Sex: F
Vaccine: FLUX
Symptoms: Immunology test, Leukocytosis, Pemphigoid, Pruritus, Skin disorder
Clinical narrative: Bullous pemphigoid (BP) in infancy; pruritic on the trunk, extremities, palms and soles; vesicles and bullae on the trunk, extremities, palms and soles; Initial information received on 14-Aug-2021 regarding an unsolicited valid serious case issued from a literature article via Physician.   This case involves a five-month-old female patient who experienced symptoms of pruritic on the trunk, extremities, palms and soles (pruritus) and vesicles and bullae on the trunk, extremities, palms and soles (blister) and was diagnosed with Bullous Pemphigoid (BP) in infancy (pemphigoid), while receiving INFLUENZA VACCINE.  The patient's medical history, past medical treatments, vaccinations and family history were not provided.   On an unknown date, the patient received a dose of suspect INFLUENZA VACCINE produced by unknown manufacturer batch number and expiry date not reported via an unknown route in unknown administration site for prophylactic vaccination.  On an unknown date, the patient experienced serious symptoms of pruritic on the trunk, extremities, palms and soles (pruritus) and vesicles and bullae on the trunk, extremities, palms and soles (blister) five days following the administration of INFLUENZA VACCINE.   On an unknown date, the patient was diagnosed with bullous pemphigoid (BP) in infancy (pemphigoid) (serious event, unknown latency) following the administration of INFLUENZA VACCINE.   These events were assessed as medically significant.  Laboratory work-up revealed a leukocytosis with peripheral eosinophilia (White Blood Cells (WBC) count: 30.5 cells/mm3, eosinophils count: 24 percent). Lesional skin biopsy demonstrated a subepidermal blister with numerous eosinophils.  Direct immunofluorescence (DIF) of perilesional skin showed linear deposition of Immunoglobulin G (IgG) and C3 along the dermo epidermal junction. Bullous pemphigoid (BP) 180 Enzyme-linked immunosorbent assay (ELISA) was positive (Bullous pemphigoid (BP) 180 more than 100).  She was started on systemic steroids (Prednisolone 2 mg/kg/day) for Pemphigoid. Skin findings significantly improved within two days. She remained in remission while tapering off Prednisolone.  Discussion: Bullous pemphigoid (BP) should be considered in infants with tense bullae, particularly when there is involvement of the palms and soles. Numerous cases had been reported in association with recent vaccinations. Some authors posit vaccines might unmask subclinical Bullous pemphigoid (BP) by inducing a nonspecific immune activation, while others believe the trauma from injection could generate T helper 17 (Th17) cell activation and release of proinflammatory cytokines, leading to bullae formation. Diagnosis was confirmed with biopsy for Hematoxylin and Eosin (H and E) and DIF, and anti-Bullous pemphigoid (BP) 180 ELISA. Infantile Bullous pemphigoid (BP) was often self-limited with a benign course. Localized disease (less than 10 percent Body Surface Area (BSA) and Bullous pemphigoid (BP) 160 less than 100U/L) was treated with topical steroids, while cases with extensive involvement might require systemic therapy.  At time of reporting, the patient was recovering from the events.  Information on the batch number was requested for this case.; Sender's Comments: This case concerns a five-month-old female patient who experienced symptoms pruritic and vesicles and bullae on the trunk, extremities, palms and soles (latency: 5 days) and was diagnosed with Bullous Pemphigoid (BP) (latency unknown), after receiving INFLUENZA VACCINE produced by unknown manufacturer. The time to onset is compatible with the symptoms and is unknown for the diagnosed event. The patient's lab tests included White Blood Cells (WBC) count: 30.5 cells/mm3, eosinophils count: 24 percent, Lesional skin biopsy demonstrated a subepidermal blister with numerous eosinophils, Direct immunofluorescence (DIF) of perilesional skin showed linear deposition of Immunoglobulin G (IgG) and C3 along the dermo epidermal junction. Bullous pemphigoid (BP) 180 Enzyme-linked immunosorbent assay (ELISA) was positive. There is no information regarding patient's medical history and medical condition. Based upon the reported information, the role of the suspect vaccine cannot be assessed.