms of iopamidol by iron/sulfite systems: Involvement of multiple reactive species and efficiency in real water

Although the ability of iron/sulfite system for decontamination purposes has been investigated, the complex reactive species generated and the underlying transformation mechanisms remain elusive. Here, we have comprehensively examined the transformation of iopamidol (IPM), a representative of iodinated X-ray contrast media, by iron catalyzed sulfite oxidation process under different water chemistry conditions. Multiple reactive intermediates including Fe(IV), SO4•−, and SO5•− were identified by conducting a series of experiments. Eight transformation products were detected by mass spectrometry analysis, and correlation with the nature of involved reactive species has been made. Further, the transformation pathways including amide hydrolysis, deiodination, amino and hydroxyl groups oxidation were proposed. Interestingly, these transformation products could be removed through adsorption to iron precipitates formed via pH adjustment. Combining Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, we revealed an effective way to reduce the amount of transformation products in the treated solutions. Since the iron/sulfite process appears to be less sensitive to natural organic matter, it exhibited very good efficiency for IPM removal in real water samples, even with a high organic carbon loading. These findings may have strong implications in the development of novel oxidation process based on the sulfite/iron systems for wastewater treatment.

Improvement of the biodegradability of diatrizoate by electroreduction of its amido groups

The occurrence of iodine X-ray contrast media (ICM) in the environment is a global concern since they can be transformed into toxic compounds during water disinfection process. Among the different approaches that have been tested to degrade them, electroreduction offers the advantages to be selective, targeting in a cost-effective way the functional groups responsible for ICM biorecalcitrance and allowing the recovery of iodide ions. We have previously shown that total deiodination of diatrizoate, a highly biorecalcitrant ICM, did not lead to a significant enhancement of its biodegradability. In this work, the electroreduction of amido groups of diatrizoate was attempted to further improve its biodegradability. Electrolyses of diatrizoate and its deiodinated derivative, were investigated in neutral and acidic medium. A total deiodination of diatrizoate was rapidly achieved in both media along with a slower reduction of the amido groups, as shown by LC-MS/MS analysis of by-products. The biodegradability of the solutions was estimated by the evaluation of the BOD5/COD ratio. Results show that it was improved after the electroreduction performed in acidic medium. This result was confirmed by a biological treatment on activated sludge over a 21 days period, leading to mineralization yields of 46% and 68% for diatrizoate and 3,5-diacetamidobenzoic acid, respectively, after the electroreduction process.

Efficient Degradation of Iopromide by Using Sulfite Activated with Mackinawite.

Iopromide (IOP), an iodinated X-ray contrast medium (ICM), is identified as a precursor to iodide disinfection byproducts that have high genotoxicity and cytotoxicity to mammals. ICM remains persistent through typical wastewater treatment processes and even through some hydroxyl radical-based advanced oxidation processes. The development of new technologies to remove ICMs is needed. In this work, mackinawite (FeS)-activated sulfite autoxidation was employed for the degradation of IOP-containing water. The experiment was performed in a 500 mL self-made temperature-controlled reactor with online monitoring pH and dissolved oxygen in the laboratory. The effects of various parameters, such as initial pH values, sulfite dosages, FeS dosages, dissolved oxygen, and inorganic anions on the performance of the treatment process have been investigated. Eighty percent of IOP could be degraded in 15 min with 1 g L−1 FeS, 400 μmol L−1 sulfite at pH 8, and high efficiency on the removal of total organic carbon (TOC) was achieved, which is 71.8% via a reaction for 1 h. The generated hydroxyl and oxysulfur radicals, which contributed to the oxidation process, were identified through radical quenching experiments. The dissolved oxygen was essential for the degradation of IOP. The presence of Cl− could facilitate IOP degradation, while NO3− and CO32− could inhibit the degradation process. The reaction pathway involving H-abstraction and oxidative decarboxylation was proposed, based on product identification. The current system shows good applicability for the degradation of IOP and may help in developing a new approach for the treatment of ICM-containing water.

