Inflammation, obesity, stress and coronary heart disease: is interleukin-6 the link?

There is mounting evidence that inflammation plays a role in the development of coronary heart disease (CHD). Observations have been made linking the presence of infections in the vessel wall with atherosclerosis, and epidemiological data also implicate infection in remote sites in the aetiology of CHD. In this article we propose a key role for the proinflammatory cytokine interleukin-6 (IL-6) in several mechanisms that contribute to the development of CHD. IL-6 is a powerful inducer of the hepatic acute phase response. Elevated concentrations of acute phase reactants, such as C-reactive protein (CRP), are found in patients with acute coronary syndromes, and predict future risk in apparently healthy subjects. The acute phase reaction is associated with elevated levels of fibrinogen, a strong risk factor for CHD, with autocrine and paracrine activation of monocytes by IL-6 in the vessel wall contributing to the deposition of fibrinogen. The acute phase response is associated with increased blood viscosity, platelet number and activity. Furthermore, raised serum amyloid A lowers HDL-cholesterol levels. IL-6 decreases lipoprotein lipase (LPL) activity and monomeric LPL levels in plasma, which increases macrophage uptake of lipids. In fatty streaks and in the atheromatous 'cap' and 'shoulder' regions, macrophage foam cells and smooth muscle cells (SMC) express IL-6, suggesting a role for this cytokine along with interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF-alpha), in the progression of atherosclerosis. Both these cytokines induce the release of IL-6 from several cell types, including SMC. During vascular injury SMC are exposed to platelets or their products, and cytokine production by SMC further contributes to vascular damage. Furthermore, circulating IL-6 stimulates the hypothalamic-pituitary-adrenal (HPA) axis, activation of which is associated with central obesity, hypertension and insulin resistance. Thus we propose a role for IL-6 in the pathogenesis of CHD through a combination of autocrine, paracrine and endocrine mechanisms. This hypothesis lends itself to testing using interventions to influence IL-6 secretion and actions.

Characteristics associated with hospitalisation for COVID-19 in people with rheumatic disease: data from the COVID-19 Global Rheumatology Alliance physician-reported registry

OBJECTIVES

COVID-19 outcomes in people with rheumatic diseases remain poorly understood. The aim was to examine demographic and clinical factors associated with COVID-19 hospitalisation status in people with rheumatic disease.

METHODS

Case series of individuals with rheumatic disease and COVID-19 from the COVID-19 Global Rheumatology Alliance registry: 24 March 2020 to 20 April 2020. Multivariable logistic regression was used to estimate ORs and 95% CIs of hospitalisation. Age, sex, smoking status, rheumatic disease diagnosis, comorbidities and rheumatic disease medications taken immediately prior to infection were analysed.

RESULTS

A total of 600 cases from 40 countries were included. Nearly half of the cases were hospitalised (277, 46%) and 55 (9%) died. In multivariable-adjusted models, prednisone dose ≥10 mg/day was associated with higher odds of hospitalisation (OR 2.05, 95% CI 1.06 to 3.96). Use of conventional disease-modifying antirheumatic drug (DMARD) alone or in combination with biologics/Janus Kinase inhibitors was not associated with hospitalisation (OR 1.23, 95% CI 0.70 to 2.17 and OR 0.74, 95% CI 0.37 to 1.46, respectively). Non-steroidal anti-inflammatory drug (NSAID) use was not associated with hospitalisation status (OR 0.64, 95% CI 0.39 to 1.06). Tumour necrosis factor inhibitor (anti-TNF) use was associated with a reduced odds of hospitalisation (OR 0.40, 95% CI 0.19 to 0.81), while no association with antimalarial use (OR 0.94, 95% CI 0.57 to 1.57) was observed.

CONCLUSIONS

We found that glucocorticoid exposure of ≥10 mg/day is associated with a higher odds of hospitalisation and anti-TNF with a decreased odds of hospitalisation in patients with rheumatic disease. Neither exposure to DMARDs nor NSAIDs were associated with increased odds of hospitalisation.

Diabetes mellitus: The linkage between oxidative stress, inflammation, hypercoagulability and vascular complications

BACKGROUND

Vascular complications are the leading cause of morbidity and mortality among patients with type 1 and type 2 diabetes mellitus. These vascular abnormalities result of a chronic hyperglycemic state, which leads to an increase in oxidative stress and inflammatory responses.

AIM

This review addresses the relationships among endothelial dysfunction, hypercoagulability and inflammation and their biomarkers in the development of vascular complications in type 1 and type 2 diabetes.

RESULTS

Inflammation, endothelial dysfunction, and hypercoagulability are correlated to each other, playing an important role in the development of vascular complications in diabetic patients. Moreover, it has been observed that several endothelial, inflammatory and pro-coagulant biomarkers, such as VWF, IL-6, TNF-α, D-dimer and PAI-1, are increased in diabetic patients who have microvascular and macrovascular complications, including nephropathy or cardiovascular disease.

