Allergic myocardial infarction (Kounis Syndrome)- non-ST elevation MI following Omnipaque contrast.

Kounis Syndrome is an acute coronary syndrome in the setting of mast cell activation. Mast cell activation can be due to anaphylaxis, anaphylactoid reaction, allergies, or hypersensitivities. Three reported variants of Kounis Syndrome include: vasospastic allergic angina, allergic myocardial infarction, and stent thrombosis. Herein, we described a case of Type 2 Kounis Syndrome following iodinated contrast infusion for a fistulogram, which manifested as a rare non-ST elevation myocardial infarction (NSTEMI).

Radiochemical Feasibility of Mixing of 99mTc-MAA and 90Y-Microspheres with Omnipaque Contrast.

Yttrium-90 (90Y) microspheres are widely used for the treatment of liver-dominant malignant tumors. They are infused via catheter into the hepatic artery branches supplying the tumor under fluoroscopic guidance based on pre-therapy angiography and Technetium-99m macroaggregated albumin (99mTc-MAA) planning. However, at present, these microspheres are suspended in radiolucent media such as dextrose 5% (D5) solution. In order to monitor the real-time implantation of the microspheres into the tumor, the 90Y microspheres could be suspended in omnipaque contrast for allowing visualization of the correct distribution of the microspheres into the tumor. The radiochemical purity of mixing 90Y-microspheres in various concentrations of omnipaque was investigated. The radiochemical purity and feasibility of mixing 99mTc-MAA with various concentrations of a standard contrast agent were also investigated. Results showed the radiochemical feasibility of mixing 90Y-microspheres with omnipaque is radiochemically acceptable for allowing real-time visualization of radioembolization under fluoroscopy.

Development of a capillary electrophoretic method for determination of plasma clearance of iohexol in dogs and cats.

Renal function can be monitored by estimation of the glomerular filtration rate (GFR), for example, through measurement of the plasma clearance of a marker that is freely filtrated through the kidney without reabsorption. It has been proposed that iohexol is the most accurate marker for GFR determination in cats and dogs. However, there is a need for a validated capillary electrophoretic method that covers the concentration range for a full curve clearance estimate of iohexol. In the final method, the plasma samples were protein precipitated and the supernatant was analyzed in a background electrolyte containing borate buffer (0.06 m, pH 10.0). The method developed was proved to be linear (concentration range 18- 2900 mg/L) and had a good precision (e.g. 2.3-2.9% at 88 mg/L) and accuracy (e.g. 101-105% at 88 mg/L). Finally, the method was compared with a previously published and validated HPLC-UV method by parallel analysis of clinical plasma samples from dogs and cats administered Omnipaque®. This comparison showed excellent agreement between the two methods and no proportional or systematic error was observed. The proposed method is simple and has a low cost per sample, which makes it applicable for routine analysis.

Successful Desensitization to the Radiocontrast Material Iohexol (Omnipaque™).

Adverse reactions to radiocontrast media (RCM) are rare and occur predominantly in association with intravenous administration but may also occur with intra-arterial and nonvascular injections (e.g., retrograde pyelography, intra-articular injections) of RCM. This article reports the case of a 52-year-old lady who was known to have amyloidosis secondary to rheumatoid arthritis and was on regular renal replacement therapy. She was under follow-up for regular angioplasties to manage the central vein stenosis that was affecting her right brachiocephalic arteriovenous fistula (AVF) and was referred to our Immunology service when she developed an allergic reaction after her AVF angioplasty (central venoplasty). Despite being dialysed immediately post-angioplasty, she complained of skin rash and itching with hoarseness of voice that developed almost six to eight hours post-angioplasty. We decided to arrange the iodinated non-ionic iso-osmolar contrast agent iodixanol (Visipaque™) for her instead, as it is known to be better tolerated in patients with reactions to Omnipaque™ due to its lower osmolarity as compared to Omnipaque™. However, since it was the first time to request this contrast in our hospital, it was not possible due to logistical reasons. It was necessary that our patient continued to undergo angioplasty every three months, however, she was developing more severe and earlier symptoms with each subsequent exposure to the radiocontrast medium. After her latest reaction of generalized itching and angioedema with shortness of breath during the procedure despite premedication, it was decided for her to undergo desensitization to Omnipaque™. In the absence of a published protocol for this, we used a protocol used for desensitization to Visipaque™. She showed an excellent response and completed her remaining angioplasties until Visipaque™ became available. Hence, desensitization to Omnipaque™ using the published protocol to Visipaque™ is likely to help patients allergic to Omnipaque™ or where Visipaque™ is not available or non-affordable in low/middle-income countries.

