Splenic infarction due to transient antiphospholipid antibodies induced by acute Epstein-Barr virus infection

Herpesvirus Infection of Endothelial Cells as a Systemic Pathological Axis in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Understanding the pathophysiology of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is critical for advancing treatment options. This review explores the novel hypothesis that a herpesvirus infection of endothelial cells (ECs) may underlie ME/CFS symptomatology. We review evidence linking herpesviruses to persistent EC infection and the implications for endothelial dysfunction, encompassing blood flow regulation, coagulation, and cognitive impairment-symptoms consistent with ME/CFS and Long COVID. This paper provides a synthesis of current research on herpesvirus latency and reactivation, detailing the impact on ECs and subsequent systemic complications, including latent modulation and long-term maladaptation. We suggest that the chronicity of ME/CFS symptoms and the multisystemic nature of the disease may be partly attributable to herpesvirus-induced endothelial maladaptation. Our conclusions underscore the necessity for further investigation into the prevalence and load of herpesvirus infection within the ECs of ME/CFS patients. This review offers conceptual advances by proposing an endothelial infection model as a systemic mechanism contributing to ME/CFS, steering future research toward potentially unexplored avenues in understanding and treating this complex syndrome.

Splenic Infarction Due to Epstein-Barr Virus: A Case Report and Literature Review

Splenic infarction is a rare and likely underdiagnosed complication of Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM). Here, we describe an 18-year-old Guyanese male with persistent severe left-sided abdominal pain found to be EBV positive and have a large splenic infarct, along with a transient decrease in protein C, protein S, and antithrombin III activity levels. He was treated with supportive care and anticoagulated with heparin and apixaban. We review prior reports and perspectives on underlying pathophysiology, diagnosis, and the management of these cases, which likely do not require anticoagulation but may be considered on a per-case basis.

Infectious Mononucleosis-Induced Splenic Infarction: Perhaps More Common in Healthy Individuals Than Previously Thought

Infectious mononucleosis (IM) is a clinical syndrome that presents as a triad of fever, pharyngitis, and lymphadenopathy. In most cases, it is caused by the Epstein-Barr virus (EBV), which spreads through upper respiratory secretions, particularly saliva, earning its name as the Kissing Disease. In most cases, IM is self-limiting and resolves in two to four weeks without significant sequelae following supportive care. Although rare, IM has been associated with several serious and sometimes life-threatening complications, involving almost any organ system. Splenic infarction is one rare complication of IM due to EBV infection. In the past, IM-induced splenic infarction in the setting of EBV was believed to be rare and mostly limited to patients with underlying hematologic comorbidities. However, we propose this condition to be more common and more likely to occur in individuals without significant medical history than previously suspected. We report a relatively healthy young male patient in his thirties, with no previous history of coagulopathy or complex medical conditions, who was found to have IM-induced splenic infarction.

Splenic Infarction: A Rare Complication of Infectious Mononucleosis

Infectious mononucleosis (IM) is caused by Epstein-Barr virus (EBV), and the condition is characterized by sore throat, fever, lymphadenopathy, and atypical lymphocytosis. These infections are common in early childhood, with a second peak occurring in late adolescence. EBV is spread by contact with oral secretions. Most cases of IM are self-limited. However, there are associated complications, some of which can be serious and fatal. We report the case of a 20-year-old man with splenic infarction and exuberant peritonsillar abscess secondary to an EBV infection. This case highlights the importance of accurate diagnoses and frequent monitoring in IM patients, given the risk of airway obstruction.

Anticoagulation in COVID-19: a review of current literature and guidelines

Severe acute respiratory syndrome coronavirus 2 infections are associated with greater risk of both arterial and venous thromboembolic events.Pathophysiology and Clinical implications: This has been attributed to a florid proinflammatory state resulting in microvascular dysfunction, activation of platelets and procoagulant systems as well as possible direct endothelial injury. The associated morbidity and mortality of these events has prompted much speculation and varied anticoagulation and fibrinolytic strategies based on multiple criteria including disease severity and biomarkers. No clear definitive benefit has been established with these approaches, which have frequently led to greater bleeding complications without significant mortality benefit.Overview: In this review, we outline the burden of these thromboembolic events in coronavirus disease-2019 (COVID-19) as well as the hypothesized contributory biological mechanisms. Finally, we provide a brief overview of the major clinical studies on the topic, and end with a summary of major societal guideline recommendations on anticoagulation in COVID-19.

Epstein-Barr virus (EBV) induced pneumonitis in an immunocompetent adult: A case report

Epstein Barr Virus (EBV) is one of the herpes viruses that is responsible for causing infectious mononucleosis, lymphomas, and carcinomas primarily in immunocompromised individuals. We present a case of EBV-induced pneumonitis in an immunocompetent female, successfully treated with steroids. The patient is a 70 year-old female with a history of infectious mononucleosis in her teens who presented to the emergency room with worsening shortness of breath, associated with cough and fever. She underwent extensive work up and her serologic workup revealed positive anti-EBV antibodies, pointing towards the diagnosis of EBV induced pneumonitis. EBV-induced Pneumonitis is a very rare entity and is especially hardly seen among immunocompetent individuals. This interesting case shows that in this new era of viral pneumonias, EBV induced pneumonitis should be considered among differentials when dealing with lung infections. Prompt initiation of treatment with steroids or antiviral medication may result in complete recovery. The choices among treatment options can be individualized according to the severity of disease, course of disease progression, and side effect profile of medications. In our case we were able to successfully treat the patient with high dose steroids only.

