Acute renal cortical necrosis due to acquired antiprotein S antibodies

Abstract

Although varicella is a common disease of childhood, renal complications are quite rare. We report here the interesting case of a-22 month-old boy exhibiting renal cortical necrosis related to an acquired protein S deficiency following varicella. Ten days after the vesicle eruption appearance, he presented with ecchymosed heels, oligoanuric kidney failure, anemia [hemoglobin (Hb) 78 g/L], schizocytosis (2.5%), but normal platelet count. Kidney sonography and magnetic resonance imaging evoked renal cortical necrosis. All together, these features suggested acquired protein S deficiency secondary to varicella. Strikingly, it was confirmed by a dramatic decrease in protein S plasma activity and a huge increase in immunoglobulin (Ig)G antibodies against protein S in the plasma. Anticoagulation therapy in addition with plasmapheresis and steroid pulses allowed a dramatic decrease in the antibodies against protein S and recovery of normal protein S activity. Undelayed diagnosis and treatment did not avoid kidney insufficiency but prevented life-threatening complications. In the light of this case report, protein S deficiency due to antibody inhibition should be carefully monitored anytime in the context of varicella when kidney insufficiency or necrosis occurs.

Novel management of post varicella purpura fulminans owing to severe acquired protein S deficiency

“…Alternative treatments that have been used include steroids and intravenous (i.v.) immunoglobulin because of their potential 'antibody blocking' activity [1][2][3][4][8][9][10][11]. In many cases a combination of all of the above are used.…”

“…Previous treatment options for acquired protein S deficiency have focused on either replacing the protein S or removing the antibody [1][2][3][4][8][9][10][11]. Attempts at replacing protein S with fresh frozen plasma are rarely successful because of the small amounts of protein S in frozen plasma and the ability of the antibody to bind to protein S, thus enhancing its clearance from the circulation [1].…”

Idiopathic purpura fulminans associated with anti-protein S antibodies in children: a multicenter case series and systematic review

“…Hence, IPF treatment must be effective to prevent the occurrence of thrombosis and to eliminate the antibody. In the literature, heparin anticoagulation and FFP infusion are the most used treatments, while the effectiveness of immunoglobulin infusions and plasmapheresis to decrease the inhibitor has been suggested in several case reports 2,12,20 . In our study, the AT level and platelet count at diagnosis appeared to be associated with severe complications.…”

Is complement a culprit in infection-induced forms of haemolytic uraemic syndrome?

“…One patient had an underlying MCP mutation, and interestingly, another patient was shown to have anti-CFH antibodies ). Infection with VZV is known to induce anti-protein S and antiphospholipid antibodies (Larakeb et al 2009) and in a similar way, VZV may trigger autoimmunity in patients with a genetic susceptibility linked to CFHR1/CFHR3 deletion. Perhaps there is a degree of cross-reactivity between VZV antigen and CFH protein, but the presence of CFHR1 and/or 3 protects from anti-CFH antibody formation.…”