Dermatologic disorders

Blistering Distal Dactylitis

Nirav Shastri, MD
Milton A. Fowler, Jr., MD, MPH
Bhavin Doshi, MD
Volume 13 - Issue 2 - February 2014

A 13-month-old boy presented to a pediatric emergency department with a painful blister on the right great toe. The blister had been rapidly enlarging over the previous several hours and was preceded by an initial red rash a day earlier. The blister initially had contained clear fluid and later developed a darker color.

There was no discharge from the blister. There was no history of local trauma, fever, previous skin infection, or contact with anyone with a skin infection.

Physical examination revealed a nontoxic, afebrile infant with an approximately 2.5-cm diameter, solitary, hemorrhagic, tense bulla on the ventral aspect of the distal right great toe. There was no surrounding erythema. Systemic physical examination findings were otherwise unremarkable.

The lesion was incised and drained under local anesthesia, yielding a moderate amount of hemorrhagic purulent fluid. Culture specimens grew methicillin-sensitive Staphylococcus aureus. The child received a diagnosis of blistering distal dactylitis, was discharged on a regimen of oral cephalexin, and experienced no recurrence.

Blistering distal dactylitis is a localized infection of the volar fat pad of the distal phalanx of digits, usually presenting as a fluid-filled blister. The causative organisms in most cases are group A β-hemolytic streptococci, although S aureus (including methicillin-resistant strains1) and Staphylococcus epidermidis also have been isolated.

Typical age of incidence of blistering distal dactylitis is from 2 to 16 years, but it also has been reported in younger patients and in immunocompromised adults. Systemic manifestations are rare.

The differential diagnosis includes bullous impetigo, herpetic infection, traumatic blisters, burns, and epidermolysis bullosa. Treatment entails drainage of the lesion followed by administration of oral antibiotics.

Reference:

1. Fretzayas A, Moustaki M, Tsagris V, Brozou T, Nicolaidou P. MRSA blistering distal dactylitis and review of reported cases. Pediatr Dermatol. 2011;28(4):433-435.