Epidemiology of the vasculitides

The Clinical Significance of Small Vessel Vasculitis on Temporal Artery Biopsies

BACKGROUND

Giant cell arteritis (GCA) is the most common type of systemic vasculitis in the elderly. Untreated, it can lead to irreversible blindness. Its diagnosis relies on a temporal artery biopsy (TAB). However, a proportion of patients have small vessel vasculitis (SVV) on biopsy; the prognosis of which remains unclear. The aim of this study is to compare the clinical presentation and long-term outcomes of those with SVV with negative and positive biopsies to determine whether long-term corticosteroid therapy can be avoided in these patients.

METHODS

Post hoc analysis of patients with suspected GCA who underwent TAB and fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) scan as part of a prospective GCA and PET cohort. Patients were divided in to 3 groups based on TAB result: positive (inflammation in the main artery wall), negative (no inflammation), and SVV (isolated vasa vasorum or periadventitial SVV). Clinical, serological, and PET/CT data of patients with SVV were compared with those with positive and those with negative biopsies.

RESULTS

For the 58 eligible patients recruited between May 2016 and December 2017, 11 had SVV, 12 had positive, and 35 had negative biopsies. Patients with SVV had similar clinical, serological, and PET/CT findings to those with negative biopsies. Compared with those with positive biopsies, patients with SVV had lower erythrocyte sedimentation rate (25 vs 78 mm/hour; P = 0.02), platelet count (296 vs 385 ×109/L; P = 0.03), and a lower median total vascular score on PET/CT scan (1.0 vs 13.5; P = 0.01). Median prednisone dose was lower (4.8 vs 11.7 mg; P = 0.015) and fewer were on steroid-sparing agents (20% vs 67%; P = 0.043) at 6 months. The percentage of patients with a clinical diagnosis of GCA was similar between those with SVV (3/11, 27.3%) and those with negative biopsies (5/35, 14.3%; P = 0.374).

CONCLUSIONS

Patients with SVV on TAB had similar clinical features, PET/CT findings, and 6-month outcomes to those with negative biopsies. Small vessel vasculitis can be treated as equivalent to a negative biopsy when being considered for diagnosis and treatment of GCA.

Comprehensive Analysis of Sex Differences at Disease Manifestation in ANCA-Associated Glomerulonephritis

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a small vessel vasculitis affecting multiple organ systems, including the kidney. Besides investigations focusing on renal outcomes, sex differences associated with distinct clinical and histopathological findings in ANCA glomerulonephritis (GN) have not been systematically investigated. Therefore, we here aimed to systematically analyze sex differences in patients with AAV and biopsy-proven ANCA GN. We provide a comprehensive analysis of 53 kidney biopsies with ANCA GN retrospectively included between 2015 and 2020 and identified specific sex differences in ANCA GN concerning laboratory parameters and systematic scoring of renal histopathology glomerular and tubulointerstitial lesions, and extrarenal manifestations of AAV. We did not observe any correlation between sex and short-term clinical AAV course or disease severity by comparing general AAV parameters. AAV manifestations in females occurred at an older age with more joint involvement. Regarding histopathological findings, we, again, observed no sex difference among ANCA GN classification, but a significant correlation between females and distinct histopathological findings with less tubulointerstitial inflammation and vasculitis of peritubular capillaries. Finally, we here identified fewer associations between clusters of clinical, laboratory parameters, and histopathological findings in females as compared to males. These findings are of great relevance and further improve our understanding of sex differences in the pathogenesis of ANCA GN. While future studies about specific sex differences and conclusions in these clusters are crucial, our observations further support that sex differences are relevant, affect distinct parameters, and influence clinical, laboratory parameters, and histopathological findings in AAV, particularly ANCA GN.

Epidemiologic Features of Systemic Vasculitides in the Southeast Region of Brazil: Hospital-Based Survey

BACKGROUND/OBJECTIVE

The epidemiology of vasculitis is variable in different geographic areas, and this issue has not been approached in Brazil yet. The objective of this study was to assess the frequency of vasculitis in specialized centers in Brazil.

METHODS

This cross-sectional study was performed in 9 vasculitis outpatient clinics from 6 different states mainly from the Southeast and the Northeast regions of Brazil between 2015 and 2017. Diagnosis and/or classification criteria for Behçet disease (BD), Takayasu arteritis (TA), giant cell arteritis (GCA), polyarteritis nodosa (PAN), granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA), and cryoglobulinemic vasculitis (CryoVas) were used to include patients with at least 6 months of follow-up in this hospital-based survey.

RESULTS

A total of 1233 patients with systemic vasculitis were included from the Southeast region. Behçet disease was the most frequent vasculitis (35.0%) followed by TA (26.4%), GPA (16.2%), PAN (5.8%), GCA (5.8%), EGPA (4.3%), MPA (3.4%), and CryoVas (3.0%). Up to 7.8% of vasculitis patients had a juvenile onset, and the frequency of vasculitides found in children and adolescents was as follows: TA (52.6%), BD (24.7%), GPA (12.4%), and PAN (10.3%). No cases of EGPA, MPA, and CryoVas were diagnosed before the age of 18 years. As a comparator, 103 vasculitis patients were included in the Northeast of Brazil where TA was found in 36.9% and BD in 31.1% of vasculitis cases. No GCA cases were found in the Northeast part of Brazil.

CONCLUSIONS

Similar to the epidemiology of vasculitis in Asia, BD and TA are the most frequent vasculitis in Southeastern Brazilian referral centers.

Consideration of Therapeutic Plasma Exchange in Association With Inflammatory Lesions in ANCA-Associated Glomerulonephritis: A Real-World Retrospective Study From a Single Center

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a systemic vasculitis, most frequently presenting as microscopic polyangiitis (MPA) or granulomatosis with polyangiitis (GPA). Pathogenic ANCAs trigger a deleterious immune response resulting in pauci-immune necrotizing and crescentic glomerulonephritis (GN). Standard therapeutical regimens include aggressive immunosuppressive therapy. Since some patients require renal replacement therapy (RRT) despite intensive immunosuppressive therapy, additional therapeutic plasma exchange (PEX) to deplete pathogenic ANCAs has been recommended but its value has recently been questioned. Because therapeutic decision making is crucial in these critically ill patients, we here aimed to identify inflammatory lesions in association with PEX consideration in a retrospective study from a single center tertiary hospital in a real-world population of 46 patients with severe AAV requiring intensive care treatment. The decision to consider PEX was more likely in patients with need for intensive care treatment and severe renal dysfunction. In contrast, short-term outcomes did not depend on clinical, or laboratory characteristics assessed at admission. Histopathological analysis confirmed active disease reflected by increased glomerular necrosis and crescents, but these histopathological findings did not associate with short-term outcome either. Interestingly, only increased global glomerular sclerosis in renal biopsies associated with a detrimental short-term outcome. In conclusion, our study investigated determinants for the consideration of therapeutic PEX in patients with severe AAV requiring intensive care treatment. This aspect underscores the need for renal biopsy and requires further investigation in a prospective controlled setting for therapeutic decision making especially in patients with severe AAV requiring intensive care treatment, especially important for treating intensivists.