Splenic infarction and infectious diseases in Korea

Background

The spleen contains immune cells and exhibits a pattern of infarction different from other organs; as such, splenic infarction (SI) may provide important clues to infection. However, the nature of the relationship between SI and infectious disease(s) is not well understood. Accordingly, this retrospective study investigated the relationship between SI and infection.

Methods

Hospital records of patients with SI, who visited Inha University Hospital (Incheon, Republic of Korea) between January 2008 and December 2018, were reviewed. Patient data regarding clinical presentation, causative pathogens, risk factors, and radiological findings were collected and analyzed.

Results

Of 353 patients with SI, 101 with infectious conditions were enrolled in this study, and their data were analyzed to identify associations between SI and infection. Ten patients were diagnosed with infective endocarditis (IE), and 26 exhibited bacteremia without IE. Twenty-seven patients experienced systemic infection due to miscellaneous causes (negative result on conventional automated blood culture), including the following intracellular organisms: parasites (malaria [n = 12], babesiosis [n = 1]); bacteria (scrub typhus [n = 5]); viruses (Epstein–Barr [n = 1], cytomegalovirus [n = 1]); and unidentified pathogen[s] (n = 7). Splenomegaly was more common among patients with miscellaneous systemic infection; infarction involving other organs was rare. Thirty-eight patients had localized infections (e.g., respiratory, intra-abdominal, or skin and soft tissue infection), and most (35 of 38) had other risk factors for SI.

Conclusions

In this study, various infectious conditions were found to be associated with SI, and intracellular organisms were the most common causative pathogens. Further studies are needed to examine other possible etiologies and the underlying pathophysiological mechanisms.

Epstein Barr Virus-induced Antiphospholipid Antibodies Resulting in Splenic Infarct: A Case Report

Splenic infarction is a rare cause of abdominal pain. We herein reported a unique case of a 30-year-old male patient who developed a splenic infarct during the acute phase of Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM) and was subsequently found to have the presence of antiphospholipid antibodies (APA).

Splenic Infarction in Acute Cytomegalovirus and Human Parvovirus Concomitant Infection

We present a case report of a 35-year-old woman who had splenic infarction. She had persistent high fever, systemic joint pain, and abnormal liver function. She was diagnosed with cytomegalovirus and human parvovirus B19 concomitant infection. Her coagulopathy test revealed no abnormal results. She was treated with intravenous ganciclovir for 13 days; consequently, her splenic infarction improved after 7 weeks. As per our knowledge, this is the first case of cytomegalovirus and parvovirus B19 coinfection complicated by splenic infarction. Cytomegalovirus and parvovirus B19 may induce a hypercoagulation state during the acute phase.

Splenic Infarction as a Delayed Febrile Complication Following Radical Gastrectomy for Gastric Cancer Patients: Computed Tomography-Based Analysis

BACKGROUND

The aim of this study was to evaluate the incidence and clinical characteristics of splenic infarction (SI) in gastric cancer patients who have undergone gastrectomy.

METHODS

For this study, the medical records of 1084 patients were reviewed and 877 patients were ultimately enrolled. The times of symptom onset, diagnosis of SI, and complete resolution on CT were calculated from the day of the operation. Based on the wedge shape of the SI in all cases, the total volume of the SI was measured based on that of a corn kernel.

RESULTS

Thirty-six patients (4.10%) were diagnosed with SI after gastrectomy; four of these patients (0.45%) developed complications associated with the SI. Total gastrectomy and extended lymph node dissection were risk factors for development of SI. Patients with complications exhibited inflammatory signs between 7 and 10 days after surgery. The mean volume of the SI was 4025.69 mm³. The mean time to complete resolution on the CT scan was 327 days postoperatively. In 30 cases, small branched arteries from the splenic artery that could have caused the SI were retrospectively detected on the preoperative CT scans.

CONCLUSION

Although the incidence of the SI was low, large volume of the SI is associated with complication development. Measuring the infarction volume via a CT scan may be useful to decide on the treatment strategy. Preoperative 3-D reconstruction of the splenic artery tributaries may help reduce the risk of inadvertent SI.

Splenic Infarction: An Under-recognized Complication of Infectious Mononucleosis?

Splenic infarction is a rare complication of infectious mononucleosis. We describe 3 cases of splenic infarction attributed to infectious mononucleosis that we encountered within a 2-month period. We underscore the awareness of this potential complication of infectious mononucleosis and discuss the differential diagnosis of splenic infarction, including infectious etiologies. While symptomatic management is usually sufficient for infectious mononucleosis-associated splenic infarction, close monitoring for other complications, including splenic rupture, is mandated.

Splenic infarct in a patient with Infectious Mononucleosis: a rare presentation

We report a case of a 25-year-old obese, currently smoking, female diagnosed with EBV infectious mononucleosis. The patient complained of sudden onset abdominal pain with progressively increasing intensity in the left upper quadrant. Abdominal CT scan showed a wedge infarct of the spleen. We present this rare case that EBV may cause splenic infarct in young adults.

Sarcoidosis with fever and a splenic infarct due to CMV or lymphoma?

