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

Thrombosis in the perforasome in idiopathic purpura fulminans with anti-protein S antibodies: Anatomical and clinical evidence to improve management

Idiopathic purpura fulminans (IPF) is a rare and severe form of purpura fulminans caused by acquired protein S deficiency. It can lead to severe thrombotic complications, such as large skin necrosis and amputation. The lesions almost exclusively affect the lower limbs, and their distribution is similar among patients with IPF, unlike classical purpura fulminans lesions. Our hypothesis is that vascular structures called perforasomes may be involved in IPF, possibly caused by protein S deficiency. We analyzed all case reports and case series published in the literature that provided sufficient data for an anatomical study of limb injuries. For precise localization of areas of necrosis, we examined each case using descriptions and images to determine whether they overlapped with vascular territories that include perforasomes. We analyzed twelve cases from the literature and identified six vascular territories: the anterolateral, anteromedial, and posterior territories of the upper leg, as well as the anterolateral, anteromedial, and posterolateral territories of the lower leg. For each territory, we described the most probable vascular damage and the corresponding perforasome. IPF is a complex multifactorial disease in which a direct involvement of perforating arteries may be suspected and taken into account in the surgical of lesions.

Limb Ischemic Necrosis Secondary to Microvascular Thrombosis: A Brief Historical Review

Ischemic limb injury can be broadly classified into arterial (absent pulses) and venous/microvascular (detectable pulses); the latter can be divided into two overlapping disorders-venous limb gangrene (VLG) and symmetrical peripheral gangrene (SPG). Both VLG and SPG feature predominant acral (distal) extremity ischemic necrosis, although in some instances, concomitant nonacral ischemia/skin necrosis occurs. Historically, for coagulopathic disorders with prominent nonacral ischemic necrosis, clinician-scientists implicated depletion of natural anticoagulants, especially involving the protein C (PC) system. This historical review traces the recognition of natural anticoagulant depletion as a key feature of nonacral ischemic syndromes, such as classic warfarin-induced skin necrosis, neonatal purpura fulminans (PF), and meningococcemia-associated PF. However, only after several decades was it recognized that natural anticoagulant depletion is also a key feature of predominantly acral ischemic microthrombosis syndromes-VLG and SPG-even when accompanying nonacral thrombosis is not present. These acquired acral limb ischemic syndromes typically involve the triad of (a) disseminated intravascular coagulation, (b) natural anticoagulant depletion, and (c) a localizing explanation for microthrombosis occurring in one or more limbs, either deep vein thrombosis (helping to explain VLG) or circulatory shock (helping to explain SPG). In most cases of VLG or SPG there are one or more events that exacerbate natural anticoagulant depletion, such as warfarin therapy (e.g., warfarin-associated VLG complicating heparin-induced thrombocytopenia or cancer hypercoagulability) or acute ischemic hepatitis ("shock liver") as a proximate factor predisposing to severe depletion of hepatically synthesized natural anticoagulants (PC, antithrombin) in the setting of circulatory shock.

Protein S Deficiency: A Case Report

Protein S is a glycoprotein created by the body that aids in the prevention of a hypercoagulable state. Protein S-deficient patients are placed on anticoagulant regimens, as there is no current definitive cure. Failure to bring balance to the hematological system in these patients will lead to complications such as widespread clot formation and pulmonary embolisms. Here, we present a 74-year-old female who was admitted to the ICU after collapsing. She presented with respiratory failure, urinary tract infection (UTI), and pneumonia. Magnetic resonance imaging (MRI) scans depicted a thrombus in the distal right transverse sinus and sigmoid sinus. Her hematologic workup showed normal levels of homocysteine, fibrinogen, and protein C levels but protein S levels were reduced to 24%. This case displays the intricate presentation of a rare hematological disease as well as the importance of routine follow-up to maintain patient health.