CONCLUSION

It is promising the clinical and laboratory use of endothelial, inflammatory and pro-coagulant biomarkers for predicting the risk of cardiovascular and renal complications in diabetic patients and for monitoring these patients.

RAGE blockade stabilizes established atherosclerosis in diabetic apolipoprotein E-null mice

BACKGROUND

Previous studies suggested that blockade of RAGE in diabetic apolipoprotein (apo) E-null mice suppressed early acceleration of atherosclerosis. A critical test of the potential applicability of RAGE blockade to clinical settings was its ability to impact established vascular disease. In this study, we tested the hypothesis that RAGE contributed to lesion progression in established atherosclerosis in diabetic apoE-null mice.

METHODS AND RESULTS

Male apoE-null mice, age 6 weeks, were rendered diabetic with streptozotocin or treated with citrate buffer. At age 14 weeks, certain mice were killed or treated with once-daily murine soluble RAGE or albumin; all mice were killed at age 20 weeks. Compared with diabetic mice at age 14 weeks, albumin-treated animals displayed increased atherosclerotic lesion area and complexity. In diabetic mice treated with sRAGE from age 14 to 20 weeks, lesion area and complexity were significantly reduced and not statistically different from those observed in diabetic mice at age 14 weeks. In parallel, decreased parameters of inflammation and mononuclear phagocyte and smooth muscle cell activation were observed.

CONCLUSIONS

RAGE contributes not only to accelerated lesion formation in diabetic apoE-null mice but also to lesion progression. Blockade of RAGE may be a novel strategy to stabilize atherosclerosis and vascular inflammation in established diabetes.

Relapsing polychondritis. Survival and predictive role of early disease manifestations

To define the natural history of relapsing polychondritis, the probability of survival and causes of death were determined in 112 patients seen at one institution. By using covariate analysis, early clinical manifestations were identified that predicted mortality. The 5- and 10-year probabilities of survival after diagnosis were 74% and 55%, respectively. The most frequent causes of death were infection, systemic vasculitis, and malignancy. Only 10% of the deaths could be attributed to airway involvement by chondritis. Anemia at diagnosis was a marker for decreased survival in the entire group. There was an interaction between other disease variables and age in determining their impact on outcome. For patients less than 51 years old, saddle-nose deformity and systemic vasculitis were the worst prognostic signs. For older patients, only anemia predicted outcome. The need for corticosteroid therapy did not influence survival.

Pathogenesis of Crohn's disease: multifocal gastrointestinal infarction

In a prospective study, specimens of resected small and large intestine from fifteen patients with Crohn's disease were prepared by heparin-saline vascular perfusion, followed by either resin casting of the mesenteric vascular supply and tissue maceration or glutaraldehyde perfusion-fixation, resin casting, and tissue clearance. The specimens were examined by macrophotography, histopathology, and either scanning or transmission electronmicroscopy. A pathogenetic sequence of events in Crohn's disease was seen--vascular injury, focal arteritis, fibrin deposition, arterial occlusion mainly at the level of the muscularis propria, followed by tissue infarction or neovascularisation. These features were confined to segments of intestine affected by Crohn's disease and did not occur in normal bowel. The findings suggest that Crohn's disease is mediated by multifocal gastrointestinal infarction. This pathogenetic process is compatible with many of the clinical features of Crohn's disease, and its recognition has important implications for the identification of the primary cause of the illness and advances in clinical management.

Micronodular transformation (nodular regenerative hyperplasia) of the liver: a report of 64 cases among 2,500 autopsies and a new classification of benign hepatocellular nodules

Nodular regenerative hyperplasia is defined by hepatocellular nodules distributed throughout the liver in the absence of fibrous septa between the nodules. Most reports have been single cases so that the prevalence and clinical significance of nodular regenerative hyperplasia is uncertain. In this study, the hepatic histology of 2,500 consecutive autopsies was reviewed. A spectrum of nodular transformation was found with nodular regenerative hyperplasia present in 2.6% of autopsy livers and qualitatively similar but lesser degrees of nodular transformation in a further 10.2%. Nodular transformation was also seen in 47% of livers with cirrhosis and 69% with incomplete cirrhosis. Obliteration of many small portal veins was seen in all cases with nodular regenerative hyperplasia, but only 4.7% of these had evidence of portal hypertension. The prevalence of various clinical states was compared in nodular regenerative hyperplasia and in controls. The results confirm, extend and quantify the spectrum of associated diseases. Nodular regenerative hyperplasia occurs in 5.6% of individuals over age 80 and with increased frequency in patients with systemic arteritis, polymyalgia rheumatica, massive tumor infiltration and mineral oil deposition. Nodular regenerative hyperplasia appears to be the hepatic analogue of arterial and arteriolar nephrosclerosis. A new classification of nodular transformation is proposed that encompasses the spectrum of lesions described here and the previously defined entities of focal nodular hyperplasia, partial nodular transformation and "cirrhosis telangiectasia hepatis." The major conclusion is that nodular regenerative hyperplasia is a secondary and nonspecific tissue adaptation to heterogeneous distribution of blood flow and does not represent a specific entity.

