2025 – PAGE 156 – DERMATOLOGY

HYPOHIDROTIC ECTODERMAL DYSPLASIA

Hypohidrotic ectodermal dysplasia is a condition related to INCONTINENTIA PIGMENTI, but this can occur in boys. It is associated with HYPOHIDROSIS, decreased sweating, which can lead to hyperthermia; HYPOTRICHOSIS, sparse hair, so no eyebrows/lashes; DELAYED TOOTH ERUPTION; and DEFORMED/PEG TEETH.

IMAGE: www.pbrlinks.com/HED1
IMAGE: www.pbrlinks.com/HED2

INFECTIOUS SKIN CONDITIONS

(DOUBLE TAKE) ECTHYMA GANGRENOSUM

Ecthyma gangrenosum is usually a sign of a PSEUDOMONAS infection and possibly sepsis in an immunocompromised patient, especially LEUKEMIA! Look for a neutropenic patient with black, necrotic, ulcerative lesions with surrounding erythema and edema. These lesions are often located in the groin/diaper area.

IMAGE: www.pbrlinks.com/ECTHYMA1

STREPTOCOCCAL INFECTIONS OF THE GROIN

Streptococcal infections of the groin or perineum are associated with pain with stooling, pruritis, redness, and possibly a fissure. Unlike zinc deficiency, there is no desquamation. If vaginal or vulvovaginitis, look for a history of vaginal discharge. Diagnose by culturing the area. Treat with amoxicillin, penicillin (PCN), or a first generation cephalosporin. Risk factors include abuse and previous instrumentation. Look for a history of recent antibiotics in case the discharge is due to Candida.

(DOUBLE TAKE) CUTANEOUS CANDIDIASIS, A DIAPER DERMATITIS

Cutaneous candidiasis, a diaper dermatitis, can occur secondary to a contact dermatitis or recent antibiotic use. It presents as a beefy red rash with papular satellite lesions. This rash goes into the inguinal folds. Use a KOH prep to confirm diagnosis, and treat with a topical antifungal, such as nystatin or clotrimazole.

IMAGE (includes satellite lesions): www.pbrlinks.com/CUTASCAN1

BULLOUS IMPETIGO/STAPH SCALDED SKIN SYNDROME (SSSS)

Bullous impetigo, or Staph Scalded Skin Syndrome (SSSS), is a spectrum of the same disease.

• IMPETIGO: Look for honey-colored crusting lesions and bullae. Non-bullous impetigo will look similar but without vesicle/bullae (more oozing/crusting).
  • IMAGE: www.pbrlinks.com/SSSS1
  • IMAGE: www.pbrlinks.com/SSSS2
  • IMAGE: www.pbrlinks.com/SSSS3
• SSSS: A very painful and red rash in which large, thin blisters are the result of an exotoxin. There is “sheet-like” skin loss/separation. This looks very superficial compared to impetigo. Obtain a BIOPSY to prove that it is SSSS and NOT Stevens-Johnson Syndrome (SJS) or Toxic Epidermal Necrolysis (TEN), both of which have deeper/dermal involvement.
  • IMAGE: www.pbrlinks.com/SSSS2
  • PEARL: Lesions are NOT in the eyes or mouth but may be around the eyes and mouth (as opposed to SJS/TEN, which may be IN the eyes and mouth).