A 47-year-old woman presented with a painful, compressible, and mobile lump in the left axilla for three days without discharge or erythema. Prior to lump presentation, the patient had intermittent elbow and arm pain, lasting approximately 45 minutes. She denied fevers, chills, and night sweats. Her family history was significant for a father with liver cancer and maternal grandmother with bone cancer. She worked as a veterinarian and was a former smoker of five pack-years. On physical examination, there was a compressible, mobile, tender lump measuring 30 x 20 mm in the left axilla. Mammogram revealed normal right breast and left axillary lymphadenopathy (Figures , ). The ultrasound showed two adjacent enlarged axillary lymph nodes measuring 31 mm and 27 mm in diameter, respectively (Figure ).\nThe results from the mammogram and ultrasound supported the physical exam findings, prompting further CSD assessment with ultrasound-guided core biopsy. The biopsies showed necrotizing lymphadenitis that partially effaced the lymph node architecture. In the necrotic area, there were microabcesses with neutrophils and surrounding histiocytes, some of which were palisading (Figure ). Giant cells were scattered throughout. Staining for cluster of differentiation 20 and cluster of differentiation 3 showed some residual follicles and interfollicular T cells. Other stains including acid-fast bacilli, methenamine silver stain, toxoplasmosis, and periodic acid-Schiff were all negative. Cat scratch stain was positive. To confirm the diagnosis, serology for B. henselae was subsequently ordered with the results of abnormal B. henselae IgG titer of 1:1024, and abnormal B. henselae antibody IgM titer of 1:32.
A 25-year-old male patient with no significant past medical history presented with a three-day history of a tender mass in the right axilla along with fevers. The patient did not report any night sweats and weight loss. The mass showed no signs of drainage or infection. His physical examination revealed a 3 x 5 cm mobile, soft and non-nodular mass in the right axilla. An ultrasound of the right axilla showed a fluid-filled mass, which was concerning for an abscess. A needle aspiration was attempted without success; therefore, a referral to breast imaging clinic for a diagnostic ultrasound of the mass was initiated. Targeted ultrasound showed axillary lymphadenopathy at the site of the clinically palpable mass (Figure ). Ultrasound-guided biopsy was performed, and pathology revealed suppurative granulomatous lymphadenitis suggestive of CSD. Serology was not available for this case.