Postinfectious purpura fulminans caused by an autoantibody directed against protein S

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.

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.

Management of purpura fulminans skin loss at a regional burns centre: Sixteen-year experience

INTRODUCTION

Purpura fulminans (PF) is a rare syndrome of cutaneous purpura which is the consequence of severe circulatory shock causing intravascular thrombosis, haemorrhagic necrosis, and consequent tissue loss. The aim of this study was to present our 16-year experience of managing PF in a regional burns centre.

METHODS

We performed a single-centre retrospective case series of all patients admitted to the St Andrews Burns Centre at Broomfield Hospital, Chelmsford, Essex, UK, between June 2006 and July 2022 with a diagnosis of PF. Data were extracted by retrospectively searching hospital case notes.

RESULTS

Thirteen individuals were identified [five children (mean age 5, range 1-14) and eight adults (mean age 39, range 24-54)]. The total body surface area of cutaneous necrosis ranged from 5% to 80%, with a mean of 27.2%. Patients were treated with an established surgical sequence of total wound debridement and immediate coverage with a cadaveric allograft, followed by staged wound autografting. The mean time from disease onset to wound autografting was 37.3 days (range 20-64 days). Eight individuals (61.6%) required major amputation of at least one limb (proximal to the ankle or wrist joint). Only one mortality (of 80% total body surface area skin loss) was observed in the identified cohort.

CONCLUSIONS

The large body surface areas often involved in PF cases make management of these wounds well suited for burns centres, wherein established facilities and multidisciplinary teams exist that are familiar with managing large cutaneous burns. We provide a suggested algorithm to aid the management of PF.

Autoimmune complications of COVID-19 and potential consequences for long-lasting disease syndromes

The latest WHO report determined the increasing diversity within the CoV-2 omicron and its descendent lineages. Some heavily mutated offshoots of BA.5 and BA.2, such as BA.4.6, BF.7, BQ.1.1, and BA.2.75, are responsible for about 20% of infections and are spreading rapidly in multiple countries. It is a sign that Omicron subvariants are now developing a capacity to be more immune escaping and may contribute to a new wave of COVID-19. Covid-19 infections often induce many alterations in human physiological defense and the natural control systems, with exacerbated activation of the inflammatory and homeostatic response, as for any infectious diseases. Severe activation of the early phase of hemostatic components, often occurs, leading to thrombotic complications and often contributing to a lethal outcome selectively in certain populations. Development of autoimmune complications increases the disease burden and lowers its prognosis. While the true mechanism still remains unclear, it is believed to mainly be related to the host autoimmune responses as demonstrated, only in some patients suffering from the presence of autoantibodies that worsens the disease evolution. In fact in some studies the development of autoantibodies to angiotensin converting enzyme 2 (ACE2) was identified, and in other studies autoantibodies, thought to be targeting interferon or binding to annexin A1, or autoantibodies to phospholipids were seen. Moreover, the occurrence of autoimmune heparin induced thrombocytopenia has also been described in infected patients treated with heparin for controlling thrombogenicity. This commentary focuses on the presence of various autoantibodies reported so far in Covid-19 diseases, exploring their association with the disease course and the durability of some related symptoms. Attempts are also made to further analyze the potential mechanism of actions and link the presence of antibodies with pathological complications.

An Atypical Case of Idiopathic Purpura Fulminans

Idiopathic purpura fulminans (PF) is rare but has been reported in pediatric patients, commonly following infections. We present a case of a 5-year-old boy, heterozygous for factor V Leiden, with no history of recent infections, who presented with PF secondary to acquired protein S deficiency. Despite initial supportive treatment, the patient required surgical fasciotomy and extensive skin grafts. The protein S level normalized 4 months following the presentation. In this context, an autoimmune component with transient anti-protein S antibodies was believed to be involved. This case report highlights the course of idiopathic PF due to noninfectious acquired protein S deficiency.