We present a case of an adult female with a past history of pulmonary sarcoidosis who presented with fever, night sweats, profound fatigue, and LUQ abdominal pain. Sarcoidosis is an afebrile disorder (excluding Lofgren's syndrome, Heerfordt's syndrome or neurosarcoidosis). Therefore, the presence of fever with sarcoidosis should suggest infection, usually viral, or lymphoma. Sarcoidosis-lymphoma syndrome describes the evolution of a lymphoma in long standing sarcoidosis. Fever aside, possible lymphoma is suggested by otherwise unexplained fever, pleural unilateral effusion, highly elevated ESR or ferritin levels. In this case, a viral etiology was suggested because of atypical lymphocytosis and mildly elevated transaminases. In this patient, CMV IgM titers and elevated CMV PCR viral load confirmed the diagnosis of CMV infectious mononucleosis with lung and liver involvement. In this case CMV infectious mononucleosis was accompanied by procoagulant activity which resulted a DVT, pulmonary emboli and splenic infarct. We believe this to be the first reported case of CMV infectious mononucleosis splenic infarct in a patient with a history of sarcoidosis.

Thrombosis and antiphospholipid antibody syndrome during acute Q fever: A cross-sectional study

Q fever is a neglected and potentially fatal disease. During acute Q fever, antiphospholipid antibodies are very prevalent and have been associated with fever, thrombocytopenia, acquired heart valve disease, and progression to chronic endocarditis. However, thrombosis, the main clinical criterion of the 2006 updated classification of the antiphospholipid syndrome, has not been assessed in this context. To test whether thrombosis is associated with antiphospholipid antibodies and whether the criteria for antiphospholipid syndrome can be met in patients with acute Q fever, we conducted a cross-sectional study at the French National Referral Center for Q fever.Patients included were diagnosed with acute Q fever in our Center between January 2007 and December 2015. Each patient's history and clinical characteristics were recorded with a standardized questionnaire. Predictive factors associated with thrombosis were assessed using a rare events logistic regression model. IgG anticardiolipin antibodies (IgG aCL) assessed by an enzyme-linked immunosorbent assay were tested on the Q fever diagnostic serum. A dose-dependent relationship between IgG aCL levels and thrombosis was tested using a receiver operating characteristic (ROC) analysis.Of the 664 patients identified for inclusion in the study, 313 (47.1%) had positive IgG aCL and 13 (1.9%) were diagnosed with thrombosis. Three patients fulfilled the antiphospholipid syndrome criteria. After multiple adjustments, only positive IgG aCL (relative risk, 14.46 [1.85-113.14], P = .011) were independently associated with thrombosis. ROC analysis identified a dose-dependent relationship between IgG aCL levels and occurrence of thrombosis (area under curve, 0.83, 95%CI [0.73-0.93], P < .001).During acute Q fever, antiphospholipid antibodies are associated with thrombosis, thrombocytopenia, and acquired valvular heart disease. Antiphospholipid antibodies should be systematically assessed in acute Q fever patients. Hydroxychloroquine, which has been previously shown to antagonize IgG aCL pathogenic properties, should be tested in acute Q fever patients with anticardiolipin antibodies to prevent antiphospholipid-associated complications.Key Point: In addition to fever, thrombocytopenia and acquired valvular heart disease, antiphospholipid antibodies are associated with thrombosis during acute Q fever.

Systematic review of case reports of antiphospholipid syndrome following infection

OBJECTIVE

The objective of this study was to conduct a systematic review of case reports documenting the development of antiphospholipid syndrome or antiphospholipid syndrome-related features after an infection.

METHODS

We searched Medline, EMBASE, Web of Science, PubMed ePubs, and The Cochrane Library - CENTRAL through March 2015 without restrictions. Studies reporting cases of antiphospholipid syndrome or antiphospholipid syndrome-related features following an infection were included.

RESULTS

Two hundred and fifty-nine publications met inclusion criteria, reporting on 293 cases. Three different groups of patients were identified; group 1 included patients who fulfilled the criteria for definitive antiphospholipid syndrome (24.6%), group 2 included patients who developed transient antiphospholipid antibodies with thromboembolic phenomena (43.7%), and group 3 included patients who developed transient antiphospholipid antibodies without thromboembolic events (31.7%). The most common preceding infection was viral (55.6%). In cases that developed thromboembolic events Human immunodeficiency and Hepatitis C viruses were the most frequently reported. Parvovirus B19 was the most common in cases that developed antibodies without thromboembolic events. Hematological manifestations and peripheral thrombosis were the most common clinical manifestations. Positive anticardiolipin antibodies were the most frequent antibodies reported, primarily coexisting IgG and IgM isotypes. Few patients in groups 1 and 2 had persistent antiphospholipid antibodies for more than 6 months. Outcome was variable with some cases reporting persistent antiphospholipid syndrome features and others achieving complete resolution of clinical events.

CONCLUSIONS

Development of antiphospholipid antibodies with all traditional manifestations of antiphospholipid syndrome were observed after variety of infections, most frequently after chronic viral infections with Human immunodeficiency and Hepatitis C. The causal relationship between infection and antiphospholipid syndrome cannot be established, but the possible contribution of various infections in the pathogenesis of antiphospholipid syndrome need further longitudinal and controlled studies to establish the incidence, and better quantify the risk and the outcomes of antiphospholipid-related events after infection.

