Vibha Sharma

Prevalence, outcome and pre-hospital management of anaphylaxis by first aiders and paramedical ambulance staff in Manchester, UK ☆

BACKGROUND Anaphylaxis is of increasing prevalence and concern in Western communities. Ambulance services are often called to deal with these emergencies. There are few published studies that examine the demand and management of allergic reactions by emergency services. The aim of this study was to investigate the frequency, severity and outcome of calls, as well as whether intramuscular adrenaline was required for successful management of allergic reactions by paramedics and first aiders. METHOD A retrospective study of all emergency calls for allergic reactions within Greater Manchester in a 12-month period by the North West Ambulance Service of the United Kingdom. RESULTS 816 (0.2%) of 401,152 incidents were due to allergic reactions (32/100,000/year). No patients died. In 457 (56%) patients this was the first allergic reaction. Intramuscular adrenaline was administered to 116 (14%) patients. Patients with respiratory/circulatory compromise were significantly more likely to be given intramuscular adrenaline by paramedics (14 (4.4-45)), but not by first aiders (1.9 (0.98-3.6)). Administration of adrenaline by first aiders was more likely in patients with a past history of allergic reactions (4.3 (2.3-8.1)) and where reactions occurred at non-residential addresses (4.6 (2.6-8.2)). CONCLUSIONS Emergency call-outs for allergic reactions made up <1% of total ambulance workload. Most cases were successfully managed without intramuscular adrenaline. Adrenaline appeared to be used appropriately by paramedics. The lack of correlation between clinical severity and adrenaline use by first aiders suggests that they may often not understand the correct clinical indications for this drug.

Severe vernal keratoconjunctivitis successfully treated with subcutaneous omalizumab

A 12-year-old boy with severe mixed limbal and palpebral vernal keratoconjunctivitis experienced persistent ocular symptoms despite treatment with topical corticosteroids or cyclosporine. Signs and symptoms resolved completely with monthly subcutaneous omalizumab, an immunomodulating biologic agent. To our knowledge, this is the first report of its use as a monotherapy agent to treat vernal keratoconjunctivitis.

The deep fascia of the thigh forms an impenetrable barrier to fluid injected subcutaneously by autoinjectors

Fluid injected from epinephrine auto-injectors into subcutaneous tissue is prevented from penetrating into the muscle by the deep fascia of the thigh. Intra-muscular injection will not occur during firing of an auto-injector if the needle tip is in the subcutaneous tissue.

Vitamin K status of preterm infants with a prolonged prothrombin time.

AIM To investigate the vitamin K status of preterm infants who have a prolonged prothrombin time (PT) in the first month of life. METHODS Measures of vitamin K status were assessed in 21 preterm infants who were found to have an abnormal PT, despite 0.2-0.5 mg vitamin K(1) prophylaxis at birth. RESULTS All infants had normal or supraphysiological vitamin K(1) concentrations and undetectable or, in one infant, insignificant PIVKA-II, indicating adequate vitamin K status. CONCLUSION In preterm infants born at <32 wk gestation who received > or = 0.2 mg vitamin K(1) after delivery, a prolonged PT in the first month of life is unlikely to be due to vitamin K deficiency.

