Low level autoantibodies can be frequently detected in the general Australian population

Prevalence of a large panel of systemic autoantibodies in the Bavarian adult population

Objective

Autoimmune diseases commonly feature the presence of specific humoral autoantibodies. However, the prevalence of a large panel of systemic autoantibodies has never been assessed in the general population. We, therefore, described the prevalence of about 50 humoral systemic autoantibodies in a sample of the general Bavarian adult population.

Methods

Non-fasting venous serum samples from 331 participants were analyzed for 7 autoantibody screening tests (nuclear, cytoplasmic, and mitotic ANA, ANCA, cANCA and pANCA, anti-ENA autoantibodies) and 44 different monospecific humoral non-organ specific/systemic autoantibodies using indirect immunofluorescence tests, ELISAs, and line blots. In order to assess associations between sex, age, BMI, education level, smoking status and the presence of systemic autoantibodies, logistic regression analyses were conducted.

Results

At least one screening test was positive in 29.9% of the participants, and 42.3% of the participants were seropositive for at least one monospecific autoantibody. The most frequently found monospecific autoantibodies were rheumatoid factor (35.6%), ß2-glycoprotein 1 IgM (4.8%), and cardiolipin IgG (1.8%). Only few associations between sex, age, BMI, education, smoking status and autoantibody frequencies were observed.

Conclusion

Systemic autoantibodies are common in the general Bavarian population, and largely independent of sex, age, BMI, education, or smoking status. The study results may give orientation to clinicians about the occurrence of autoantibodies in the population, not (yet) associated with clinical symptoms.

Potential Determinants of Thyroid Peroxidase Antibodies and Mortality Risk: Results From the ELSA-Brasil Study

CONTEXT

The presence of thyroid peroxidase antibodies (TPOAbs) may be considered as an indicator of adverse health outcomes.

OBJECTIVE

We aimed to investigate the potential determinants of TPOAb levels and to analyze the association between TPOAb titers and the risk of all- and specific-cause mortality.

METHODS

Baseline and longitudinal data of 13 187 participants from the ELSA-Brasil Study were analyzed. We investigated the association of TPOAb, detectability, positivity, and persistent positivity with sociodemographic and lifestyle factors using logistic regressions. Cox proportional hazards and Fine-Gray subdistribution hazard regression analyses were used to verify the association of TPOAbs with mortality.

RESULTS

The determinants of TPOAb detectability and positivity were younger age, higher body mass index, female sex, and former and current smoking status. Black, mixed, and other self-reported races, intermediate and higher education, and heavy drinking were determinants of detectable and positive TPOAb levels. Female sex, White race, and former smoking were determinants of persistent TPOAb positivity at 2 visits, although only the female sex maintained its association at 3 visits. Moreover, after multivariate adjustment, there were associations between higher levels of TPOAbs and higher risk of cancer-related mortality among men, and TPOAb detectability and mortality by other causes among women.

CONCLUSION

Sociodemographic and lifestyle-related factors were determinants of multiple TPOAb categories. TPOAb levels were associated with mortality risk; however, the low mortality rate in this sample might have compromised this finding. We suggest further studies to explore the clinical importance of detectable TPOAb levels, not only its positivity, as a potential marker of inflammation.

Global prevalence and epidemiological trends of Hashimoto's thyroiditis in adults: A systematic review and meta-analysis

Objective

Although Hashimoto's thyroiditis is associated with cardiovascular disease and malignancy, the global status of Hashimoto's thyroiditis is not well characterized across regions. Our objective was to evaluate the prevalence and trends of Hashimoto's thyroiditis in adults in regions with different economic income levels around the world.

Methods

For this systematic review and meta-analysis, we searched PubMed, Embase, MEDLINE, Scopus, and Web of Science databases, and 48 random-effects representative studies from the inception to June 2022 were included without language restrictions to obtain the overall prevalence of Hashimoto's thyroiditis in adults worldwide. In addition, we stratified by time of publication, geographic region, economic level of the region of residence, gender, diagnostic method, etc.

