Palabras clave: Heparinas no fraccionadas. Heparinas de bajo peso molecular. Test intradérmicos. Prueba de provocación simple ciego. Valor predictivo negativo.

Reactions caused by photosensitivity, also called photodermatosis, are cutaneous reactions induced or exacerbated by exposure to electromagnetic radiation, including UV radiation, visible light, and infrared radiation. We present the case of a 41-year-old man with no personal history of allergy and who is referred to our Drug Allergy Unit for study. We performed a conventional patch test (non-irradiated) and photopatch (with the application of UVA) with reading at 48 and 96 hours and 24 hours after irradiation with an intensity of 5J/cm2. Drug-induced photosensitivity can manifest itself in two clinically indistinguishable forms: photoallergy and phototoxicity. Photoallergic reactions are due to an immunological response of type IV hypersensitivity (a cell-mediated mechanism). We present a case of photoallergy due to sensitization to naproxen, confirmed by photopatch tests.

Late decades of life are less populated in patients with HAE than in normal subjects suggesting reduced life expectancy. We investigated a role for AA-LTP through modification of incidence for cardiovascular and neoplastic diseases. METHODS: ITACA database was integrated adding data about patient's characteristics collected through a telephone-interview using a standardized questionnaire administered by a doctor. RESULTS: 289 patients, 158 female (55%), >18 y.o., (mean age of 49,4 6 16,4) participated in the study. 140 patients (48,4% total) did never received LTP, 129 (44,6%) were on AA-LTP, 19 (6,6%) on LTP with tranexamic acid, 7 (2,4%) on LTP with C1-INH. Hypertension was more common in patients on >10y/AA-LTP (OR 2.3; 95%CI 1,1-4,2) and hypercholesterolemia in those on >15y AA-LTP compared to patients without LTP (OR 2,4; 95%CI 1,0-5,4). Thirty seven patients (12,8%) had cardiovascular diseases, compared to 3,7% of the general Italian population without age correction. The prevalence of neoplasms (n517/289; 5,9%) was lower in the AA-LTP vs no AA-LTP (3/17 neoplasms; OR 0,02; 95%CI 0,05-0,72). CONCLUSIONS: HAE patients on AA-LTP appear to have increased risk for cardiovascular disease, but reduced number of neoplasms.

Background:Fentanyl is primarily an opioid agonist. It is frequently used in general anesthe-sia as a potent analgesic. It can be administered either orally, transdermally or systemically. Adverse ef-fects due to opium alkaloids are usually because of a non-specific histamine release. Only in a few cases, a true allergy mechanism could be involved. Immediate reactions to opioids are most frequent than de-layed reactions. In the past years, delayed reactions have increased in frequency because of the wide use of Transdermal Therapeutic System (TTS) with several opioids for its potent analgesic properties.Objective:The objective was to study delayed reaction to fentanyl TTS and cross-reactivity with other opioids.Methods:A 52-year-old man with a diagnosis of pancreatic cancer who began treatment for a bone me-tastases pain with fentanyl TTS, at a dose of 50 micrograms per hour (mcg/h) is the subject of the study. After 10-15 days of treatment, he developed an itchy papulovesicular rash in the application site of the fentanyl TTS. Afterward, eczema and superficial desquamation just on the application site of the patch were observed. He changed several times the site of application, but always developing the same symp-toms in every single application. Later on, he tolerated other opioids such as oral morphine or tramadol. An allergy workout was performed. We performed Patch Tests (PT) with fentanyl at a concentration of 10% in aqua (aq) and with buprenorphine 10% aq., in order to investigate probable cross-reactivity among other topical opioids.Results:Readings were recorded at day 2 (D2) and day 4 (D4), with positive PT only with fentanyl at D2 (+++) and D4 (+++). We decided to perform a single-blind challenge test with buprenorphine 35 mcg/h in TTS, with a negative result. At this moment, fentanyl TTS was replaced by buprenorphine TTS, with good tolerance.Conclusion:We present the case of Allergic Contact Dermatitis (ACD) due to hypersensitivity to fenta-nyl with good tolerance to buprenorphine. Positive PT in this patient suggests a type IV hypersensitivity mechanism. Allergic reactions to opioids are frequently immediate, but delayed reactions could appear, especially when the drug is administered topically.

RATIONALE: Changes in emergency department (ED) concordance with guidelines for the management of insect sting-induced anaphylaxis are not known. Building on prior work (Clark et al, JACI2005;116:643-9), we describe temporal changes in ED concordance with guidelines for the management of insect sting-induced anaphylaxis. METHODS: We performed chart review for patients with insect stinginduced acute allergic reactions seen in one of ten EDs during two distinct time periods: 1999-2001 (prior study) and 2013-2015 (new study). Visits were identified similarly across studies-e.g., using ICD-9-CM codes 989.5, 995.0 and 995.3. Anaphylaxis was defined as an acute allergic reaction with involvement of 2+ organ systems or hypotension. We compared concordance between time periods with four guideline recommendations: 1) treatment with epinephrine, 2) referral to an allergist/ immunologist, 3) instructions to avoid the offending allergen, and 4) discharge prescription for epinephrine auto-injector (EAI). RESULTS: The analytic cohort included 959 patients (510 from 1999-2001 vs. 449 from 2013-2015). Overall, 283 patients had insect stinginduced anaphylaxis (158 [31%] vs. 125 [28%], respectively). Any treatment with epinephrine (pre-ED or in the ED) increased during over time (33% vs. 47%; P50.02). While documentation of instructions to avoid future stings did not change (23% vs. 26%; P50.65) and documentation for referral to an allergist/immunologist decreased (29% vs. 13%; P50.003), prescriptions for EAI at ED discharge increased from 34% to 60% (P<0.001). CONCLUSIONS: Over the ;15-year study interval, we observed increased ED concordance with epinephrine-related guidelines for the management of insect sting-induced anaphylaxis. Reasons for the decline in allergy/immunology referrals merits further study.