Baseline concentrations of pharmaceuticals in Kuwait's coastal marine environment

This study was carried out to provide baseline information on the concentrations of pharmaceuticals in Kuwait's coastal waters. Samples were collected over four sampling campaigns from various outfalls that occasionally discharged water into the marine environment and analyzed for a range of pharmaceuticals including analgesic/anti-inflammatories, antibiotics, anticoagulant, antidiabetic, antihelmintics, antihypertensives, antiplatelet agent, asthma medication, β-blocking agent, calcium channel blocker, diuretic, histamine H1 and H2 receptor antagonist, lipid regulators/cholesterol-lowering, prostatic hyperplasia, psychiatric drug, sedation and muscle relaxant, synthetic glucocorticoid, tranquilizer and x-ray contrast media. The levels varied between the detection limits of the method and a maximum of 28,183 ng/L for analgesics/anti-inflammatories. The highest pharmaceutical concentrations were in samples collected during the September campaign, possibly linked to the increased prescription of these medications to treat infectious diseases and flu prevalent in Kuwait during the winter months. The spatial variation is concentration is evident with KISR site being most polluted as hospital wastewater is discharged at the site. This study provides the first dataset on the concentrations of pharmaceuticals in the seawater in Kuwait and possibly the wider Arabian Gulf. Kuwait's coastal water pharmaceutical concentrations derived from this study exceed those reported from the Spanish coast, the Hong Kong harbour, the Bohai and the Yellow seas. More studies are needed to evaluate the environmental impact that these residues may have on non-target organisms.

Electro-reductive deiodination of iohexol catalyzed by vitamin B12 and biodegradability investigation

Owing to their high consumption for X-ray diagnose and to their rapid excretion from organism, iodinated X-ray contrast media (ICM) are often found in source waters. It is a serious public health concern due to their potential to generate highly toxic disinfection by-products. Reductive deiodination of ICM is considered as a promising approach to degrade them and allows the possible recovery of iodide ions. Electrocatalytic reduction of iohexol, an ionic ICM, was performed in the presence of vitamin B12 as catalyst. Vitamin B12 was chosen owing to its catalytic activity toward dehalogenation processes and to its positive effect on biodegradation of pollutants. The conditions for electrocatalysis were optimized to favor the electrocatalytic process over the direct reduction, leading to the enhancement of the reaction kinetic and the current efficiency. A total deiodination of iohexol was achieved after 1 h of electrolysis. A biological treatment with activated sludge underlined a low decrease of the dissolved organic carbon even after electroreduction. However, the concentration of iohexol decreased and a significant biotransformation of iohexol occurred, slightly improved by the presence of vitamin B12. The identification of the main by-products after the biotransformation of iohexol highlighted the oxidation of the primary and secondary alcohols of the alkyl chains.

Thiourea Dioxide Coupled with Trace Cu(II): An Effective Process for the Reductive Degradation of Diatrizoate.

Diatrizoate, a refractory ionic iodinated X-ray contrast media (ICM) compound, cannot be efficiently degraded in a complex wastewater matrix even by advanced oxidation processes. We report in this research that a homogeneous process, thiourea dioxide (TDO) coupled with trace Cu(II) (several micromoles, ubiquitous in some wastewater), is effective for reductive deiodination and degradation of diatrizoate at neutral pH values. Specifically, the molar ratio of iodide released to TDO consumed reached 2 under ideal experimental conditions. TDO eventually decomposed into urea and sulfite/sulfate. Based on the results of diatrizoate degradation, TDO decomposition, and Cu(I) generation and consumption during the TDO-Cu(II) reaction, we confirmed that Cu(I) is responsible for diatrizoate degradation. However, free Cu(I) alone did not work. It was proposed that Cu(I) complexes are actual reactive species toward diatrizoate. Inorganic anions and effluent organic matter negatively influence diatrizoate degradation, but by increasing the TDO dosage, as well as extending the reaction time, its degradation efficiency can still be guaranteed for real hospital wastewater. This reduction reaction could be potentially useful for in situ deiodination and degradation of diatrizoate in hospital wastewater before discharge into municipal sewage networks.

Analysis of Drug-Induced Gastrointestinal Obstruction and Perforation Using the Japanese Adverse Drug Event Report Database.

