RT Book, Section A1 Dooley-Hash, Suzanne A1 Herrman, Nicholas W.C. A2 Knoop, Kevin J. A2 Stack, Lawrence B. A2 Storrow, Alan B. A2 Thurman, R. Jason SR Print(0) ID 1181041417 T1 Chancroid T2 The Atlas of Emergency Medicine, 5e YR 2021 FD 2021 PB McGraw-Hill PP New York, NY SN 9781260134940 LK accessemergencymedicine.mhmedical.com/content.aspx?aid=1181041417 RD 2024/04/19 AB Chancroid is caused by Haemophilus ducreyi. Following a 4- to 10-day incubation period, patients develop erythematous papules that evolve into pustules. The pustules then erode forming painful ulcers. Differential diagnosis should include other causes of genital ulcerations including genital herpes and syphilis. Painful, suppurative inguinal lymphadenopathy develops in almost 50% of cases. Large infected lymph nodes may spontaneously rupture. Systemic symptoms are uncommon.