A case of a young boy with hyper-fibrinolysis associated with natural fibrin precipitates suspected to have occurred through a novel coagulation and fibrinolysis mechanism

An 8-year-old Japanese boy with no underlying disease presented with severe intramuscular hematoma of the hip, and was admitted for a disseminated intravascular coagulation-like state with fibrinolytic dominance. Laboratory examinations revealed severe hyper-fibrinolysis with elevated markers, markedly shortened euglobulin clot lysis time, mildly decreased prothrombin, and severely decreased fibrinogen and factor XIII. Natural fibrin precipitates rapidly appeared in citrate-treated, ethylene-diamine-tetra-acetic-treated, and heparin-treated samples, but not in argatroban-treated samples, indicating that the mechanism of thrombin and fibrin formation was Ca²⁺-independent. The precipitates were physically similar to thrombin-triggered plasma fibrin. A global coagulation assay revealed that thrombin generation potentials were normal throughout the clinical course, whereas plasmin generation was already detected before initiation of fibrin formation in the acute phase. This phenomenon disappeared with time. Changes in coagulation abnormalities and nature of fibrinolysis paralleled those seen in specific markers for streptococcal infections. Streptokinase was possibly involved in this disease, as SDS-polyacrylamide gel electrophoresis revealed that plasmin derived from streptokinase-plasminogen complex proteolyzed the prothrombin to approximately 35-kDa α-thrombin consisting of the A-B single chain, which was identified by NH₂-terminal sequence analysis. The involvement of streptokinase-plasminogen-prothrombin caused by streptococcal infection may be one mechanism that produces marked hyper-fibrinolysis associated with natural fibrin precipitates.

A Rare Case of Purpura Fulminans in the Setting of Klebsiella pneumoniae Bacteremia

A 23-year-old man with circulatory shock associated with severe sepsis and congestive heart failure with an ejection fraction of 10% resulting in anasarca and multiorgan failure was admitted to our hospital's intensive care unit. Hours after admission, he developed a rash on his left inner thigh, which was later diagnosed as purpura fulminans (PF). Blood cultures were consistent with Klebsiella pneumoniae bacteremia, with community-acquired pneumonia being the possible source.

PF is a rare and difficult-to-diagnose entity characterized by dysregulated hemostasis that is often associated with poor prognosis and fatal outcomes. To our knowledge, there are limited reports in the literature on K. pneumoniae as a cause of PF. Given the rarity of this presentation, this case will serve as an opportunity to report and discuss the pathophysiology of this disease for the benefit of physicians.

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

Idiopathic purpura fulminans (IPF) is a rare but severe prothrombotic coagulation disorder that can occur after chickenpox or human herpesvirus 6 (HHV-6) infection. IPF leads to an autoantibody-mediated decrease in the plasma concentration of protein S. We conducted a retrospective multicenter study involving patients with IPF from 13 French pediatric centers and a systematic review of cases in published literature. Eighteen patients were included in our case series, and 34 patients were included as literature review cases. The median age was 4.9 years, and the diagnostic delay after the first signs of viral infection was 7 days. The lower limbs were involved in 49 patients (94%) with typical lesions. In all, 41 patients (78%) had a recent history of varicella-zoster virus infection, and 7 patients (14%) had been infected by HHV-6. Most of the patients received heparin (n = 51; 98%) and fresh frozen plasma transfusions (n = 41; 79%); other treatment options were immunoglobulin infusion, platelet transfusion, corticosteroid therapy, plasmapheresis, and coagulation regulator concentrate infusion. The antithrombin level and platelet count at diagnosis seemed to be associated with severe complications. Given the rarity of this disease, the creation of a prospective international registry is required to consolidate these findings.

Acute purpura fulminans-a rare cause of skin necrosis: A single-institution clinicopathological experience

BACKGROUND

Purpura fulminans, an uncommon syndrome of intravascular thrombosis with hemorrhagic infarction of the skin, is often accompanied by disseminated intravascular coagulation (DIC) and multi-organ failure, and may ultimately lead to death.

METHODS

Herein, we document 13 skin biopsies from 11 adult patients with the clinical diagnosis of sepsis and confirmed histopathologic diagnosis of intravascular thrombosis and/or DIC, compatible with acute infectious purpura fulminans (AIPF). Detailed history and clinical examination were performed, and the lesions were correlated with histopathologic findings. Any underlying medical disease was taken into consideration.

RESULTS

There were 5 males and 6 females with lower extremity or peri-incisional purpuric skin lesions. The most important comorbidities identified were a history of surgical procedure or neoplasm, although 4 patients had no relevant underlying history. Most skin biopsies revealed focal epidermal ischemia or necrosis and 3 showed full-thickness epidermal necrosis. In the underlying dermis, there were fibrin thrombi in superficial and deep blood vessels with acute inflammation. Changes of an inflammatory destructive vasculitis were identified in 5 cases. No bacteria or fungi were identified on histopathology.