Results

A total of 11,399 studies were retrieved, of which 48 met the research criteria: 20 from Europe, 16 from Asia, five from South America, three from North America, and three from Africa. Furthermore, there are two projects involving 19 countries and 22,680,155 participants. The prevalence of Hashimoto's thyroiditis was 7.5 (95%CI 5.7-9.6%), while in the low-middle-income group the prevalence was 11.4 (95%CI 2.5-25.2%). Similarly, the prevalence was 5.6 (95%Cl 3.9-7.4%) in the upper-middle-income group, and in the high-income group, the prevalence was 8.4 (95%Cl 5.6-11.8). The prevalence of Hashimoto's varied by geographic region: Africa (14.2 [95% CI 2.5-32.9%]), Oceania (11.0% [95% CI 7.8-14.7%]), South America and Europe 8.0, 7.8% (95% Cl 0.0-29.5%) in North America, and 5.8 (95% Cl 2.8-9.9%) in Asia. Although our investigator heterogeneity was high (I²), our results using a sensitivity analysis showed robustness and reliability of the findings. People living in low-middle-income areas are more likely to develop Hashimoto's thyroiditis, while the group in high-income areas are more likely to develop Hashimoto's thyroiditis than people in upper-middle-income areas, and women's risk is about four times higher than men's.

Conclusions

Global Hashimoto's thyroiditis patients are about four times as many as males, and there are discrepancies in the regions with different economic levels. In low-middle-income areas with a higher prevalence of Hashimoto's thyroiditis, especially countries in Africa, therefore local health departments should take strategic measures to prevent, detect, and treat Hashimoto's thyroiditis. At the same time, the hidden medical burden other diseases caused by Hashimoto's thyroiditis should also be done well.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD 42022339839.

Determinants and Clinical Implications of Thyroid Peroxidase Antibodies in Middle-Aged and Elderly Individuals: The Rotterdam Study

Background: Thyroid peroxidase antibodies (TPO-Abs) play an important role in autoimmune thyroid disease, but are also prevalent in healthy individuals. However, it is unclear what determinants may influence the occurrence of TPO-Abs in healthy individuals and how TPO-Abs may affect health outcomes in these individuals. We aimed to identify determinants of TPO-Abs in a large, prospective population-based cohort of middle-aged and elderly individuals and to subsequently assess the association between TPO-Abs and risk of overall and cause-specific mortality. Methods: We performed binomial and multinomial logistic regression analyses to obtain odds ratios (ORs) and 95% confidence intervals [95% CIs] for the association of potential determinants based on previous literature with TPO-Ab positivity (>35 kU/L), TPO-Ab detectability (>5 kU/L), and TPO-Ab categories. Cox proportional hazards regression analyses were performed to obtain hazard ratios (HRs) and CIs for the association between TPO-Abs and mortality risk. Results: In 9685 participants (57% women, median baseline age 63.3 years, median follow-up time 10.1 years), we identified female sex (OR = 2.47 [CI 2.13-2.86]) and current smoking (OR = 3.10 [CI 2.66-3.62]) as determinants of TPO-Ab positivity and TPO-Ab detectability, respectively. Higher age (OR = 0.98 [CI 0.97-0.98]) and all categories of alcohol consumption (ORs ranging from 0.71-0.78) were associated with lower odds of TPO-Ab detectability. TPO-Ab detectability was associated with a higher risk of overall (HR = 1.09 [CI 1.01-1.17]), cancer-related (HR = 1.18 [CI 1.01-1.38]), and cardiovascular mortality (HR = 1.21 [CI 1.01-1.45]). Interestingly, this was more prominent in men compared with women (HR for cardiovascular mortality 1.50 vs. 0.99, respectively). Conclusions: In community-dwelling middle-aged and elderly individuals, female sex and current smoking are the most important determinants associated with TPO-Ab levels in the detectable and positive range, whereas alcohol consumption is associated with lower odds of TPO-Abs. The clinical importance of detectable TPO-Ab levels is illustrated by the association with an increased mortality risk, mainly in men. Our results warrant further exploration of the clinical applicability of detectable TPO-Ab levels, potentially as a marker for low-grade inflammation. The Rotterdam Study has been entered into the Netherlands National Trial Register (NTR; www.trialregister.nl) and into the WHO International Clinical Trials Registry Platform (ICTRP; www.who.int/ictrp/network/primary/en/) under shared catalogue number NTR6831.

Serum ANCA and Overall Mortality: A 10-Year Retrospective Cohort Study on 1,024 Italian Subjects

Background

Antineutrophil cytoplasmic antibodies (ANCA) are primarily involved in the pathogenesis of ANCA-associated vasculitides (AAV). However, ANCA may also be present in healthy subjects and in patients with autoimmune disorders different from AAV. We hypothesized that serum ANCA are associated with a worse prognosis in disorders other than AAV.