Morphologic Findings of Coronary Atherosclerotic Plaques in Diabetics

OBJECTIVE

Coronary atherosclerotic plaque composition of diabetic subjects and localization of receptor for advanced glycation end products (RAGE) and its ligands have not been extensively studied.

METHODS AND RESULTS

Hearts from diabetic subjects and age, race, and sex-matched nondiabetic subjects dying suddenly were examined. Coronary arteries were dissected and lesions were evaluated for plaque burden, necrotic core size, and inflammatory infiltrate. The expression of RAGE, the RAGE-binding protein (S100-A12, EN-RAGE), and cell death (apoptosis) were also determined. Lesions from type II diabetic subjects had larger mean necrotic cores (P=0.01) and greater total and distal plaque load (P<0.001) than nondiabetic subjects. Necrotic core size correlated positively with diabetic status, independent of other risk factors. Intimal staining for macrophages, T-cells, and HLA-DR was also significantly greater in diabetic subjects (P=0.03, P=0.003, and P<0.0001), respectively. The association of increased macrophage infiltrate was independent of cholesterol levels and patient age. Expression of RAGE and EN-RAGE was significantly greater in diabetic subjects (P=0.004) and was associated with apoptotic smooth muscle cells and macrophages.

CONCLUSIONS

In sudden coronary death, inflammation and necrotic core size play a greater role in the progression of atherosclerosis in diabetic subjects. The expression of RAGE and EN-RAGE may further compromise cell survival and promote plaque destabilization.

Inflammation and atherosclerosis: novel insights into plaque formation and destabilization

BACKGROUND AND PURPOSE

The simplistic view of atherosclerosis as a disorder of pathological lipid deposition has been redefined by the more complex concept of an ongoing inflammatory response.

SUMMARY OF REVIEW

Apolipoprotein E and low-density lipoprotein (LDL)-receptor-deficient mice develop accelerated atherosclerosis allowing in-depth pathophysiological investigations. Atherosclerotic plaques in these mice contain large numbers of T cells and macrophages. Crossbreeding apolipoprotein E-deficient mice with T-cell-deficient mice and mice with impaired macrophage function (osteopetrotic op/op mice) disclosed the important impact of immune cells on atherosclerotic lesion development. In contrast to the detrimental role of T cells and macrophages, B cells appear to be atheroprotective. These basic experimental findings have partly been confirmed in studies of the human carotid artery system. Inflammation is not only instrumental in the development of human atheromatous plaques, but, importantly, plays a crucial role in the destabilization of internal carotid artery plaques, thus converting chronic atherosclerosis into an acute thrombo-embolic disorder. Humoral factors involved in internal carotid artery destabilization include cytokines, cyclooxygenase-2, matrix metalloproteinases, and tissue factor. Antibodies to oxidized LDL can reflect disease activity on one hand, but can also confer atheroprotection. Novel MRI techniques may aid in the in vivo assessment of acute plaque inflammation in humans.

CONCLUSIONS

The impact of inflammation on the development of atherosclerotic plaques and their destabilization opens new avenues for treatment. The effects of statins, acetylsalicyclic acid and angiotensin-converting enzyme inhibitors on stroke prevention may partly be attributable to their profound anti-inflammatory actions. Vaccination against modified LDL and heat shock proteins halt plaque progression in experimental atherosclerosis. Their potential for prevention of human atherosclerosis is currently under investigation.

Outcome of ANCA-associated renal vasculitis: a 5-year retrospective study

BACKGROUND

Renal involvement is frequently present in antineutrophil cytoplasmic autoantibody (ANCA)-associated systemic vasculitis and is an important cause of end-stage renal failure (ESRF).

METHODS

This retrospective, multicenter, sequential cohort study reports presenting features and outcome of 246 new patients diagnosed in London, UK, between 1995 and 2000.

RESULTS

Diagnostic subgroups were microscopic polyangiitis, 120 patients (49%); Wegener's granulomatosis (WG), 82 patients (33%); renal-limited vasculitis, 33 patients (13.5%); and Churg-Strauss angiitis, 11 patients (4.5%). Median age was 66 years, 57% were men, and median creatinine level at presentation was 3.87 mg/dL (342 micromol/L). ANCA was present in 92%. Cumulative patient survival at 1 and 5 years was 82% and 76%, respectively. Mortality was associated with age older than 60 years (P < 0.001), development of ESRF (P < 0.001), initial creatinine level greater than 2.26 mg/dL (200 micromol/L; P = 0.01), and sepsis (P < 0.048). ESRF occurred in 68 patients (28%), of whom 47% died. Fifty-six patients who presented with a creatinine level greater than 5.65 mg/dL (500 micromol/L) survived, and 31 patients (55%) achieved dialysis independence. Relapse occurred in 34% after a median of 13 months and was more common in patients with WG (P = 0.048) and proteinase 3-ANCA (P = 0.034). Leukopenia occurred in 41% and was associated with sepsis (P < 0.001).

