Unilateral thoracic eruption

Presented by Makayla Powers, PA-C

HPI: The patient is a 4 year old girl who presents with her parents for a skin eruption. Her parents state this has been present for about 2 months now. This eruption started as one erythematous patch on the left flank. The area started to resolve after a few days, however it then worsened again. She saw her pediatrician who suspected this was ringworm and she was prescribed clotrimazole. They used the clotrimazole for a couple weeks, however the rash continued to worsen and spread. They then started using mupirocin ointment, without significant improvement. She was then prescribed triamcinolone cream to use in addition to the mupirocin and she has been using both of these without any resolution. Around a month ago the patient was started on cephalexin which also was did not cure the rash. The eruption is asymptomatic. 

Her mother notes prior to onset of this eruption, patient had COVID and two ear infections which required two rounds of antibiotics. 

They have two cats, two bunnies and one dog at home. No one else in the household has a rash. 

Physical exam: On exam, patient has multiple erythematous circular patches on the left flank extending to the back and chest, with some newer lesions have vesicles and are in a zosteriform distribution. She has an erythematous macule as well as an erythematous papule on the left upper outer arm. 

Here is a picture of the rash from a couple weeks ago:

Because of the diagnostic uncertainty, a punch biopsy was done.

Pathology:
Photomics are courtesy of dermatopathologist, David Jones, Berkshire Medical Center

The biopsy shows perifollicular inflammation

 and PASD stain shows spores in the hair follicles.

Diagnosis:  Fungal folliculitis, endothrix.  This is not Majocchi's granuloma yet, but may be moving in that direction.

Plan:

A fungal culture was taken from skin scrapings and the patient was started on terbinafine 125 mg daily.  We plan to keep her on it for 6 weeks.

Reference
Majocchi's granuloma: current perspectives. Infect Drug Resist. 2018 May 22;11:751-760.  PMC Free Full Text.  Note: The English is not good, but the article is comprehensive.  There are no comparable reviews of MG.