High-level adenovirus-neutralizing antibodies plasma beneficial for adenovirus type 7 (Adv7) induced pediatric severe...

Respiratory failure and acute respiratory distress syndrome (ARDS) caused by adenovirus pneumonia (AVP) present significant challenges for pediatricians. High-level adenovirus-neutralizing antibody plasma (HL-ANAP), containing elevated levels of neutralizing antibodies (NAbs), might represent a valuable passive immunotherapy option. To assess the therapeutic effects, we investigated three cases diagnosed with adenovirus type 7 (Adv7)-induced severe ARDS, which required combined therapy with extracorporeal membrane oxygenation (ECMO) and HL-ANAP.

Blood samples from three patients with Adv7-induced ARDS were collected before HL-ANAP administration, and at 6, 12, 24, 48, and 72 hours, and 7, 21, and 28 days after treatment. We measured Adv7 viral load, NAb titers, and cytokine levels in the serum, describing the observed trends.

All patients survived. Before HL-ANAP transfusion, Adv7 viral loads exceeded 1∗10^7. Adv7 viral loads gradually decreased within 72 hours after HL-ANAP transfusion, accompanied by a rising trend in NAb titers. IL-6 and IL-8 levels decreased sharply during the first 24 hours post-HL-ANAP transfusion, followed by a slower decline.

HL-ANAP may be effective in treating ARDS induced by severe type-7 adenoviral pneumonia in children. This approach may reduce adenovirus load, decrease systemic inflammation, and improve clinical outcomes. The neutralizing antibody's activity against the virus may occur within 24-72 hours post-infusion in vivo.