CONCLUSION

Mortality and morbidity of ANCA-associated systemic vasculitis are improving compared with previous series, but remain high. Renal vasculitis often affects older patients, who have a particularly poor outcome. Early diagnosis improves outcome. Leukopenia, caused by immunosuppressive therapy, should be avoided because of the close association with sepsis and death.

Enhanced levels of soluble and membrane-bound CD40 ligand in patients with unstable angina. Possible reflection of T lymphocyte and platelet involvement in the pathogenesis of acute coronary syndromes

BACKGROUND

The CD40 ligand (CD40L) on activated T cells and platelets may be activating matrix metalloproteinases, inducing procoagulant activity, and be involved in the pathogenesis of acute coronary syndromes by promoting plaque rupture in atheroma.

METHODS AND RESULTS

To study the role of CD40L-CD40 interaction in coronary disease, we analyzed levels of soluble (s) and membrane-bound CD40L in the peripheral blood from 29 patients with stable angina, 26 with unstable angina, and 19 controls. Our main findings follow. (1) Patients with unstable angina had significantly raised serum levels of sCD40L when compared with patients with stable angina and controls. (2) Platelets could release large amounts of sCD40L when stimulated ex vivo with the thrombin receptor-agonist peptide SFLLRN in both patients and controls. (3) Platelets in patients with unstable angina were characterized ex vivo by decreased intracellular levels and decreased SFLLRN-stimulated release of sCD40L, which may possibly represent a higher percentage of degranulated platelets in these patients. (4) T cells in patients with unstable angina had enhanced surface expression of CD40L and increased release of sCD40L on anti-CD3/anti-CD28 stimulation in vitro when compared with patients with stable angina and controls. (5) Recombinant CD40L and serum from patients with unstable angina who had high sCD40L levels induced enhanced release of monocyte chemoattractant peptide-1 from mononuclear cells, a CC-chemokine involved in the pathogenesis of atherosclerosis.

CONCLUSIONS

This first demonstration of enhanced levels of soluble and membrane-bound forms of CD40L in angina patients, with particularly high levels in patients with unstable angina, suggests that CD40L-CD40 interaction may play a pathogenic role in both the long-term atherosclerotic process and in the triggering and propagation of acute coronary syndromes.

The hypercoagulable states

Patients are considered to have hypercoagulable states if they have laboratory abnormalities or clinical conditions that are associated with an increased risk of thrombosis (prethrombotic states) or if they have recurrent thrombosis without recognizable predisposing factors (thrombosis-prone). The number of specific primary hypercoagulable states that are recognized is growing. These disorders are generally inherited abnormalities of coagulation in which a physiologic anticoagulant mechanism is defective: for example, antithrombin III deficiency, protein C and protein S deficiency, abnormalities of the fibrinolytic system, and dysfibrinogenemias. Secondary hypercoagulable states are generally acquired disorders in patients with underlying systemic diseases or clinical conditions known to be associated with an increased risk of thrombosis: for example, malignancy, pregnancy, use of oral contraceptives, myeloproliferative disorders, hyperlipidemia, diabetes mellitus, and abnormalities of blood vessels and rheology. The complex pathophysiologic features of these secondary hypercoagulable states are discussed, and a framework is provided for the laboratory investigation and systematic clinical approach to the patient.

Antiinflammatory Effects of Angiotensin II Subtype 1 Receptor Blockade in Hypertensive Patients With Microinflammation

Background— Experimental studies revealed proinflammatory properties of angiotensin II. We evaluated antiinflammatory effects of the angiotensin II subtype 1 receptor antagonist olmesartan medoxomil alone and in cotherapy with the HMG-CoA reductase inhibitor pravastatin in patients with essential hypertension and microinflammation.

Methods and Results— We measured a panel of vascular inflammation markers, including high-sensitivity C-reactive protein, and lipid levels during 12 weeks of therapy with olmesartan (n=100) or placebo (n=99) in a prospective double-blind multicenter study. Pravastatin was added to the double-blind therapy at week 6 in both treatment arms. Blood pressure control was achieved with addition of hydrochlorothiazide. Olmesartan treatment had already significantly reduced serum levels of high-sensitivity C-reactive protein (−15.1%; P <0.05), high-sensitivity tumor necrosis factor-α (−8.9%; P <0.02), interleukin-6 (−14.0%; P <0.05), and monocyte chemotactic protein-1 (−6.5%; P <0.01) after 6 weeks of therapy, whereas placebo treatment (ie, blood pressure reduction) had no major effect on inflammation markers. After 12 weeks of therapy, high-sensitivity C-reactive protein (−21.1%; P <0.02), high-sensitivity tumor necrosis factor-α (−13.6%; P <0.01), and interleukin-6 (−18.0%; P <0.01) decreased further with olmesartan and pravastatin cotherapy, but treatment with pravastatin alone (ie, cotherapy with placebo) did not significantly alter inflammation markers. In contrast, addition of pravastatin led to a significant ( P <0.001) reduction in LDL cholesterol serum concentrations in the olmesartan and placebo treatment groups (−15.1% and −12.1%, respectively).

