Presenter: Riddhi Shah, DO
Dermatology Program: MSUCOM/Lakeland Regional Medical Center
Program Director: Mark A. Kuriata, DO, FAOCD
Submitted on: October 31, 2014
CHIEF COMPLAINT: Tender bumps on the lower legs x 8 weeks
CLINICAL HISTORY: An 18-year-old Caucasian female presented to the clinic with complaints of tender bumps on the lower legs for 8 weeks. Bumps were initially were red in color and then changed to a more purplish hue. The patient denied any joint aches, oral contraceptive use or pregnancy, new medications, or recent trauma/bug bite. Prior treatment included topical corticosteroid cream prescribed by her family doctor, which proved ineffective. Of note, the patient had a history of recent untreated sore throat and cough.
PHYSICAL EXAM:
A full skin exam revealed erythematous and violaceous 2-4 cm smooth deep-seated nodules scattered on the bilateral pretibial areas.
LABORATORY TESTS:
CBC with differential: within normal limits
CRP: 2.7
ESR: 28
ASO titer: 109
Lyme Antibodies: 0.43
DERMATOHISTOPATHOLOGY:
Double punch biopsies were obtained on the right and left distal shin. Histopathology revealed mature lipocytes with inflammation and fibrosis of the septal structures. The dominant cell infiltrate are histiocytes with some admixed lymphocytes and giant cells. The overlying epithelium revealed an irregularly acanthotic epidermis.
DIFFERENTIAL DIAGNOSIS:
1. Erythema Nodosum
2. Erythema Induratum
3. Arthropod Assault
4. Hypersensitivity Reaction
5. Subcutaneous Granuloma Annulare