The more allergens an atopic patient is exposed to, the easier and quicker anaphylactic shock and Kounis syndrome appear: Clinical and therapeutic paradoxes.

Kounis syndrome is a condition that combines allergic, hypersensitivity, anaphylactic or anaphylactoid reactions with acute coronary syndromes including vasospastic angina, acute myocardial infarction and stent thrombosis. This syndrome is a ubiquitous disease affecting patients of any age, involving numerous and continuously increasing causes, with broadening clinical manifestations and covering a wide spectrum of mast cell activation disorders. Drugs, environmental exposures and various conditions are the main offenders. Clinical and therapeutic paradoxes concerning Kounis syndrome therapy, pathophysiology, clinical course and causality have been encountered during its clinical course. Drugs that counteract allergy, such as H2-antihistamines, can induce allergy and Kounis syndrome. The more drugs an atopic patient is exposed to, the easier and quicker anaphylaxis and Kounis syndrome can occur. Every anesthetized patient is under the risk of multiple drugs and substances that can induce anaphylactic reaction and Kounis syndrome. The heart and the coronary arteries seem to be the primary target in severe anaphylaxis manifesting as Kounis syndrome. Commercially available adrenaline saves lives in anaphylaxis but it contains as preservative sodium metabisulfite and should be avoided in the sulfite allergic patients. Thus, careful patient past history and consideration for drug side effects and allergy should be taken into account before use. The decision to prescribe a drug where there is a history of previous adverse reactions requires careful assessment of the risks and potential benefits.

Prasugrel versus high dose clopidogrel to overcome early high on clopidogrel platelet reactivity in patients with ST elevation myocardial infarction.

OBJECTIVE: There is a paucity of data regarding the early effectiveness of the proposed 600 mg clopidogrel loading dose (LD) on platelet reactivity (PR) in ST elevation myocardial infarction (STEMI) patients. If high on-treatment platelet reactivity (HTPR) is present, prasugrel reloading and subsequent maintenance dose (MD), might offer faster and stronger platelet inhibition than high clopidogrel MD. METHODS: In 93 STEMI patients treated by primary percutaneous coronary intervention we assessed PR using the VerifyNow P2Y12 platelet function test, 2 h following 600 mg LD of clopidogrel. All the 60 (64.5 %) patients exhibiting HTPR (defined as PR ≥ 235 P2Y12 reaction units), were randomized to 1 of 2 therapeutic strategies: reloading with prasugrel 60 mg/10 mg MD or high (150 mg) clopidogrel MD. RESULTS: The primary endpoint of PR at 24 h post randomization was lower in the prasugrel compared to the clopidogrel group (51.3, 25.7-77.0 versus 242.4, 215.8-268.9 P2Y12 reaction units, least square estimates, 95 % confidence intervals, p < 0.001). PR at 2 h and 5 days post randomization was lower in the prasugrel compared to the clopidogrel group (117.2, 70.9-163.4 and 101.6, 70.1-133.2 least square mean difference, 95 % confidence intervals, p < 0.001 for both). At all the time points of PR assessment, HTPR rates were lower in prasugrel than in clopidogrel group. CONCLUSIONS: HTPR is commonly observed early post 600 mg clopidogrel LD in STEMI patients. In this case, prasugrel 60 mg LD/10 mg MD provides faster and stronger platelet inhibition than a high clopidogrel MD regimen.