Conclusions— Angiotensin II receptor blockade significantly reduces vascular microinflammation in patients with essential hypertension by as early as week 6 of therapy. This antiinflammatory action of angiotensin II receptor antagonists may contribute to their beneficial cardiovascular effects.

Induction of remission by B lymphocyte depletion in eleven patients with refractory antineutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

To assess the clinical effects of rituximab therapy in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

METHODS

The study group comprised 11 patients who had active AAV despite receiving maximally tolerated doses of cyclophosphamide or had contraindications for cyclophosphamide use. All patients had ANCA reactive against proteinase 3. The patients received rituximab infusions and glucocorticoids to induce remission. Three patients also received plasma exchange. No other immunosuppressive agents were used. Glucocorticoids were tapered as soon as control of disease activity was achieved. Disease activity was monitored using the Birmingham Vasculitis Activity Score, modified for Wegener's granulomatosis.

RESULTS

Rituximab therapy was well tolerated by all patients, and adverse events were rare. Following the rituximab infusions, circulating B lymphocytes became undetectable, and ANCA titers decreased significantly. Remission was achieved in all patients and was maintained while B lymphocytes were absent.

CONCLUSION

The ability to achieve stable remissions with rituximab in patients with AAV refractory to conventional therapy suggests that B lymphocyte depletion may be a safe, effective, mechanism-based treatment modality for treatment of patients with these conditions.

Panniculitis. Part II. Mostly lobular panniculitis

The second part of our review of panniculitis summarizes the clinicopathologic features of the mostly lobular panniculitides. Erythema induratum of Bazin (nodular vasculitis) represents the most common variant of lobular panniculitis with vasculitis, although controversy persists about the nature of the involved vessels. Mostly lobular panniculitides without vasculitis comprise a series of disparate disorders. These include sclerosing panniculitis that results from chronic venous insufficiency of the lower extremities; panniculitis with calcification of the vessel walls such as calciphylaxis and oxalosis; and inflammatory diseases with crystals within the adipocytes such as sclerema neonatorum, subcutaneous fat necrosis of the newborn, and poststeroid panniculitis. Connective tissue diseases, such as systemic lupus erythematosus and dermatomyositis, pancreatic diseases, and alpha(1)-antitrypsin deficiency may also show a mostly lobular panniculitis with characteristic histopathologic features. Lobular panniculitis may also be an expression of infections, trauma, or factitial causes involving the subcutaneous fat. Lipoatrophy refers to a loss of subcutaneous fat due to a previous inflammatory process involving the subcutis, and it may be the late-stage lesion of several types of panniculitis. In contrast, lipodystrophy means an absence of subcutaneous fat with no evidence of inflammation and often the process is associated with endocrinologic, metabolic, or autoimmune diseases. Finally, cytophagic histiocytic panniculitis is the term that has been used to describe two different processes: one is inflammatory, a lobular panniculitis, and the other one is neoplastic, a subcutaneous T-cell lymphoma. The only common feature of these two different processes is the presence of cytophagocytosis in the lesions. (J Am Acad Dermatol 2001;45:325-61.)

LEARNING OBJECTIVE

At the completion of this learning activity, participants should be familiar with the pathogenesis, clinical manifestations, histopathologic findings, and treatment options for the most frequent variants of the lobular panniculitides.

Regulation of Superoxide Anion Production by NADPH Oxidase in Monocytes/Macrophages

Monocyte extravasation into the vessel wall has been shown to be a critical step in the development of atherosclerosis. Upon activation, monocytes produce a burst of superoxide anion due to activation of the NADPH oxidase enzyme complex. Monocyte-derived superoxide anion contributes to oxidant stress in inflammatory sites, is required for monocyte-mediated LDL oxidation, and alters basic cell functions such as adhesion and proliferation. We hypothesize that monocyte-derived superoxide anion production contributes to atherosclerotic lesion formation. In this brief review, we summarize our current understanding of the signal transduction pathways regulating NADPH oxidase activation and related superoxide anion production in activated human monocytes. Novel pathways are identified that may serve as future targets for therapeutic intervention in this pathogenic process. The contributions of superoxide anion and NADPH oxidase to atherogenesis are discussed. Future experiments are needed to clarify the exact role of NADPH oxidase-derived superoxide anion in atherogenesis, particularly that derived from monocytes.

