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Familial cold urticaria: a father and daughter with typical clinical and laboratory features.

BACKGROUND
Familial cold urticaria is a rare, autosomally dominant disease of interest to physicians treating urticarial-type diseases.


OBJECTIVE
To describe two patients, a father and daughter with the characteristics of this disease and review the features that differentiate it from other cold-induced syndromes.


METHODS
Both patients underwent a cold room challenge, a lesional skin biopsy, and an ice-cube test, P-K test and extensive laboratory studies pre- and post-cold-room challenge.


RESULTS
A careful history revealed winter outbreaks of erythematous, nonpruritic lesions occurring hours after cold air exposure since early childhood. Systemic symptoms included burning, chills, and arthralgias rather than the anaphylactic symptoms associated with acquired urticarias. Cold room challenge induced "non-urticarial" lesions after a delay of one-half to two hours. Lesional biopsy demonstrated polymorphonuclear infiltration with increased eosinophils. Ice-cube tests and P-K tests were negative, and laboratory studies were remarkable only for a rise in leukocytes and erythrocytic sedimentation rate after positive challenge. Abnormal serum proteins were not found.


CONCLUSION
Familial cold urticaria is an inherited disease with distinct characteristics that distinguish it from acquired cold urticarias and other cold-induced syndromes. Most importantly, lesions occur with a delay after exposure to cold air and are not urticarial. Anaphylactic symptoms do not occur and abnormal serum proteins are not found.