Fulminant ecchymosis as the initial manifestation of antiphospholipid syndrome (APS) triggered by respiratory syncytial virus (RSV) infection: A case report and review of the literature

We present a unique and informative instance of respiratory syncytial virus (RSV) infection associated with antiphospholipid syndrome (APS), and discuss this case in the context of the literature addressing the immunopathogenesis of APS associated with diverse infections. We describe the case of a 43-year-old man with no significant past medical history who presented with the acute onset of fever, hemoptysis, and extensive bullous, ecchymotic lesions in both lower extremities. Punch biopsy of the lesion demonstrated thrombotic vasculopathy. Further evaluation revealed serum antiphospholipid antibodies as well as a positive RSV PCR in a nasal swab specimen. Clinical manifestations, positive laboratory and pathological findings were strongly suggestive of APS associated with a recent RSV infection. When an infectious etiology is considered for APS, RSV should also be included in the differential diagnosis.

The environment and antiphospholipid syndrome

The etiology of autoimmune diseases is multifactorial. The degree to which genetic and environmental factors influence susceptibility to autoimmune diseases is poorly defined. It is believed that versatile clinical presentations of autoimmune diseases stem from various combinations of the genetic and environmental factors. One of the newly diagnosed autoimmune diseases is the antiphospholipid syndrome (APS). APS is characterized by vascular thrombosis, and/or pregnancy morbidity associated with anticardiolipin (aCL), anti-β2-glycoprotein-I (anti-β2GPI) and lupus anticoagulant (LAC).

Splenic infarction associated with acute infectious mononucleosis due to Epstein-Barr virus infection

The purpose of this study was to report a case of a previously healthy 20-year-old woman diagnosed with splenic infarction following infectious mononucleosis (IM) by Epstein-Barr virus (EBV) infection and to perform the first systematic review of the clinical characteristics of splenic infarction associated with IM. A systematic review was conducted using English, French, and Japanese literatures of splenic infarction associated with IM due to EBV infection published between 1961 and 2015 in PubMed Medline. A total of 19 cases were extracted from the collected articles. Left upper quadrant (LUQ) pain was observed in 15 (79%) patients. Splenectomy was performed in five (26%) cases, among which four patients presented with stable vital signs. Splenic rupture was accompanied in two (10%) patients. The median time from the onset of IM symptoms to the diagnosis of splenic infarction was 5 days (range, 1-25 days). Fourteen (74%) of 19 patients experienced improvement through medical treatment, and there were no deaths. Splenic infarction associated with IM due to EBV infection can show a favorable clinical outcome after medical treatment. Clinicians should consider the possibility of splenic infarction when patients with IM experience LUQ pain. J. Med. Virol. 89:332-336, 2017. © 2016 Wiley Periodicals, Inc.

Splenic Infarction in Acute Infectious Mononucleosis

BACKGROUND

The evaluation of a febrile patient with acute abdominal pain represents a frequent yet possibly challenging situation in the emergency department (ED). Splenic infarction is an uncommon complication of infectious mononucleosis, and may have a wide range of clinical presentations, from dramatic to more subtle. Its pathogenesis is still incompletely understood, yet it may be associated with the occurrence of transient prothrombotic factors.

CASE REPORT

We report the case of a 14-year-old boy who presented with fever, sore throat, left upper quadrant abdominal pain, and splenomegaly, with no history of recent trauma. Laboratory tests revealed a markedly prolonged activated partial thromboplastin time and positive lupus anticoagulant. Abdominal ultrasonography showed several hypoechoic areas in the spleen consistent with multiple infarctions. Magnetic resonance imaging eventually confirmed the diagnosis. He was admitted for observation and supportive treatment, and was discharged in good condition after 7 days. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Spontaneous splenic infarction should be considered in the differential list of patients presenting with left upper quadrant abdominal pain and features of infectious mononucleosis; the diagnosis, however, may not be straightforward, as clinical presentation may also be subtle, and abdominal ultrasonography, which is often used as a first-line imaging modality in pediatric EDs, has low sensitivity in this scenario and may easily miss it. Furthermore, although treatment is mainly supportive, close observation for possible complications is necessary.

The unexpected finding of a splenic infarction in a patient with infectious mononucleosis due to Epstein-Barr virus

The authors present a case of a 24-year-old man with infectious mononucleosis (IM) due to Epstein-Barr virus (EBV). Among his symptoms, he reported abdominal pain in the upper left quadrant. An abdominal ultrasound and CT revealed an extensive splenic infarction. During the acute stage of this disease, the thrombophilic screening revealed reduced free protein S and elevated factor VIII, with normalisation on re-evaluation 6 weeks later. Splenic infarction is a very rare complication of IM due to EBV but should be considered in patients presenting abdominal pain. A hypercoagulability state should be investigated. To our knowledge, this is the first described case of a splenic infarction in a patient with IM due to EBV associated with a transient reduction of protein S and elevation of factor VIII. Thus, this work promotes the importance of including these factors in the thrombophilic screening conducted during the investigation of similar cases.

Splenic infarction in a child with primary Epstein-Barr virus infection

Described herein is the case of a previously healthy 7-year-old girl who had splenic infarction. This lesion was identified 1 day after the first presentation of peri-umbilical and right upper quadrant pain. She had abnormal hepatic function and mild splenomegaly, and was diagnosed as having primary Epstein-Barr virus (EBV) infection. Coagulation profiles indicated low plasma activity of protein C (49%) and protein S (47%), which normalized 3 weeks later. Hypercoagulability in transient protein C and protein S deficiency might contribute to the development of splenic infarction in infectious mononucleosis.

