Immunotherapy Safety for the Primary Care ... - U.S. Coast Guard

mastocytosis on bone marrow biopsy. Both may have elevated plasma
histamine, urinary histamine, and serum tryptase levels. Suspicion of the
diagnosis should be raised with the recognition of the classic reddish
brown macular-papular skin lesions with a positive Darier’s sign.
(urticaria pigmentosa)
• Cold urticaria. These patients can present with generalized urticaria,
angioedema, laryngeal edema, and vascular collapse, resulting from a
massive outpouring of histamine. The history is usually suggestive,
especially if they have a positive past history of urticaria with cold
stimulus. These patients are usually particularly at risk with aquatic
activities, and the precipitating stimulus is frequently swimming in cold
water.
• Serum sickness. May present with urticaria, but is generally not an abrupt or
progressive event. Associated with fever, lymphadenopathy, and arthritis
• Carcinoid syndrome. Carcinoid symptoms may sometimes be mistaken for
anaphylaxis, given the presence of flushing, tachycardia, hypotension,
gastrointestinal symptoms, and bronchospasm. However, urticaria and
angioedema are absent, and upper respiratory tract obstruction does not
occur. Occasionally, carcinoid syndrome may have elevated 24-hour urine
histamine; however they also have increased urinary levels of 5-HIAA.
Nonimmunologic Risk Factors for Severe or Fatal Anaphylaxis
• Beta-adrenergic blockade.
• The presence of beta-adrenergic blocking drugs may increase the likelihood of
anaphylaxis.
• It definitely increases its severity and interferes with the use of epinephrine to
treat anaphylaxis.
• It acts to block the expected beta-i and beta-2 anti-anaphylactic actions of
epinephrine, thus facilitating unopposed aipha-adrenergic effects, which
in the presence of excess epinephrine, may constrict coronary arteries and
dangerously exaggerate the systemic pressor effects of epinephrine.
In addition, reflex vagotonic effects that can lead to augmented mediator
release, bronchoconstriction, and bradycardia.
• Even small amounts of the drug, such as that absorbed from Timoptic eye drops,
can cause problems.
• Asthma. Asthmatic patients appear to be twice as likely to die if anaphylaxis occurs.
• Cardiac disease. Anaphylaxis is more likely to be severe or fatal in patients with
congestive heart failure or arteriosclerotic coronary artery disease.
• Parenteral administration: Oral administration appears to be the safest, while the
parenteral route is the most hazardous.
• Delayed anaphylaxis.
A more prolonged period between antigen exposure and onset of symptoms
(latent period) has been thought to be associated with a more benign outcome; however, a
recent prospective study of anaphylaxis in 25 consecutive patients by Sullivan (Dallas,
Texas) suggests that patients with delayed onsets may be at greater risk of a fatal