Delayed pressure urticaria due to blood pressure monitoring
The present case has been published in BMJ. A 68-year-old man presented with voiding lower urinary tract symptoms due to benign prostatic hyperplasia for which he underwent photovapourisation of the prostate using potassium titanyl phosphate laser. The procedure was completed in 104 min uneventfully.

Eight hours after the procedure, the patient had burning and itching on his left arm circumferentially in the area where the cuff for non-invasive blood pressure (NIBP) monitoring was applied and on his back.

The cuff was removed and in that region of his arm there was erythema along with multiple blisters (figure 1). A similar linear lesion was seen on the right side of his back along the 10th rib (figure 2). It was recognised it to be some form of urticaria, and immediately gave the patient an antihistamine (pheniramine). The patient had no history of any skin lesion, neither did he give a history of any allergies.

Both lesions appeared in areas where there was continuous pressure applied: in the arm by the blood pressure monitoring cuff and on the back while positioning on the operation theatre table against his rib.

A diagnosis of delayed pressure urticaria (DPU) was made, and the patient was given levocetrizine (5 mg) plus montelukast (10 mg) once daily along with oral prednisolone after which the lesions gradually subsided.

Learning points
• Delayed pressure urticaria is usually seen in patients with previous history of urticaria or angio-oedema, but the diagnosis may be missed if specific history regarding weals developing at sites of sustained pressure is not asked.

• The treatment with only antihistamines is not sufficient and requires additional therapy of oral steroids, non-steroidal anti-inflammatory drugs, colchicine, dapsone, sulfasalazine, intravenous immunoglobulins or omalizumab.

• If a patient with delayed pressure urticaria is posted for surgery then he should be carefully padded on the operating table, and non-invasive blood pressure monitoring should be minimum or invasive blood pressure monitoring can be used.

Read more here:
Dr. P●●●●●●●●●●●a G●●●●●●●●s b●●●t and 3 others like this