Vasculitis and systemic infections

Clinical Manifestations of Non-Congenital CMV Infection in Infants and Immunocompetent Children: Review of Cases from the Past Decade

Cytomegalovirus (CMV), the largest of the herpes viruses, is a widespread virus that commonly infects people of all ages. CMV can cause a spectrum of clinical manifestations, ranging from asymptomatic infection to severe disease, particularly in immunocompromised hosts. However, postnatal and acquired CMV infections in immunocompetent children remain under-documented in the literature. In this review, we examine studies published over the past decade to explore the clinical manifestations of CMV infections in the pediatric population, focusing on the variety of symptoms and the severity with which the infection can present. Papers published between 1 January 2014 and 2 December 2024 were selected from PubMed/MEDLINE, Embase, Scopus, and Web of Science. The search was conducted using the following keywords: "cytomegalovirus", "child", and "immunocompetent". The target population ranged from 0 to 17 years of age, with congenital and perinatal infections excluded. Despite the clinical significance of CMV in immunocompetent infants and children, there is a lack of consensus on the use and duration of antiviral therapy. This article aims to enhance clinicians' understanding of the various presentations of CMV infection in immunocompetent children, with the goal of facilitating earlier diagnosis and appropriate management. The reviewed papers indicated that postnatal CMV results in liver symptoms in 67% of cases, followed by hematological disorders and gastrointestinal pathology. In older children, primary infection leads to liver disease in 51% of cases, with greater neurological and pulmonary involvement compared to that in infants. By highlighting the wide-ranging clinical effects of CMV, we hope to improve physicians' ability to recognize and subsequently treat this often overlooked condition in pediatric patients.

Surgical intervention of Takayasu's arteritis with supraaortic arterial occlusive disease and critical ischemia of upper extremity: A case report

Type I Takayasu's arteritis is a rare form of large vessel vasculitis with an unknown etiopathogenesis. It is characterized by progressive chronic inflammation and occlusive thromboaortopathy affecting the aorta and its main branches. Type I Takayasu's arteritis predominantly affects women and is most commonly observed in their third decade of life. In this report, we present the case of a 32-year-old female patient who exhibited severe long-segment stenosis in the left common carotid artery and total occlusion of the left subclavian artery. The patient experienced significant ischemic symptoms of the left upper extremity and had previously been diagnosed with Takayasu's arteritis, being followed up under maintenance corticosteroid therapy. To address these complications, we conducted a surgical bypass using a prosthetic graft. The graft was inserted intrathoracically, extending from the patient's ascending aorta to both the left common carotid artery and the left distal subclavian artery. This approach was designed to closely mimic anatomical routes, promoting optimal graft patency. In the context of this case, we highlight the importance of surgical intervention in alleviating ischemia and explore potential surgical alternatives for treating patients with Takayasu's arteritis involving the supraaortic region.

Childhood Cerebral Vasculitis : A Multidisciplinary Approach

Cerebral vasculitis is increasingly recognized as a common cause of pediatric arterial stroke. It can present with focal neurological deficits, psychiatric manifestations, seizures, and encephalopathy. The etiopathogenesis of childhood cerebral vasculitis (CCV) is multifactorial, making an inclusive classification challenging. In this review, we describe the common and uncommon CCV with a comprehensive discussion of etiopathogenesis, the role of various imaging modalities, and advanced techniques in diagnosing CCV. We also highlight the implications of relevant clinical, laboratory, and genetic findings to reach the final diagnosis. Based on the clinicoradiological findings, a stepwise diagnostic approach is proposed to facilitate CCV diagnosis and rule out potential mimics. Identification of key clinical manifestations, pertinent blood and cerebrospinal fluid results, and evaluation of central nervous system vessels for common and disease-specific findings will be emphasized. We discuss the role of magnetic resonance imaging, MR angiography, and vessel wall imaging as the imaging investigation of choice, and reservation of catheter angiography as a problem-solving tool. We emphasize the utility of brain and leptomeningeal biopsy for diagnosis and exclusion of imitators and masqueraders.

Overview of infections as an etiologic factor and complication in patients with vasculitides

Vasculitides, a form of inflammatory autoimmune disease targeting the vessels, constitute an entity with significant morbidity and mortality. Infections have long been associated with vasculitides as a result of the incident immunosuppression following treatment induction and maintenance. Several microbial pathogens have been described as etiologic factors of infections in this patient population according to the type of vessels affected. Intense research has also been recently conducted in the interplay between vasculitides and certain viral infections, namely human immunodeficiency virus and severe acute respiratory syndrome coronavirus 2. Of note, a plethora of scientific evidence is available regarding the role of infections as triggering factors for vasculitides. Among the main mechanisms implicated in this direction are the activation of B and T cells, the direct endothelial insult, the immune complex-mediated vascular injury, and the cell-mediated, type IV hypersensitivity vessel damage. Therefore, this review aims to summarize all the available evidence concerning this bidirectional interplay between infections and vasculitides.

Infection is associated with increased risk of MPO- but not PR3-ANCA-associated vasculitis

OBJECTIVES

To determine whether development of ANCA-associated vasculitis (AAV) shows a relationship with a prior infection and if prior infection affects disease characteristics and outcome.