Post-viral idiopathic purpura fulminans is associated with inherited thrombophilia and anti-cardiolipin antibodies

Introduction

Idiopathic purpura fulminans (IPF) is a rare and severe coagulation disorder, associated with transient anti-protein S (anti-PS) antibodies in the context of post-viral infection such as varicella. Anti-protein S antibodies are frequently found in the context of varicella, in contrast with the rarity of IPF. Other factors such as anti-phospholipid antibodies (APL) and inherited thrombophilia may be associated with severe vascular complication.

Method

This is an ancillary study of a French multicenter retrospective series and systematic review of literature. We analyzed patients who were tested for inherited thrombophilia, namely antithrombin, protein C, protein S deficiency; prothrombin gene G20210A polymorphism (FII:G20210A),Factor V R506Q polymorphism (FV:R506Q); and/or for APL (lupus anticoagulant (LA), anti-cardiolipin antibodies (ACL), or anti-beta 2-GPI antibodies (Aβ2GP1).

Results

Among the 25 patients tested for inherited thrombophilia, 7 (28%) had positive results. Three had FV R506Q, two FII:G20210A, one compound heterozygote FV:R506Q associated to FII:G20210A, and one protein C deficiency. APL testing was performed in 32 patients. It was positive in 19 patients (59%): 17 ACL (53%), 5 LA (16%), 4 Aβ2GP1 (13%). The risk of severe complications was not associated with presence of inherited thrombophilia or APL presence, with RR: 0.8 [95% CI: 0.37-1.71], p = 1 and RR: 0.7 [95% CI: 0.33-1.51], p = 0.39, respectively. We found a high prevalence of inherited thrombophilia or APL in a population of patients with IPF. However, we do not find an association with the occurrence of severe vascular complications or venous thromboembolism.

Lower Limb Necrosis Secondary to Purpura Fulminans: A Case Report

Purpura fulminans is a rare and rapidly progressive septic process characterized by the development of hemorrhagic and ecchymotic lesions and skin necrosis. In this work, we report a case of a 52-year-old woman admitted to the Department of Emergency due to progressive purpura. The physical examination demonstrated a decreased skin temperature, unpalpable dorsalis pedis arteries, and ecchymoses covering both lower extremities. Laboratory tests indicated disseminated intravascular coagulation with prolonged activated partial thromboplastin time (APTT), low prothrombin time (PT), elevated d-dimer levels, and a low platelet count. A diagnosis of purpura fulminans was made, and steroids, therapeutic plasma exchange and empiric therapy, including antibiotic and anticoagulation therapy, were initiated immediately. Our treatment resulted in a good and sustained clinical response, as evidenced by the receding of blood blisters and the normalization of the patient's coagulation factors, but bilateral below-knee amputation was inevitable. Finally, the patient recovered well and was discharged home without any complications other than amputation.

Evaluation of post-infectious inflammatory reactions in a retrospective study of 3 common invasive bacterial infections in pediatrics

Infectious diseases can result in unanticipated post-infectious inflammatory reactions (PIIR). Our aim was to explore PIIR in 3 frequent pediatric bacterial invasive infections in France by a retrospective monocentric study. We included children hospitalized between 2003 and 2012 for Streptococcus pneumoniae (SP), Neisseria meningitidis (NM), or Streptococcus pyogenes invasive infections. The PIIR had to have occurred between 3 and 15 days without fever despite an individually tailored antibiotic therapy. A descriptive analysis was carried out to determine PIIR risk factors. We included 189 patients, of whom 72, 79, and 38 exhibited invasive infections caused by S pyogenes, SP, and NM, respectively. The mean age was 44 months. PIIR were observed in 39 cases, occurring after a median of 8 days (5-12), with a median duration of 3 days (2-6). Fever, arthritis, and pleural effusion were observed in 87%, 28.2%, and 25.6%, respectively. In multivariate analysis, PIIR were associated with pleuropneumonia, hospitalization in an intensive care unit (ICU), and elevated C-reactive protein (CRP). PIIR were observed in 20% of children after SP, NM, or S pyogenes invasives infections. Their occurrence was associated with the initial severity but not the etiological microorganism. Further studies are warranted to confirm these findings.