38 yo hispanic female with over one year of self reported red/itchy skin and hives only when exposed to cold weather. She can get these symptoms if the A/C is on high or in the car with A/C. These symptoms resolve with a hot bath. Antihistamines she reports cause her to feel very sleepy. Attached photos are from when her house was 68 degrees and she was symptomatic. I am concerned about cold urticaria and will have her return to the office for an ice cube test.
1) Based on the history and photos does cold urticaria appear to be the right diagnosis?
2) If the ice cube test is inconclusive, would you recommend any additional workup?
3) I will recommend layering and likely Loratadine in hopes this is the least sedating for her. Any additional treatment recommendations?
Agree that this patient may have cold urticaria given the small urticarial papules I see on the legs. Differential include chronic spontaneous urticaria versus other. I would try the ice cube challenge for diagnostic purposes and see. If it’s negative, I would send her to the Allergist if one is available in your area for further evaluation (prick testing, environmental allergens, etc). For symptomatic treatment, recommend non-sedating antihistamines such as Claritin or Allegra. Can do BID or TID. Also can consider montelukast as additional therapy if Claritin or Allegra fails. Can also add in zantac or pepcid to help with additional H2 blockade.