Age: 89.0
Sex: F
Vaccine: FLUX, FLUX
Symptoms: Thrombocytopenia, Urine analysis normal
Clinical narrative: This Literature - Spontaneous case, initially received on 30-Aug-2016, was reported by a health professional and concerns an 89-year-old female patient. Weight: not provided; Height: not provided. Past medical history included well-controlled diabetes mellitus, hypertension and paraproteinemia. Administration of company suspect drug(s): On an unknown date, the patient received influenza vaccine for vaccination. Dose regimen: Not reported. Route: Not reported. Batch number: Not reported. No additional suspect drugs. Adverse reactions/events and outcomes: On an unknown date, the patient presented with a 3-day history of a pruritic eruption on the legs. On examination, she had non-blanching erythematous-to-violaceous macules that coalesced into patches, in addition to palpable purpura, on the bilateral lower extremities. She otherwise felt well and denied fever, chills, dysuria, nausea, vomiting, abdominal pain, or upper respiratory symptoms. She denied taking new medications. Biopsy findings from a purpuric papule on the thigh were consistent with leukocytoclastic vasculitis. Complete blood count showed mild anemia and thrombocytopenia. Urinalysis result was within normal limits. Without an obvious infection or medication trigger, the patient's history of paraproteinemia was suspected as a possible inciting factor. The hematology department determined that there was a possibility of lymphoma; however, the patient was otherwise asymptomatic and elected to monitor rather than intervene. Five days after initial presentation, the eruption was markedly improved, with predominantly post-inflammatory hyperpigmentation remaining. Complete resolution occurred within 3 weeks. One year later, the patient presented with a recurrence of scattered erythematous non-blanching macules and palpable purpura on the bilateral lower extremities. Similar to the previous episode, review of systems was otherwise negative. She denied taking new medications or having recent infection. Complete blood count showed mild pancytopenia. Urinalysis result was within normal limits. During the interim, the patient had undergone radiologic imaging and had no evidence of a clinically significant lymphoma. She showed no sign of systemic involvement. Chart review revealed that the patient had received the influenza vaccine 11 days before the onset of the current eruption. Upon further investigation, it was discovered that the patient also received the influenza vaccine 11 days before the onset of the initial eruption 1 year before. The patient had not started any other medications before either incident. She had a history of paraproteinemia, without evidence of clinically significant lymphoma on recent imaging. The final diagnosis is suspected to be LCV secondary to the influenza vaccine, given the identical onset of the episodes 11 days after vaccination and complete resolution between the 2 exposures. The patient was counselled to avoid the influenza vaccine next year. Reporter's comments: The authors reported that leukocytoclastic vasculitis caused by influenza virus infection has been reported in several previous cases. Similar to this case, most of these patients were elderly with onset of the eruption 7 to 14 days after administration of the influenza vaccine. The temporal nature of these cases of vasculitis following vaccination suggests an immunopathogenic link that has yet to be explained. It is interesting to consider the role of paraproteinemia in this case. Although the timing of the patient's episodes of LCV provides strong support for the vaccine's role, we must consider the possibility that an underlying paraproteinemia may have made the patient more susceptible to the eruption. Sender's Comments: Company comments and assessment: Listedness: The events of vasculitis and thrombocytopenia assessed as listed as per product. The rest of the events are unlisted. Causality: The events are assessed as related, given the temporal relationship as well as considering the recurrence of symptoms at rechallenge. The patient history of diabetes mellitus and paraproteinemia, as well as any therapies associated with these conditions cannot be excluded as potentially contributory to the response to the influenza vaccines.