Histopathological Findings Predict Renal Recovery in Severe ANCA-Associated Vasculitis Requiring Intensive Care Treatment

Renal involvement is a common and severe complication of AAV as it can cause ESRD. Histopathological subgrouping and ARRS are helpful to predict long-term ESRD in patients with AAV. Because a subgroup of critically ill patients with severe AAV present with deterioration of kidney function requiring RRT at admission, we here aimed to evaluate histopathological findings and predictive value of Berden's histopathological subgrouping and ARRS for severity of AKI and requirement of RRT during the short-term clinical course in critically ill patients requiring intensive care treatment and predictors for short-term renal recovery in patients requiring RRT. A subgroup of 15/46 (32. 6%) AAV patients with biopsy-proven AAV required RRT during the short-term course of disease, associated with requirement of critical care treatment. While histopathological subgrouping and ARRS were associated with requirement of acute RRT, presence of global glomerular scarring was the strongest predictor of failure to recover from RRT after initiation of remission induction therapy. This new aspect requires further investigation in a prospective controlled setting for therapeutic decision making especially in this subgroup.

Childhood-onset severe hypereosinophilic asthma: efficacy of benralizumab

Hypereosinophilic syndrome (HES) is a group of rare chronic disorders that are defined by an absolute blood eosinophil count (BEC) of at least 1.500×10⁹cells·L⁻¹ on at least two occasions [1] with absence of secondary causes of eosinophilia (including parasitic infections, malignancy as myeloproliferative variants) and end-organ eosinophilic infiltration with associated damage [2]. In 2006, a working group modified the definition of HES to include other previously distinct disease entities associated with eosinophilia, such as eosinophilic granulomatosis with polyangiitis (EGPA, formerly known as Churg–Strauss syndrome) and chronic eosinophilic pneumonia [3]. EGPA typically occurs in middle-aged adults with asthma, and childhood-onset is rare with a prevalence of 10–13 patients per million people [4, 5]. We report here a series of six children with childhood-onset asthma with oral corticosteroid (OCS) dependence associated with hypereosinophilic asthma with a long-term follow-up and the marked efficacy of benralizumab. The study was declared to the French Data Protection Authority (CNIL) according to the reference methodology MR004. All of the included patients or their parents received an information note and were given the opportunity to oppose the use of their personal data, but no refusals were received.

Severe hypereosinophilic asthma in children is extremely rare. This letter adds to the existing literature by providing long-term follow-up, and is the first report of the marked efficacy of benralizumab after failure of other biologic treatments.https://bit.ly/2G7Tc2k

Prognostic Factors in Anti-Neutrophil Cytoplasmic Antibody-Associated Glomerulonephritis with Severe Glomerular Sclerosis: A National Registry-Based Cohort Study

Background

Classification of patients with anti-neutrophil cytoplasmic antibody-associated glomerulonephritis (ANCA-GN) into histological classes is useful for predicting a patient's risk of progression to end-stage renal disease (ESRD). However, even in the worst prognostic group, the 5-year end-stage renal disease-free survival rate is as high as 50%.

Objectives

To investigate those prognostic factors indicative of progression to ESRD in patients with ANCA-GN and sclerosing histology.

Methods

Patients from the Norwegian Kidney Biopsy Registry between 1991 and 2012 who had biopsy verified pauci-immune glomerulonephritis, positive ANCA serology, and sclerosing histology were included. Cases with ESRD during follow-up were identified via linkage with the Norwegian Renal Registry. Potential prognostic factors with relevant cut-offs were compared in patients with and without progression to ESRD during follow-up.

Results

Of 23 included patients, 10 progressed to ESRD. ESRD patients had a lower initial estimated glomerular filtration rate (eGFR; 21 versus 52 ml/min/1.73 m²) and a lower percentage of normal glomeruli (4% versus 15%). Five-year risks of ESRD with eGFR >15 versus ≤15 ml/min/1.73 m² were 77% and 15%, with percentage normal glomeruli >10% versus ≤10%, 83% and 39%.

Conclusions

eGFR and percentage of normal glomeruli are strong risk factors for ESRD in ANCA-GN with sclerosing histology.

Prognosis and Histological Classification in Elderly Patients with ANCA-Glomerulonephritis: A Registry-Based Cohort Study

Background

The value of a histologic classification scheme to classify patients with anti-neutrophil cytoplasmic antibody-associated glomerulonephritis (ANCA-GN) into focal, mixed, crescentic, and sclerotic types for predicting risk of end-stage renal disease (ESRD) is well documented. However, the prognostic value of histological classification specifically in elderly patients (≥70 years) with ANCA-GN has not previously been investigated.

Methods

Patients with biopsy-verified pauci-immune necrotizing glomerulonephritis were identified from the Norwegian Kidney Biopsy Registry between 1991 and 2012 and those ≥70 years of age at the time of diagnosis and having positive anti-neutrophil cytoplasmic antibody serology were included in this study. The incidence rate of ESRD and/or death was determined by linking the study cohort to the Norwegian Renal Registry and the Population Registry of Norway. The ESRD-free survival and patient survival were compared between the 4 histological types.

Results

Of the 81 patients included, 20 progressed to ESRD and 34 died. The 1-year and 5-year ESRD-free survival varied between histological groups (p = 0.003) as follows: focal, 97% and 97%, respectively; mixed, 70% and 57%; crescentic, 76% and 63%; and sclerotic, 49% and 49%. Patient survival did not differ significantly between groups (p = 0.30).

Conclusion

Histological classification in elderly patients with ANCA-GN is useful for predicting ESRD but not survival.

Eosinophilic granulomatosis with polyangiitis in childhood: retrospective experience from a tertiary referral centre in the UK

OBJECTIVE

To describe the presenting clinical features, treatment and outcome in children with eosinophilic granulomatosis with polyangiitis (EGPA) and to define factors that predicted mortality.

METHODS

A retrospective case notes review of patients fulfilling the Chapel Hill Consensus Conference definition and/or ACR criteria for EGPA seen at Great Ormond Street Hospital, London. Demographics, clinical features, histopathology, treatment and outcomes were recorded. Descriptive statistics were expressed as median and range. Fisher's exact test was used for group comparisons. The Paediatric Vasculitis Activity Score and Paediatric Vasculitis Damage Index (PVDI) were calculated.