Drug-induced gastrointestinal obstruction (DIGO) and gastrointestinal perforation (DIGP) may be the result of gastrointestinal hypomotility and severe constipation, which may lead to potentially fatal complications of bowel ischemia, sepsis and perforation. We evaluated the onset profile of DIGs (DIGO and DIGP) associated with prescription drugs by analyzing data in the Japanese Adverse Drug Event Report (JADER) database. We selected 161 DIG-related drugs and categorized them into 19 classes based on the Anatomical Therapeutic Chemical (ATC) Classification System. Finally, we focused on 58 drugs and conducted subsequent analyses for the time-to-onset and outcomes. We extracted 79 preferred terms (PTs) with the strings “ileus,” “stenosis,” “obstruction,” “obstructive,” “impaction,” “perforation,” “perforated,” “hypomotility,” and “intussusception” from the Standardized Medical Dictionary for Regulatory Activities (MedDRA) Queries (SMQs) of SMQ20000104: gastrointestinal perforation, ulcer, hemorrhage, obstruction non-specific findings/procedures; SMQ20000105: gastrointestinal obstruction; and SMQ20000107: gastrointestinal perforation. Among the 667, 729 reports in the JADER database submitted between April 2004 and November 2020, we identified 11,351 occurrences of DIGs. The reporting odds ratios (RORs) (95% confidence interval) of “barium sulfate containing X-ray media,” “drugs for treatment of hyperkalemia and hyperphosphatemia,” and “oral bowel cleanser” were 142.0 (127.1–158.6), 25.8 (23.1–28.8), and 29.7 (24.8–35.6), respectively. The median number of days (interquartile range) until the onset of an adverse event caused by each drug category was as follows: barium sulfate containing X-ray contrast media [2.0 (1.0–3.0)], diazepines, oxazepines, thiazepines, and oxepines [8.0 (8.0–18.5)], drugs for treatment of hyperkalemia and hyperphosphatemia [29.0 (8.0–55.0)], non-selective monoamine reuptake inhibitors [19.0 (7.0–47.5)], and oral bowel cleanser [0.0 (0.0–0.0)]. Depending on the drug, the time to onset of side effects ranged from days to several months. Our results highlighted the need to perform detailed monitoring of each drug for possible association with DIGs, which might otherwise have fatal consequences.

Reliable kidney size determination by magnetic resonance imaging in pathophysiological settings.

Kidney diseases constitute a major health challenge, which requires noninvasive imaging to complement conventional approaches to diagnosis and monitoring. Several renal pathologies are associated with changes in kidney size, offering an opportunity for magnetic resonance imaging (MRI) biomarkers of disease. This work uses dynamic MRI and an automated bean-shaped model (ABSM) for longitudinal quantification of pathophysiologically relevant changes in kidney size. A geometry-based ABSM was developed for kidney size measurements in rats using parametric MRI (T2 , T2 * mapping). The ABSM approach was applied to longitudinal renal size quantification using occlusion of the (a) suprarenal aorta or (b) the renal vein, (c) increase in renal pelvis and intratubular pressure and (d) injection of an X-ray contrast medium into the thoracic aorta to induce pathophysiologically relevant changes in kidney size. The ABSM yielded renal size measurements with accuracy and precision equivalent to the manual segmentation, with >70-fold time savings. The automated method could detect a ~7% reduction (aortic occlusion) and a ~5%, a ~2% and a ~6% increase in kidney size (venous occlusion, pelvis and intratubular pressure increase and injection of X-ray contrast medium, respectively). These measurements were not affected by reduced image quality following administration of ferumoxytol. Dynamic MRI in conjunction with renal segmentation using an ABSM supports longitudinal quantification of changes in kidney size in pathophysiologically relevant experimental setups mimicking realistic clinical scenarios. This can potentially be instrumental for developing MRI-based diagnostic tools for various kidney disorders and for gaining new insight into mechanisms of renal pathophysiology.

Ionic and non-ionic intravenous X-ray contrast media: antibacterial agents?

