Silica-associated systemic lupus erythematosus in an elderly man

Silica-associated systemic lupus erythematosus with lupus nephritis and lupus pneumonitis: A case report and a systematic review of the literature

INTRODUCTION

Several epidemiological studies have shown that silica exposure triggers the onset of systemic lupus erythematosus (SLE); however, the clinical characteristics of silica-associated SLE have not been well studied.

PATIENT CONCERNS

A 67-year-old man with silicosis visited a primary hospital because of a fever and cough. His respiratory condition worsened, regardless of antibiotic medication, and he was referred to our hospital.

DIAGNOSIS

The patient showed leukopenia, lymphopenia, serum creatinine elevation with proteinuria and hematuria, decreased serum C3 level, and was positive for anti-double stranded DNA antibody, anti-nuclear antibody, and direct Coombs test. He was diagnosed with SLE. Renal biopsy was performed, and the patient was diagnosed with lupus nephritis (class IV-G(A/C) + V defined by the International Society of Nephrology/Renal Pathology Society classification). Computed tomography revealed acute interstitial pneumonitis, bronchoalveolar lavage fluid showed elevation of the lymphocyte fraction, and he was diagnosed with lupus pneumonitis.

INTERVENTIONS

Prednisolone (50 mg/day) with intravenous cyclophosphamide (500 mg/body) were initiated.

OUTCOMES

The patient showed a favorable response to these therapies. He was discharged from our hospital and received outpatient care with prednisolone slowly tapered off. He had cytomegalovirus and herpes zoster virus infections during treatment, which healed with antiviral therapy.

REVIEW

We searched for the literature on sSLE, and selected 11 case reports and 2 population-based studies. The prevalence of SLE manifestations in sSLE patients were comparative to that of general SLE, particularly that of elderly-onset SLE. Our renal biopsy report and previous reports indicate that lupus nephritis of sSLE patients show as various histological patterns as those of general SLE patients. Among the twenty sSLE patients reported in the case articles, three patients developed lupus pneumonitis and two of them died of it. Moreover, two patients died of bacterial pneumonia, one developed aspergillus abscesses, one got pulmonary tuberculosis, and one developed lung cancer.

CONCLUSION

Close attention is needed, particularly for respiratory system events and infectious diseases, when treating patients with silica-associated SLE using immunosuppressive therapies.

Lupus Pleuritis with Silicotic Nodules in the Parietal Pleura

A 63-year-old man with occupational exposure to silica presented with cutaneous ulcer, pleuritic pain, and a fever. Laboratory data showed lymphopenia and positive serum antinuclear and anti-DNA antibodies. Computed tomography of the chest showed egg shell-like calcification of the hilar and mediastinal lymph nodes without pulmonary parenchymal involvement of silicosis. A surgical biopsy showed silicotic nodules with surrounding infiltration of lymphocytes and plasma cells in the parietal pleura. With a diagnosis of systemic lupus erythematosus (SLE), systemic corticosteroid therapy was given, which led to the resolution of symptoms and laboratory abnormalities. We discuss the relationship between silica exposure and the development of SLE.

Clinical evaluation of CENP-B and Scl-70 autoantibodies in silicosis patients

Silicosis patients (SIL) suffer from respiratory disorders and dysregulation of autoimmunity. Frequent complications such as rheumatoid arthritis, systemic sclerosis (SSc) and vasculitis are known in SIL. Furthermore, we reported previously that some SIL exhibited better respiratory conditions in association with a worse immunological status. In this study, the clinical roles of anti-CENP-B and Scl-70 autoantibodies in SIL were analyzed. The titer index (Log10) of anti-CENP-B autoantibody in SIL was higher than that of healthy volunteers (HV), and that of SSc was higher than those of HV and SIL. This titer index was positively correlated with an assumed immune status of 1 for HV, 2 for SIL, and 3 for SSc. Moreover, although factor analysis revealed that the titer index of the anti-CENP-B autoantibody formed the same factor with the anti-Scl-70 autoantibody, IgG value and age in SIL cases, another extracted factor indicated that the IgA value and anti-Scl-70 antibody were positively related, but anti-CENP-B showed an opposite pattern in the results of the factor analysis. These findings indicated that the titer index of anti-CENP-B autoantibody may be a biomarker for dysregulation in SIL cases. Future clinical follow-up of SIL may therefore require both respiratory and immunological assessment.