Objective

We investigated the association between the overall survival and the presence of serum ANCA in 1,024 Italian subjects with various testing indications in a 10-year interval.

Methods

In this retrospective cohort study, a population of 6,285 patients (many of whom were subsequently excluded due to our criteria) who tested for ANCA at a single center in 10 years was considered, and life status and comorbidities of subjects were collected. We compared the overall survival of ANCA-positive and ANCA-negative patients by means of Kaplan-Meier curves, while a multivariable adjusted Cox regression was used to evaluate the association between the ANCA status and the outcome (death) in terms of hazard ratios (HR) with 95% confidence intervals (CI).

Results

The positivity of perinuclear ANCA (pANCA) increased significantly mortality (HR, 1.60; 95% CI, 1.10–2.32), while cytoplasmic ANCA (cANCA) positivity failed to show a significant association (HR, 1.43; 95% CI, 0.77–2.68). The increased mortality rate was observed for both pANCA and cANCA in patients suffering from rheumatic disorders. No association was found between mortality and anti-MPO (HR, 0.63; 95% CI, 0.20–2.00) or anti-PR3 (HR, 0.98; 95% CI, 0.24–3.96) after adjusting for confounders.

Conclusions

Serum pANCA and cANCA are independent negative prognostic factors in patients with concurrent autoimmune diseases.

Myeloperoxidase and associated lung disease: Review of the latest developments

Myeloperoxidase (MPO) anti-neutrophil cytoplasmic antibodies (ANCA) are often detected in association with a variety of lung pathologies, the most common being interstitial lung disease (ILD). A growing cohort of patients are being diagnosed with MPO-ANCA in the context of ILD without ANCA-associated vasculitis. Clinically and radiologically, there is little to differentiate this cohort from MPO-ANCA-negative ILD patients; however, the pathophysiology is likely different and different treatments are likely required. We present here a brief summary of the proposed pathophysiology of MPO-ANCA-positive ILD, and a more detailed review of the latest evidence on management, including monitoring for development of ANCA-associated vasculitis, immunosuppression, anti-fibrotics, and novel agents that have yet to be trialled in human experiments.

Prospective Phase II trial of radiation therapy in localised non-gastric marginal zone lymphoma with prospective evaluation of autoimmunity and Helicobacter pylori status: TROG 05.02/ALLG NHL15

BACKGROUND

This Phase 2 multicentre trial in localised non-gastric marginal zone lymphoma (MZL) evaluated the effectiveness and safety of radiotherapy and documented markers of autoimmunity and Helicobacter pylori infection.

PATIENTS AND METHODS

Eligible patients had Stages I and II or paired-organ, non-gastric MZL. Bone marrow evaluation, autoantibody panel, and H. pylori evaluation were mandatory. Involved-field or involved-site radiotherapy was delivered to 24-30.6 Gy. Detected H. pylori infections underwent eradication.

RESULTS

Between 2006 and 2014, six centres enrolled 70 patients, and 68 commenced treatment. The median age was 59 (range: 23-84) years, and 31 (46%) were male. Overall, 55 patients had Stage I disease, nine patients had Stage II disease, and four patients had paired organ-confined disease. Involved extranodal sites with three or more cases were orbital (n = 18), conjunctiva (n = 13), lacrimal (n = 8), skin (n = 8), salivary (n = 7), and muscle (n = 4). Eight patients had primary nodal MZL. At the median follow-up of 5 years (range 0.7-9.4), progression-free survival and overall survival were 79% and 95%, respectively. One lymphoma-related death and two in-field failures (after 25 and 30 Gy, respectively) occurred. Distant relapse sites were skin (n = 2), lymph nodes (n = 2), duodenum, stomach, muscle, and conjunctiva (1 each). No paired-organ MZL relapsed. Apart from cataracts (n = 18), only three treatment-related late grade ≥3 adverse events occurred. Autoantibodies or autoimmune events were detected in 26 of 68 patients (38%). H. pylori infection was detected in 15 of 63 patients (24%) tested. Neither autoimmunity nor H. pylori was detected in 27 of 68 patients (40%).

CONCLUSIONS

Radiotherapy was a potentially curative treatment with low toxicity in localised non-gastric MZL. Autoimmunity, H. pylori infection or both were detected in 60% of patients.

