case_images: PMC11813044_01
case_images: Clinical pictures of the lesion. (A) Erythematous nodule and superficial ulceration with exudate and edema, no obvious crust, pus or blisters. (B) After more than 20 d of topical application of compound polymyxin B ointment, the ulceration healed, covered with yellow scabs.
case_images: medi-104-e41450-g001.jpg
case_images: PMC11813044_01_medi-104-e41450-g001.jpg
case_images: F1
case_images: A single erythematous 4 cm x 5 cm nodule and painful superficial ulceration companied by exudate and edema was found on the right hip without elevated skin temperature, obvious pus or blisters (Fig. 1A). At this time, the ulceration on the lesion was healed and covered with yellow scab (Fig. 1B).
case_images: Pictures of microbiological and histopathological results. (A) Tissue smear showed multiple acid-fast bacilli (in Ziehl-Neelsen staining). (B) Yellow colonies of Mycobacterium avium on the modified Lowenstein-Jenson medium. (C) Hyperkeratosis, parakeratosis, neutrophil abscess in the corneum, hyperplasia and hypertrophy in the spinous layer, irregular proliferation of dermal processes (40x, in HE staining). (D) Infiltration of mixed inflammatory cells including histiocytes, lymphocytes, neutrophils, and multinucleated giant cells in the superficial dermis with dense and parallel arrangement of dermal collagen fibers around (200x, in HE staining). HE = hematoxylin-eosin.
case_images: medi-104-e41450-g002.jpg
case_images: PMC11813044_01_medi-104-e41450-g002.jpg
case_images: F2
case_images: However, Ziehl-Neelsen stain of the smear showed acid-fast bacilli (Fig. 2A). During the hospitalization, culture on the modified Lowenstein-Jenson medium at 28 C produced yellow colonies (Fig. 2B), which was further identified as M avium by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF).
case_images: Preoperative and postoperative pictures of the granuloma. (A) B-ultrasound showed the hypoechoic structure with clear boundary under the lesion. (B) The excised granuloma and surrounding adipose connective tissue. (C) After 1 mo, the patient showed no fluid sonolucent area or new hypoechoic structure under the lesion.
case_images: medi-104-e41450-g003.jpg
case_images: PMC11813044_01_medi-104-e41450-g003.jpg
case_images: F3
case_images: After assessing the depth of involvement using B-ultrasound (Fig. 3A), the granuloma and surrounding adipose connective tissue were surgically removed for debridement (Fig. 3B). One month later, B-mode ultrasound detected no fluid sonolucent area or new hypoechoic structure (Fig. 3C).