Anaphylaxis to Patent Blue V. II. A unique IgE-mediated reaction.

BACKGROUND: Patent Blue V (PBV) is injected in order to map sentinel nodes during cancer staging procedures. Anaphylactic reactions, allegedly IgE antibody mediated, have been reported. The aim of the study was to explore the immunological mechanism of anaphylaxis to PBV. METHODS: PBV allergen threshold basophil sensitivity, CD-sens, was performed on cells from nine patients diagnosed as having had adverse reactions to PBV. The mechanisms of the CD-sens were studied by immunological and immuno-chemical methods. RESULTS: Five of the nine patients had a positive CD-sens to PBV which was completely eliminated by washing the cells in phosphate buffered saline before allergen challenge. However, the positive CD-sens was completely reconstituted by incubating the cells in plasma or serum of that patient or the other PBV-anaphylactic patients for 15 min at room temperature. In some patients the factor mediating CD-sens was completely or partially destroyed by heating at +56 degrees C for 30 min or being exposed to the low pH used for elution from anti-Ig columns. A 1000-fold excess of monoclonal IgE blocked the reconstitution by approximately 50%. CONCLUSION: Anaphylactic reactions to PBV are mediated by IgE antibodies giving a classical CD-sens reaction. However, the allergenic configuration seems to constitute a structure completely dependent on PBV, as a hapten, linked to a, so far, unknown carrier that seems to be unique for patients having experienced a PBV-induced reaction. Further studies are needed to characterize the postulated carrier.

Anaphylaxis to Patent Blue V. I. Clinical aspects.

BACKGROUND: The dye Patent Blue V (PBV) is increasingly used for staging procedures in operable breast cancer, but is reported to cause adverse reactions. The aim of this study was to present the clinical features and the results of follow-up examinations in patients with such reactions. METHODS: We studied nine patients with hypersensitivity reactions to PBV between 1999 and 2006 who were identified through the Norwegian network for reporting and investigating allergic reactions during anesthesia. RESULTS: We observed incidences of 0.5% (7/1418) for all kinds of PBV reactions and 0.4% (5/1418) for anaphylaxis. Typical clinical features included: (i) cardiovascular and/or cutaneous symptoms, (ii) a delay in symptoms, compared to the time of dye injection, (iii) poor response to ephedrine and intravenous fluid, and (iv) need for adrenaline administration, sometimes prolonged, for circulatory stabilization. Cutaneous manifestations were noted in five of the seven patients with anaphylaxis and two additional patients without circulatory instability. During anaphylactic reactions, serum tryptase was increased in six patients and normal in one. Serum tryptase was normal in one patient with skin symptoms only. Skin prick tests to PBV were positive in all eight patients tested, including the two with skin manifestations only. CONCLUSION: The clinical features and the results of follow-up studies strongly suggest that these reactions are IgE mediated.

Factors maintaining the intraurethral pressure in women.

To determine the components of the intraurethral pressure at rest, five continent women were studied with simultaneous urethrocystometry, including urethral pressure profile measurements, before, during and after curarization, as well as after clamping of the arterial blood supply to the urethra. The results showed that the striated muscle component in the urethra and pelvic floor is responsible for one-third of the total intraurethral pressure. Another one-third is exerted by the urethral vascular bed. The remaining one-third is most probably attributable to the smooth musculature and connective tissues in the urethra and the periurethral tissues.