RESULTS

Thirteen children (38% female) aged at diagnosis 14.1 (4-15.6) years were identified. The median time to diagnosis was 2 (0-7.3) years. History of asthma was documented in 76%. The most common presenting features were pulmonary (69%), skin (61%), gastrointestinal (46%), cardiac involvement (46%), paranasal sinus abnormality (38%), arthritis/arthralgia (38%) and neurological involvement (15%). Paediatric Vasculitis Activity Score at presentation was 8/63 (2-25/63); ANCA was negative in all 10/13 patients tested. Treatment included corticosteroids in all, combined with CYC in 38% or AZA in 23%. PVDI at 12 (3-48) months follow-up was 3/72 (0-13/72). Relapses were recorded in 46%. Mortality was 15%; cardiomyopathy and PVDI scores ⩾5 significantly associated with mortality risk (P = 0.012).

CONCLUSION

EGPA in the paediatric population is a rare and potentially life-threatening vasculitis. Increased awareness is essential to secure a timely diagnosis and to promptly initiate treatment since our data emphasize a high mortality, particularly in those with cardiac involvement and significant accrued damage.

PTPN22 R620W polymorphism and ANCA disease risk in white populations: a metaanalysis

OBJECTIVE

No clear consensus has been reached on the PTPN22 R620W polymorphism and anti-neutrophil cytoplasmic antibody (ANCA) disease, especially when stratified by ANCA specificity and disease phenotypes.

METHODS

A metaanalysis was conducted on the PTPN22 R620W polymorphism across 4 studies in 1399 white patients with ANCA disease and 9934 normal control subjects.

RESULTS

Overall, metaanalysis showed a statistically significant association between the A allele and ANCA disease in all subjects (OR 1.44, 95% CI 1.26-1.64, p < 0.00001), and stratification by disease category indicated the A allele was associated with granulomatosis with polyangiitis (Wegener's; GPA; OR 1.72, 95% CI 1.35-2.20, p < 0.0001) and microscopic polyangiitis (MPA; OR 1.53, 95% CI 1.08-2.15, p = 0.02) as compared to controls. However, when stratified by ANCA specificity, the association of the A allele was statistically evident among those with proteinase 3 (PR3) ANCA disease (OR 1.74, 95% CI 1.25-2.430, p = 0.001), with the same trend but not statistically associated with myeloperoxidase ANCA disease (OR 1.94, 95% CI 0.64-5.85, p = 0.24). The marked associations were also demonstrated between this allele with lung (OR 1.69, 95% CI 1.21-2.36, p = 0.002), ENT (OR 2.03, 95% CI 1.45-2.84, p < 0.0001), skin (OR 2.55, 95% CI 1.69-3.84, p < 0.0001), and peripheral neuropathy involvement (OR 2.12, 95% CI 1.39-3.22, p = 0.0005).

CONCLUSION

The PTPN22 620W allele confers susceptibility to the occurrence and development of ANCA disease in whites, with specific evidence among subsets with GPA, MPA, and PR3 ANCA.

Long-term outcome of anti-neutrophil cytoplasm antibody-associated glomerulonephritis: evaluation of the international histological classification and other prognostic factors

BACKGROUND

Anti-neutrophil cytoplasm antibody (ANCA) associated vasculitis with renal involvement requires treatment with potentially toxic drugs to reduce morbidity and mortality, and there is a major challenge to determine clinical and histological features predictive of renal prognosis. The aim of our study was to evaluate the use of the 2010 international histological classification for ANCA-associated glomerulonephritis (AAGN) as a predictor of renal outcome when used in conjunction with other prognostic factors.

METHODS

One hundred and four patients with AAGN treated at our centre were included: 23 were classified as focal, 26 as crescentic, 48 as mixed and 7 as sclerotic. Renal outcomes were based on estimated glomerular filtration rate (eGFR) at 1 and 5 years, and on renal survival.

RESULTS

By univariate analysis, patients in the focal class had the best renal outcome, those in the sclerotic class the worst outcome, and those in the mixed and crescentic classes had intermediate renal survival. There was no significant difference in outcome between the mixed and crescentic classes. In multivariate models, histological class did not improve model fit or associate with renal outcome after adjusting for established prognostic factors. Lower percentage of normal glomeruli, greater degree of tubular atrophy (TA), MPO-ANCA positivity, increasing age and lower starting eGFR, all correlated with poorer renal outcomes.

CONCLUSIONS

We conclude that, in our cohort of patients, the international histological classification is predictive of renal outcome in AAGN, but did not appear to be additionally informative over other established prognostic factors in multivariate analysis. However, it may be of value to combine the current histological classification with other established parameters, such as TA and percentage normal glomeruli.

Predictors of treatment resistance and relapse in Chinese patients with antineutrophil cytoplasmic antibody-associated disease

OBJECTIVE

The prevalence and significance of treatment resistance and relapse in patients from China with antineutrophil cytoplasmic antibody-associated (ANCA) disease are poorly understood.

METHODS

A total of 98 patients with ANCA vasculitis, diagnosed between January 2003 and December 2009 in the China-Japan Friendship Hospital, were enrolled in this retrospective study.

RESULTS

Fifteen patients (15.3%) were categorized as having cytoplasmic and/or proteinase 3 (PR3) ANCA and 83 patients (84.7%) had perinuclear and/or myeloperoxidase (MPO) ANCA. After the induction phase treatment, the disease was resistant to therapy in 24 (25%) of the patients. A response to initial treatment occurred in 74 patients (75%). Of these 74 patients, remission was achieved and sustained with or without maintenance therapy in 41 patients (55%). Multivariable logistic regression models revealed that female sex was a statistically significant predictor of treatment resistance (OR 2.85; 95% CI: 1.06-2.86; p = 0.036). Additionally, elevated serum creatinine level, with each increment of 150 μmol/l, predicted resistance (p = 0.002). Among the 74 patients where remission was achieved, Cox proportional hazards models detected that those with PR3 ANCA were 1.31 times more likely to experience a relapse than were patients with MPO ANCA (95% CI: 1.01-5.35; p = 0.0001). Lung involvement was associated with an increased risk of relapse (HR 1.87; 95% CI: 1.12-4.35; p = 0.014). Although not significant, advanced age tended to be associated with relapse (p = 0.08).

CONCLUSION

Our findings highlight the important effect of female sex and severity of renal disease at presentation as predictors of treatment resistance, and PR3 ANCA and lung involvement as predictors of relapse.