Overlap syndrome with Sjögren's syndrome and systemic sclerosis in a steel rolling mill worker: a case report

BACKGROUND

There are few reports about work-related factors associated with Sjögren's syndrome. We report a case of overlap syndrome with Sjögren's syndrome and systemic sclerosis.

CASE PRESENTATION

A 54-year-old man was admitted due to dyspnea on exertion. The results of physical examination and laboratory findings were compatible with Sjögren's syndrome with systemic sclerosis. The patient had no pre-existing autoimmune disease, and denied family history of autoimmune disease. The patient worked in the large-scale rolling department of a steel manufacturing company for 25 years. Hot rolling is a rolling process performed at between 1100 °C and 1200 °C, generating a high temperature and a large amount of fumes, involving jet-spraying of water throughout the process to remove the instantaneously generated oxide film and prevent the high generation of fumes. In this process, workers could be exposed to silica produced by thermal oxidation. Other potential toxic substances including nickel and manganese seemed to be less likely associated with the patient's clinical manifestations.

CONCLUSIONS

Occupational exposure to silica seemed to be associated with the patient's clinical manifestations of overlap syndrome with Sjögren's syndrome and systemic sclerosis. Although the underlying mechanism is still unclear, autoimmune disease including Sjögren's syndrome affects women more often than men and there was no family history of autoimmune disease. These suggested that there was an association between occupational silica exposure and the disease of the patient. Future research about the association between long-term low dose exposure to silica and the development of autoimmune diseases should be encouraged.

Two Cases of Tsunami Dust Pneumonia: Organizing Pneumonia Caused by the Inhalation of Dried Tsunami Sludge after the 2011 Great East Japan Earthquake

We report two cases of organizing pneumonia (OP) secondary to the inhalation of the dried tsunami sludge which formed during the 2011 Great East Japan Earthquake and the consequent tsunami. After the disaster, both of these patients had been engaged in the restoration work. About half a month later, they developed shortness of breath and pulmonary infiltrates. These patients were diagnosed with interstitial pneumonia. Their biopsy specimens revealed multifocal peribronchiolitis and OP. An electron probe microanalysis of these specimens demonstrated the presence of elements from the earth's crust in the inflammatory lesions. These two cases indicate that exposure to dried tsunami sludge can cause OP.

The pathologist's view of silicosis in 1930 and in 2015. The Johannesburg Conference legacy

The 1930 International Labour Office Conference on silicosis in Johannesburg was a turning point in the history of silicosis and in the recognition of the associated pathologic patterns. Since 1930, pneumoconioses such as silicosis have become much rarer in developed countries and can now be diagnosed at an early stage based on clinical and radiologic criteria. However, in spite of these advances, pathologists must remember to look for silica in tissues, particularly when clinical and radiologic findings are more uncertain. Furthermore, nowadays pathologists essentially observe silicotic lesions as incidental findings adjacent to lung cancers. In addition to identifying the characteristic lesions, pathologists must also try to identify their causative agent, in the case of crystalline silica firstly by using polarized light examination, followed as appropriate by more sophisticated devices. Finally, pathologists and clinicians must always keep in mind the various implications of exposure to silica compounds in a wide range of diseases.

Acute exposure to silica nanoparticles aggravate airway inflammation: different effects according to surface characteristics

Silica nanoparticles (SNPs) are widely used in many scientific and industrial fields despite the lack of proper evaluation of their potential toxicity. This study examined the effects of acute exposure to SNPs, either alone or in conjunction with ovalbumin (OVA), by studying the respiratory systems in exposed mouse models. Three types of SNPs were used: spherical SNPs (S-SNPs), mesoporous SNPs (M-SNPs), and PEGylated SNPs (P-SNPs). In the acute SNP exposure model performed, 6-week-old BALB/c female mice were intranasally inoculated with SNPs for 3 consecutive days. In the OVA/SNPs asthma model, the mice were sensitized two times via the peritoneal route with OVA. Additionally, the mice endured OVA with or without SNP challenges intranasally. Acute SNP exposure induced significant airway inflammation and airway hyper-responsiveness, particularly in the S-SNP group. In OVA/SNPs asthma models, OVA with SNP-treated group showed significant airway inflammation, more than those treated with only OVA and without SNPs. In these models, the P-SNP group induced lower levels of inflammation on airways than both the S-SNP or M-SNP groups. Interleukin (IL)-5, IL-13, IL-1β and interferon-γ levels correlated with airway inflammation in the tested models, without statistical significance. In the mouse models studied, increased airway inflammation was associated with acute SNPs exposure, whether exposed solely to SNPs or SNPs in conjunction with OVA. P-SNPs appear to be relatively safer for clinical use than S-SNPs and M-SNPs, as determined by lower observed toxicity and airway system inflammation.

