Case of the Month - April 2020
A 56-year-old woman with dermatomyositis and monoclonal gammopathy of unknown significance developed painful erythematous nodules of the left elbow, right proximal arm, and left upper thigh. They were was preceded by development of left leg swelling and erythema. The symptoms were initially thought to be a flare of her dermatomyositis, and as a result, her prednisone dose was increased. However, the dermal nodules remained unchanged.
She had some intermittent chills that she attributed to the prednison, but no night sweats, cough, or hemoptysis. There was no drainage from the nodules. There was no preceding trauma to any of the areas where the nodules developed, but she said that she had returned from a trip to Belize immediately prior to their development.
A punch biopsy was performed by Dermatology and the stained sections are shown below. Nothing grew, but an organism was was identified by broad-range 16S ribosomal PCR performed at the CDC. Typical growth for this organism occurs at a lower temperature (28-32 C) than most other members of this genus, requires media supplemented with heme, and usually takes at least 4 weeks.
What is it?
Low-power view of one of the punch biopsy lesions, stained with H&E.
High-power view of one of the punch biopsy lesions, stained with H&E.