Childhood-onset eosinophilic granulomatosis with polyangiitis (formerly Churg-Strauss syndrome): a contemporary single-center cohort

OBJECTIVE

To date only 38 cases of childhood-onset eosinophilic granulomatosis with polyangiitis (cEGPA; formerly Churg-Strauss syndrome) have been reported. Additional patients with cEGPA could enhance the understanding of this rare and life-threatening condition. Our objectives were (1) to determine the frequency of specific organ system involvement; (2) to examine initial therapeutic regimen; and (3) to document disease and therapy-related morbidity in a contemporary cohort of patients with cEGPA.

METHODS

Retrospective review of patients evaluated at the Cleveland Clinic between 2003 and 2011 who met either American College of Rheumatology or Lanham criteria for EGPA and whose age was < 18 years at symptom onset.

RESULTS

Nine patients (8 female; 7 white) were identified. Median age at onset of rhinitis/asthma symptom was 13 years and median age at diagnosis of cEGPA was 15 years. All patients demonstrated eosinophilia, upper airway disease (allergic rhinitis, chronic sinusitis, and/or nasal polyps), and pulmonary involvement. Other frequently involved organ systems included musculoskeletal (67%), gastrointestinal (67%), cutaneous (67%), neurologic (56%), and cardiac (44%). Antineutrophil cytoplasmic antibody (ANCA) serologies were negative in all patients. The medications used most frequently for initial therapy included oral (44%) or intravenous corticosteroids (56%) and azathioprine (67%). Disease or therapeutic complications occurred in half of the cohort and included heart failure, stroke, and sequela from longterm, high-dose steroids.

CONCLUSION

Eosinophilia, in combination with upper airway, pulmonary, musculoskeletal, neurologic, and cardiac manifestations, is frequently observed in cEGPA. ANCA titers are often negative. Steroids are the mainstay of initial therapy but steroid-related side effects occur regularly.

Antineutrophil cytoplasmic antibodies testing in a large cohort of unselected greek patients

Objective. To retrospectively evaluate ANCA testing in a cohort of unselected Greek in- and outpatients. Methods. In 10803 consecutive serum samples, ANCA were tested by indirect immunofluorescence (IIF) and ELISA. ELISA in inpatients was performed only on IIF positive sera. Results. Low prevalence (6.0%) of IIF positive samples was observed. Among these samples, 63.5% presented perinuclear (p-ANCA), 9.3% cytoplasmic (c-ANCA) and 27.2% atypical (x-ANCA) pattern. 16.1% of p-ANCA were antimyeloperoxidase (anti-MPO) positive, whereas 68.3% of c-ANCA were antiproteinase-3 (anti-PR3) positive. Only 17 IIF negative outpatients' samples were ELISA positive. ANCA-associated vasculitides (AAV), connective tissue disorders and gastrointestinal disorders represented 20.5%, 23.9%, and 21.2% of positive results, respectively. AAV patients exhibited higher rates of MPO/PR3 specificity compared to non-AAV (93.8% versus 8%). Conclusions. This first paper on Greek patients supports that screening for ANCA by IIF and confirming positive results by ELISA minimize laboratory charges without sacrificing diagnostic accuracy.

CD4+ T cells sensitized by vascular smooth muscle induce vasculitis, and interferon gamma is critical for the initiation of vascular pathology

Primary vasculitis is the result of idiopathic inflammation in blood vessel walls. T cells are believed to play a critical role, but the nature of the pathological T-cell response remains obscure. In this study, we provide evidence that CD4(+) T lymphocytes, activated in the presence of syngeneic vascular smooth muscle cells, were sufficient to induce vasculitic lesions after adoptive transfer to recipient mice. Additionally, the disease is triggered in the absence of antibodies in experiments in which both the donors of stimulated lymphocytes and the transfer recipients were mice that were deficient in B cells. Tracking and proliferation of the transferred cells and their cytokine profiles were assessed by fluorescence tagging and flow cytometry. Proliferating CD4(+) T cells were evident 3 days after transfer, corresponding to the occurrence of vasculitic lesions in mouse lungs. The transferred T lymphocytes exhibited Th1 and Th17 cytokine profiles and minimal Th2. However, 1 week after vasculitis induction, effector functions could be successfully recalled in Th1 cells, but not in Th17 cells. Additionally, in the absence of constitutive interferon-γ expression, T cells sensitized by vascular smooth muscle cells failed to induce vasculitis. In conclusion, our results show that Th1 cells play a key role in eliciting vasculitis in this murine model and that induction of the disease is possible in the absence of pathogenic antibodies.

Vasculitis

Vasculitic syndromes involving the lung present a unique challenge for pathologists because of the histologic overlap with other disorders and the clinical implications of the diagnosis in regard to clinical management. This article reviews the more common vasculitic syndromes involving the lung, concentrating primarily on Wegener granulomatosis, Churg-Strauss syndrome, necrotizing sarcoid, microscopic polyangiitis, and diffuse alveolar hemorrhage syndromes. The article focuses on a review of the recent literature, diagnostic approach, and differential diagnosis.

Clinical characteristics of cytomegalovirus infection in rheumatic diseases: multicentre survey in a large patient population

OBJECTIVE

To survey and elucidate the clinical characteristics of CMV infection in rheumatic disease patients.

METHODS

A detailed questionnaire survey on CMV infection was carried out against rheumatic disease patients hospitalized in member hospitals, and the obtained clinical and/or laboratory data were analysed.

RESULTS

Out of 7377 patients, 151 were diagnosed as having CMV infection. The underlying diseases ranged broadly, but SLE, microscopic polyangiitis, and dermatomyositis were the most common. Four were diagnosed histopathologically, and the others via positive CMV antigenaemia. In addition to oral corticosteroid for all but one patient, 81 were treated with pulsed methylprednisolone (MPSL), 64 with cyclophosphamide (CYC) and 36 with other immunosuppressants. Forty-four had a fatal outcome, for which presence of clinical symptoms, other infectious complications, lymphopenia, an older age (>59.3 yrs) and the use of pulsed MPSL were significant risk factors (P < 0.05) by univariate analysis. Multivariate analysis retained the first three (P < 0.05). The CMV antigenaemia count was significantly higher for the symptomatic than asymptomatic [10.1 (0.0-2998.0) vs 4.0 (1.3-1144.4)/10(5) PMNs, respectively, P < 0.05; threshold count: 5.6/10(5) PMNs]. No treatment benefit by anti-viral agent was observed as for survival.

CONCLUSION

CMV infection was mostly diagnosed by antigenaemia, and occurred among patients under strong immunosuppressive therapy using pulsed MPSL and/or immunosuppressants. Lymphopenia, presence of symptoms and other infections are significant risk factors for a poor outcome and pulsed MPSL and an older age may predict it. Patients were prone to be symptomatic with anti-genaemia count over 5.6/10(5) PMNs.

Cutaneous manifestations of vasculitis

OBJECTIVES

To discuss the clinical features, diagnostic evaluation, and treatment options for cutaneous vasculitis.

