Pathology Quiz Case 1

Abstract

A 23-YEAR-OLD WHITE WOMAN PRESENTED with a 2-month history of a pyoderma gangrenosum–like ulcer in the right postauricular region. The cutaneous lesion had initially started as a pustule that was associated with local pain, subfebrile temperature, night sweats, and spontaneous perforation with a whitish discharge 2 weeks after the disease onset. Necrectomy was performed, and antibiotics (clindamycin, amoxicillin and clavulanate potassium [co-amoxiclav], and azithromycin) were administered intravenously in an outpatient clinic, without success. Two months after the first symptoms appeared, the patientwasadmitted toourclinic.Shehada4.5-cm-diameter, painful, necrotic area in the right postauricular and subauricular regions. The lesion was covered with granulation tissue and mucous discharge. In the left postauricular region, there was an indurated purple pustule, 2 cm in diameter, that was solid and painful to palpation. A smaller pustule was seen in the medial part of the left scapula. The patient also had painful episcleritis and uveitis of both eyes as well as granulation tissue in the septal and conchal mucousmembranes.Antibiotic therapy(piperacillinandgentamicinsulfate)wasadministeredintravenously,andasecond necrectomyoftherightpostauricularandsubauricularareas was performed on day 5 of admission. A huge ulcer penetrating deeply into the right parotid gland, almost to the facial nerve, was found on removal of the necrotic tissue (Figure 1). The tissue was sent for cytologic, microbiologic, andhistopathologic analysis.Cultureswerenegative for aerobic and anaerobic microorganisms and fungi. Cytologicexaminationshowedgranulomatous inflammation. Thehistopathologyreport revealed fibrinoidnecrosisof the vascular wall; macrophage, lymphocyte, and neutrophilic leukocyteinfiltration;andformationofgranuloma(Figure2 and Figure 3). What is your diagnosis?