CONCLUSIONS

AIPF is a rapidly-progressing medical emergency which may be identified by histopathology in culture-negative cases. Biopsies may show neutrophilic infiltrate without infective organisms.

Streptococcus pyogenes-purpura fulminans as an invasive form of group A streptococcal infection

BACKGROUND

Streptococcus pyogenes is an uncommon pathogen of purpura fulminans, and the pathogenesis of S. pyogenes-purpura fulminans remains unclear because of paucity of cases. We reported a pediatric case of S. pyogenes-purpura fulminans with literature review of the disease.

CASE PRESENTATION

A 3-year-old boy showed limping, lethargy and acral gangrene within 24 h. A diagnosis of S. pyogenes-purpura fulminans was made for bacterial isolation from throat and peripheral blood. Intensive therapy led to a survival with amputation of the left distal metatarsal bone, and normal development. The isolated M12 carried no mutation of csrS/R or rgg. Thrombophilia or immunodeficiency was excluded.

DISCUSSION

Twelve-reported cases (9 pediatric and 3 elderly) of S. pyogenes-purpura fulminans started with shock and coagulopathy. Five patients age < 8 years had no underlying disease and survived. One youngest and two immunocompromised patients died.

CONCLUSION

Streptococcus pyogenes-acute infectious purpura fulminans is a distinctive rare form of aggressive GAS infections.

Extensive Necrotic Skin Lesions Due to Post-varicella Protein S Deficiency

Postvaricella protein S deficiency is a rare and severe disease. We report a case of extensive necrotic skin lesions of acute onset 7 days after varicella in a 4-year-old girl. Protein S antigen and activity were <10%, and antiprotein S antibodies were detected. She was treated with anticoagulation, plasmapheresis and fresh frozen plasma. She survived but required leg amputation.

Rare presentation of rickettsial infection as purpura fulminans: a case report

BACKGROUND

Purpura fulminans is an acute life-threatening disorder characterized by intravascular thrombosis and hemorrhagic infarction of the skin complicated with disseminated intravascular coagulation. It is commonly seen in acute infections following meningococcal and streptococcal infections. Few cases of purpura fulminans following rickettsial infections have been described in the literature.

CASE PRESENTATION

We report a case of a 55-year-old Sri Lankan woman who presented to Teaching Hospital Peradeniya with a febrile illness, headache, and myalgia that progressed to an erythematous rash starting over the bilateral lover limbs and hands and that became black and necrotic with a few hemorrhagic blebs. She had normocytic anemia, platelet clumps, and monocytosis as well as a deranged clotting profile. The result of immunofluorescence antibody testing for rickettsial immunoglobulin G was strongly positive for Rickettsia conorii with a rise in titer convalescent sera, and a diagnosis of purpura fulminans following rickettsial infection was made. The patient made an excellent recovery with chloramphenicol treatment.

CONCLUSIONS

The treating physician should consider the rare but very treatable condition of rickettsial infection as a differential diagnosis in the etiological diagnostic workup of patients presenting with severe purpuric and hemorrhagic rash with fever.

Purpura Fulminans: Mechanism and Management of Dysregulated Hemostasis

Purpura fulminans (PF) is a highly thrombotic subtype of disseminated intravascular coagulation that can accompany severe bacterial, and more rarely, viral infections. PF is associated with an extremely high mortality rate, and patients often die of overwhelming multisystemic thrombosis rather than septic shock. Survivors typically experience amputation of involved extremities and significant scarring in affected areas. Despite the devastating clinical course associated with this hemostatic complication of infection, the mechanism of PF remains poorly understood. Severe acquired deficiency of protein C and dysfunction of the protein C-thrombomodulin pathway as well as other systems that exert a negative regulatory effect on coagulation have been implicated. Management of PF involves treatment of the underlying infection, aggressive anticoagulation, and robust transfusion support aimed at correcting acquired deficiencies in natural anticoagulant proteins. In this review, we address the diagnosis and management of PF with a focus on a rational approach to this condition informed by the available data. Proposed mechanisms underlying the dysregulation of coagulation seen in PF are also covered, and implications for therapy are discussed.