METHODS

The literature in the PubMed database was reviewed regarding the presentation, pathophysiology, clinical workup, and treatment of cutaneous vasculitis.

RESULTS

Available classification criteria of vasculitis are based on histopathologic criteria or clinicohistologic features. These have been designed more for research purposes than for clinical application. Skin findings such as palpable purpura, nodules, urticaria, ulcers, and infarction are clues to the presence of vasculitis. Pathologic findings of fibrinoid necrosis, infiltration by neutrophils or lymphocytes, and deposition of complement and immunoglobulin may be helpful in reaching a specific diagnosis. However, there is considerable overlap across different conditions.

CONCLUSIONS

The correct diagnosis of cutaneous manifestations of vasculitis requires an understanding of vasculitis classification, recognition of specific clinical patterns, and the ability to interpret histopathologic data.

An asthmatic adolescent with a rash and eosinophilia

Children frequently visit emergency departments with asthma exacerbations. Many of these asthmatic children may have fever and/or pneumonia, but when associated with eosinophilia or evidence of vasculitis, other diagnoses should be considered. Churg-Strauss syndrome is a rare form of systemic vasculitis, which usually occurs in patients with asthma in association with eosinophilia. The diagnosis of Churg-Strauss syndrome can be difficult because this syndrome may arise at first as a common association between asthma and allergic rhinitis. A delay in diagnosis and treatment may increase the morbidity from the complications of vasculitis. We report a young asthmatic adolescent who presented with vasculitis, eosinophilia, and peripheral neuropathy.

Antineutrophil cytoplasmic autoantibody-associated small-vessel vasculitis

PURPOSE OF REVIEW

This review focuses on recent advances in the diagnosis, pathogenesis and treatment of antineutrophil cytoplasmic autoantibody-associated small-vessel vasculitis.

RECENT FINDINGS

Antineutrophil cytoplasmic autoantibodies are closely associated with Wegener's granulomatosis and microscopic polyangiitis. Within the Churg-Strauss syndrome, antineutrophil cytoplasmic autoantibodies, mostly directed towards myeloperoxidase, characterize patients with glomerulonephritis and small-vessel vasculitis. There is increasing evidence that myeloperoxidase-antineutrophil cytoplasmic autoantibodies are directly involved in the pathogenesis of necrotizing vasculitis. This is less clear for proteinase 3-antineutrophil cytoplasmic autoantibodies, markers for Wegener's granulomatosis. With respect to proteinase 3-antineutrophil cytoplasmic autoantibodies, complementary proteinase 3, a peptide translated from the antisense DNA strand of proteinase 3 and homologous to several microbial peptides, may be involved in induction of proteinase 3-antineutrophil cytoplasmic autoantibodies. Currently, various controlled trials have been initiated. Methotrexate has been shown to be effective for induction of remission in locoregional Wegener's granulomatosis. Other trials are underway.

SUMMARY

Apart from its diagnostic potential, antineutrophil cytoplasmic autoantibodies, particularly myeloperoxidase-antineutrophil cytoplasmic autoantibodies, are directly involved in the pathogenesis of the associated vasculitides. New treatment modalities, supposedly more efficacious and less toxic than daily oral cyclophosphamide, are being tested in randomized controlled trials.

Accumulation of Tc-99m-HMPAO-labeled leukocytes in cutaneous lesions of Henoch-Schonlein purpura

A 70-year-old man with complicated cruris fracture, treated with an arthrodesis and skin transplantation, complained about persistent pain of the right ankle and skin rashes. Bone and leukocyte scintigraphy were performed because osteomyelitis was suspected. Bone scintigraphy showed abnormal uptake in the ankle. Leukocyte scintigraphy showed only multiple hot spots in the soft tissue. A cutaneous biopsy specimen revealed Henoch-Schonlein vasculitis.

Current pathological and clinical aspects of Buerger's disease in Japan

Since Buerger's disease was first described by Leo Buerger in 1908, many authors have discussed whether it indeed exists and, if so, is a definite clinical entity. Today, Buerger's disease is accepted as a definite vascular disease with a typical clinical picture, natural history, and histopathology; however, the diagnosis of Buerger's disease has been controversial, and the etiology of this vascular occlusive disease has remained unknown because many authors in different countries have their own criteria. Besides, patients with this disease have decreased in number even in Japan, while there has been no change in the number of arteriosclerosis obliterans patients. Currently, only one or two new patients per year are encountered at our outpatient clinic. The purpose of this review is to examine the current epidemiological, pathological, and clinical aspects of Buerger's disease in Japan based on the 222 patient files of our department between 1980 and 2000 and to discuss the pathogenesis, clinical presentation, and various treatment modalities.

Nephropathy, polyneuropathy, and gastroenteritis in a child with Churg-Strauss syndrome

Churg-Strauss syndrome (CSS) is a serious but rare pauci-immune vasculitis of small- and medium-sized blood vessels. It is commonly seen in association with bronchial asthma and/or allergic disorders. The syndrome is characterized by the presence of asthma, hypereosinophilia, and vasculitis in any part of the body. Vasculitis is often associated with significant distortion of normal functions. A rather severe case of CSS in an 8-year-old Nigerian girl with asthma and allergic rhinoconjunctivitis is reported. She presented with multiple morbidities, namely, vasculitic polyneuropathy and also nephritic-nephrotic syndrome that eventuated in acute renal failure after an onset of vasculitic gastroenteritis. Routine screening of all asthmatic patients for CSS is advocated.

Clinical and Histologic Determinants of Renal Outcome in ANCA-Associated Vasculitis: A Prospective Analysis of 100 Patients with Severe Renal Involvement

This study aimed to identify clinical and histologic prognostic indicators of renal outcome in patients with ANCA-associated vasculitis and severe renal involvement (serum creatinine >500 micromol/L). One hundred patients who were enrolled in an international, randomized, clinical trial to compare plasma exchange with intravenous methylprednisolone as an additional initial treatment were analyzed prospectively. Diagnostic renal biopsies were performed upon entry into the study. Thirty-nine histologic and nine clinical parameters were determined as candidate predictors of renal outcome. The end points were renal function at the time of diagnosis (GFR0) and 12 mo after diagnosis (GFR12), dialysis at entry and 12 mo after diagnosis, and death. Multivariate analyses were performed. Predictive of GFR0 were age (r = -0.40, P = 0.04), arteriosclerosis (r = -0.53, P = 0.01), segmental crescents (r = 0.35, P = 0.07), and eosinophilic infiltrate (r = -0.41, P = 0.04). Prognostic indicators for GFR12 were age (r = -0.32, P = 0.01), normal glomeruli (r = 0.24, P = 0.04), tubular atrophy (r = -0.28, P = 0.02), intraepithelial infiltrate (r = -0.26, P = 0.03), and GFR0 (r = 0.29, P = 0.01). Fibrous crescents (r = 0.22, P = 0.03) were predictive of dialysis at entry. Normal glomeruli (r = -0.30, P = 0.01) and treatment arm (r = -0.28, P = 0.02) were predictive of dialysis after 12 mo. No parameter predicted death. Both chronic and acute tubulointerstitial lesions predicted GFR12 in severe ANCA-associated glomerulonephritis, whereas plasma exchange was a positive predictor of dialysis independence after 12 mo for the entire patient group. Plasma exchange remained a positive predictor when patients who were dialysis dependent at presentation were analyzed separately (r = -0.36, P = 0.01). Normal glomeruli were a positive predictor of dialysis independence and improved renal function after 12 mo, indicating that the unaffected part of the kidney is vital in determining renal outcome.