Allergy testing in predicting outcome of open food challenge to peanut

FIG 1. Receiver operating characteristic curve illustrating sensitivity and specificity of peanut SPT, peanut specific IgE, and peanut components in relation to open oral peanut challenge. To the Editor: We read with interest the report by van Erp et al showing that in 81 Swedish children with suspected peanut allergy, 0.1 and 5.0 kUA/L Ara h2 cutoff values correctly predicted the outcome in 62% of children undergoing peanut double-blind placebocontrolled food challenge, and with the addition of basophil activation test Ara h 2 and 6 80% were correctly predicted. They proposed a flowchart for the diagnosis of peanut allergy. Clinicians managing peanut and other food allergies need diagnostic tools that are accurate, but also simple and readily available. Complex algorithms involving artificial specific IgE cutoffs and labor-intensive basophil activation test assays with restricted availability are not a practical option. We retrospectively surveyed the value of peanut skin prick, peanut IgE, and component allergy tests (Ara h 1, 2, 3, 8, 9) in predicting the outcome of 130 open peanut oral food challenges (OFCs) in children aged 1 to 18 years (median, 7 years) attending our specialist pediatric allergy center between 2012 and 2016. OFC was performed in children who had not reacted to peanuts since early childhood, where there was no history of direct ingestion of peanuts, or when the family members were too anxious to try the food. Written consent and approval was obtained from all patients. IgE concentrations were measured by automated Immuno-CAP250 processor (Thermo Fischer Scientific, Loughborough, United Kingdom). Sensitization was defined as peanut, or peanut component IgE level of 0.4 kUA/L or more, or a skin prick test (SPT) wheal size of 3 mm or more. Oral challenge with peanut butter (in children <6 years old) or shelled peanuts was performed using a standardized open-challenge protocol, increasing the amount of peanut every 15 minutes (25 mg, 100 mg, 200 mg, 1 g, 5 g, 20 g). A positive challenge was defined as objective signs of allergy (urticaria, angioedema, vomiting, wheeze). Eighty-eight (68%) passed their OFC. Twenty-four percent failed at 25 mg, 34% at stages 100 to 1000 mg, and 42% reacted to 5 g or more of peanuts. Only 1 patient suffered anaphylaxis (wheeze), requiring intramuscular epinephrine. Ara h 2 above our laboratory’s threshold of 0.4 kUA/L or more correctly identified 95% of children, with a positive predictive value of 94% and a negative predictive value of 97%. This was significantly higher than SPTs’ wheal size of 3 mm or more (positive, 75%; negative, 76%) and peanut allergen specific IgE level of 0.4 kUA/L or more (positive, 81%; negative, 84%) (Fig 1). A 2-year-old and a 5-year-old child had a negative Ara h 2 but failed the OFC, both reacting (vomiting and urticaria) after consuming 5 g or more of peanut. Although the diagnostic accuracy of OFC surrogates is likely to vary by region, and, for instance, in Mediterranean areas, Ara h 2 may have a lower predictive value, our study demonstrates that in the North West of England an Ara h2 peanut component above baseline (>_0.4 kUA/L) predicts the outcome of peanut OFC significantly better than either peanut SPT or peanut specific IgE. On the basis of our data and that of other studies, we suggest that peanut SPT and peanut specific IgE be replaced by Ara h 2 as the routine screening test for peanut allergy. Shelly Rajput, MB BS Vibha Sharma, MD Stephen M. Hughes, MD, PhD Carol I. Ewing, MD Peter D. Arkwright, MD, PhD From the University of Manchester and the Department of Paediatric Allergy & Immunology, Royal Manchester Children’s Hospital, Manchester, United Kingdom. E-mail: peter.arkwright@nhs.net. This study was funded by the University of Manchester. Disclosure of potential conflict of interest: V. Sharma serves on the board for Mead Johnson and Nutricia; receives grant support from the North West Paediatric Allergy network fund; and receives travel support from Alk-Abello, Allergy Therapeutics, MEDA, Mead Johnson, and Nutricia. C. I. Ewing serves as a consultant for NHS Trust Development Authority, England. P. D. Arkwright receives travel support from Allergy Therapeutics and Nutricia. The rest of the authors declare that they have no relevant conflicts of interest.

Vitamin K status of preterm infants with a prolonged prothrombin time: Short communications

Aim: To investigate the vitamin K status of preterm infants who have a prolonged prothrombin time (PT) in the first month of life. Methods: Measures of vitamin K status were assessed in 21 preterm infants who were found to have an abnormal PT, despite 0.2–0.5 mg vitamin K1 prophylaxis at birth. Results: All infants had normal or supraphysiological vitamin K1 concentrations and undetectable or, in one infant, insignificant PIVKA‐II, indicating adequate vitamin K status.