Splenic infarction as a rare complication of infectious mononucleosis due to Epstein-Barr virus infection in a patient with no significant comorbidity: case report and review of the literature

We report the case of a 17-y-old boy diagnosed with infectious mononucleosis due to Epstein-Barr virus infection who complained of left upper quadrant pain. A magnetic resonance imaging scan showed a splenic infarct in the enlarged spleen. Other causes of splenic infarction were excluded. Thus, infectious mononucleosis may cause splenic infarction in patients without other comorbidities.

Q Fever with transient antiphospholipid antibodies associated with cholecystitis and splenic infarction

We describe a case of Q fever associated with the transient presence of antiphospholipid antibodies in a 9-year-old boy presenting with acalculous cholecystitis and splenic infarction. Antiphospholipid antibodies are commonly associated with acute Q fever in adults but have previously been thought to be of little clinical significance. Recent data suggest that antiphospholipid antibodies may be responsible for certain clinical manifestations of acute Q fever.

Massive splenic infarction in children with sickle cell anemia and the role of splenectomy

BACKGROUND

Massive splenic infarction (MSI) is a very rare condition. Few reports of splenic infarction of various etiologies including hematological and non-hematological causes have been published. On the other hand, MSI in patients with sickle cell anemia (SCA) is extremely rare. This report describes our experience with 15 children with SCA and MSI outlining aspects of presentation, diagnosis and management.

PATIENTS AND METHODS

The records of all children with MSI were retrospectively reviewed for age at diagnosis, sex, clinical features, precipitating factors, investigations, management and outcome.

RESULTS

15 children (11 M: 4 F) with SCA were treated for MSI. Their mean age was 10.9 years (6-17 years). All presented with severe left upper quadrant abdominal pain. In nine, this was associated with nausea and vomiting. Three were febrile and all had a tender splenomegaly. Their mean hemoglobin was 8.2 g/dl (5.7-11.3 g/dl), mean WBC was 10.97 × 10(3) mm(-3) (3.6 × 10(3)-22.3 × 10(3) mm(-3)) and mean platelet count was 263.3 × 10(3) mm(-3) (40 × 10(3)-660 × 10(3) mm(-3)). In seven, there was a precipitating cause including high altitude in two, acute chest syndrome in two, septicemia in two and severe vasooclusive crisis in one. Abdominal ultrasound and CT scan confirmed the diagnosis of MSI which involved more than half of the spleen in 12 and whole spleen in 3. All were treated with IV fluids, analgesia and blood transfusion where appropriate. Eleven had splenectomy because of persistent abdominal pain, three developed splenic abscess and underwent splenectomy and one settled on conservative treatment. Histology confirmed the diagnosis of splenic infarction in 11 and infarction with abscess in the remaining 3.

CONCLUSION

MSI is extremely rare in children with SCA. It can develop spontaneously or precipitated by other factors namely high altitude, acute chest syndrome and severe stress. Most reported cases of splenic infarction are small in size, focal and can be treated conservatively. MSI, on the other hand, may necessitate splenectomy for persistent symptoms or in case of complications, such as abscess formation.

Review: Viral infections and mechanisms of thrombosis and bleeding

Viral infections are associated with coagulation disorders. All aspects of the coagulation cascade, primary hemostasis, coagulation, and fibrinolysis, can be affected. As a consequence, thrombosis and disseminated intravascular coagulation, hemorrhage, or both, may occur. Investigation of coagulation disorders as a consequence of different viral infections have not been performed uniformly. Common pathways are therefore not fully elucidated. In many severe viral infections there is no treatment other than supportive measures. A better understanding of the pathophysiology behind the association of viral infections and coagulation disorders is crucial for developing therapeutic strategies. This is of special importance in case of severe complications, such as those seen in hemorrhagic viral infections, the incidence of which is increasing worldwide. To date, only a few promising targets have been discovered, meaning the implementation in a clinical context is still hampered. This review discusses non‐hemorrhagic and hemorrhagic viruses for which sufficient data on the association with hemostasis and related clinical features is available. This will enable clinicians to interpret research data and place them into a perspective. J. Med. Virol. 84:1680–1696, 2012. © 2012 Wiley Periodicals, Inc.

Antiphospholipid antibodies during infectious mononucleosis and their long term clinical significance

BACKGROUND

The prevalence of antiphospholipid antibodies (aPLs) during acute Epstein-Barr virus (EBV) infection may be as high as 30-60%. The role of these autoantibodies in the development of antiphospholipid syndrome (APS) is not clear.

OBJECTIVE

To investigate the prevalence, persistence and clinical significance of aPLs in a series of patients diagnosed with acute EBV infection.

STUDY DESIGN

A cohort of 94 patients aged 15 or older, recently diagnosed with acute EBV was retrieved. Serum samples obtained during diagnosis were tested for the presence of aPLs and anti-β2GP antibodies. Patients with positive sera for aPLs were assessed for the persistence of aPLs and the development of APS.