METHODS

All incident cases of AAV diagnosed in a defined region of Sweden from 2000 through 2016 were identified. For each case, 10 individuals from the general population, matched for age, sex and area of residence, were selected. Infections occurring in AAV patients and controls prior to the date of AAV diagnosis (index date for respective controls) were identified using an administrative database. Conditional logistic regression models were used to calculate odds ratios (OR) of developing AAV. Occurrence, clinical characteristics and outcome of AAV were analysed with respect to prior infection.

RESULTS

Two-hundred and seventy patients with AAV (48% female) and 2687 controls were included. Prior to diagnosis/index date, 146 (54%) AAV patients had been diagnosed with infection vs 1282 (48%) controls, with OR for AAV 1.57 (95% CI 1.18, 2.19) in those with infections of the upper respiratory tract and 1.68 (1.02, 2.77) in those with pneumonia. Difference from controls was significant in patients with MPO-ANCA 1.99 (95% CI 1.25, 3.1) but not in those with PR3-ANCA 1.0 (0.61, 1.52). Patients with prior infection showed higher disease activity at AAV diagnosis. No differences in disease characteristics, comorbidities or outcome in those with and without prior infections were observed.

CONCLUSIONS

Respiratory tract infections are positively associated with development of MPO- but not PR3-ANCA vasculitis. Prior infection is associated with higher disease activity at AAV diagnosis.

Cerebellar infarction requiring surgical decompression in patient with COVID 19 pathological analysis and brief review

BACKGROUND

This report and literature review describes a case of a COVID-19 patient who suffered a cerebellar stroke requiring neurosurgical decompression. This is the first reported case of a sub-occipital craniectomy with brain biopsy in a COVID-19 patient showing leptomeningeal venous intimal inflammation.

CLINICAL DESCRIPTION

The patient is a 48-year-old SARS-COV-2 positive male with multiple comorbidities, who presented with fevers and respiratory symptoms, and imaging consistent with multifocal pneumonia. On day 5 of admission, the patient had sudden change in mental status, increased C-Reactive Protein, ferritin and elevated Interleukin-6 levels. Head CT showed cerebral infarction from vertebral artery occlusion. Given subsequent rapid neurologic decline from cerebellar swelling and mass effect on his brainstem emergent neurosurgical intervention was performed. Brain biopsy found a vein with small organizing thrombus adjacent to focally proliferative intima with focal intimal neutrophils.

CONCLUSION

A young man with COVID-19 and suspected immune dysregulation, complicated by a large cerebrovascular ischemic stroke secondary to vertebral artery thrombosis requiring emergent neurosurgical intervention for decompression with improved neurological outcomes. Brain biopsy was suggestive of inflammation from thrombosed vessel, and neutrophilic infiltration of cerebellar tissue.

Cytomegalovirus-Induced Polyarteritis Nodosa in a Liver Transplant Recipient

Polyarteritis nodosa (PAN) is a necrotizing vasculitis that has been associated with viral infections, especially hepatitis B virus. We hereby report a case of tissue-invasive cytomegalovirus (CMV)-induced PAN in a liver transplant recipient presenting with acute kidney injury and active urinary sediment. Treatment directed against both PAN and CMV resulted in improvement in kidney function, normalization of urinary indices and resolution of the CMV infection. There was no recurrence of either PAN or CMV after a 3-year follow-up period.

Epstein-Barr virus-related cutaneous necrotizing vasculitis in a girl heterozygous for factor V Leiden

BACKGROUND

Necrotizing vasculitides are basically characterized by vessel wall neutrophil infiltration and necrosis and they can occur as a primary process or secondary to an underlying disease. Although Henoch-Schönlein purpura (HSp) is the more frequent primary vasculitis in childhood, sometimes it has to be distinguished from other secondary vasculitides induced by infections, drugs, vaccines, or immune-mediated disorders.

MAIN OBSERVATIONS

We report a case of a 14-year-old girl with cutaneous necrotizing vasculitis, appearing in the course of acute Epstein-Barr virus infection. Physical examination revealed highly aching erythematous-purple lesions with reticular edges localized on the back of feet. Pain was non-responsive to ibuprofen and required administration of tapentadol and pregabalin. The patient was also heterozygous for factor V Leiden that might have contributed to the development of cutaneous painful lesions.

CONCLUSIONS

To our knowledge this is the first documented pediatric case of necrotizing vasculitis associated with acute EBV infection in a girl heterozygous for factor V Leiden. In this patient the severity of skin manifestations might have been influenced by the concomitant factor V Leiden, which gave rise to hypercoagulability and occlusive vasculopathy with markedly severe pain, a symptom rather infrequent in other childhood vasculitides.

Echocardiographic Evaluation of Coronary Abnormalities and Cardiac Function in a Murine Model of Kawasaki Disease Using High-frequency Ultrasound

Background:

Murine model of coronary arterial inflammation has been widely accepted as an animal model of and used in Kawasaki disease (KD). This study sought to evaluate the developmental changes of coronary arteries and cardiac function in a murine model of KD with a high-frequency ultrasound system and to provide evidence for the preparation of the model of KD.

