J ALLERGY CLIN IMMUNOL

VOLUME 133, NUMBER 2

Abstracts AB27

SATURDAY

97 Omalizumab For a Case Of Monoclonal Mast Cell Activation

Syndrome With Recurrent AnaphylaxisDr. Amanda Jagdis1, Dr. Peter Vadas, MD, PhD2; 1University of Toronto,

Faculty of Medicine, Toronto, ON, Canada, 2St. Michael’s Hospital,

Toronto, ON, Canada.

RATIONALE: Monoclonal mast cell activation syndrome (MMCAS) is a

clonal mast cell disorder presenting with recurrent anaphylaxis due to mast

cell mediator release. Antihistamines, antileukotrienes and mast cell

stabilizers are used to prevent anaphylaxis, but control can be difficult to

achieve. Omalizumab is a humanized murine monoclonal antibody

that binds free IgE in serum, preventing IgE binding to the surface of

mast cells/basophils. There are only a few case reports on use of

omalizumab in MMCAS. Here, we present a case of MMCAS with

recurrent unprovoked anaphylaxis responding to treatment with

omalizumab.

METHODS: n/a

RESULTS: A 31 year old female presented with elevated baseline serum

tryptase and 6 multisystem anaphylactic reactions over 8 months. Bone

marrow biopsy showed increased mast cells and a single cluster of mast

cells with positive mutational analysis for c-kit Asp816Val, confirming

MMCAS. Initial medications included: cetirizine 20mg daily, ranitidine

150mg BID, montelukast 10mg daily, sodium cromoglycate 200mg TID.

In total, 20 unprovoked reactions occurred over 16 months, requiring

emergency room (ER) treatment and >17 doses of epinephrine.

Ketotifen 4mg BID, tapering Prednisone courses and Plaquenil 200mg

daily were added without improvement. Plaquenil was discontinued and

omalizumab initiated at 300mg q4 weeks 4 months ago. Omalizumab

has been well tolerated and thus far the patient has had only one reaction,

not requiring epinephrine.

CONCLUSIONS:MMCAScan be associatedwith recurrent, unprovoked

anaphylaxis despite maximal treatment. This case suggests that omalizu-

mab may be an effective adjunct to therapy in patients with MMCAS and

life-threatening reactions refractory to maximal medical therapy.

98 Chlorhexidine Impregnated Central Venous Lines: A PotentiallyAvoidable Cause Of Severe Perioperative Anaphylaxis

Dr. Aisha Ahmed, MD, Dr. Katherine E. Gundling, MD; UCSF, San

Francisco, CA.

RATIONALE: Chlorhexidine use is becoming increasingly common in

the health care setting, particularly in the perioperative setting. Its

anti-septic properties confer ubiquitous use, from pre-operative shower

solutions to antiseptic skin preparation and urinary catheters and gels. An

often overlooked source of exposure is in central venous catheters (CVCs),

which, in the case of allergic individuals, can cause life-threatening

anaphylaxis.

METHODS: First, we examine a near death reaction to chlorhexidine from a

CVC placed in the OR after careful planning following a previous severe

anaphylaxis in the same setting. Second, we evaluate reported cases of

perioperative anaphylaxis todeterminewhether chlorhexidineallergic patients

can be identified preoperatively. Third, we analyze the range of hospital and

household products that might induce chlorhexidine sensitization.

RESULTS: On two sequential attempts at surgery for malignant

Schwannoma the patient experienced severe perioperative anaphylaxis

requiring prolonged resuscitation due to the unrecognized presence of

chlorhexidine in the CVC. Each insertion of a CVC resulted in a large,

direct systemic exposure to the allergen. A review of chlorhexidine related

perioperative anaphylaxis literature reveals that prior cutaneous reactions

to chlorhexidine products are not uncommon.