RESULTS

The prevalence of aPLs among 94 patients with acute EBV was 37.2%. Five of 27 available serum samples were also positive for anti-β2 glycoprotein (anti-β2GP) antibodies. Repeat testing for aPLs after a median of 21 months post acute infection (range 13-50 months) was performed in 17 of the 35 patients with positive aPL test. All 17 patients were found negative for aPL-IgG antibodies. Two of them had positive aPL-IgM antibodies and positive anti-β2GP antibodies. None of the patients who had positive aPLs experienced any manifestations of APS.

CONCLUSION

The disappearance of aPLs in the majority of the patients after acute EBV infection, along with the absence of consistent clinical findings, suggests that the detection of aPLs during acute EBV is not associated with the development APS over time.

Identification of splenic infarction by emergency department ultrasound

BACKGROUND

Splenic rupture or infarction can occur secondary to acute infectious mononucleosis. Patients with abdominal pain and known or suspected infectious mononucleosis mandate evaluation for these complications, which can have significant morbidity or mortality.

CASE REPORT

An 18-year old man presented to the emergency department (ED) with a 2-day history of left upper quadrant abdominal pain. He had been diagnosed with mononucleosis 4 days before his ED presentation. Physical examination was notable for focal left upper quadrant tenderness. The treating physician's principal diagnostic considerations were splenic rupture or infarction secondary to mononucleosis. Point-of-care ultrasound was performed by the emergency physician, demonstrating multiple hypoechoic areas in the splenic parenchyma with absent Doppler flow, consistent with multiple splenic infarcts. The patient was admitted for observation, managed conservatively, and had an uneventful course.

CONCLUSION

Emergency ultrasound of the spleen can allow rapid diagnosis of splenic infarction and exclusion of splenic rupture in a patient at risk for splenic pathology.

Splenic infarction, warm autoimmune hemolytic anemia and antiphospholipid antibodies in a patient with infectious mononucleosis

An 18-year-old woman with infectious mononucleosis developed splenic infarction and severe anemia. Evaluation of her anemia revealed a warm autoantibody and a persistently prolonged partial thromboplastin time that ultimately led to the identification of antiphospholipid antibodies. Although the warm autoantibody disappeared after 2 months, the antiphospholipid antibodies remained persistently positive. To our knowledge, this is the first case report in the literature of this specific constellation of findings, with infectious mononucleosis, warm antibody hemolytic anemia, splenic infarction and persistently positive, high-titer antiphospholipid antibodies occurring in an individual patient.

Splenic infarction in a patient with autoimmune hemolytic anemia and protein C deficiency

Splenic infarction is most commonly caused by cardiovascular thromboembolism; however, splenic infarction can also occur in hematologic diseases, including sickle cell disease, hereditary spherocytosis, chronic myeloproliferative disease, leukemia, and lymphoma. Although 10% of splenic infarction is caused by hematologic diseases, it seldom accompanies autoimmune hemolytic anemia (AIHA). We report a case of a 47-year-old woman with iron deficiency anemia who presented with pain in the left upper abdominal quadrant, and was diagnosed with AIHA and splenic infarction. Protein C activity and antigen decreased to 44.0% (60-140%) and 42.0% (65-140%), respectively. Laboratory testing confirmed no clinical cause for protein C deficiency, such as disseminated intravascular coagulation, sepsis, hepatic dysfunction, or acute respiratory distress syndrome. Protein C deficiency with splenic infarction has been reported in patients with viral infection, hereditary spherocytosis, and leukemia. This is a rare case of splenic infarction and transient protein C deficiency in a patient with AIHA.

Involvement of the contact phase and intrinsic pathway in herpes simplex virus-initiated plasma coagulation

SUMMARY BACKGROUND

A hemostatic response to vascular injury is initiated by the extrinsic pathway of coagulation and amplified by the intrinsic pathway. We previously reported that purified herpes simplex virus type-1 (HSV1) has constitutive extrinsic pathway tissue factor (TF) and anionic phospholipid on its surface derived from the host cell, and can consequently bypass strict cellular control of coagulation.

OBJECTIVE

The current work addresses the hypothesis that HSV1-induced plasma coagulation also involves intrinsic pathway, factor VIII (FVIII), and upstream contact activation pathway, factor XII (FXII).

RESULTS

HSV1-initiated clotting was accelerated when purified FVIII was added to FVIII-deficient plasma and in normal plasma attenuated by an inhibitory anti-FVIII antibody (Ab). High HSV1 concentrations predictably reduced the effect of FVIII due to the availability of excess viral TF. To further define TF-independent clotting mechanisms initiated by HSV1, the extrinsic pathway was disabled using factor VII-deficient plasma. The intrinsic pathway is triggered by activation of FXII associated with surface-bound kallikrein, which subsequently activates factor XI. Here we found that an inhibitor of activated FXII, corn trypsin inhibitor, and anti-FXII, anti-kallikrein and anti-FXI Abs inhibited HSV1-initiated clotting. HSV1-enhanced activation of purified FXII was confirmed by Western blot, but required prekallikrein.

CONCLUSION

The current work shows that HSV1 can trigger and amplify coagulation through the contact phase and intrinsic pathway, and suggests an additional mechanism that may contribute to vascular pathology.

Splenic infarction: 10 years of experience

OBJECTIVE

The aim of this study was to study the clinical presentation of splenic infarction.

METHODS

A retrospective examination of files during a 10-year period was conducted. Only computed tomography-proven diagnoses of splenic infarction were included. Signs, symptoms, medical history, and results of investigation were recorded.