Hydrogen bound water profiles in the skin influenced by optical clearing molecular agents-Quantitative analysis using confocal Raman microscopy.

Confocal Raman microscopy has been used to measure depth-dependent profiles of porcine skin ex vivo in the high wavenumber region after application of molecular optical clearing agents (OCAs). Glycerol (70%) and iohexol (100% Omnipaque [300]) water solutions were used as OCAs and topically applied to porcine ear skin for 30 and 60 minutes. Using Gaussian function-based deconvolution, the changes of hydrogen bound water molecule types have been microscopically analyzed down to the depth of 200 µm. Results show that both OCAs induced skin dehydration (reduction of total water), which is 51.3% for glycerol (60 minutes), 33.1% for glycerol (30 minutes), 8.3% for Omnipaque (60 minutes) and 4.4% for Omnipaque (30 minutes), on average for the 40 to 200 µm depths. Among the water types in the skin, the following reduction was observed in concentration of weakly bound (51.1%, 33.2%, 7.5% and 4.6%), strongly bound (50.4%, 33.0%, 7.9% and 3.4%), tightly bound (63.6%, 42.3%, 26.1% and 12.9%) and unbound (55.4%, 28.7%, 10.1% and 5.9%) water types on average for the 40 to 200 µm depths, post application of glycerol (60 minutes), glycerol (30 minutes), Omnipaque (60 minutes) and Omnipaque (30 minutes), respectively. As most concentrated in the skin, weakly and strongly bound water types are preferentially involved in the OCA-induced water flux in the skin, and thus, are responsible for optical clearing efficiency.

Comparative study of renal protective effects of allopurinol and N-acetyl-cysteine on contrast induced nephropathy in patients undergoing cardiac catheterization.

UNLABELLED: Objectives : To evaluate the difference in the renal protective effects of allopurinol and n-acetyl cysteine along with saline hydration in patients of contrast induced nephropathy (CIN) post cardiac interventions. BACKGROUND: CIN remains a common complication of cardiac procedures. Radio contrast agents can cause a reduction in renal function that may be related to oxidative stress underlining various patho- physiologies. Conflicting evidence suggests that administration of allopurinol, a xanthine oxidase inhibitor can prevent CIN. MATERIALS AND METHODS: This is a study of 500 patients undergoing angiography and coronary revascularisation in patients showing significant coronary block. The angiography positive patients (275) were prospectively randomised to different treatment protocol to study for their reno-protective effect. The patients received either of the three drugs saline hydration (SH, 1ml/kg/hr), n-acetylcysteine (SH+NAC, 600 mg bd) or Allopurinol (SH+ALLP, 300 mg/day) 12 hours before and after administration of radio contrast agent. Levels of serum creatinine and blood urea of the 275 patients recorded at 24 hour interval were noted post angioplasty over a course of 5 days in patients receiving either omnipaque (125) or visipaque (150) contrast media. All the 500 patients were also assessed for development of any kind of adverse drug effects/reactions with the two contrast media. RESULTS: CIN occurred in 56 of 500 the patients (10.6%) who underwent angiography and 49 of 275 patients (17.8%) who underwent angioplasty. In the omnipaque group CIN occurred in 16/40, 8/40, nil/45 in patients receiving SH, NAC plus SH and SH plus ALLP respectively. In the visipaque group CIN occurred in 15/50, 10/50, nil/50 in the three treatments groups respectively. Allopurinol maintained a consistent fall in the serum creatinine & blood urea levels from the baseline values from the end of the 1(st) day (p < .01 & .001) in both the category. Visipaque proved to be better dye than omnipaque with less adverse drug effects/ reactions. CONCLUSION: Prophylactic oral administration of allopurinol (300 mg/day) along with hydration is better than n-acetylcysteine and saline hydration alone for protection against CIN in patients undergoing coronary procedures.