IgA nephropathy with serum ANCA positivity: case series and literature review

The co-occurrence of IgA nephropathy (IgAN) and positive anti-neutrophil cytoplasmic autoantibodies (ANCA) serology is uncommon. In the present case series and literature review, we aimed to clarify the impact of ANCA on pathogenesis, clinical and histopathology presentation, and outcome in IgAN patients. We report four patients with an overlap lesion of IgAN-ANCA positive. Also, we performed a narrative review of all biopsy-proven published case series. Only 1.2% patients had ANCA in our 330-biopsy-proven IgAN cohort. We compared our data with previous reports-6 case series and 3 small retrospective studies-a total of 103 patients. All patients but one had eGFR below 15 mL/min at diagnosis. Besides rapidly decreasing eGFR, all presented with proteinuria around 1.5 g/day and dysmorphic microhematuria, suggesting glomerular inflammation. Systemic symptoms suggestive for ANCA vasculitis were seen in half of our patients, but only one patient had hemorrhagic alveolitis. Patients from our cohort responded to the intensive immunosuppressive regimens used in ANCA-positive vasculitis with renal involvement. However, in the follow-up, one patient had a relapse followed by septic shock related to immunosuppression and one patient started hemodialysis. In the review, we found that IgAN-ANCA -positive patients are characterized by vasculitis-like lesions and clinically by a rapidly progressive decline in kidney function, which was reversed by an aggressive induction immunosuppressive protocol used in ANCA vasculitis. Checking ANCA serology seems useful in patients with rapidly progressive IgAN for therapeutic and prognostic reasons.

The biology, pathogenetic role, clinical implications, and open issues of serum anti-neutrophil cytoplasmic antibodies

Anti-neutrophil cytoplasmic antibodies (ANCA) are a group of autoantibodies, predominantly IgG, involved in the pathogenesis of several autoimmune disorders, detected either through indirect immunofluorescence or enzyme-linked immunosorbent assay. By means of indirect immunofluorescence, the main patterns are C-ANCA (cytoplasmic) and P-ANCA (perinuclear), while proteinase 3 (PR3) and myeloperoxidase (MPO) represent the main autoantigens in granulomatosis with polyangiitis and microscopic polyangiitis, both belonging to the family of ANCA-associated vasculitis (AAV). While several experiments established the pathogenicity of MPO-ANCA, evidence remains elusive for PR3-ANCA and an additional target antigen, i.e. LAMP2, has been postulated with specific clinical relevance. The presence of a subset of AAV without ANCA may be explained by the presence of further target antigens or the presence of molecules in blood which make ANCA undetectable. A rise in ANCA titers is not necessarily predictive of a flare of disease in AAV if not accompanied by clinical manifestations. ANCA may develop through variable mechanisms, such as autoantigen complementarity, apoptosis impairment, neutrophil extracellular traps dysfunction and molecular mimicry. We will provide herein a comprehensive review of the available evidence on the biological mechanisms, pathogenetic role, and clinical implications of ANCA testing and disease management. Further, we will address the remaining open challenges in the field, including the role of ANCA in inflammatory bowel disease and in cocaine-induced vasculitis.

Utility of repeated antinuclear antibody tests: a retrospective database study

BACKGROUND

Anti-nuclear antibody (ANA) testing is frequently used as a diagnostic or screening test in patients with inflammatory or musculoskeletal symptoms. The value of repeat testing is unclear. We sought to evaluate the frequency, utility, and cost of repeat ANA testing. The main objective was to assess the positive predictive value of a repeat ANA test for the diagnosis of rheumatological conditions associated with ANA.

METHODS

In this retrospective cohort study, we analysed data from a single, multisite tertiary health network in Australia across a 7-year period. ANA and other autoimmune test results were obtained from the hospital pathology system with a positive ANA titre cutoff set at 1:160. Clinical information was sourced from clinical information systems on any patient who had a change in ANA result from negative to positive on repeat testing. The cost of repeated ANA testing was calculated using the Australian Government Medicare Benefits Schedule.