Methods:

Lactobacillus casei cell wall extract was prepared and injected into C57BL/6 mice intraperitoneally (i.p.) to induce KD. A total of 120 mice were grouped into three groups. The intravenous immunoglobulin (IVIG) treatment group was i.p. injected with IVIG (2 g/kg), while the KD model and normal control groups were i.p. injected with 0.5 ml of phosphate buffered solution on day 5. All high-resolution echocardiography detection of mouse heart was performed by the same senior technician. Animal echocardiography was performed by measuring the coronary artery dimensions and cardiac function on days 0, 7, 14, 28, and 56 (high-resolution small animal ultrasound [Vevo770 pattern; VisualSonic, Canada] with broadband probe [RMVTM707B; frequency, 30 mHz; depth of focus, 1.2 cm]) which were measured and analyzed with Vevo770 software.

Results:

Pathological studies revealed focal inflammatory infiltrate asymmetrically distributed around the coronary artery trunk in the KD model group. Echocardiographic study including coronary dimension and cardiac function measurements was successfully performed in all subjects. The KD model and IVIG treatment groups showed left coronary artery dilation on days 7, 14, 28, and 56. The diameter of left coronary artery in the KD model group (0.53 ± 0.09 mm; 0.36 ± 0.07 mm; 0.34 ± 0.05 mm; 0.34 ± 0.04 mm) was significantly larger than those of IVIG treatment group (0.22 ± 0.02 mm; 0.28 ± 0.03 mm; 0.26 ± 0.03 mm; 0.27 ± 0.05 mm; 0.26 ± 0.03 mm; all P < 0.01) and the normal control group (0.21 ± 0.02 mm; 0.22 ± 0.03 mm; 0.22 ± 0.02 mm; 0.23 ± 0.02 mm; 0.27 ± 0.04 mm; all P < 0.01) on days 7, 14, 28, and 56. No significant differences were observed in the measurements of cardiac function among the groups on days 0, 7, 14, 28, and 56 (all P > 0.05).

Conclusions:

Echocardiography could identify the consecutive changes of coronary artery in KD mice. Echocardiography is more convenient and direct in evaluating the coronary abnormalities in this animal model.

F-18 FDG PET/CT imaging of cardiac and vascular inflammation and infection

INTRODUCTION

Inflammation forms an important core of the aetiopathogenic process involved in many diseases affecting the heart and the blood vessels. These diseases include infections as well as inflammatory non-infectious cardiovascular conditions. The common feature of this is invasion of the heart or blood vessel by inflammatory cells. F-18 2-fluoro 2-deoxy-D glucose (FDG) is an analogue of glucose and like glucose it is taken up by activated inflammatory cells that accumulate at the site of infection. This has formed the basis of the use of F-18 FDG PET/CT in the non-invasive evaluation of human inflammatory diseases.

SOURCES OF DATA

This review is based on the published academic articles as well as our clinical experience.

AREAS OF AGREEMENT

F-18 FDG PET/CT is a useful imaging modality in the evaluation of cardiovascular inflammatory disorders. Accumulation and distribution of F-18 FDG at the site of inflammation/infection corresponds to severity of the inflammation/infection and extent of involvement.

AREAS OF CONTROVERSY

Most studies evaluating utility of F-18 FDG PET/CT in imaging cardiovascular inflammation are small observational studies hence are potentially prone to bias.

GROWING POINTS

Being a hybrid metabolic and morphologic imaging technique, F-18 FDG PET/CT offers combined advantage of complementary anatomic and metabolic information in disease process. This makes it a useful modality in the diagnosis, determination of extent of disease, prognostication as well as treatment monitoring.

AREAS TIMELY FOR DEVELOPING RESEARCH

Larger prospective studies are needed to validate the superiority of F-18 FDG PET/CT imaging over conventional anatomic imaging modalities.

[Childhood vasculitis]

BACKGROUND

The primary vasculitides are rare conditions in childhood. The most common disease subtypes are Schönlein-Henoch purpura and Kawasaki's syndrome, which frequently have a self-limiting course. In the majority of vasculitides, the etiology remains unknown. Environmental exposure, including infections, is suspected to trigger an autoinflammatory response in predisposed individuals.

GOAL

The aim of this review is to present the various aspects of childhood vasculitis.

MATERIALS AND METHODS

Reviews and special original papers on childhood vasculitis, published classification criteria and current therapy guidelines were reviewed and summarized.

RESULTS

The classification of vasculitides in childhood has been modified from the previous adult Chapel Hill classification for vasculitides in 2008. Most therapy recommendations for children are adapted from results of studies in adults. This review covers the current classifications, pathogenesis, clinical manifestations and therapy recommendations for children.

DISCUSSION

Although etiology and pathogenesis of many vasculitides in childhood are still unknown, clarifying diagnostic methods and effective therapeutic options are available. The knowledge about various forms of disease manifestation may contribute to an early diagnosis and timely initiation of treatment, which may prevent devastating irreversible impairment.