HIV and autoimmunity

The association of immune dysfunction in patients with human immunodeficiency virus (HIV) infection and AIDS and the development of autoimmune diseases is intriguing. Yet, the spectrum of reported autoimmune phenomena in these patients is increasing. An infectious trigger for immune activation is one of the postulated mechanisms and derives from molecular mimicry. During frank loss of immunocompetence, autoimmune diseases that are predominantly T cell subtype CD8 driven predominate. There is evidence for B cell stimulation and many autoantibodies are reported in HIV patients. We propose a staging of autoimmune manifestations related to HIV/AIDS manifestations and the total CD4 count and viral load that may be beneficial in identifying the type of autoimmune disease and establishing the proper therapy. In stage I there is the acute HIV infection, and the immune system is intact. In this stage, autoimmune diseases may develop. Stage II describes the quiescent period without overt manifestations of AIDS. However, there is a declining CD4 count indicative of some immunosuppression. Autoimmune diseases are not found. During stage III there is immunosuppression with a low CD4 count and the development of AIDS. CD8 T cells predominant and diseases such as psoriasis and diffuse immune lymphocytic syndrome (similar to Sjogren's syndrome) may present or even be the initial manifestation of AIDS. Also during this stage no autoimmune diseases are found. In stage IV there is restoration of immune competence following highly active anti-retroviral therapy (HAART). In this setting, there is a resurgence of autoimmune diseases. The frequency of reported rheumatological syndromes in HIV-infected patients ranges from 1 to 60%. The list of reported autoimmune diseases in HIV/AIDS include systemic lupus erythematosus, anti-phospholipid syndrome, vasculitis, primary biliary cirrhosis, polymyosits, Graves' disease, and idiopathic thrombocytopenic purpura. Also, there is an array of autoantibodies reported in HIV/AIDS patients which include anti-cardiolipin, anti-beta2 GPI, anti-DNA, anti-small nuclear ribonucleoproteins (snRNP), anti-thyroglobulin, anti-thyroid peroxidase, anti-myosin, and anti-erythropoietin antibodies. The association of autoantibodies in HIV-infected patients to clinical autoimmune disease is yet to be established. With the upsurge of HAART, the incidence of autoimmune diseases in HIV-infected patients is increasing. In this review, we describe the various autoimmune diseases that develop in HIV/AIDS patients through possible mechanisms related to immune activation.

Presentation and outcome of gastrointestinal involvement in systemic necrotizing vasculitides: analysis of 62 patients with polyarteritis nodosa, microscopic polyangiitis, Wegener granulomatosis, Churg-Strauss syndrome, or rheumatoid arthritis-associated vasculitis

We reviewed the medical records of 62 patients with systemic small and medium-sized vessel vasculitides and gastrointestinal tract involvement followed at our institution between 1981 and 2002. This group included 46 men and 16 women (male:female ratio, 2.9), with a mean age of 48 +/- 18 years. Vasculitides were distributed as follows: 38 polyarteritis nodosa (21 related to hepatitis B virus), 11 Churg-Strauss syndrome, 6 Wegener granulomatosis, 4 microscopic polyangiitis, and 3 rheumatoid arthritis-associated vasculitis. Gastrointestinal manifestations were present at or occurred within 3 months of diagnosis in 50 (81%) patients and were mainly abdominal pain in 61 (97%), nausea or vomiting in 21 (34%), diarrhea in 17 (27%), hematochezia or melena in 10 (16%), and hematemesis in 4 (6%). Gastroduodenal ulcerations were detected endoscopically in 17 (27 %) patients, esophageal in 7 (11%), and colorectal in 6 (10%), but histologic signs of vasculitis were found in only 3 colon biopsies. Twenty-one (34%) patients had a surgical abdomen; 11 (18%) developed peritonitis, 9 (15%) had bowel perforations, 10 (16%) bowel ischemia/infarction, 4 (6%) intestinal occlusion, 6 (10%) acute appendicitis, 5 (8%) cholecystitis, and 3 (5%) acute pancreatitis. (Some patients had more than 1 condition.) Sixteen (26%) patients died.The respective 10-month and 5-year survival rates were 71% (95% confidence interval [CI], 52-90) and 56% (95% CI, 35-77) for the 21 surgical patients; and 94% (95% CI, 87-101) and 82% (95% CI, 70-94) for the 41 patients without surgical abdomen (p = 0.08). Peritonitis (hazard ratio [HR] = 4.3, p < 0.01), bowel perforations (HR = 5.7, p < 0.01), gastrointestinal ischemia or infarctions (HR = 4.1, p < 0.01), and intestinal occlusion (HR = 5.5, p < 0.01) were the only gastrointestinal manifestations significantly associated with increased mortality in multivariate analysis. For this subgroup of 15 patients, 6-month and 5-year survival rates were 60% (95% CI, 35-85) and 46% (95% CI, 19-73), respectively (p = 0.003). None of the other gastrointestinal or extraintestinal vasculitis-related symptoms, or angiographic abnormalities (seen in 67% of the 39 patients who underwent angiography), was predictive of surgical complications or poor outcome. However, prognosis has dramatically improved during the past 30 years, probably owing to better management of these more severely ill patients, with prompt surgical intervention when indicated, and the combined use of steroids and immunosuppressants.