FINDINGS

From March 19, 2011, to July 23, 2018, a total of 36 715 ANA tests were done in 28 840 patients at a total cost of US$675 029 (2018 equivalent). 14 058 (38·3%) of these ANA tests were positive. 7875 (21·4%) of the ordered tests were repeats in 4887 (16·9%) of the patients, among whom 2683 (54·9%) had initially negative tests, and 2204 (45·1%) had initially positive tests. 511 (19·0%) of the 2683 patients with initially negative tests had a positive result on at least one repeat test, with a median time to first positive result of 1·74 years (IQR 0·54-3·60). A change from negative to positive ANA was associated with a new diagnosis in only five (1·1%) of the 451 patients with clinical information available and no previous diagnosis of an ANA-associated rheumatological condition, yielding a positive predictive value of 1·1% (95% CI 0·4-2·7).

INTERPRETATION

Repeat ANA testing after a negative result has low utility and results in high cost.

FUNDING

Monash Health.

Frequent occurrence of low-level positive autoantibodies in chronic hepatitis C

Evidence of autoimmune disease associated with hepatitis C virus (HCV)-infection has important clinical implications. A systematic profile of these autoantibodies in relevant clinical cohorts relative to healthy controls is needed to better inform current standard of care for chronic hepatitis C. Samples from an Australian cohort of chronic HCV-infected subjects (n=127) were tested for the presence of 19 diagnostic autoantibodies and compared with data available from a control cohort representing a general Caucasian population (n=198). Chronic HCV-infected individuals had a greater number of autoantibodies than controls (p<0.0001). Anti-nuclear antibodies (ANA) followed by anti-smooth muscle antibodies (SMA) were the most frequently detected autoantibodies within the HCV cohort and significantly more than in the control cohort (p<0.0001 and p=0.006, respectively). However, for most autoantibody assays the 95th percentile approximated the reference value for positivity. None of the autoantibodies were significantly associated with age or sex for the HCV cohort, except SMA positivity that was significantly higher in chronic HCV-infected male subjects (p<0.0001). Autoantibodies found in chronic HCV-infected subjects were commonly low positive and not disease-specific. Accordingly, general screening for autoimmunity in HCV-infected subjects should not be performed unless there is high clinical suspicion of an underlying autoimmune disease.

Autoantibodies in interstitial lung diseases

The role of autoantibody testing for patients with interstitial lung disease is an evolving area. Recent guidelines recommend routine anti-nuclear antibodies, rheumatoid factor, and anti-citrullinated cyclic peptide antibody testing for patients undergoing diagnostic evaluation for interstitial lung disease, with further autoantibody testing reserved for selected cases guided by rheumatological features. Even this approach may miss patients with clinically significant autoantibodies when interstitial lung disease is the dominant or first manifestation of autoimmune disease. We retrospectively performed autoimmune serology in a clinically well characterised cohort of interstitial lung disease patients. Using stored serum, additional testing was performed to ensure all patients had complete autoantibody profiles including anti-nuclear antibodies, extractable nuclear antigen antibodies, double-stranded DNA antibodies, rheumatoid factor, anti-citrullinated cyclic peptide antibodies, anti-neutrophil cytoplasmic antibodies, and myositis antibodies. Eighty patients with interstitial lung disease, and available stored serum, were assessed. Mean age at interstitial lung disease diagnosis was 65.2 years and 42 patients were male. Positive autoimmune serology was found in 56 of 80 (70.0%) patients; the most common positive result was anti-nuclear antibodies (n=34; 42.5%). Myositis antibodies were detected in 13 of 80 (16.2%) patients. Four (5%) patients had elevated anti-citrullinated cyclic peptide antibodies, and two (2.5%) patients had detectable myeloperoxidase antibodies. Eleven (13.7%) patients with negative anti-nuclear antibodies had other significant disease associated autoantibodies. An extended panel of autoantibody testing may detect cases of connective tissue disease associated interstitial lung disease, regardless of clinical or radiological subtype, and prior to extra-pulmonary manifestations of systemic autoimmunity.

