CASE REPORT
A 46-year-old African-American female with HIV disease
presented to clinic 7 weeks following the onset
of a diffuse, highly pruritic rash. The rash developed
one day following her annual influenza vaccination, which she
had received in the past without incident. She noted no history
of previous reaction to drugs or vaccinations of any kind. Her
medications included efavirenz, lamivudine and zidovudine.
On physical exam, the patient had a diffuse eruption of hyperpigmented,
slightly violaceous polygonal papules and plaques
with white, lacy reticulations that spared her face, palms, and
soles (Figure 1). No changes were noted on the buccal mucosa.
CD4 count one month prior to vaccination was normal at 706
cells/mcL. Viral load was suppressed at 128 copies/nL.
Histopathology revealed a lichenoid interface dermatitis with eosinophils,
most consistent with lichenoid drug eruption (Figure 2).
Immunohistochemical stain for Treponema pallidum was negative.
The patient was treated with high potency topical corticosteroids,
two oral prednisone tapers, and narrow band UVB therapy. While
therapy was being initiated, the lesions progressed to include the
face. Narrow band UVB therapy and clobetasol ointment were
continued, and metronidazole 500 mg PO BID and topical tacrolimus
0.1% ointment were added to the regimen. Approximately
6 months after initiating therapy, all active lesions had resolved
with marked post-inflammatory hyperpigmentation.
DISCUSSION
Literature review of lichenoid drug reactions to influenza vaccination
revealed only four reported cases. The first case described
histologically confirmed generalized lichen planus (LP) occurring
seven days following intramuscular injection with an inactivated
influenza vaccine. Lesions began on the volar forearms and
evolved to include the arms, trunk, and lower extremities.1 A subsequent
case series described linear lesions following the lines
of Blaschko in two cases and oral LP in a third, each occurring
within two weeks of vaccination. In contrast to the first described
case and this present case report, in which the patients developed
diffuse reactions, the lesions described in this case series
were localized to the left leg, left buttock and leg, and oral mucosa
respectively.2 Although the reactions in all reported cases
developed within one day to two weeks following vaccination,
the spectrum of involvement varied significantly.
While rare lichenoid reactions to Tdap and combined MMRDTaP-
IPV have been documented, 3 the greatest proportion of
such reactions following vaccination have been attributed to
the HBV vaccine.4-6 In one such case, a few days following his
third HBV vaccination, a 13 year old Hispanic male developed
pruritic, polygonal papules and plaques, erythematous to violaceous
in color, with distinct raised borders. Similar to our case,
the lesions spread diffusely, involved the face, and spared the
mucous membranes. A lichen planus type eruption was confirmed
via histology.7 Consistent with time of onset following
documented lichenoid reactions to HBV vaccination, the eruption
presented in this current case report occurred just one day
following influenza vaccination.
Review of the components of the HBV vaccine8 and the seven
influenza vaccines9 available during the 2011-2012 influenza
season revealed one common ingredient, thimerosal, which
has been implicated in reactions secondary to both influenza