Silica exposure and altered regulation of autoimmunity

Silica particles and asbestos fibers, which are known as typical causatives of pneumoconiosis, induce lung fibrosis. Moreover, silicosis patients often complicate with autoimmune diseases, and asbestos-exposed patients suffer from malignant diseases such as pleural mesothelioma and lung cancer. We have been conducting experimental studies to investigate altered regulation of self-tolerance caused by silica exposure, including analyses using specimens such as plasma and immunocompetent cells obtained from silicosis patients, as a means of examining the supposition that silica exposure induces molecular and cellular biological alterations of immune cells. These approaches have resulted in the detection of several specific autoantibodies, alterations of CD95/Fas and its related molecules, and evidence of chronic activation of responder T cells and regulatory T cells following silica exposure. In this review, we present details of our investigations as an introduction to scientific approaches examining the immunological effects of environmental and occupational substances.

Silicosis in India: past and present

PURPOSE OF REVIEW

This particular review focusses on the burden of the problem of silicosis and its clinical manifestations reported from India.

RECENT FINDINGS

In recent estimates from India, there are over 3 million workers exposed to silica dust, whilst 8.5 million more work in construction and building activities, similarly exposed to quartz. Several recent reports on lung function assessment show both restrictive and obstructive patterns. Tuberculosis is a common complication reported in Indian studies. Occasionally, silico-mycosis, lung cancer and connective tissue disorders in association with silicosis are also reported. The National Human Rights Commission (NHRC) in response to the direction from the Supreme Court of India has made several recommendations on preventive, remedial and rehabilitative measures. The NHRC has been asked to work with various stakeholders such as individual organizations, state and central governments and other agencies to implement the measures.

SUMMARY

Silicosis is a common occupational disorder seen all over India, particularly in the Central and Western States. It is an important cause of respiratory morbidity. The problem has been highlighted on the national level as a major human-rights concern in India.

Prevalence of connective tissue disease in silicosis (1985-2006)-a report from the state of Michigan surveillance system for silicosis

BACKGROUND

The risk of developing clinical connective tissue disease (CTD) has been reported to be increased among individuals with silica exposure.

METHODS

We reviewed the medical records of individuals reported to the Michigan Silicosis Surveillance system from 1985 to 2006 to confirm the diagnosis of silicosis and determine the presence of CTDs.

RESULTS

From 1985 to 2006, 1,022 cases were confirmed to have silicosis. Medical records of 790 cases were available. Thirty-three individuals had rheumatoid arthritis (RA) [prevalence 4.2% (prevalence ratio (RR) ranged from 2.26, 95% CI: 1.57-3.25 to 6.96, 95% CI: 2.93-16.53) depending on the reference rate used], two had scleroderma [prevalence 0.3% (RR 28.3, 95% CI: 6.09-129.98)], one had systemic lupus erythematosus [prevalence 0.1% (RR 2.53, 95% CI: 0.30-21.64)], two had Sjogrens syndrome [prevalence 0.3% (RR 0.42, 95% CI: 0.09-2.08)], and six had anti-neutrophil cytoplasm antibody (ANCA) vasculitis [prevalence 0.8% (RR 25.3, 95% CI: 6.34-101.04)]. There was no difference between those with and without CTD with respect to age, race, industry type, history of tuberculosis, application for workers' compensation, or severity of fibrotic changes on chest X-ray.

CONCLUSIONS

A two- to eightfold risk for RA and systemic lupus erythematosus, with a greater than 24-fold risk for scleroderma and ANCA vasculitis was found in individuals with silicosis. The most common CTD among silicotics in the Michigan disease registry was RA. Though not classically included in the category of CTD, ANCA-associated vasculitis was found to have a much greater prevalence amongst silicosis patients than the general population.