title: Severe autoimmune protein S deficiency in a boy with idiopathic purpura fulminans.
abstract: Idiopathic purpura fulminans usually occurs in young children and is frequently preceded by a preparatory viral or bacterial infection. Following a severe streptococcal pharyngitis, an 8-year-old boy developed purpura fulminans with disseminated intravascular coagulation and severe protein S deficiency (total antigen < 0.05 u/ml). Despite generous plasma infusions, skin necrosis progressed rapidly into compartment syndrome which required fasciotomy and skin grafting and resulted in the loss of three digits of the right foot. Total protein S remained low for over a month despite plasma supplementation and complete normalization of protein C levels. A polyclonal anti-protein S IgG was demonstrated in the patient's plasma, which decreased to 25% of baseline titre after 1 month and was undetectable 6 months after purpura fulminans, when plasma protein S had returned to normal. Transient, isolated and severe deficiencies of protein S have been reported in patients with idiopathic purpura fulminans and a previous preparatory infection. Autoimmune protein S deficiency may play a key role in the aetiopathogenesis of idiopathic purpura fulminans.
authors.affiliation: Medical School of Hannover, Children's Hospital, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Bergmann
authors.forename: P F
authors.initials: PF
authors.lastname: Hoyer
authors.forename: S V
authors.initials: SV
authors.lastname: D'Angelo
authors.forename: G
authors.initials: G
authors.lastname: Mazzola
authors.forename: C
authors.initials: C
authors.lastname: Oestereich
authors.forename: M
authors.initials: M
authors.lastname: Barthels
authors.forename: A
authors.initials: A
authors.lastname: D'Angelo
mesh_terms: D001323:Autoantibodies / Q000097:blood; D001327:Autoimmune Diseases / Q000150:complications*; D002648:Child; D004211:Disseminated Intravascular Coagulation / Q000209:etiology; D006801:Humans; D011695:IgA Vasculitis / Q000209:etiology*; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D009336:Necrosis; D010612:Pharyngitis / Q000150:complications*; D011486:Protein C / Q000378:metabolism; D017293:Protein S / Q000276:immunology; D018455:Protein S Deficiency / Q000150:complications*; D012867:Skin / Q000473:pathology; D013290:Streptococcal Infections / Q000150:complications*
chemical_list: D001323:Autoantibodies; D007074:Immunoglobulin G; D011486:Protein C; D017293:Protein S