Sjögren's syndrome: association of anti-Ro(SS-A) antibodies with vasculitis, hematologic abnormalities, and serologic hyperreactivity

The clinical significance of autoantibodies to Ro(SS-A) and La(SS-B) in Sjögren's syndrome was examined in a retrospective evaluation of 75 patients with symptoms of the sicca complex who had either primary Sjögren's syndrome or Sjögren's syndrome associated with another connective tissue disease. The clinical, hematologic, and serologic features associated with autoantibodies to the small molecular weight ribonucleoproteins Ro(SS-A) and La(SS-B) were ascertained. A striking clinical association of anti-Ro(SS-A) antibodies (found in 33 patients) with extraglandular disease (vasculitis, purpura, and lymphadenopathy) was seen. Hematologic abnormalities (anemia, leukopenia, and thrombocytopenia) were also associated with the presence of anti-Ro(SS-A) antibodies. Furthermore, anti-Ro(SS-A) antibody was associated with hyperglobulinemia, increased serologic reactivity in terms of rheumatoid and antinuclear factors, cryoglobulinemia, and hypocomplementemia. The presence of anti-Ro(SS-A) antibodies defines a subset of patients with Sjögren's syndrome who have systemic clinical manifestations including vasculitis, hematologic abnormalities, and serologic hyperreactivity.

Skin ulcers misdiagnosed as pyoderma gangrenosum

BACKGROUND

Pyoderma gangrenosum is a diagnosis of exclusion, and the misdiagnosis of pyoderma gangrenosum can result in substantial complications in patients who have other causes of severe cutaneous ulceration.

METHODS

We reviewed the charts of 240 patients with a diagnosis of pyoderma gangrenosum who were evaluated at our institution from 1975 through 2000, including 157 consecutive patients treated for presumed pyoderma gangrenosum from 1984 through 1992. We also reviewed the English-language literature.

RESULTS

Ninety-five patients (49 from our institution and 46 described in the literature) had skin ulcers with a clinical resemblance to pyoderma gangrenosum. The final diagnoses were vascular occlusive or venous disease, vasculitis, cancer, primary infection, drug-induced or exogenous tissue injury, and other inflammatory disorders. Of the 95 patients studied, 64 had been treated for pyoderma gangrenosum for a median of 10 months (range, 3 to 180). These 64 included 15 of the 157 consecutive patients treated for pyoderma gangrenosum at our institution (10 percent). Of the ulcers in the 64 patients treated for pyoderma gangrenosum, it was clear that those in 23 patients (36 percent) did not respond to treatment directed at pyoderma gangrenosum, those in 8 (12 percent) were exacerbated by such treatment, and those in 15 (23 percent) improved with such treatment.

CONCLUSIONS

The misdiagnosis of pyoderma gangrenosum is not uncommon and exposes patients to risks associated with its treatment. A thorough evaluation is required in all patients suspected of having pyoderma gangrenosum in order to rule out alternative diagnoses.

Neurological complications of vasculitis

The vasculitides are a group of disorders that include the polyarteritis nodosa group of systemic necrotizing vasculitides, hypersensitivity vasculitis, Wegener's granulomatosis, lymphomatoid granulomatosis, giant cell arteritis, Behçet's disease, and isolated angiitis of the central nervous system. Classification is based on clinical, angiographic, and histological features. The frequency and distribution of neurological involvement vary with the underlying disorder and may provide the initial symptoms. Polyarteritis nodosa and Wegener's granulomatosis may affect both the central and peripheral nervous systems, whereas isolated angiitis of the central nervous system and Behçet's disease affect the central nervous system alone. Neurological dysfunction occurs in 80% of patients with polyarteritis nodosa and fewer than 10% of patients with hypersensitivity vasculitis. The mechanism of neurological dysfunction in the vasculitides is tissue ischemia. The clinical effects of ischemia vary, and symptoms may be transient or prolonged. Mononeuritis multiplex, polyneuropathy, and stroke are frequent complications, but encephalopathies, cranial neuropathies, and brachial plexopathies are seen as well. The occurrence of symptoms late in the course of a disease suggests ischemia resulting from healed, scarred vessels as well as from those that are acutely inflamed; this is the case in Takayasu's arteritis and possibly also in polyarteritis nodosa. Treatment is based on identifying and removing the sensitizing agent when possible. Wegener's granulomatosis requires therapy with cyclophosphamide; temporal arteritis, with corticosteroids. In other vasculitides a balance must be reached between the progression of the disease and the side effects of immunosuppression.

Nonsystemic vasculitic neuropathy

Among 65 patients with necrotizing vasculitis, 45 had systemic and 20 had nonsystemic vasculitic neuropathy. In nonsystemic vasculitic neuropathy, clinically only nerves are affected; there are no, or few, constitutional symptoms or serological abnormalities. The clinical and pathological features are those of an ischaemic neuropathy caused by a necrotizing vasculitis of small arterioles. These 20 patients had neuropathic symptoms for a median time of 11.5 yrs (range 1-35 yrs). The clinical pattern of neuropathy was that of multiple mononeuropathy in 13, asymmetric neuropathy in 4, distal polyneuropathy in 3, and sensory polyneuropathy in 1. As compared with their initial evaluation, 8 are now worse, 5 are better, 4 are approximately the same, and 3 are dead from unrelated causes. Prednisone was thought to prevent the development of new lesions in some cases. By contrast, of the 41 patients with systemic necrotizing vasculitis whose outcome is known, 12 are dead (median time, 1.5 yrs, range 3 months-8 yrs) and 29 are alive (median time, 6 yrs, range 6 months-22 yrs).