X-ray contrast media have been reported to have inhibitory effects on bacterial growth. Despite its potentially beneficial effect on patients, these features of contrast media have received relatively little attention in the medical literature in the past decades. The aim of this review is to evaluate the literature concerning the bactericidal and bacteriostatic effects of X-ray contrast media, specifically if there is a known difference concerning these effects between ionic and non-ionic contrast media. Systematic literature review was performed for the years of publication between 1911 and 2019. Since the publication of Grossich in 1911, the effect of iodine on the treatment of superficial infections in surgical procedures has been established clinical knowledge. Bacteriostatic and bactericidal effects of ionic X-ray contrast media are well established. However, non-ionic contrast agents have been the subject of little research in this respect. In past decades, the hypothesis emerged in the literature that mainly the concentration of free iodine might be responsible for any bacteriostatic or bactericidal effect of ionic X-ray contrast media. Nowadays, however, only non-ionic contrast media are used. The question regarding the mechanism and magnitude of bacteriostatic or bactericidal effects of these, non-ionic contrast media, could not be answered conclusively from this review. Non-ionic contrast media could be used intentionally when a local antibacterial effect is intended (e.g. in percutaneous abscess drainage), as well as to reduce the overall dose of antibiotics administered to a patient. Thus, this question remains relevant and might constitute the area of future research.

Evaluating surrogate correlation models and iodinated haloacetic acid formation of iodinated contrast media after LPUV/Cl2, LPUV/NH2Cl, and LPUV/H2O2

Iodinated X-ray contrast media (ICM) are a class of pharmaceuticals that are ubiquitously found at trace levels (µg/L) in wastewater, surface water, groundwater, and drinking water. Due to their polar features, they are not effectively removed during conventional water treatment and provide an iodine source for the formation of iodinated-disinfection by-products (I-DBPs) during disinfection. This work examined the suitability of organic parameters (i.e. total organic carbon (TOC), ultraviolet absorbance (UVA254), total fluorescence (TF) and specific ultraviolet absorbance (SUVA)), as surrogate correlation models to estimate the removal of seven target ICMs. Three advanced oxidation processes (AOPs), LPUV/H2O2, LPUV/Cl2 and LPUV/NH2Cl, were applied to develop the surrogate correlation models. Pearson correlation coefficients were compared with linear correlation models to determine the ideal surrogate parameter for each model type. The formation of iodinated-haloacetic acids (I-HAAs) were also monitored for each AOP treatment. Results did not show any significant differences for ICM attenuation across the AOP treatments, illustrating UV photolysis is the main driving force to attenuate ICMs. Surrogate correlation models demonstrated a good correlation (R2 = 0.8211 and 0.7887) and strong Pearson correlation (R = 0.9602 and 0.8881) for UVA254 during LPUV/Cl2 and LPUV/H2O2 treatment. Additionally, two I-HAA, monoidoacetic acid (MIAA) and bromoiodoacetic acid (BIAA), were detected (up to 2.4 µg/L) after LPUV/Cl2 and LPUV/NH2Cl AOP treatment.

Reductive deiodination of 2,4,6-triiodophenol by Vallitalea sp. strain TIP-1 isolated from the marine sponge

An anaerobic microbial consortium capable of reductively dehalogenating 2,4,6-triiodophenol (2,4,6-TIP) was enriched from the marine sponge Hymeniacidon sinapium. The enrichment reductively deiodinated 100μM of 2,4,6-TIP to 4-iodophenol (4-IP) and 2-iodophenol (2-IP) in the presence of sterile sponge tissue as the sole carbon source and electron donor. PCR-denaturing gradient gel electrophoresis and 16S rRNA gene sequence analysis revealed that bacteria closely related with Vallitalea guaymasensis and Oceanirhabdus sediminicola, both of which are members of the order Clostridiales, were predominant in the enrichment. When glucose was added to the enrichment as alternative carbon source, one of these bacteria grew predominantly, which was subsequently isolated as a pure culture. The strain, designated as TIP-1, showed 99.7% 16S rRNA gene sequence similarity with V. guaymasensis. In the presence of glucose, strain TIP-1 reductively deiodinated 2,4,6-TIP to 2-IP and 4-IP at a molar ratio of 3:1, during which 2,4-diiodophenol (2,4-DIP) and 2,6-diiodophenol (2,6-DIP) were observed as deiodinated intermediates. Glucose was required for 2,4,6-TIP deiodination, but 2,4,6-TIP was not essential for growth of strain TIP-1. The strain also deiodinated 2,4-DIP to 2-IP and 4-IP at a molar ratio of 1:1, and 2,6-DIP to 2-IP, but further deiodination of the monoiodophenols was not observed. These results suggest that strain TIP-1 removed both ortho- and para-substituted iodines equally. Such deiodinating bacteria could be applied to the mineralization or dehalogenation of triiodobenzene derivatives, which are widely used as X-ray contrast media.