Updates in Pathophysiology, Diagnosis and Management of Takayasu Arteritis

BACKGROUND

Takayasu arteritis (TA) is a rare, systemic, inflammatory vasculitis of granulomatous nature, and still of unknown etiology. It mainly involves the aorta and its major branches and is more commonly seen in women of childbearing age and Asians. TA leads to stenosis, occlusion, or aneurysmal degeneration of large arteries, and its pathogenesis seems to be mainly due to an abnormal cell-mediated immunity, although other molecular and genetic abnormalities may contribute. The diagnosis and treatments lie on clinical and arteriographic findings. Because of its fluctuating course, both clinical scores and biomarkers are currently evaluated. The aim of this review is to report a comprehensive and methodologically robust state of the art about Takayasu arteritis, including the latest data and evidences in the definition, epidemiology, pathogenesis and etiology, clinical manifestations and classification, diagnosis, assessment of disease activity and progression, biomarkers, and treatment.

METHODS

We searched all publications addressing definition, epidemiology, pathogenesis, etiology, classification, diagnosis, biomarkers, and treatment of TA. Randomized trials, cohort studies, and reviews were contemplated to give a breadth of clinical data. PubMed and Scopus were searched from August 2010 to November 2015.

RESULTS

Of the 3,056 records found, 267 matched our inclusion criteria. After reading the full-text articles, we decided to exclude 169 articles because of the following reasons: (1) no innovative or important content; (2) no multivariable analysis; (3) insufficient data; (4) no clear potential biases or strategies to solve them; (5) no clear end-points; and (6) inconsistent or arbitrary conclusions. The final set included 98 articles.

CONCLUSIONS

This review presents the last updates in all fields of Takayasu arteritis. Still today, large areas of TA pathogenesis and disease-activity assessment need to be further investigated to better treat patients with TA.

Central nervous system vasculitis in adults and children

Primary angiitis of the central nervous system (PACNS) is an inflammatory brain disease targeting the cerebral blood vessels, leading to a wide spectrum of signs and symptoms, including neurologic deficits, cognitive dysfunction, and psychiatric symptoms. The inflammation could be reversible if diagnosed and treated early. The diagnosis requires the careful consideration and rapid evaluation of systemic underlying conditions and disease mimics. The differential diagnosis is distinctly different for angiography-positive and -negative PACNS subtypes and differs depending on age, so there is childhood PACNS or adult PACNS. Distinct disease subtypes have been described, with characteristic disease course, neuroimaging findings, and histopathologic features. Novel and traditional biomarkers, including von Willebrand factor antigen and cytokine levels, can help diagnose, and define subtype and disease activity. Treatment of PACNS should be tailored to the disease subtypes and clinical symptoms. Beyond immunosuppression it should include medications to control symptoms in order to support and enhance the child's or adult's ability to actively participate in rehabilitation. The mortality of PACNS has decreased; studies determining the morbidity and its determinants are urgently needed.

Individuality, phenotypic differentiation, dormancy and 'persistence' in culturable bacterial systems: commonalities shared by environmental, laboratory, and clinical microbiology

For bacteria, replication mainly involves growth by binary fission. However, in a very great many natural environments there are examples of phenotypically dormant, non-growing cells that do not replicate immediately and that are phenotypically 'nonculturable' on media that normally admit their growth. They thereby evade detection by conventional culture-based methods. Such dormant cells may also be observed in laboratory cultures and in clinical microbiology. They are usually more tolerant to stresses such as antibiotics, and in clinical microbiology they are typically referred to as 'persisters'. Bacterial cultures necessarily share a great deal of relatedness, and inclusive fitness theory implies that there are conceptual evolutionary advantages in trading a variation in growth rate against its mean, equivalent to hedging one's bets. There is much evidence that bacteria exploit this strategy widely. We here bring together data that show the commonality of these phenomena across environmental, laboratory and clinical microbiology. Considerable evidence, using methods similar to those common in environmental microbiology, now suggests that many supposedly non-communicable, chronic and inflammatory diseases are exacerbated (if not indeed largely caused) by the presence of dormant or persistent bacteria (the ability of whose components to cause inflammation is well known). This dormancy (and resuscitation therefrom) often reflects the extent of the availability of free iron. Together, these phenomena can provide a ready explanation for the continuing inflammation common to such chronic diseases and its correlation with iron dysregulation. This implies that measures designed to assess and to inhibit or remove such organisms (or their access to iron) might be of much therapeutic benefit.

Individuality, phenotypic differentiation, dormancy and 'persistence' in culturable bacterial systems: commonalities shared by environmental, laboratory, and clinical microbiology

For bacteria, replication mainly involves growth by binary fission. However, in a very great many natural environments there are examples of phenotypically dormant, non-growing cells that do not replicate immediately and that are phenotypically 'nonculturable' on media that normally admit their growth. They thereby evade detection by conventional culture-based methods. Such dormant cells may also be observed in laboratory cultures and in clinical microbiology. They are usually more tolerant to stresses such as antibiotics, and in clinical microbiology they are typically referred to as 'persisters'. Bacterial cultures necessarily share a great deal of relatedness, and inclusive fitness theory implies that there are conceptual evolutionary advantages in trading a variation in growth rate against its mean, equivalent to hedging one's bets. There is much evidence that bacteria exploit this strategy widely. We here bring together data that show the commonality of these phenomena across environmental, laboratory and clinical microbiology. Considerable evidence, using methods similar to those common in environmental microbiology, now suggests that many supposedly non-communicable, chronic and inflammatory diseases are exacerbated (if not indeed largely caused) by the presence of dormant or persistent bacteria (the ability of whose components to cause inflammation is well known). This dormancy (and resuscitation therefrom) often reflects the extent of the availability of free iron. Together, these phenomena can provide a ready explanation for the continuing inflammation common to such chronic diseases and its correlation with iron dysregulation. This implies that measures designed to assess and to inhibit or remove such organisms (or their access to iron) might be of much therapeutic benefit.