CT and MR imaging findings of bowel ischemia from various primary causes

Ischemic bowel disease represents a broad spectrum of diseases with various clinical and radiologic manifestations, which range from localized transient ischemia to catastrophic necrosis of the gastrointestinal tract. The primary causes of insufficient blood flow to the intestine are diverse and include thromboembolism, nonocclusive causes, bowel obstruction, neoplasms, vasculitis, abdominal inflammatory conditions, trauma, chemotherapy, radiation, and corrosive injury. Computed tomography (CT) or magnetic resonance (MR) imaging can demonstrate the ischemic bowel segment and may be helpful in determining the primary cause. The CT and MR imaging findings include bowel wall thickening with or without the target sign, intramural pneumatosis, mesenteric or portal venous gas, and mesenteric arterial or venous thromboembolism. Other CT findings include engorgement of mesenteric veins and mesenteric edema, lack of bowel wall enhancement, increased enhancement of the thickened bowel wall, bowel obstruction, and infarction of other abdominal organs. However, regardless of the primary cause, the imaging findings of bowel ischemia are similar. Furthermore, the bowel changes simulate inflammatory or neoplastic conditions. Understanding the pathogenesis of various conditions leading to mesenteric ischemia helps the radiologist recognize ischemic bowel disease and avoid delayed diagnosis, unnecessary surgery, or less than optimal management.

Urticarial vasculitis: a histopathologic and clinical review of 72 cases

BACKGROUND

Urticarial vasculitis is a subset of vasculitis characterized clinically by urticarial skin lesions and histologically by necrotizing vasculitis.

OBJECTIVE

A review of patients with urticarial vasculitis was undertaken to further characterize the clinical and histologic findings and to differentiate this disorder from urticaria and other types of cutaneous vasculitis.

METHODS

Seventy-two cases of biopsy-proven urticarial vasculitis were selected for a review of medical records, laboratory data, and histologic findings. Fifty cases of simple urticaria were also reviewed for purposes of comparison.

RESULTS

Systemic symptoms in patients with urticarial vasculitis included angioedema in 30 patients (42%), arthralgias in 35 (49%), pulmonary disease in 15 (21%), and abdominal pain in 12 (17%). Twenty-three patients (32%) had hypocomplementemia. Forty-six of 72 patients (64%) had lesions that lasted more than 24 hours, 23 of 72 (32%) had painful or burning lesions, and 25 of 72 (35%) had lesions that resolved with purpura. Sixteen biopsy specimens from the 23 patients with hypocomplementemia showed dermal neutrophilia in addition to the perivascular infiltrate. Of the 23 patients with hypocomplementemia, 20 (87%) had fluorescence of the blood vessels and 16 (70%) had fluorescence of the basement membrane zone as determined by routine direct immunofluorescence.

CONCLUSION

Patients with hypocomplementemia were more likely to have systemic symptoms such as urticaria that resolved with purpura, arthralgias, abdominal pain, and chronic obstructive pulmonary disease. The histologic pattern associated with hypocomplementemia is interstitial neutrophilic infiltrate of the dermis and an immunofluorescent pattern of immunoglobulins or C3 in the blood vessels and along the basement membrane zone.

Relapse rate, renal survival, and cancer morbidity in patients with Wegener's granulomatosis or microscopic polyangiitis with renal involvement

Wegener's granulomatosis (WG) and microscopic polyangiitis (MPA) are both frequently associated with antineutrophil cytoplasmic autoantibodies (ANCA). Immunosuppressive treatment has dramatically improved outcome for these patients, but today we have to deal with the problems of relapses, cases refractory to treatment, and long-term side effects of therapy. This study comprises a consecutive series of 123 patients with WG (n=56) or MPA (n=67) with biopsy-confirmed renal involvement, followed up for a median of 55 mo (range, 0.1 to 273.2 mo). ANCA was detected by enzyme-linked immunosorbent assay in 97% of patients. Nearly half of the patients (46%) relapsed. There was no statistically significant difference in overall relapse rate according to type of ANCA. Renal survival was 78% in patients alive at the end of follow-up. Three variables seemed important for renal survival: serum creatinine, the titer of proteinase 3-ANCA measured by capture enzyme-linked immunosorbent assay, and B thrombocyte count, at time of referral. Cancer incidence data were obtained from the population-based South Swedish Regional Tumor Registry. Standardized morbidity ratio was calculated using expected values from the health care region. We found an 11-fold increase in risk for bladder cancer in patients treated with cyclophosphamide for at least 12 mo. Skin carcinoma had the strongest relationship with azathioprine use for at least 12 mo and with corticosteroid therapy for at least 48 mo. In addition, four patients developed myelodysplastic syndrome and five had carcinoma in situ of the skin. Because the therapeutic regimen used today is not efficient enough to prevent relapses and is associated with a host of side effects, of which the risk for cancer is by far the most important, improved therapy and medical care are needed for patients with WG and MPA.