Anti-phospholipid syndrome: Current opinion on mechanisms involved, laboratory characterization and diagnostic aspects

Anti-phospholipid syndrome is a complex and severe clinical situation, associated with symptoms such as recurrent thrombosis, arterial or venous, at any site, pregnancy loss, and other related syndromes. These clinical burdens, are highly variable from patient to patient, and are associated with biological abnormalities, such as the presence of the Lupus Anticoagulant or phospholipid dependent antibodies, confirmed on two occasions at least 12 weeks apart. From the diagnosis standpoint, both, functional (clotting) or immunological assays, are difficult to standardize and to optimize, due to the absence of reference material, or a characteristic clinical group, and international reference preparations. Large cohort studies are necessary for defining the usefulness of each assay, in terms of specificity, sensitivity, accuracy and for following-up the disease evolution. Clotting assays are based on Activated Partial Thromboplastin Time (APTT) and diluted Russell Viper Venom Time (dRVVT), performed at low and high phospholipid concentration, or on 1:1 mixtures of tested sample and a normal plasma pool. They allow evaluation of the paradoxal effects of LAs, which are pro-thrombotic in vivo, and anticoagulant in vivo. Use of synthetic phospholipids improves assay specificities and sensitivities, especially in patients treated with anticoagulants. Immunoassays can also be used for testing phospholipid dependent antibodies, first identified and measured as anti-cardiolipin antibodies, but now characterized as targeted to phospholipid cofactor proteins: mainly β2GP1 (which exposes cryptic epitopes upon binding to phospholipids), and in some cases prothrombin, and more rarely Protein S, Factor XIII, Protein Z or Annexin V. Use of optimized assays designed with well-characterized anionic phospholipids, then complexed with highly purified phospholipid cofactor protein (mainly β2GP1), offers a better link between reactivity and clinical associations, than the former assays which were empirically designed with cardiolipin. Standardization also remains complicated due to the absence of international standards and harmonized quantitation units. Validation on large cohorts of negative and positive patients remains the key approach for defining assay performance and clinical usefulness. Laboratory practice for all these methods is now greatly facilitated thanks to the use of automated instruments and dedicated software. Along with clinical criteria, laboratory assays are of great usefulness for identification and confirmation of the anti-phospholipid syndrome and they allow disease follow-up when appropriate patient management is in place.

Purpura fulminans secondary to rickettsial infections: A case series

Purpura fulminans (PF) is a descriptive term used to describe a heterogeneous group of disorders characterized by rapidly progressive purpuric lesions that may develop into extensive areas of skin necrosis, and peripheral gangrene. This rare disorder is associated with laboratory evidence of consumptive coagulopathy and is often fatal. PF is usually associated with many infections, most notably with meningococcal, staphylococcal, and streptococcal infections. However, there are very few reports of this entity with spotted fever and scrub typhus from India. Rickettsial infections are an underdiagnosed group of diseases presenting as acute febrile illness, with high mortality in untreated cases. Of the available tests, Weil–Felix is a handy and economical tool for early diagnosis of this fatal disease especially in resource poor settings. We present four infants with PF secondary to rickettsial fever diagnosed by the Weil–Felix test.

Purpura fulminans associated with acute West Nile virus encephalitis

Purpura fulminans is a progressive thrombotic disorder that presents with widespread purpura due to deficiency or dysfunction of protein C or protein S. Lesions present as well-demarcated erythematous macules that progress to irregular areas of hemorrhagic necrosis.West Nile virus is a member of the Flaviviridae family transmitted to humans through the bite of various mosquito species. It manifests as West Nile fever in 25% of those infected and less commonly as neuroinvasive disease. An African American man in his fortiespresented with altered mental status and was noted to have evidence of disseminated intravascular coagulation according to his lab data. He then developed dusky skin discoloration and systemic flaccid bullae with desquamation. Biopsy was consistent with purpura fulminans and the patient eventually developed symmetric peripheral gangrene, requiring amputations of all four extremities. Infectious work up revealed positive testing for IgM and IgG antibodies in serum and cerebrospinal fluid leading to the diagnosis of acute West Nile Virus encephalitis. We present this case to describe the rarely reported association of purpura fulminans with West Nile Virus infection.