Persulfate enhanced visible light photocatalytic degradation of iohexol by surface-loaded perylene diimide/acidified biochar

Persulfate (PS) is extensively employed as an oxidant to develop the sulfate radical-based advanced oxidation processes for removing organic pollutants and various PS activation methods have been explored. Iohexol (IOH), as a typical iodinated X-ray contrast media, poses a threat to human health and ecological environment, which is difficult to be removed by conventional treatment methods. In our work, a photocatalytic coupling persulfate system was constructed for efficient IOH degradation. A novel binary photocatalyst of biochar loaded with perylene diimide (PDI/BC, PB) was successfully prepared via a one-pot water bath heating method, which achieved BC acidification and PDI self-assembly simultaneously. Different mass ratios of BC and PDI lead to variance in average particle size, electronegativity, bandgap width and electron/hole separation efficiency. The optimized efficiency of 10 mg/L IOH on PB-9 (PDI:BC = 1:9, w/w) reached 100% in 2 h with 1.5 mM sodium persulfate under visible light irradiation. Based on the results of trapping experiments and electron paramagnetic resonance, holes and hydroxyl radicals were the dominant active species and the free radical chain reaction and mutual conversion reaction of active species occurred. The amide hydrolysis, amine and C-OH oxidation, hydrogen extraction, deiodination and OH addition were observed during the degradation process. Density functional theory calculation was conducted to confirm the free radical attack sites. The findings of this work demonstrate that metal-free supramolecular loaded photocatalyst has the potential for application in the removal of organic pollutants for water remediation.

Quiescent-Interval Slice Selective Magnetic Resonance Angiography for Abdominal Aortic Aneurysm Treatment Planning

Purpose Diagnostic imaging of Abdominal aortic aneurysm (AAA) almost exclusively employs CT angiography (CTA) involving X-ray exposure and contrast medium that may harm some patients. Quiescent-Interval Slice Selective MR (QISS-MR) depicts vascular anatomy without radiation or contrast medium. The diagnostic quality of QISS-MRA and CTA were compared in regard to length and diameter measurements in AAA patients. Suitability of QISS-MRA for AAA treatment planning was evaluated. Materials and Methods The details of 30 patients with AAA who received both a QISS-MR and CTA for a known infrarenal AAA were obtained retrospectively that was approved by the local research ethics board. Two observers analyzed each dataset in terms of image quality and determined lumen diameter and length of 15 vessel segments. Results Highly accurate agreement between the diagnostic scores from the two observers was achieved. There was no significant difference between CTA and QISS-MRA for all 15 measured vessels. Although information on calcification was lacking and intraluminal thrombus was visualized in only 25 patients out of 30 patients, a founded decision to carry out OR or EVAR was possible with both imaging modalities. Conclusion QISS-MRA presents a radiation and contrast free method for preoperative diagnostic AAA imaging. While QISS-MRA does not deliver exact information regarding calcification and thrombus formation, it does accurately allow measurement of vessel diameter and length. Therefore, it is potentially useful for EVAR planning in selected patients with impaired renal function.

Iodinated trihalomethanes formation in iopamidol-contained water during ferrate/chlor(am)ination treatment