Individual and stable autoantibody repertoires in healthy individuals

In the era towards precision medicine, we here present the individual specific autoantibody signatures of 193 healthy individuals. The self-reactive IgG signatures are stable over time in a way that each individual profile is recognized in longitudinal sampling. The IgG autoantibody reactivity towards an antigen array comprising 335 protein fragments, representing 204 human proteins with potential relevance to autoimmune disorders, was measured in longitudinal plasma samples from 193 healthy individuals. This analysis resulted in unique autoantibody barcodes for each individual that were maintained over one year's time. The reactivity profiles, or signatures, are person specific in regards to the number of reactivities and antigen specificity. Two independent data sets were consistent in that each healthy individual displayed reactivity towards 0-16 antigens, with a median of six. Subsequently, four selected individuals were profiled on in-house produced high-density protein arrays containing 23,000 protein fragments representing 14,000 unique protein coding genes. Based on a unique, broad and deep longitudinal profiling of autoantibody reactivities, our results demonstrate a unique autoreactive profile in each analyzed healthy individual. The need and interest for broad-ranged and high-resolution molecular profiling of healthy individuals is rising. We have here generated and assessed an initial perspective on the global distribution of the self-reactive IgG repertoire in healthy individuals, by investigating 193 well-characterized healthy individuals. Highlights A unique longitudinal profiling of autoantibody repertoires in healthy individuals Autoantibody profiles are highly individual and stable over time All individuals display IgG binding to human protein fragments The specificity of disease associated autoantigens needs to be thoroughly characterized The identification of a small set of highly reactive autoantigens Importance of stringent antigen and sample specific cut-offs for defining reactivity.

Immunoglobulin G (IgG) anticardiolipin antibodies and recurrent cardiovascular events. A systematic review and Bayesian meta-regression analysis

BACKGROUND

Anticardiolipin antibodies of the immunoglobulin G isotype (IgG aCL) have been suggested as risk factor for arterial and venous thrombosis. No conclusive data in patients with coronary artery disease (CAD) do exist. We investigate the risk of recurrent CAD according to the presence of IgG aCL.

METHODS

We performed a systematic review and meta-analysis to evaluate the risk of recurrent major adverse cardiac events (MACE) associated with the presence of IgG aCL in patients with CAD. MEDLINE and Cochrane databases were searched. We conducted a meta-analysis of the relative risk (RR) both at 12 and 24 months.

RESULTS

We included 11 eligible studies with a total of 2425 patients, 283 IgG aCL+ and 2142 IgG aCL-. The prevalence of IgG aCL+ ranged from 6.1% to 43.3%. A total of 341 cardiac events were reported: 71 (25.1%) in IgG aCL+ and 270 (12.6%) in IgG aCL- patients. We found an increased risk of recurrent MACE in patients with high IgG aCL both at 12 (RR 2.17, 2.5-97.5%CI, 1.54-3.00) and 24 months (RR 2.11, 2.5-97.5%CI, 1.62-2.66). This association was even stronger in patients with juvenile CAD (i.e. <50 years) at both 12 (RR 3.21, 2.5-97.5%CI, 1.74-5.41) and 24 months (RR 3.24, 2.5-97.5%CI, 1.84-5.21).

CONCLUSION

Patients with CAD and elevated IgG aCL have a doubled risk of recurrent MACE at 12 and 24 months. The presence of aCL should be suspected in patients with recurrent CAD events or in patients with juvenile CAD.

High Seroprevalence of Autoantibodies Typical of Autoimmune Liver Disease in Eastern Ethiopia: Is Chewing of Khat (Catha edulis) a Triggering Factor?

BACKGROUND

Recent studies have identified chewing of khat (Catha edulis) as an independent risk factor for liver injury; however, the pathogenetic mechanism remains poorly understood. Case series have found markers of autoimmune hepatitis in patients with khat-related liver disease, suggesting that khat chewing might trigger an autoimmune response. The aims of the present study were (i) to assess the prevalence of autoantibodies typical for autoimmune liver diseases in a healthy population in Ethiopia and (ii) to explore the hypothesis that khat usage triggers autoimmunity.

METHODS

Consenting adults (≥18 years) without known autoimmune disease or manifest liver disease were included. One-hundred-and-sixty-nine individuals with current khat use were compared to 104 individuals who never used khat. Seroprevalence of antinuclear (ANA), antismooth muscle (SMA), and antimitochondrial antibodies (AMA) were determined and compared between the groups using logistic regression models to adjust for age and sex.

RESULTS

Overall, 2.6% of the study subjects were positive for ANA, 15.4% for SMA, and 25.6% for AMA. When comparing khat users to nonusers, ANA was detected in 4.1% vs. 0% (p=0.047), SMA in 16.0% vs. 14.4% (p=0.730), and AMA in 24.9% vs. 26.9% (p=0.704). ANA was excluded from multivariable analysis since there was no seropositive in the reference group. After adjusting for sex and age, no significant association between khat use and SMA or AMA was found.