Vascular Complications of Varicella: Description of 4 Cases and a Review of Literature

Stroke and deep venous thrombosis are rare complications of varicella zoster infection. We report 3 cases of children with a stroke and 1 case of a boy with a deep venous thrombosis after recent chicken pox.

[Deep venous thrombosis complications during infections in pediatric patients: analysis of a series of 24 cases]

Venous thromboembolism disease (VTE) is rare in children (5.3 of 10,000 hospitalized children). However, morbidity and mortality are high, especially when the child is already suffering from severe sepsis. We report an analytical study of 24 cases of deep venous thrombosis occurring in children during infection, recorded at the Montpellier University Hospital between 1999 and 2009. Many parameters were studied in each population (age, sex, familial and personal history of thrombosis, history of thrombophilia, the presence of a venous catheter, a causative organism, time to onset of thrombus, topography of lesions, acquired abnormalities of hemostasis, and thrombosis prophylaxis). The children were aged from 1 day of life to 16 years. Thromboses occurred in two clinical contexts: "contact" thrombosis (which appeared near the infection) and disseminated thrombosis. This is an early complication because in most of the cases, it appeared in the first 10 days of sepsis. Infection and coagulation appear to be closely related and the states of latent or decompensated disseminated intravascular coagulation are common. Nevertheless, it is not possible to predict the occurence of a thrombotic event. The presence of risk factors (venous catheters, acquired thrombophilia, or constitutional thrombophilia) may increase the thrombogenic potential of the infection. VTE should always be suspected and sought in case of an unfavorable clinical course, and routine prophylaxis of thrombosis during sepsis should be discussed.

Update on varicella zoster virus vasculopathy

Primary infection of humans with varicella zoster virus (VZV) causes varicella (chickenpox), after which the virus becomes latent in cranial nerve ganglia, dorsal root ganglia and autonomic ganglia along the entire neuraxis. As VZV-specific cell-mediated immunity declines in elderly and immunocompromised individuals, VZV reactivates from one or more ganglia and typically causes herpes zoster (shingles). Zoster may also be complicated by VZV vasculopathy due to productive virus infection of the cerebral arteries. In recent decades, the clinical spectrum of VZV vasculopathy has expanded to include not only transient ischemic attacks and ischemic and hemorrhagic stroke, but also multifocal VZV vasculopathy, with temporal artery infection mimicking giant cell arteritis, extracranial vasculopathy, aneurysm with and without subarachnoid hemorrhage, arterial dissection and dolichoectasia, ischemic cranial neuropathies, cerebral venous sinus thrombosis, spinal cord infarction and peripheral thrombotic disease.

Pediatric thrombophilia

Pediatric thrombosis and thrombophilia are increasingly recognized and studied. In this article, both the inherited and acquired factors for the development of thrombosis in neonates and children are categorized using the elements of Virchow's triad: stasis, hypercoagulable state, and vascular injury. The indications and rationale for performing thrombophilia testing are described. Also included are discussions on who, how, when, and why to test. Finally, recommendations for the use of contraceptives for adolescent females with a family history of thrombosis are outlined.

Anti-human protein S antibody induces tissue factor expression through a direct interaction with platelet phosphofructokinase

INTRODUCTION

Autoantibodies including anti-human protein S antibody (anti-hPS Ab) and anti-human protein C antibody (anti-hPC Ab) can be detected in patients with autoimmune diseases with hypercoagulability. The objective of the present study was to determine the effects and molecular pathways of these autoantibodies on tissue factor (TF) expression in human coronary artery endothelial cells (HCAECs).

MATERIALS AND METHODS

HCAECs were treated with anti-hPS Ab or anti-hPC Ab for 3 hours. TF expression was measured by real-time PCR and Western blot. TF-mediated procoagulant activity was determined by a commercial kit. MAPK phosphorylation was analyzed by Bio-Plex luminex immunoassay and Western blot. The potential proteins interacting with anti-hPS Ab were studied by immunoprecipitation, mass spectrometry and in vitro pull-down assay.