[A review of Kawasaki disease, a perspective from the articles published in Mexico since January 1977 to May 2012]

Kawasaki disease was described in 1967 by Tomisu Kawasaki. It affects children aged between one and 5 years, and it evolves with fever and small vessel vasculitis, which leads to cardiovascular complications, including coronary aneurisms, myocarditis, valve injuries, pericardial effusion and myocardial infarction; eventually involving many others organs. The etiology actually is not well known, as the exactly pathogenic mechanisms; however, now there are important advances. If the clinical signs and symptoms are identify early and the children received treatment with aspirin and intravenous immunoglobulin, the patients evolves without sequels. The Kawasaki disease is an infrequent disease in Mexico.

T cell-macrophage interactions and granuloma formation in vasculitis

Granuloma formation, bringing into close proximity highly activated macrophages and T cells, is a typical event in inflammatory blood vessel diseases, and is noted in the name of several of the vasculitides. It is not known whether specific properties of the microenvironment in the blood vessel wall or the immediate surroundings of blood vessels contribute to granuloma formation and, in some cases, generation of multinucleated giant cells. Granulomas provide a specialized niche to optimize macrophage-T cell interactions, strongly activating both cell types. This is mirrored by the intensity of the systemic inflammation encountered in patients with vasculitis, often presenting with malaise, weight loss, fever, and strongly upregulated acute phase responses. As a sophisticated and highly organized structure, granulomas can serve as an ideal site to induce differentiation and maturation of T cells. The granulomas possibly seed aberrant Th1 and Th17 cells into the circulation, which are known to be the main pathogenic cells in vasculitis. Through the induction of memory T cells, aberrant innate immune responses can imprint the host immune system for decades to come and promote chronicity of the disease process. Improved understanding of T cell-macrophage interactions will redefine pathogenic models in the vasculitides and provide new avenues for immunomodulatory therapy.

IFN priming is necessary but not sufficient to turn on a migratory dendritic cell program in lupus monocytes

Blood monocytes from children with systemic lupus erythematosus (SLE) behave similar to dendritic cells (DCs), and SLE serum induces healthy monocytes to differentiate into DCs in a type I IFN-dependent manner. In this study, we found that these monocytes display significant transcriptional changes, including a prominent IFN signature, compared with healthy controls. Few of those changes, however, explain DC function. Exposure to allogeneic T cells in vitro reprograms SLE monocytes to acquire DC phenotype and function, and this correlates with both IFN-inducible (IP10) and proinflammatory cytokine (IL-1β and IL6) expression. Furthermore, we found that both IFN and SLE serum induce the upregulation of CCR7 transcription in these cells. CCR7 protein expression, however, requires a second signal provided by TLR agonists such as LPS. Thus, SLE serum "primes" a subset of monocytes to readily (<24 h) respond to TLR agonists and acquire migratory DC properties. Our findings might explain how microbial infections exacerbate lupus.

Juvenile polyarteritis nodosa associated with toxoplasmosis presenting as Kawasaki disease

Polyarteritis nodosa (PAN) is a vasculitis characterized by inflammatory necrosis of medium-sized arteries. Juvenile PAN and Kawasaki disease (KD) both cause vasculitis of the medium-sized arteries, and share common features. They have overlapping clinical features. Treatment should be managed according to the severity of symptoms and persistence of clinical manifestations. Herein is described the case of a 14-year-old boy first diagnosed with KD, who then fulfilled the criteria for juvenile PAN due to the development of severe myalgia, persistent fever, polyneuropathy and coronary arterial dilatation. He also had acute toxoplasmosis at the onset of vasculitis symptoms. The final diagnosis was of juvenile PAN associated with toxoplasmosis infection. Toxoplasma infection can be considered as an etiological agent for PAN and other vasculitis syndromes. Awareness of toxoplasmosis-related PAN facilitates early diagnosis, and instigation of appropriate treatment.

Cutaneous leukocytoclastic vasculitis due to Salmonella enteritidis in a child with interleukin-12 receptor beta-1 deficiency

Defects in the interleukin 12 (IL-12)/interferon gamma (IFN-γ) pathway result in Mendelian susceptibility to mycobacterial disease (MSMD). IL-12 receptor beta 1 (IL-12Rβ1) deficiency, the most common form of MSMD, is associated with weakly virulent mycobacteria and salmonella. Infections in patients with this deficiency are extraintestinal, or septicemic, recurrent infections with nontyphoid salmonellae. Here we report a case of an IL-12Rβ1 deficiency with cutaneous leukocytoclastic vasculitis due to Salmonella enteritidis.

