Systemic capillary leak syndrome induced by influenza type A infection

Abstract

A 42-year-old man visited the emergency department complaining of lower extremity swelling and myalgia. His influenza A antigen test was positive, and he was admitted for supportive care of severe myalgia. On the first hospital day, the swelling in his lower legs was aggravated with intolerable pain, and his creatine phosphokinase and hemoglobin levels were elevated. He was treated with massive hydration, albumin replacement, continuous venovenous hemofiltration, phlebotomy, and oseltamivir. The swelling and pain in his extremities were decreased without renal dysfunction, even though peripheral neuropathy and muscular complication persisted. Systemic capillary leak syndrome is a rare but life-threatening condition. The diagnosis is made clinically based on a classic triad of hypotension, hypoalbuminemia, and hemoconcentration. In our case, the influenza A infection was related to the capillary leakage.

Keywords: Capillary leak syndrome; Edema; Hypoalbuminemia; Influenza A virus; Rhabdomyolysis.

Fig. 1.

Computed tomography angiography of the lower extremities before the acute phase. The arterial systems of both lower extremities are grossly normal without remarkable stenosis or obstruction. There is no evidence of deep vein thrombosis in either lower extremity. Mild subcutaneous edema is observed in both lower legs.

Fig. 2.

T2-weighted magnetic resonance imaging of the lower extremities in the late phase. The anterior, lateral, and deep posterior compartments of both calf muscles are swollen, and the signal intensity is increased. Inner compartment enhancement is not observed, but the fascia rim is enhanced. The superficial posterior compartment shows mild swelling, and signal intensity is increased heterogeneously. There is patchy enhancement in the superficial posterior compartment.