Iopamidol is a commonly used iodinated X-ray contrast media in medical field, and its residue in water can react with disinfectants to form highly toxic iodinated disinfection by-products (I-DBPs). This study investigated the degradation of iopamidol and formation of DBPs, especially iodinated trihalomethanes (I-THMs), during ferrate (Fe(VI)) pre-oxidation and subsequent chlor(am)ination under raw water background. It was found that iopamidol degradation efficiency in raw water by Fe(VI) at pH 9 could reach about 80%, which was much higher than that at pH 5 and pH 7 (both about 25%). With Fe(VI) dose increasing, iopamidol removal efficiency increased obviously. During the iopamidol degradation by Fe(VI), IO3− was the dominant product among all the iodine species. After pre-treated by Fe(VI), yields of THM4 and I-THMs can be reduced in subsequent chlor(am)ination. Besides, pH was a crucial factor for Fe(VI) pre-oxidition controlling DBPs. With the pH increasing from 5 to 9, the yield of THM4 kept increasing in subsequent chlorination but showed the highest amount at pH 6 in subsequent chloramination. The yield of I-THMs increased first and then decreased with the increase of pH in both subsequent chlorination and chloramination. I-THM concentrations in chlorinated samples were lower than chloraminated ones under acidic conditions but became higher under neutral and alkaline conditions. The total CTI of THMs during Fe(VI)-chloramination was higher than that during Fe(VI)-chlorination under neutral condition, but sharply decreased under alkaline conditions. In summary, Fe(VI)-chloramination subsequent treatment under alkaline conditions should be an effective method for iopamidol removal and DBP control.

Formation of toxic iodinated by-products during the oxidation process of iohexol by catalytic ozonation in water

The formation of iodinated by-products during the chemical oxidation process for organic compounds contaminated water has gained increasing attention. Iodinated by-products are more genotoxic, cytotoxic and mutagenic than those of chlorine and bromine analogs. It was reported that the oxidation process of iodinated X-ray contrast media (ICM) could generate iodinated by-products. This study investigated the generation of iodinated by-products during catalytic ozonation of iohexol (one of wide detected ICM). The formation of iodoform (IF) and monoiodoacetic acid (MIAA), and the degradation kinetics of iohexol were compared in different oxidation systems. The effect of various factors, including the iohexol concentration, ozone concentration, HA concentration and solution pH on iodinated by-products generation was evaluated. Additionally, the fate of iodine was investigated by the mass balance calculation. The generated concentrations of I-THMs species with one iodide atom were far higher than those of species with more iodine atoms in the catalytic system at the coexistence of Cl− and Br−. The generation of I-THMs in actual water was relatively low and the normalized value of I-THMs/DOC (μg/mg) had no significant difference. The formation mechanism of high molecular weight iodine-containing by-products included cleavage of the side chain, H-abstraction, substitution iodine for chlorine or bromine and amide oxidation.

Three-Step Diagnostic Assessment Following Adverse Reaction due to X-ray Contrast Media: An 11-Year Study in 47 Patients

Background: The diagnostic evaluation of adverse reactions occurring after iodinated contrast media is still debated. Immediate, delayed-type immune reactions and non-immune adverse events have to be differentiated. Our aim was to assess a safe three-step routine procedure in a single-center teaching hospital 2010-2021 with a prospective “real- life” outlook. Methods: Forty-seven patients after mild intermediate and severe adverse events were tested in three consecutive days. Skin prick tests with 2 to 5 undiluted media were followed at 24 hours by intradermal testing of 2 different concentrations each (10-2m and 10-3m). The results were red after both 20 and 70 minutes and at 24 hours. On day three one negative medium selected was 1/3 diluted and given intravenously under close observation. Results: The suspected 32 immediate, 11 delayed hypersensitive and 4 non-immune mediated reactors showed 22.3% skin prick test and 62.7% intradermal test positivity, 11 patients were all negative. The 70 minutes reading of intradermal tests modified the results obtained by 20 minutes. In 44.1% of the cases more and more pronounced positivity was found. The highest response rate was achieved by 10-3m solution of contrast media alone or in combination with 10-2m concentration. The only higher (10-2m) revealed 21.2%, while the only late(24 hours) manifesting tests only 8.1% positivity. Intravenous provocation confirmed in 32/38(84.2%) cases the selected alternative. Six cases were mildly positive. After testing the “real-life” versatility was 85% within the next year. Conclusion: The three-step workup shown in a single-center based study was proven useful and enabled repeated use of radio contrast media in problem patients.