CONCLUSIONS

No association between khat usage and the seropresence of SMA or AMA was found, weakening the hypothesis that khat-related liver injury is mediated through autoimmune mechanisms. However, the seroprevalences of AMA and SMA were strikingly high in this Ethiopian population compared to global estimates, suggesting that diagnostic algorithms for autoimmune liver diseases developed in Europe and North America might lead to misdiagnosis of patients on the African continent.

Autoimmune antibodies and asbestos exposure: Evidence from Wittenoom, Western Australia

BACKGROUND

Studies comparing different forms of asbestos are rare, and limited by the failure to compare results with unexposed populations. We compare autoimmune responses among former workers and residents of the crocidolite mining and milling town of Wittenoom, Western Australia, with an unexposed population.

METHODS

ANA testing using indirect immunofluorescence was performed on randomly selected serum samples from Wittenoom workers or residents and compared with those from participants of another unexposed cohort study.

RESULTS

ANA scores were higher in the Wittenoom participants compared with Busselton and the odds of being ANA positive was fivefold greater among Wittenoom participants than Busselton (OR 5.5, 95%CI 2.3-13.0).

CONCLUSIONS

This study is the first to report increased ANA positivity among persons exposed exclusively to crocidolite. This finding of a high frequency of positive ANA tests among crocidolite-exposed subjects may be an indicator for an increased risk of systemic autoimmune diseases and needs further scrutiny.

The high frequency of autoantibodies in HIV patients declines on antiretroviral therapy

Autoantibodies have been described in samples from HIV positive patients, but the effects of antiretroviral therapy (ART) remain unclear. In a retrospective longitudinal study, we applied clinical assays for autoantibodies to sera collected from 13 HIV positive patients as they began ART with <210 CD4 T-cells/μL and over 2 years on treatment. Twelve of the 13 patients had at least one autoantibody. The frequency peaked before ART (21 from 156 assays) and declined to 8/143 positive reactions after 2 years. As anti-smooth muscle (ASM) antibodies remained common, these assays were applied to HIV patients (n = 67) who had <50 copies HIV RNA/mL plasma after 13 (2-17) years on ART, and healthy controls (n = 55). The frequency of ASM was high in these patients and correlated with levels of total IgG. Hence the high frequency of autoantibodies before ART declined, but did not disappear, with successful therapy. Autoantibody levels may reflect B-cell hyperactivity in patients stable on ART.

The spectrum, incidence, kinetics and management of endocrinopathies with immune checkpoint inhibitors for metastatic melanoma

OBJECTIVE

Endocrine immune-related adverse events (endocrinopathies) are increasingly prevalent with the use of immune checkpoint inhibitors for the treatment of metastatic melanoma and other malignancies. There are no evidence-based guidelines for the screening or management of such patients. To describe the spectrum, incidence, kinetics and management of endocrinopathies with immune checkpoint inhibitors.

DESIGN

A prospective study conducted at Melanoma Institute Australia between April 2014 and October 2015.

METHODS

A total of 177 patients were treated with (a) ipilimumab (n = 15), (b) anti-PD-1 (nivolumab, pembrolizumab) (n = 103) or (c) combination ipilimumab and anti-PD-1 (n = 59) and were screened and managed for the subsequent endocrinopathies. The main outcome measures were the incidence and kinetics of endocrinopathy by immunotherapy drug class.

RESULTS

Thirty-one patients (18%) developed an endocrine immune-related adverse event (thyroid dysfunction: 14%, hypophysitis: 6% and autoimmune diabetes: 0.6%). Combination immunotherapy was more likely to result in a single or multiple endocrinopathy compared to anti-PD-1 monotherapy (27% vs 9% and 7% vs 0% respectively, P < 0.01). Endocrinopathies occurred after a median of 8 weeks from treatment commencement (range: 12-225 days), with combination immunotherapy resulting in significantly earlier onset compared to ipilimumab (median: 30 vs 76 days, P = 0.046). The majority of endocrinopathies were identified in asymptomatic patients with hormonal screening. There were no baseline predictors for endocrinopathy.

CONCLUSIONS

Combination immunotherapy has a greater risk of development of endocrinopathy compared to anti-PD-1 monotherapy. Regular biochemical profiling of patients, particularly within the first twelve weeks, results in early detection of endocrinopathy to minimise morbidity.