Acute manifestations of autoimmune connective tissue diseases

Autoimmune connective tissue diseases are common conditions that often present non-specifically. Clinicians in emergency departments and acute medical assessment units may face these patients. This article provides an overview for the non-specialist clinician on the acute manifestations that may occur in these patients.

Clinical [corrected] and pathological characteristics of Chinese patients with antineutrophil cytoplasmic autoantibody associated systemic vasculitides: a study of 426 patients from a single centre

BACKGROUND

Antineutrophil cytoplasmic autoantibodies (ANCA) are serological markers of ANCA associated systemic vasculitides (AASV), which is one of the most common multisystem autoimmune diseases. Features of Chinese patients with AASV have not been fully investigated.

OBJECTIVE

To analyse the clinical and pathological characteristics of Chinese patients with AASV.

METHODS

426 Chinese patients with AASV diagnosed in the past eight years were retrospectively studied and their clinical and pathological data were analysed.

RESULTS

Of the 426 patients, 87 (20.4%) were Wegener's granulomatosis, 337 (79.1%) were microscopic polyangiitis and two (0.5%) were Churg-Strauss syndrome. Only 201 of 426 (47.2%) patients were diagnosed within three months. Clinically, the patients had multisystem involvement. Altogether 371 of 426 (87.1%) had kidney involvement and 260 of 426 (61.0%) had lung involvement. The prevalences of renal involvement and fatigue were significantly higher in patients with MPO-ANCA than that in patients with PR3-ANCA; the prevalences of ophthalmic, nasal involvement, rash, and arthragia were significantly higher in patients with PR3-ANCA than those in patients with MPO-ANCA. The one and five year death rates were 13.1% and 22.4%, respectively. The percentage of patients progressing to end stage renal disease at one and five years was 15.9% and 27.1%, respectively.

CONCLUSIONS

AASV is not a rare autoimmune disease in Chinese people. Kidney and lung were the most vulnerable organs. For patients with multiorgan damage, an ANCA test should be performed to make an early diagnosis and to start treatment in time.

On the Wegener granulomatosis associated region on chromosome 6p21.3

BACKGROUND

Wegener granulomatosis (WG) belongs to the heterogeneous group of systemic vasculitides. The multifactorial pathophysiology of WG is supposedly caused by yet unknown environmental influence(s) on the basis of genetic predisposition. The presence of anti-neutrophil cytoplasmic antibodies (ANCA) in the plasma of patients and genetic involvement of the human leukocyte antigen system reflect an autoimmune background of the disease. Strong associations were revealed with WG by markers located in the major histocompatibility complex class II (MHC II) region in the vicinity of human leukocyte antigen (HLA)-DPB1 and the retinoid X receptor B (RXRB) loci. In order to define the involvement of the 6p21.3 region in WG in more detail this previous population-based association study was expanded here to the respective 3.6 megabase encompassing this region on chromosome 6. The RXRB gene was analysed as well as a splice-site variation of the butyrophilin-like (BTNL2) gene which is also located within the respective region. The latter polymorphism has been evaluated here as it appears as a HLA independent susceptibility factor in another granulomatous disorder, sarcoidosis.

METHODS

150-180 German WG patients and a corresponding cohort of healthy controls (n = 100-261) were used in a two-step study. A panel of 94 microsatellites was designed for the initial step using a DNA pooling approach. Markers with significantly differing allele frequencies between patient and control pools were individually genotyped. The RXRB gene was analysed for single strand conformation polymorphisms (SSCP) and restriction fragment length polymorphisms (RFLP). The splice-site polymorphism in the BTNL2 gene was also investigated by RFLP analysis.

RESULTS

A previously investigated microsatellite (#1.0.3.7, Santa Cruz genome browser (UCSC) May 2004 Freeze localisation: chr6:31257596-34999883), which was used as a positive control, remained associated throughout the whole two-step approach. Yet, no additional evidence for association of other microsatellite markers was found in the entire investigated region. Analysis of the RXRB gene located in the WG associated region revealed associations of two variations (rs10548957 pallelic = 0.02 and rs6531 pallelic = 5.20 x 10-5, OR = 1.88). Several alleles of markers located between HLA-DPB1, SNP rs6531 and microsatellite 1.0.3.7 showed linkage disequilibrium with r2 values exceeding 0.10. Significant differences were not demonstrable for the sarcoidosis associated splice-site variation (rs2076530 pallelic = 0.80) in our WG cohort.

CONCLUSION

Since a microsatellite flanking the RXRB gene and two intragenic polymorphisms are associated significantly with WG on chromosome 6p21.3, further investigations should be focussed on extensive fine-mapping in this region by densely mapping with additional markers such as SNPs. This strategy may reveal even deeper insights into the genetic contributions of the respective region for the pathogenesis of WG.

Cutaneous Vasculitis Update: Diagnostic Criteria, Classification, Epidemiology, Etiology, Pathogenesis, Evaluation and Prognosis

Vasculitis, inflammation of the vessel wall, can result in mural destruction with hemorrhage, aneurysm formation, and infarction, or intimal-medial hyperplasia and subsequent stenosis leading to tissue ischemia. The skin, in part due to its large vascular bed, exposure to cold temperatures, and frequent presence of stasis, is involved in many distinct as well as un-named vasculitic syndromes that vary from localized and self-limited to generalized and life-threatening with multi-organ disease. To exclude mimics of vasculitis, diagnosis of cutaneous vasculitis requires biopsy confirmation where its acute signs (fibrinoid necrosis), chronic signs (endarteritis obliterans), or past signs (acellular scar of healed arteritis) must be recognized and presence of extravascular findings such as patterned fibrosis or collagenolytic granulomas noted. Although vasculitis can be classified by etiology, many cases have no identifiable cause, and a single etiologic agent can elicit several distinct clinicopathologic expressions of vasculitis. Therefore, the classification of cutaneous vasculitis is best approached morphologically by determining vessel size and principal inflammatory response. These histologic patterns roughly correlate with pathogenic mechanisms that, when coupled with direct immunofluorescent examination, anti-neutrophil cytoplasmic antibody (ANCA) status, and findings from work-up for systemic disease, allow for specific diagnosis, and ultimately, more effective therapy. Herein, we review cutaneous vasculitis focusing on diagnostic criteria, classification, epidemiology, etiology, pathogenesis, and evaluation of the cutaneous vasculitis patient.

