Case Report of Subcutaneous Nodules and Sterile Abscesses Due to Delayed Type Hypersensitivity to Aluminum-Containing Vaccines.

Routine childhood immunizations have resulted in great reductions in vaccine-preventable infectious diseases. Vaccine-related adverse events, albeit rare, can be of significant consequence. Although anaphylaxis, or type I hypersensitivity, is recognized as a potential reaction after vaccination, delayed type hypersensitivity or type IV reactions are less so. We present a case of persistent subcutaneous nodules and sterile abscesses in the setting of delayed type hypersensitivity to aluminum, confirmed by patch testing and recurrence on re-exposure. We review sources of aluminum in common immunizations, principles for treatment, and strategies for management of future vaccinations for this patient.