Dry purpura and wet purpura.

Q: Dry purpura is more pathognomonic than wet purpura.

A) True

B) False

Answer: B

Purpura is defined as coalesced petechiae, which are small, flat, red, and discrete areas of bleeding.

Dry purpura usually means purpura in the skin, and wet purpura means hemorrhagic blisters in mucous membranes. The most common cause is thrombocytopenia. Wet purpura is the most predictive of severe bleeding.

Purpura due to vasculitis is usually palpable and may be pruritic, and the distribution does not follow dependent areas.

#physical-exam

#dermatology

#hematology

References:

1. Mishra K, Jandial A, Malhotra P, Varma N. Wet purpura: a sinister sign in thrombocytopenia. BMJ Case Rep. 2017 Sep 1;2017:bcr2017222008. doi: 10.1136/bcr-2017-222008. PMID: 28864561; PMCID: PMC5589040.

2. Crosby WH. Editorial: Wet purpura, dry purpura. JAMA. 1975 May 19;232(7):744-5. doi: 10.1001/jama.232.7.744. PMID: 1173178.