Images of Memorable Cases: Case 48 This 27-year-old man complained of fever and increasingly painful “knots” in his right groin. Confident that the patient had infectious lymphadenitis, his physician incised the affected nodes. No pus came forth. The operative site ulcerated, and in a span of two weeks became progressively red, hot, puffy, and tender. Antibiotic therapy had no effect. 48. Malignant lymphoma, histiocytic type Biopsy specimens of a right inguinal lymph node and adjacent ulcerated skin established the diagnosis. This case has a moral: When suspecting infectious lymphadenitis, remember lymphoma.