Association of HLA-DRB1*0901-DQB1*0303 haplotype with microscopic polyangiitis in Japanese

Microscopic polyangiitis (MPA) is a rare and severe form of systemic necrotizing vasculitis associated with myeloperoxidase (MPO)-specific antineutrophil cytoplasmic antibody (ANCA). We previously reported significant association of HLA-DRB1*0901 with MPA. To define the susceptibility loci within the HLA region, we determined the genotypes of HLA-DQB1, DPB1, B and C in 50 patients with MPA and 77 unrelated Japanese controls. In addition to HLA-DRB1*0901, significant association of DQB1*0303 (allele carrier frequencies 50% in MPA, 29.9% in controls, odds ratio 2.35, P = 0.017) was detected. These alleles were in strong linkage disequilibrium (D' = 0.95, r2 = 0.82). Increased frequency was also observed for DPB1*0201, B*15111 and Cw*0303, which was at least partly accounted for by linkage disequilibrium with DRB1*0901 and DQB1*0303. These results indicate that DRB1*0901-DQB1*0303 haplotype represents the primary genetic risk for MPA within the HLA region in Japanese, and provides the basis that future functional studies on the role of HLA in MPA should target DR9, DQ9 and DR53 proteins encoded by this haplotype.

Estudio clínico-biológico y radiológico de la granulomatosis de Wegener en un hospital universitario

Wegener's granulomatosis is a rare systemic vasculitis that fundamentally affects the kidney and respiratory tract. Although the histological findings are very characteristic, they do not occur in all cases, which makes diagnosis difficult.

METHODS

The main clinical, biological and radiological characteristics of 13 cases of Wegener's granulomatosis diagnosed in a university hospital of the center of Spain are collected in this present paper.

RESULTS

The majority of the patients were men in their 50's. Fever and general syndrome were usual presentations of the disease. Upper respiratory tract (10 cases) and lung involvement (9), followed by renal involvement (8), were the most common. Alveolar infiltrates and bilateral nodules were the most common findings in the X-ray and thoracic CT scan, although the latter permits a greater definition of the lesions. Measurement of antibodies against cytoplasma of the neutrophils (ANCA) was positive in 8 patients (6 cANCA and 2 pANCA). Renal biopsy was used most for the histologic diagnosis, where focal and segmental glomerulonephritis was the most common finding. The majority of the patients received steroids plus cyclophosphamide as induction treatment.

CONCLUSIONS

Wegener's disease is a rare systemic vasculitis. The existence of hematuria or respiratory tract involvement in a patient with fever suggests the diagnosis. Conducting a CT scan and ANCAs measurement are useful tools for its diagnosis, since the histology is not definitive.

Detection rate and antigenic specificities of antineutrophil cytoplasmic antibodies in chinese patients with clinically suspected vasculitis

The detection rate of antineutrophil cytoplasmic antibodies (ANCA) in Chinese patients with clinically suspected small vessel vasculitis was investigated, and their antigen specificity and demographic features were analyzed. A number of sera (n = 5,604) sent to our referral laboratory for ANCA screening were tested by indirect immunofluorescence (IIF), enzyme-linked immunosorbent assays (ELISAs) for myeloperoxidase (MPO)- and proteinase 3 (PR3)-ANCA. Then the IIF-ANCA-positive sera that were negative for MPO- and PR3-ANCA were further tested by antigen-specific ELISA by using other five highly purified known ANCA antigens as solid-phase ligands. The known antigens included bactericidal/permeability-increasing protein (BPI), human leukocyte elastase (HLE), lactoferrin, cathepsin G, and azurocidins. Of the 5,604 sera, 267 (4.76%) sera were IIF-ANCA positive and 390 (7%) were antinuclear antibody (ANA) positive in the IIF assay. Of the IIF-positive samples, 213 were anti-MPO positive, 32 were anti-PR3 positive, and five cases were positive for both. Of the 48 sera positive for IIF-ANCA but negative for MPO- and PR3-ANCA, 13 sera (27%) recognized other target antigens, 7 sera recognized BPI, 5 recognized HLE, 1 recognize cathepsin G, and 1 recognized azurocidin. None of the sera recognized lactoferrin, and one serum sample recognized both BPI and HLE. The majority of ANCA-positive patients presented in summer or winter. There was no difference in gender (male/female ratio, 1:1.12) in ANCA-positive patients with a mean age of 53.1 years. The male/female ratio was 1.17:1 for patients over 60 years of age; however, it was 1:4 for patients under 20 years of age. We conclude that ANCA-related diseases are not rare in China, and the major antigens are MPO and PR3. When the IIF technique is used to detect ANCA, ANA should be carefully distinguished.

Systemic necrotizing vasculitides in Turkey: a comparative analysis of 40 consecutive patients

OBJECTIVE

The aim of this study was to analyze and compare the demographic and clinical features and prognosis of patients with different systemic necrotizing vasculitides (SNV) in Turkey.

PATIENTS AND METHODS

Twenty-three patients with Wegener's granulomatosis (WG), 15 with polyarteritis nodosa (PAN), and two with Churg-Strauss syndrome were included in the study. The clinical and laboratory features of patients with WG and PAN were compared, and survival analysis was performed for the WG patients.

RESULTS

Twenty-one patients with WG had systemic disease involving kidneys, and two had localized disease. Fifteen patients were placed in the PAN group, 12 of whom were classified as having classic PAN and three with microscopic polyangiitis. Median follow-up time was 37 months (range 1-81) for WG patients and 41 months (range 5-132) for the PAN group. Upper respiratory tract, pulmonary, and renal involvement were significantly more frequent in the WG group than in PAN. Peripheral nervous system involvement was more frequent in the PAN group. In WG, survival was calculated as 59% at 35 months. High initial vasculitis damage index scores were found to be predictive for mortality.

CONCLUSION

This study revealed that the most frequent type of SNV was WG in a tertiary rheumatology setting in Turkey. There was initial organ damage in most of the patients, frequently caused by severe renal involvement. In contrast to other published series, overt cardiovascular and gastrointestinal involvement were not observed in our patients with SNV.

Churg-Strauss Syndrome Development during Asthma Therapy with Leukotriene Receptor Antagonists: Just a Coincidental Association?