RESULTS

We found 49 episodes of acute splenic infarction. Abdominal or left flank pain was the most common symptoms (80%), and left upper quadrant tenderness was the most common sign (35%). Splenic infarction was the presenting symptom of underlying disease in 16.6% of the patients. Based on the computed tomography results, ultrasound was diagnostic only in 18% of patients. There was no in-hospital mortality or serious complications.

DISCUSSION

We present, to the best of our knowledge, the largest series of patients with splenic infarction diagnosed on clinical and radiological grounds. Awareness of the diagnostic possibility of splenic infarction in a patient with unexplained abdominal pain is important because it can be the presenting symptom of potentially fatal diseases.

Glandular fever and pulmonary artery thrombosis in a paraplegic patient, who had undergone splenectomy for splenic trauma sustained along with spinal cord injury: misdiagnosed initially as urine infection and later as lymphoma when CT scan revealed enlarged lymph nodes: a case report

Background

A 36-year-old male sustained fracture of first lumbar vertebra, splenic tear and paraplegia in a motorcycle accident in 2001; splenectomy was performed.

Case presentation

In 2008, he presented with temperature and feeling rough. With a diagnosis of urine infection, he was prescribed ciprofloxacin, followed by trimethoprim, amoxicillin, and gentamicin, as temperature did not subside. White cell count was 21.2 × 10⁹/L; lymphocytes were 13.05 × 10⁹/L (1.00 – 4.00). Therefore, computerised tomography (CT) of chest and abdomen was performed. Thrombus was present in pulmonary arteries bilaterally involving the lobar and segmental branches. Enlarged lymph nodes were seen in axillae, chest, abdomen and inguinal regions. Radiological diagnosis was lymphoma. Cell marker showed an excess of large granular lymphocytes and activated lymphocytes. The Glandular Fever Slide Test was positive. Subsequently, Paul Bunnell test was also positive. Epstein Barr virus serology was consistent with recent Epstein Barr virus infection. Antibiotic was omitted; enoxaparin was prescribed for pulmonary artery thrombosis.

Conclusion

Learning points from this case: (1) Although routine administration of antibiotic to a spinal cord injury patient with pyrexia may be acceptable in outpatient setting, other possibilities such as infection by multi-drug resistant organism, viral infection, venous or, arterial thrombosis should be considered if a patient does not respond promptly to antibacterial therapy. (2) When full blood count showed lymphocytosis (comprising > 50% of white blood cells) with atypical morphology, lymphocyte surface markers, Paul Bunnell test, and Epstein Barr virus serology should be performed. These tests would have led to a diagnosis of infectious mononucleosis, and abdominal imaging studies could have been avoided. (3) Lymphoid hyperplasia is the hallmark of infectious mononucleosis; therefore, we should have suspected glandular fever rather than lymphoma when CT scan revealed enlarged lymph nodes in abdomen, mediastinum, axillae and inguinal regions in this patient, who had lymphocytosis with atypical morphology. (4) A soft tissue mass, situated inferior to left hemidiaphragm in this asplenic patient, was misinterpreted as lymph nodes; review of CT led to the correct diagnosis of splenunculus. (5) Acute infection with Epstein Barr virus may lead to transient induction of anti-phospholipid antibodies, which can cause vascular thrombosis. (6) This case illustrates the value of reviewing test results and discussion with senior doctors, as these measures help to recognize medical errors and improve patient care.

Splenic infarction in a patient hereditary spherocytosis, protein C deficiency and acute infectious mononucleosis

Splenic infarction is a common cause of left upper quadrant pain and must be suspected in patients with hematologic or thromboembolic conditions and signs of localized or systemic inflammation. Although several mechanisms have been proposed for splenic infarction in patients with various hematologic disorders, hereditary spherocytosis (HS) is usually not associated with an increased risk for thromboembolic events. We report a 13-year-old male with HS who was referred to our hospital with a 4-day history of fever and left upper quadrant pain. Ultrasound scans and magnetic resonance imaging showed lesions suggestive of splenic infarction. Initially, antibiotic treatment was started because secondary infection was suspected. However, 1 week after admission the patient developed typical clinical signs of acute infectious mononucleosis. Further laboratory work up confirmed the diagnosis of acute Epstein-Barr virus infection and additionally revealed protein C deficiency. This association has not been reported previously and may have contributed to the development of splenic infarction. Since infectious mononucleosis is a common cause for clinical consultations in adolescence, physicians caring for children with hematologic disorders should be particularly aware of those possible complications.

[Antiphospholipid antibodies, antiphospholipid syndrome and viral infections]

Since the association between antiphospholipid antibodies and syphilis was first described, many other viral, bacterial and parasitic infections have been shown to induce antiphospholipid antibodies, notably anticardiolipin antibodies. These aPL are usually associated neither with anti-beta2 glycoprotein I antibodies (anti-beta2-GPI) nor with thrombotic events, even if cases of arterial and deep venous thrombosis have been reported in such circumstances. A literature review shows that anticardiolipin antibodies occur frequently in viral infections, particularly in HIV (49.8%), HBV (24%) and HCV (20%). The prevalence of anti-beta2 glycoprotein I antibodies (anti-beta2GPI) is lower (HCV: 1.7%, HIV: 5.6%, HBV: 3.3%) and there is no demonstrated association with a risk of thrombotic events or hematological manifestations defining antiphospholipid syndrome (APS). Regarding other viral infections, including viral hepatitis A, herpes virus (CMV, EBV, VZV), parvovirus B19 and HTLV-1 infections, only a few studies are available but data confirm the high prevalence of antiphospholipid antibodies at the acute phase. Finally, antiphospholipid antibodies, mainly anticardiolipin, are frequently associated with viral infections. Their presence may probably reflect an intense or chronic antigenic stimulation of the immune system. However, their evolution under antiviral therapy and correlation with the quality of the virological control and/or the immune restoration remain to be determined.

