I am not certain I understand your question completely as I am not sure what you meant by “end point of Csa protocols”. I am interpreting this as you feel more comfortable with an immunomodulator other than omalizumab.
Aquagenic urticaria is very rare and I do not have any personal experience in management. As with any physical urticaria, modification of activities to limit exposure to the inciting agent is helpful but not always feasible. Higher doses of H1 and possibly H2 inhibitors may be helpful if this has not been tried. I would favor this over cyclosporine or other calcineurin inhibitors due to less side effects.
I do not know the significance of anti-IgE antibody in a physical urticaria but certainly in spontaneous or idiopathic urticaria this has been described. It is reasonable that anti-IgE may increase the susceptibility to water exposure in triggering the urticaria.
In summary, I would suggest treating your patient as you would for spontaneous or idiopathic urticaria, increased H1 inhibitor up to four times the recommended dose of a 2nd or 3rd generation antihistamine with or without H2 inhibitor and/or leukotriene antagonist. I would caution her about sudden, whole body water exposure and provide epinephrine autoinjector due to risk of hypotension if there was sudden water exposure. I would not recommend omalizumab or calcineurin inhibitors or other immunomodulators at this time due to lack of indication for omalizumab and potential side-effects of calcineurin inhibitors. I would not modify the treatment program based upon the anti-IgE antibody as the role of such antibodies is unproved in idiopathic/spontaneous urticaria and physical urticaria. Application of petrolatum prior to swimming is a consideration (McGee). A recent review of aquagenic urticaria is provided by Casale et al.
I have provided a quote from the practice parameters concerning autoantibodies in urticaria (Pactice Parameters Chronic Urticaria 2014).
“Although commercial assays are now available, the utility of testing for autoantibodies to the high-affinity IgE receptor or autoantibodies to IgE has not been established. Whether detection of autoantibodies identifies a clinically unique population or will lead to a change in management is also currently unclear. Although some studies have suggested that a positive autoantibody test result might indicate a marker of increased disease severity, data are limited and might reflect the fact that these populations do not differ clinically and that these autoantibodies might represent an epiphenomenon. For these reasons, autoantibody-associated CU has been included under the diagnosis of CIU.”
McGee, Jean S., et al. "An adolescent boy with urticaria to water: review of current treatments for aquagenic urticaria." Pediatric Dermatology 31.1 (2014): 116-117.
Casale, Thomas B., Jonathan A. Olsen, and Harold C. DelasAlas. "Aquagenic Urticaria." The Journal of Allergy and Clinical Immunology: In Practice 1.3 (2013): 295-296.
I hope this information is of help to you and your patient.
All my best.
Dennis K. Ledford, MD, FAAAAI