RESULTS

Anti-hPS Ab, but not anti-hPC Ab, specifically induced TF expression and TF-mediated procoagulant activity in HCAECs in a concentration-dependent manner. This effect was confirmed in human umbilical endothelial cells (HUVECs). ERK1/2 phosphorylation was induced by anti-hPS Ab treatment, while inhibition of ERK1/2 by U0216 partially blocked anti-hPS Ab-induced TF upregulation (P<0.05). In addition, anti-hPS Ab specifically cross-interacted with platelet phosphofructokinase (PFKP) in HCAECs. Anti-hPS Ab was able to directly inhibit PFKP activities in HCAECs. Furthermore, silencing of PFKP by PFKP shRNA resulted in TF upregulation in HCAECs, while activation of PFKP by fructose-6-phosphate partially blocked the effect of anti-hPS Ab on TF upregulation (P<0.05).

CONCLUSIONS

Anti-hPS Ab induces TF expression through a direct interaction with PFKP and ERK1/2 activation in HCAECs. Anti-hPS Ab may directly contribute to vascular thrombosis in the patient with autoimmune disorders.

[Purpura fulminans, venous thrombosis and constitutional thrombophilia in an infant]

The association of idiopathic purpura fulminans (PF) and venous thrombosis (VT) seldom reveals constitutional thrombophilia in an infant. We report a case of PF in an 18-month-old infant. Laboratory tests showed disseminated intravascular coagulation (DIVC) with normal rates of C and S proteins and antithrombin. The echo-Doppler examination conveyed venous thrombosis of the lower limbs, while the genetic study showed heterozygous mutation of Factor II (G 20210A). Precocious and multidisciplinary management included frozen fresh plasma supplementation and necrosectomy with skin grafts. The diagnosis and therapeutic problems posed by PF combined with deep venous thrombosis are discussed.

Thrombophilia and varicella zoster in children

From 2005 to 2011, 25 children of both sexes (13 boys and 12 girls, mean age 7.8 ± 2.5 years, 5-12.4 years) with acute varicella zoster virus (VZV) infection were selected. Five patients showed venous thromboembolism characterized by deep venous thrombosis (DVT). Comparison of activated partial thromboplastin time, antithrombin III, D-dimer, lupus anticoagulant, free S protein (PS), C protein, and antiphospholipid and PS antibodies was performed on children with acute VZV and DVT (group I), acute uncomplicated VZV (group II), and 30 healthy controls of both sexes (15 boys and 15 girls, mean age 7.5 ± 2.6 years, group III). Genetic thrombophilic mutations (Factor V Leiden, MTHFR C677T, and Prothrombin G20210A) were evaluated. Coagulation disorders and PS antibody were found in children with acute VZV (groups I and II). Significant differences were shown among the three groups (P < 0.05). Acute VZV infection could be associated with coagulation disorders and production of inhibitory PS antibodies in many uncomplicated cases.

Prothrombotic profile in children with peripheral gangrene: a single center experience

Peripheral gangrene is rare in children. Protein C, protein S, and antithrombin deficiency, positivity for anticardiolipin antibodies or lupus anticoagulant and factor V Leiden mutation are important causes of thrombosis in the venous system. There is paucity of literature on the contribution of these factors in children with peripheral gangrene. We evaluated the role of aforementioned factors in children with peripheral gangrene. Protein S deficiency was seen in one case and another was transiently positive for lupus anticoagulant. None of the 11 age- and sex-matched normal controls had protein C, protein S, or antithrombin deficiency. Our results indicate that deficiency of protein C, protein S, and antithrombin, and positivity for anticardiolipin antibodies, lupus anticoagulant, and factor V Leiden are uncommon causes of peripheral gangrene in children in north-western India. Fibrinolytic and antiplatelet parameters were not tested. Testing for these may yield further clues to the etiology of this condition.

Varicella-related musculoskeletal complications in children

Eight children with post-varicella musculoskeletal complications were treated between 2001 and 2009. The complications that were observed were cellulitis (three children), pyomyositis (three children), osteomyelitis (two children) and gangrene (one child). On average, 8.8 days elapsed between primary varicella infection and complication. The most common presentation was pain. Before we started treating them, all children received antibiotics during interhospital transfers (average: 2.4). Interventions included drainage (eight), fasciatomy (one), arthrotomy (one), bone drilling (one), and amputation (one). Blood cultures were negative in all children. Two children had positive pus cultures for Staphylococcus aureus, one of them had a methicillin-resistant S. aureus infection. One of the four children who developed coagulopathy ended with significant morbidity. Varicella-related methicillin-resistant S. aureus osteomyelitis suggests a widening spectrum of these infections.