A report on our clinical experience based on 3 male patients who developed Churg-Strauss syndrome (CSS) after standard oral montelukast use. All patients affected by moderate asthma and chronic hyperplastic rhinosinusitis were treated with inhaled corticosteroids and ß2 agonists. Systemic corticosteroid treatment consisted in oral daily prednisone in case 1, in short courses of oral betamethasone in case 2, and in remote and isolated administrations of oral betamethasone and intramuscular methylprednisolone in case 3. Because of the improvement of the asthma symptoms after montelukast use, patient 1 decided to take half the dose of prednisone for 10 days and patient 2 decided to discontinue systemic and inhaled corticosteroids for 45 days. Overt CSS was heralded by vasculitic skin lesions and developed in each patient with severe organ damage, consisting in renal, myocardial and gastrointestinal involvement. Remission was obtained by standard CSS therapy after montelukast withdrawal.

According to the unmasking hypothesis, antileukotriene treatment, by enabling the reduction in systemic corticosteroid therapy in case 1 and its discontinuation in case 2, might have only permitted the precipitation of the vasculitis. However antileukotriene-associated CSS reportedly occurred in systemic corticosteroid-naïve patients and relapsed in one patient after antileukotriene treatment. These observations lend support to the concept that the precipitation of the vasculitic phase may be associated with leukotriene modifier deleterious effects. In conclusion there is not enough evidence to prove that antileukotriene treatment plays a direct causative role in the pathogenesis of CSS. Further clinical and experimental research is required to clarify the antileukotriene associated CSS controversy.

The clinical and pathological characteristics of Chinese elderly patients with anti-neutrophil cytoplasmic autoantibodies associated small vessel vasculitis

BACKGROUND

Anti-neutrophil cytoplasmic autoantibodies (ANCA) are serological markers of ANCA-associated small vessel vasculitis (AASV) which is one of common autoimmune diseases in Caucasian elderly population.

OBJECTIVE

To analyze the clinical and pathological characteristics of Chinese elderly patients with AASV.

METHODS

One-hundred forty one Chinese patients with AASV over 65 years old, diagnosed between 1997 and 2001 in the Institute of Nephrology of Peking University First Hospital, were retrospectively studied and their clinical and pathological data were analyzed.

RESULTS

Patients diagnosed with AASV patient increased chronologically with the yearly ratio in 2000 and 2001 significantly (P < 0.05) higher than that in 1998 and before. Of the 141 patients, 72 were male and 69 were female with an average age of 68.2 years. 13 of the 141 were cytoplasmic ANCA (cANCA) positive and all recognized proteinase 3 (PR3). The other 128 were perinuclear ANCA (pANCA) positive and 120/128 recognized MPO, 8/128 recognized both PR3 and MPO. Less than 50% of the patients were correctly diagnosed within 3 months. Clinically, 78% of the patients had fever and fatigue, 52.5% had body weight loss, 96.4% had kidney involvement, of which 75% had elevated serum creatinine and 30.8% had acute renal failure. 76.6% had lung involvement, over half of them had hemoptysis or lung infiltrates. Other clinical manifestations included arthralgia (48.2%), muscle pain (39.7%), gastrointestinal symptoms (39.7%), eye involvement (28.3%) and ENT involvement (31.2%). In laboratory examinations, 94.4% of the patients had anemia, 62.4% had increased WBC count, 93.6% had increased ESR and 55.1% had increased CRP.

CONCLUSIONS

More and more patients with AASV were diagnosed in Chinese elderly. Kidney was the most vulnerable organ to be involved and lung was the most important extra-renal organ to be affected. For elderly patients with multi-organ damage, an ANCA test should be performed in order to make an early diagnosis and start therapy in time.

Evaluating inflammatory joint disease: how and when can autoantibodies help?

The diagnosis of inflammatory joint disease rests on a constellation of symptoms, signs, laboratory test results and, occasionally, histological findings. Classification criteria have been developed by national learned societies, international panels of experts or, more rarely, an expert working alone. These criteria are intended to provide a common language for therapeutic trials and international publications. Yet, they are often inappropriately used as diagnostic tools for the individual patient. Identification of an early seroimmunologic marker with high sensitivity and specificity for classifying patients with recent-onset joint disease is a daunting challenge. Test performance characteristics such as sensitivity, specificity, positive and negative predictive values, and the positive or negative likelihood ratio help to assess the diagnostic usefulness of a laboratory test in a specific situation. The difference between the pretest and posttest likelihoods of obtaining a positive or negative result measures the usefulness, or performance, of a laboratory test in a specific situation according to the prevalence of the disease. A higher positive likelihood ratio indicates a more useful test. In a patient with inflammatory joint disease, the diagnosis can be sought by assaying a limited number of autoantibodies according to a decision tree. Thus, IgM rheumatoid factors (latex test or ELISA) and antibodies to filaggrin or other citrullinated proteins (antikeratin antibodies by indirect immunofluorescent assay or anticyclic citrullinated peptides by ELISA) identify more than 70% of cases of early rheumatoid arthritis with greater than 98% specificity. If these markers are negative, testing for antinuclear antibodies by indirect immunofluorescent assay on HEp-2 cells identifies 99% of cases of lupus and progressive systemic sclerosis. Confirmation of the diagnosis can be obtained by characterizing the autoantibodies: thus, presence of antidouble-stranded DNA (dsDNA, by the Farr radioimmunoassay, indirect immunofluorescent assay on Crithidia luciliae, or ELISA (IgG)) or of antinucleosome antibodies (ELISA) indicates lupus, whereas anticentromere, antitopoisomerase I (Scl 70), and antinucleolar antibodies point to progressive systemic sclerosis. A positive test for antibodies to soluble nuclear antigens of the U1 RNP type suggests mixed connective tissue disease or lupus but may indicate scleroderma. Anti-Sm antibodies are found in fewer than 10% of lupus patients but are highly specific. Anti-SSA (Ro) and anti-SSB (La) suggest lupus or primary Sjögren's syndrome. When tests are negative for ANA, several antibodies to cytoplasmic organelles are valuable diagnostic tools, such as anti-J01 for polymyositis syndromes and antiribosome antibodies for lupus, although their sensitivity is modest (20-25%). Finally antineutrophil cytoplasmic antibodies (ANCAs) ensure the diagnosis of small-vessel vasculitides, which often involve the lungs and kidneys. Thus, in diffuse Wegener's granulomatosis, ANCAs exhibiting the classic cytoplasmic pattern and corresponding by ELISA to anti-PR3 are found. In microscopic polyangiitis the ANCAs are peripheral and correspond by ELISA to antimyeloperoxidase antibodies. Tests for other antibodies are less often needed to evaluate inflammatory joint disease.