Immune mechanisms in medium and large-vessel vasculitis

Vasculitis of the medium and large arteries, most often presenting as giant cell arteritis (GCA), is an infrequent, but potentially fatal, type of immune-mediated vascular disease. The site of the aberrant immune reaction, the mural layers of the artery, is strictly defined by vascular dendritic cells, endothelial cells, vascular smooth muscle cells and fibroblasts, which engage in an interaction with T cells and macrophages to, ultimately, cause luminal stenosis or aneurysmal wall damage of the vessel. A multitude of effector cytokines, all known as critical mediators in host-protective immunity, have been identified in vasculitic lesions. Two dominant cytokine clusters--the IL-6-IL-17 axis and the IL-12-IFN-γ axis--have been linked to disease activity. These two clusters seem to serve different roles in the vasculitic process. The IL-6-IL-17 cluster is highly responsive to standard corticosteroid therapy, whereas the IL-12-IFN-γ cluster is resistant to steroid-mediated immunosuppression. The information exchange between vascular and immune cells and stabilization of the vasculitic process involves members of the Notch receptor and ligand family. Focusing on elements in the tissue context of GCA, instead of broadly suppressing host immunity, might enable a more tailored therapeutic approach that avoids unwanted adverse effects of aggressive immunosuppression.

Primary and secondary central nervous system vasculitis

Central nervous system vasculitis is an increasingly recognized inflammatory brain disease causing devastating neurological deficits and psychiatric manifestations in previously healthy children. Primary central nervous system vasculitis represents an isolated inflammatory attack targeting the cerebral vessels. In contrast, in children with secondary central nervous system vasculitis, an underlying condition can be identified. The spectrum of childhood primary and secondary central nervous system vasculitis is rapidly expanding, as is the differential diagnosis including nonvasculitic inflammatory brain diseases and noninflammatory vasculopathies. Early recognition, rapid diagnostic evaluation, and initiation of treatment have led to improved morbidity and mortality. This review focuses on clinical, laboratory, and neuroimaging characteristics of the distinct subtypes of primary childhood central nervous system vasculitis, reports the etiology of secondary central nervous system vasculitis, provides an overview of the differential diagnosis, and reviews the current approaches in treatment.

Infectious serologies and autoantibodies in hepatitis C and autoimmune disease-associated mixed cryoglobulinemia

Mixed cryoglobulinemia (MC) syndrome is an immune complex-mediated vasculitis characterized by the clinical triad of purpura, weakness, and arthralgias, the morbidity of which is mainly related to kidney and peripheral nervous system dysfunction as well as to the development of a secondary lymphoma (Ferri et al. Autoimmun Rev 7:114-120, 2007, Lidar et al. Ann N Y Acad Sci 1173:649-657, 2009, Trejo et al. Semin Arthritis Rheum 33:19-28, 2003). MC is associated with infectious and systemic disorders, principally autoimmune and lymphoproliferative diseases. Since the 1990s, a striking association (>90%) between MC and hepatitis C virus (HCV) infection has been established (Ferri and Bombardieri 2004; Pascual et al. J Infect Dis 162:569-570, 1990). However, information regarding the etiopathogenesis of HCV-negative MC is scant (Mascia et al. Dig Liver Dis 39:61-64, 2007). We hereby present our findings, as well as previously published data, regarding the presence of antibodies against infectious agents and autoantibodies in patients with MC in an attempt to establish novel associations which may shed light on the etiopathogenesis of this disease.

Ischaemic manifestations in giant cell arteritis are associated with area level socio-economic deprivation, but not cardiovascular risk factors

OBJECTIVES

To determine whether ischaemic manifestations of GCA are associated with pre-existing hypertension, atherosclerosis or area-level socio-economic deprivation.

METHODS

We conducted an observational study of rheumatologist/ophthalmologist-diagnosed GCA in eight UK centres. The main outcome measure was ischaemic manifestations observed during active GCA: visual loss/blurring, aura, diplopia, jaw/tongue/limb claudication, cerebral/myocardial ischaemia or scalp necrosis.

RESULTS

Out of 271 patients, 222 had ischaemic manifestations. Adjusted odds ratios (ORs) for the influence of hypertension and atherosclerosis were 1.6 (95% CI 0.8, 3.1) and 1.5 (0.6, 3.5). The most striking finding was an association of ischaemic manifestations with increasing Index of Deprivation 2007 score: OR 4.2 (95% CI 1.3, 13.6) for the most-deprived quartile compared with the least-deprived quartile. Similar effect sizes were seen within each recruitment centre. Deprivation was associated with smoking and negatively associated with previous polymyalgia. However, neither of these variables, nor hypertension or atherosclerosis, appeared responsible for mediating the effect of deprivation on ischaemic complications. Smoking was not associated with ischaemic manifestations. Median symptom duration before treatment was 30 days; after adjusting for symptom duration, the OR for ischaemic complications was 3.2 (95% CI 1.0, 10.8) for the most-deprived quartile compared with the least-deprived quartile.

CONCLUSIONS

In GCA, area-level socio-economic deprivation was associated with ischaemic manifestations: this was not mediated by traditional cardiovascular risk factors. These findings are novel and require replication. Delay between first symptoms and treatment may play a role. Public awareness campaigns about GCA should aim especially to engage individuals living in more deprived areas to encourage early presentation and prompt treatment.