Chloramination of iopamidol- and bromide-spiked waters containing natural organic matter

AbstractIopamidol (an iodinated X-ray contrast medium) and bromide are precursors in the formation of halogenated disinfection byproducts (DBPs). The interactions of these precursors are vital to elucidate the formation of halogenated DBPs during chloramination. This work investigated the formation of total organic halogen and select individual DBPs in two laboratory-chloraminated source waters containing iopamidol and bromide. Experiments were carried out in batch reactors containing Barberton source water (BSW) and Cleveland BSW (CSW), spiked with iopamidol (5 μM), bromide (15 μM), and 100 μM monochloramine. Total organic iodine concentrations were approximately equal regardless of source water since they are mostly unreacted iopamidol and iopamidol DBPs. Almost equal amounts of total organic chlorine (3–4 nM) were produced in the source waters, but higher quantities of total organic bromine were formed in BSW than CSW. Substantial quantities of regulated trihalomethanes (THMs) and haloacetic acids (HAAs) were formed in the source waters, along with appreciable concentrations of iodinated trihalomethanes (CHBrClI, CHCl2I, and CHBr2I). Low concentrations of iodo-HAAs were detected, especially at low pH. Overall, bromide concentrations appeared to suppress iodo-DBP formation during chloramination of iopamidol in the presence of natural organic matter. A good correlation (R2 = 0.801) between the yields of regulated DBPs and iodo-DBPs was observed.

Microbiological and Chemical Assessment of Wastewater Discharged by Infiltration Trenches in Fractured and Karstified Limestone (SCA.Re.S. Project 2019-2020).

This study investigated the environmental contamination of groundwater as a consequence of the discharge of treated wastewater into the soil. The investigation focused on a wastewater treatment plant located in an area fractured by karst in the Salento peninsula (Apulia, Italy). Water samples were collected at four sites (raw wastewater, treated wastewater, infiltration trench, and monitoring well), monthly from May to December 2019 (with the exception of August), and were tested for (1) panel of bacteria; (2) enteric viruses; and (3) chemical substances. A gradual reduction in the concentration of bacteria, viruses and contaminants of emerging concern was observed across the profile of soil fissured by karst. All monitored bacteria were absent from the monitoring well, except for Pseudomonas aeruginosa. Pepper mild mottle virus and adenovirus were detected at all sampling sites. Personal care products and X-ray contrast media showed the greatest decrease in concentration from infiltration trench to the monitoring well, while the highest residual concentrations in the monitoring well were found for anticonvulsants (78.5%), antimicrobials (41.3%), and antipsychotic drugs (38.6%). Our results show that parameters provided by current law may not always be sufficient to evaluate the sanitary risk relating to the discharge of treated wastewater to the soil.

Comparison Between Below Knee Contrast Enhanced Tomographic 3D Ultrasound and CT, MR or Catheter Angiography for Peripheral Artery Imaging

Clear imaging of below knee and foot arteries is essential to plan distal reconstructions. Contrast enhanced tomographic 3D ultrasound (CEtUS) is novel and entirely safe with no exposure to ionising radiation or nephrotoxic contrast. In the present study, inter- and intra-observer agreement of CEtUS was calculated, and compared with below knee angiography. In the same week as computed tomography, magnetic resonance or catheter angiography, CEtUS was performed using intravenous 1.2mL bolus injections of Sonovue with a maximum of 5mL administered per patient. CEtUS was reported by a vascular scientist blinded to the angiograms reported by a consultant radiologist. Images were compared using a modified Society of Vascular Surgery (SVS) runoff score. Of the 181 patients recruited with peripheral arterial disease, 20 were excluded from analysis as they withdrew consent, could not be cannulated, or their images were non-diagnostic. In the remaining 161 patients, there were 175 comparative patient images split into two groups: 81 had calf imaging and 94 had pedal imaging representing 405 and 198 imaged arteries, respectively. Weighted quadratic kappa/ICC values for intra- and inter-observer agreement were excellent (κ/ICC=0.83 to 0.95) and had narrow confidence intervals in both groups. When comparing angiography and CEtUS, weighted quadratic κ/ICC agreement was moderate with acceptable confidence intervals in both groups (Calf κ/ICC=0.54; Pedal κ/ICC=0.53). Agreement decreased from popliteal to pedal vessels as diameter decreased. Agreement between CEtUS and digital subtraction angiography was best, and computed tomography angiography the weakest. CEtUS is a novel imaging modality with strong observer agreement that achieves clear peripheral and foot images without ionising radiation exposure or nephrotoxic X-ray contrast media. CEtUS enhances visualisation of runoff vessels, which may play a role in planning of limb salvage or targeted assessment.