Infections and autoimmunity: a panorama

For more than 2,000 years, it was thought that malignant spirits caused diseases. By the end of nineteenth century, these beliefs were displaced by more modern concepts of disease, namely, the formulation of the “germ theory,” which asserted that bacteria or other microorganisms caused disease. With the emergence of chronic degenerative and of autoimmune diseases in the last century, the causative role of microorganisms has been intensely debated; however, no clear explanatory models have been achieved. In this review, we examine the current available literature regarding the relationships between infections and 16 autoimmune diseases. We critically analyzed clinical, serological, and molecular associations, and reviewed experimental models of induction of and, alternatively, protection from autoimmune diseases by infection. After reviewing several studies and reports, a clinical and experimental pattern emerges: Chronic and multiple infections with viruses, such as Epstein–Barr virus and cytomegalovirus, and bacteria, such as H. pylori, may, in susceptible individuals, play a role in the evolvement of autoimmune diseases. As the vast majority of infections pertain to our resident microbiota and endogenous retroviruses and healthy carriage of infections is the rule, we propose to focus on understanding the mechanisms of this healthy carrier state and what changes its configurations to infectious syndromes, to the restoration of health, or to the sustaining of illness into a chronic state and/or autoimmune disease. It seems that in the development of this healthy carriage state, the infection or colonization in early stages of ontogenesis with key microorganisms, also called ‘old friends’ (lactobacilli, bifidobacteria among others), are important for the healthy living and for the protection from infectious and autoimmune syndromes.

Antiphospholipid antibodies, antiphospholipid syndrome and infections

Since the association between antiphospholipid antibodies (aPL) and syphilis was first described, many other viral, bacterial and parasitic infections have been shown to induce antiphospholipid antibodies, notably anticardiolipin antibodies (aCL). A review of the literature shows that while aCL occur frequently in viral infections, particularly in HIV (49.75%), HBV (24%) and HCV (20%), it is very rarely associated with anti-beta2 glycoprotein I antibodies (anti-beta2GPI) and is not correlated with thrombosis risk or hematological manifestations of the antiphospholipid syndrome (APS). Concerning bacterial infections, aCL is often present in leprosy (42.7%), where it is frequently associated with the presence of anti-beta2GPI (44.8%), and in syphilis infections (8 to 67%), though without correlation with thrombotic events. Though few individual patients with unequivocal infection-induced aPL satisfy criteria for APS, the lack of statistical association with thrombotic events strongly argues against the identification of a true APS subset in this context. However, physicians should keep in mind the fact that an infection, generally bacterial, in patients with confirmed APS, may lead to catastrophic antiphospholipid syndrome with a possible fatal outcome.

Splenic infarction after Epstein-Barr virus infection in a patient with hereditary spherocytosis

We describe the first patient with hereditary spherocytosis (HS) known to have developed splenic infarction following infectious mononucleosis (IM). An 18-year-old Japanese man was referred to our hospital in November 2004 because of continuous fever and icterus. He had undergone cholecystectomy at the age of 14 years. On patient admission in November 2004, a physical examination showed marked hepatosplenomegaly, icterus, and jaundice. He had a white blood cell count of 14.9 x 10(9)/L with 9.5% atypical lymphocytes, a red blood cell count of 2.93 x 10(12)/L, and a hemoglobin concentration of 7.8 g/dL. Microspherocytes were observed in the patient's peripheral blood smear, and immunoglobulin M antibody to Epstein-Barr virus (EBV) viral capsid antigen was detected. The patient's diagnosis was HS with IM. On day 4 of admission, the patient complained of severe abdominal pain. Abdominal computed tomography scanning revealed findings of splenic infarction. Two months after the occurrence of splenic infarction, a splenectomy was performed. A pathohistologic examination of the resected spleen revealed no evidence of thrombosis or arterial occlusion. We assume that the cause of splenic infarction was insufficient blood flow to oxygenate the entire spleen during the acute enlargement of the spleen.

Antiphospholipid antibodies in response to infection

An association between infections and antiphospholipid antibodies (aPL) has been reported in several epidemiologic and experimental studies. Infection-induced aPL have been traditionally regarded as transient and were generally not associated with clinical features of antiphospholipid syndrome. The distinction between autoimmune and postinfectious aPL on the basis of requirement of binding cofactor is not absolute, and in recent years, several reports demonstrated that some patients can produce pathogenic antibodies in response to infection. Infections most frequently associated with antiphospholipid syndrome include parvovirus B19, cytomegalovirus, varicella-zoster virus, HIV, streptococcal and staphylococcal infections, gram-negative bacteria, and Mycoplasma pneumoniae.

Mycoplasma pneumoniae, splenic infarct, and transient antiphospholipid antibodies: a new association?

We report 2 children with Mycoplasma pneumoniae pulmonary infection with splenic infarcts and transient antiphospholipid antibodies. This association has not been reported previously.