Empiric treatment of protracted idiopathic purpura fulminans in an infant: a case report and review of the literature

Introduction

Idiopathic purpura fulminans is a cutaneous thrombotic disorder usually caused by autoimmune-mediated protein C or S deficiency. This disorder typically presents with purpura and petechiae that eventually slowly or rapidly coalesce into extensive, necrotic eschars on the extremities. We present the first known case of idiopathic purpura fulminans consistent with prior clinical presentations in the setting of a prothrombotic genetic mutation, but without hallmark biochemical evidence of protein C or protein S deficiency. Another novel feature of our patient's presentation is that discontinuation of anti-coagulation has invariably led to recurrence and formation of new lesions, which is unexpected in idiopathic purpura fulminans because clearance of autoimmune factors should be followed by restoration of anti-coagulant function. Although this disease is rare, infants with suspected idiopathic purpura fulminans should be rapidly diagnosed and immediately anti-coagulated to prevent adverse catastrophic outcomes such as amputation and significant developmental delay.

Case presentation

A six-month-old Caucasian boy was brought to our pediatric hospital service with a low-grade fever and subacute, symmetric, serpiginous, stellate, necrotic eschars on his forearms, legs and feet that eventually spread non-contiguously to his toes, thighs and buttocks. In contrast to his impressive clinical presentation, his serologic evaluation was normal, and he was not responsive to corticosteroids and antibiotics. Full-thickness skin biopsies revealed dermal vessel thrombosis, leading to a diagnosis of idiopathic purpura fulminans and successful treatment with low-molecular-weight heparin, which was transitioned to warfarin. Long-term management has included chronic anti-coagulation because of recurrence of lesions with discontinuation of treatment.

Conclusion

In infants with necrotic eschars, it is important to first consider infectious, inflammatory and hematologic etiologies. In the absence of etiology for protracted idiopathic purpura fulminans, management should include tissue biopsy, in which thrombotic findings warrant a trial of empiric anti-coagulation. Some infants, including our patient, may need long-term anti-coagulation, especially when the underlying etiology of coagulation remains unidentified and symptoms recur when treatment is halted. Given that our patient still requires anti-coagulation, he may have a yet to be identified autoimmune-mediated mechanism for his truly idiopathic case of protracted purpura fulminans.

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

Acquired protein S deficiency is a rare complication of varicella zoster infection often resulting in purpura fulminans, which is a potentially life-threatening syndrome of intravascular thrombosis and haemorrhagic infarction of the skin. Patients are presumed to develop crossreacting autoantibodies to the virus and protein S. There is no consensus on how best to manage these patients but previous recommendations focus on plasmapheresis and plasma exchange. We report the case of a 3-year-old girl with post varicella purpura fulminans owing to protein S deficiency, who was diagnosed promptly and made a full recovery following immediate treatment with anticoagulation and plasma support. This suggests that if anticoagulation is used, plasma exchange is not always necessary. As recovery occurred without plasmapheresis, we were able to track protein S levels. The timing of protein S recovery was consistent with the waning titre of an acquired immunoglobulin G autoantibody.

Chickenpox is not always benign: postvaricella purpura fulminans requires prompt and aggressive treatment

We present 2 patients, who were admitted owing to rapidly progressing purpuric lesions due to postvaricella purpura fulminans, a coagulopathy leading to life- or limb-threatening thrombosis caused by a severe transient autoimmune protein S deficiency. Laboratory results were being consistent with disseminated intravascular coagulation secondary to protein S deficiency; treatment with fresh frozen plasma, intravenous immunoglobulins, and prednisone was started. In our experience, a prompt therapy may limit the course and the extent of the disease. We present a review of the topic with supporting literature for the therapeutic options. Therefore, we should be reminded that purpura fulminans is a rare but severe complication of chickenpox, which demands quick action.

Postinfectious purpura fulminans secondary to varicella-induced protein S deficiency

Varicella is usually a benign and self-limited disease of infancy and childhood although it has been recognized that it sometimes has severe and life-threatening complications. We report a case of postinfectious purpura fulminans with acquired protein S deficiency following varicella in a 6-year-old child and discuss the underlying mechanism of postinfectious purpura fulminans.

Varicella-associated purpura fulminans and multiple deep vein thromboses: a case report

Varicella-associated purpura fulminans is a rare syndrome associated with substantial morbidity and mortality. General supportive care, heparinization, and plasma infusions are the mainstays of treatment. A patient aged 8 years and 8 months with purpura fulminans and multiple deep vein thromboses after varicella infection because of deficiencies of proteins C and S is presented in this case report.