CONCLUSIONS: Perioperative anaphylaxis to chlorhexidine can be

severe due to its unexpected presence in CVCs, which also confer an

immediate, systemic antigenic exposure. We propose that all patients be

asked about previous cutaneous reactions prior to surgery, and that positive

histories be clarified with chlorhexidine specific IgE, prick skin testing or

complete avoidance of chlorhexidine perioperatively. We describe several

important hospital and household products thatmight induce chlorhexidine

sensitization.

99 Food Dependent Exercise Induced Anaphylaxis Treatment WithSpecific Oral Tolerance Induction Using IFN-Gamma

Dr. Jae Ho Lee, MD, PhD1, Dr. Sun Young You, MD2, Dr. Hye Young

Han, MD3; 1Department of Pediatrics, Chungnam National University,

Taejeon, South Korea, 2Department of Pediatrics, Taejeon, South Korea,3Department of Pediatrics, School of Medicine, Chungnam National

University, Taejeon, South Korea.

RATIONALE: Food dependent exercise induced anaphylaxis (FDEIA)

was induced by exercise within three or four hours after ingestion of

specific allergenic foods. There is no specific treatment method. The

avoidance of allergenic food with exercise is the only way to treat the

FEDIA.

METHODS: The patient of FDEIAwas women. The blood test, skin prick

test and oral food challenge test were performed. FDEIAwas confirmed by

food allergy provocation test at the low dose of wheat with exercise. The

anaphylactic reactions were not occurred only by wheat intake or only by

exercise. The severity scores of 0 became to more than 2000 after oral food

challengewith exercise by running for ten minutes. The patient was treated

with the method of specific oral tolerance induction (SOTI) using

IFN-gamma. Exercise was accompanied every treatment just after intake

of wheat during treatment.

RESULTS: The treatment method of SOTI using IFN-gamma was

effective for FDEIA. The exercise was accompanied after intake of

wheat during the treatment. The tolerance to wheat was induced

successfully. after treatment. The patient could take wheat freely without

problems.

CONCLUSIONS: A patient of FDEIA was treated successfully with

SOTI using IFN-gamma. This treatment method should be effective for the

causative treatment of FDEIA.

100 Food Associated Exercise Induced Anaphylaxis AssociatedWith Late Phase Skin Test Reactivity To Shrimp

Dr. Marisol Nardi1, Dr. Robert Yao-Wen Lin, FAAAAI2; 1New York

Downtown Hospital, New York, 2New York Downtown Hospital, New

York, NY; Weill Cornell Medical College, New York, NY.

RATIONALE: Specific IgE typically identifies the offending food in food

dependent exercise induced anaphylaxis (FDEIA). We present a woman

whose history was consistent with FDEIAwhere the culprit food allergen

was identified only by a late phase skin test reaction.

METHODS: Case report of an FDEIA patient studied with exercise

testing, mediator release, skin testing and ImmuncapTM.

RESULTS: A 22 year-old woman reported urticaria and syncope while

running after eating shrimp dumplings. There was associated pruritus,

chest tightness, nausea and vomiting. She had an history of allergic rhinitis

and eczema. Prick skin tests(ST) and ImmunocapTM were positive for crab

but negative for shrimp. Serum tryptase, plasma histamine, thyroid

antibody levels and anti-Fc Epsilon receptor antibody levels were normal.

Intradermal ST with crab and shrimp(at 1/10 prick test concentrations)

were performed 24 hours prior to an exercise challenge test(Modified

Bruce protocol) and showed only significant wheal and flare reactions

for crab. Elevated plasma histamine levels were observed immediately

post-exercise(after achieving target heart rate) without allergic symptoms

or signs. Four hours after exercise testing, the prior day’s intradermal

shrimp and crab test sites enlarged to 13mm and 7mm respectively,

were associated with significant pruritus(especially the shrimp site) and

persisted >1 day.

CONCLUSIONS: Intradermal skin test responses may be useful in

FDEIA. The phenomenon herein described has parallels to red meat

allergy in that intradermal not prick STwere diagnostic. We speculate that

in this case, exercise and intradermal ST were both required to produce

optimal cutaneous mast cell activation.