Cytomegalovirus-induced immunopathology and its clinical consequences

Human cytomegalovirus (CMV) is a ubiquitous DNA virus that causes severe disease in patients with immature or impaired immune systems. During active infection, CMV modulates host immunity, and CMV-infected patients often develop signs of immune dysfunction, such as immunosuppression and autoimmune phenomena. Furthermore, active viral infection has been observed in several autoimmune diseases, and case reports have linked primary CMV infection and the onset of autoimmune disorders. In addition, CMV infection promotes allograft rejection and graft-versus-host disease in solid organ and bone marrow transplant recipients, respectively, further implicating CMV in the genesis and maintenance of immunopathological phenomena. The mechanisms by which CMV could induce inhibition of host defense, inflammation, and autoimmunity are discussed, as is the treatment of virus-induced immunopathology with antivirals.

Diagnosing central nervous system vasculitis in children

PURPOSE OF REVIEW

To review the current literature of childhood central nervous system vasculitis, and to discuss a tailored approach to diagnosis and treatment based on recent evidence.

RECENT FINDINGS

Primary angiitis of the central nervous system in children (cPACNS) is an increasingly recognized inflammatory brain disease with potentially devastating neurological consequences. The diagnostic approach should be tailored to the clinical presentation of the child with suspected cPACNS and should address the expanding spectrum of inflammatory and noninflammatory brain diseases with overlapping clinical features. New evidence has confirmed that elective brain biopsies in children have a higher diagnostic yield than in adults and improve our ability to diagnose angiography-negative cPACNS. Finally, observational studies have shown that early diagnosis and aggressive treatment lead to improved neurological outcomes and lower mortality rates in patients with cPACNS.

SUMMARY

This review summarizes the recent data on diagnosis, classification, treatment, and outcomes in cPACNS. Our improved understanding of cPACNS facilitates a tailored diagnostic approach that results in earlier diagnosis and initiation of therapy for this potentially reversible condition.

Co-trimoxazole and prevention of relapses of PR3-ANCA positive vasculitis with pulmonary involvement

Background

Bacterial and viral respiratory tract infections may trigger relapses in patients with PR3-positive vasculitis. Data have suggested that treatment with co-trimoxazole may be beneficial, because this antibiotic could act by eliminating the offending microbe and thereby stopping the initiating stimulus.

Goal and methods

Prospective, randomized, placebocontrolled study of the efficacy of co-trimoxazole given 960 mg thrice weekly for 18 months in preventing relapses in patients with Wegener's granulomatosis (WG) in remission, after treatment with cyclophosphamide and prednisolone was conducted. Relapses and infections were assessed with predefined criteria based on clinical, laboratory, serological, microbiological, and histopathological findings. Sixteen patients were assigned to receive co-trimoxazole and 15 to receive placebo.

Results

Seventy five percent of the patients in the co-trimoxazole group remained in remission at 18 months and 55% of those in the placebo group. A proportional hazard regression analysis identified a positive PR3-ANCA test at the start of treatment, chronic nasal crusting, and Staphylococus aureus infection as risk factors for relapse. Furthermore, the analysis identified treatment with co-trimoxazole as an independent factor associated with prolonged diseasefree interval.

Conclusion

Treatment with co-trimoxazole reduces the incidence of relapses in patients with Wegener's granulomatosis in remission.

Risk factors and treatment outcomes of childhood stroke

Stroke is an important cause of childhood mortality and morbidity. The risk factors and pathophysiological processes of stroke in children are very different than those in adults. The range of risk factors is very wide, with over 100 presumptive risk factors described. There are a number of clinical guidelines, but despite recent increases in research, the evidence base underpinning these guidelines is sparse. Therefore, treatment is largely based upon expert consensus and extrapolation from adult data. Mortality from childhood stroke is relatively high and at least two-thirds of survivors have neurological impairments. Stroke can affect a wide range of neurocognitive domains and a high proportion of children require additional educational support and have a reduced quality of life.

[Septic vasculopathy]

Sepsis is one of the commonest causes of death around the world. The real frequency of cutaneous lesions in the setting of sepsis is unknown, but when they appear, they are usually one of the earliest signs of sepsis, thus allowing a rapid diagnosis of this potentially life-threatening condition. Four are the main physiopathologic mechanisms that can induce cutaneous lesions in sepsis: a) disseminated intravascular coagulation; b) direct vessel wall invasion by the microorganism; c) immune-mediated vasculitis, and d) septic embolism. We know that more than one of these mechanisms can appear in one single patient. In this review, we analyse these four mechanisms, their clinical presentation, and the histological findings that can be found in the cutaneous biopsy.

Large vessel vasculitis

Takayasu arteritis is a chronic granulomatous disease of the aorta and its major branches that usually affects women during the second and third decades of life, but it has been reported in young children. This review details the clinical, pathological and radiological features, differential diagnoses and management of the condition, focusing chiefly on the disease in children. The recent definition of Takayasu arteritis is discussed. The condition should be considered in patients with unexplained arterial hypertension or unexplained inflammatory syndromes without signs of localization. Since the disease may be life-threatening and progressive, early recognition is necessary to initiate appropriate therapy. Patients with persistent ischaemic symptoms including hypertension might benefit from revascularization procedures.