Nonbacterial purpura fulminans and severe autoimmune acquired protein S deficiency associated with human herpesvirus-6 active replication

Nonbacterial purpura fulminans (PF) is rare, usually follows viral infection in young children, and is characterized by specific coagulation disorders, requiring specific therapy. Following a transient rash, a 2-year-old previously healthy girl developed PF without haemodynamic impairment. Laboratory data revealed disseminated intravascular coagulation and a severe transient protein S deficiency. Antiprotein S autoantibodies and active human herpesvirus-6 (HHV6) replication were demonstrated. Purpuric skin lesions spread very rapidly despite broad-spectrum antibiotics and right leg amputation. Plasmapheresis and intravenous immunoglobulins gave complete clinical recovery and normalization of protein S level within 10 days, with progressive clearance of antiprotein S autoantibodies. Transient severe protein S deficiencies have previously been reported in patients with nonbacterial PF, usually after varicella infection. This is the first documented case of PF after HHV6 infection.

[Post-varicella purpura fulminans: potentially fatal]

Although varicella is usually a benign disease, some of its complications, such as post-varicella purpura fulminans, can be fatal. Its pathophysiological mechanism is caused by the production of antibodies to protein C and protein S in the coagulation cascade. This could have fatal consequences for those patients with partial deficiency of these proteins that develop disseminated intravascular coagulation. Treatment is symptomatic: fresh frozen plasma to treat protein depletion, antithrombin III and heparinization against thrombus formation, and anti-inflammatory drugs (steroids). However, new therapies, such as prostaglandin E1 IV and prostacyclin, are being introduced.

Spectrum of purpura fulminans

Purpura Fulminans is a severe disorder of acute onset with high morbidity and mortality. It is characterized by DIC with thrombocytopenia, hyofibrinogenemia, hypothrombinemia and anemia. It most often occurs in young with sudden appearance of symmetrical, tender, ecchymotic skin lesions usually involving the lower extremities. An infectious and noninfectious etiology has been proposed. Early recognition and early therapy with appropriate antibiotics and heparin is known to limit both morbidity and mortality. This article reports 5 cases of Purpura Fulminans treated at our centre with review of etiology, pathogenesis, clinical features and treatment.

Acute renal cortical necrosis due to acquired antiprotein S antibodies

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.

Post varicella hepatic actinomycosis in a 5-year-old girl mimicking acute abdomen

Actinomycosis is an indolent, slowly progressive infection caused by gram-positive, anaerobic or microaerophilic bacteria. Hepatic involvement is rare and generally secondary to abdominal or thoracic actinomycosis. Hepatic actinomycosis in children may mimic a wide variety of diseases and thus make the diagnosis much more challenging. Here, we report a 5-year-old girl with apparently primary hepatic actinomycosis mimicking acute abdomen 2 weeks after varicella. The diagnosis was made by ultrasonic guided fine needle aspiration biopsy of a hypoechoic lesion of 3.5 cm diameter in the liver showing sulfur granules surrounded by neutrophils. Hepatic actinomycosis should be taken into account when evaluating acute abdomen symptoms in children.

Presentation and outcome of purpura fulminans associated with peripheral gangrene in 12 patients at Mayo Clinic

BACKGROUND

Dermatologists may be called to assist in the diagnosis and management of purpura fulminans.

METHODS

This retrospective case series details the clinical presentation and outcomes of patients presenting with purpura fulminans associated with peripheral gangrene between 1989 and 2004.

RESULTS

All 12 patients presented with sudden onset of purpuric patches and evolving gangrene of the extremities in association with a shock syndrome (hypotension, oliguria). Eleven patients had disseminated intravascular coagulation. The cause of purpura fulminans was infectious in 9 patients, surgical in two, and cancer in one. Three patients died (25%) within a week of onset of purpura fulminans. Of the 9 surviving patients, 8 required amputation of at least one limb. Four patients required amputation of all 4 limbs.

LIMITATIONS

Retrospective study design, varying clinical descriptions, and potential referral bias are limitations.

CONCLUSION

Purpura fulminans in association with symmetric peripheral gangrene is an ominous clinical presentation.