The infectious etiology of vasculitis

Infectious agents have been implicated in the etiopathogenesis of various vasculitides via numerous and overlapping mechanisms including direct microbial invasion of endothelial cells, immune complex mediated vessel wall damage and stimulation of autoreactive B and/or T cells through molecular mimicry and superantigens. While the causative role of hepatitis B virus in polyarteritis nodosa and hepatitis C virus in mixed cryoglobulinemia is clearly established, evidence for the association of other infectious agents with vasculitis, including human immunodeficiency virus, parvovirus B19, cytomegalovirus, varicella zoster virus, Staphylococcus aureus, rickettsiaceae, Treponema pallidum and Borrelia burgdorferi, among numerous others, is accumulating. The spectrum of association of infectious agents; bacteria, viruses and parasites, with systemic vasculitides, will be reviewed herewith.

Infectious serologies and autoantibodies in Wegener's granulomatosis and other vasculitides: novel associations disclosed using the Rad BioPlex 2200

In this study we assess the presence of antibodies against infectious agents as well as for a variety of autoantibodies in an attempt to establish associations between various vasculitides and infections in order to shed light on the etiopathogenesis of these diseases and perhaps implicate a potential cure. Sera from patients with Wegener's granulomatosis (WG), polyarteritis nodosa, microscopic polyangiitis, Churg Strauss, and giant cell arteritis were compared to healthy control sera. Serum samples were assessed, using the Bio-Rad BioPlex 2200, for the presence of Toxoplama gondii, cytomegalovirus (CMV), Epstein-Barr virus (EBV), Treponema pallidum, and Saccharomyces cerevisiae. Hepatitis B virus (HBV), hepatitis C virus (HCV), and anti-Helicobacter pylori antibodies were assessed by ELISA. In addition, sera were tested for a panel of antibodies associated with thrombophilia as well as various autoantibodies. The prevalence of antibodies toward HCV and H. pylori was significantly higher among patients with WG. IgG antibodies toward T. gondii and IgM antibodies toward CMV were significantly more common among WG patients than among controls. WG patients exhibited more antibodies toward EBV viral capsid antigen IgG and EBV early antigen IgG compared to sera from healthy controls. In WG, positive associations were disclosed between CMV IgG antibodies and the presence of gastrointestinal manifestations and renal involvement, and there was a higher Birmingham vasculitis activity score in association with elevated titers of EBV viral capsid antigen IgG antibodies. Otorhinolaryngeal manifestations were more common in those with positive IgG antibodies for EBV early antigen. Our results unveil novel associations between WG and various infectious agents, including HCV, H. pylori, T. gondii, CMV, and EBV. In addition to putative roles in initiation and exacerbation of the vasculitic process, it seems that these infectious agents also modulate the clinical phenotype of the disease.

Aortic aneurysm and orchitis due to Wegener's granulomatosis

We present a patient with Wegener's granulomatosis (WG) with involvement of the abdominal aorta, testis, peripheral nerve system, and skin. A 51-year-old man presented at our outpatient clinic with lower back pain. He had a history of smoking, hypertension, and an embryonal carcinoma of the left testis, treated 13 years ago with orchidectomy and chemotherapy. One month earlier, he underwent a partial orchidectomy of the right testis due to testicular swelling. Abdominal computed tomography showed a 3.8 cm wide aneurysm of the distal part of the aorta with inflammation. One week later he was admitted to the hospital with numbness of his hands and feet. Physical examination showed signs of peripheral microemboli. Serological laboratory tests revealed elevated antineutrophil cytoplasmic antibody titers with positive reactions against proteinase-3, indicating Wegener's disease. The chest X-ray was normal. Pathological examination of the right testis showed necrotizing vasculitis of a small artery. He was treated with cyclophosphamide and prednisolone. WG with extrapulmonary involvement occurs infrequently, and reports of manifestations of WG in aorta, testis, the peripheral nerve system, and skin are even more uncommon. Small- and medium-vessel vasculitis can precede large-vessel vasculitis or occur in the absence of small-vessel involvement. Therefore, WG should be included in the work-up of large-vessel vasculitis, which can give rise to periaortic inflammation.

Generalized Wegener's granulomatosis in an immunocompetent adult after cytomegalovirus mononucleosis and bacterial urinary tract infection

Human cytomegalovirus (HCMV) is frequently detected in autoimmune diseases, but its role in such disorders is poorly understood. Herein we describe the case of a young woman who developed generalized Wegener's granulomatosis (WG) after HCMV mononucleosis and urinary tract infection. During mononucleosis, the patient had extraordinarily high plasma levels of proinflammatory cytokines such as interleukin-5 and lymphotoxin alpha, autoantibodies, and a higher blood level of viral DNA than were found in other immunocompetent patients infected with HCMV or healthy controls. Active HCMV replication was detected after the onset of vasculitis, and HCMV genomes or antigens were found in blood, urine, and inflammatory lesions on the kidney. Thus, HCMV may have triggered or exacerbated inflammation and autoimmunity in this case of WG.