Laboratory evaluation in rheumatic diseases

AChR-seropositive myasthenia gravis in muscular dystrophy: diagnostic pitfalls and clinical management challenges

The co-occurrence of genetic myopathies with myasthenia gravis (MG) is extremely rare, however a few studies have been reported. We aim to explore the link between genetically inherited muscle disorders and immune-mediated neuromuscular junction conditions, taking into account the diagnostic and therapeutic implications posed by these combined conditions. We searched all English medical papers registered in Web of Knowledge, PubMed, Google Scholar, and Science Direct between January 1987 concerning the association between muscular dystrophies (MD) and MG, also adding three new cases to the series reported so far. Three new clinical cases in which MG concurs with oculopharyngeal muscular dystrophy (OPMD) or facioscapulohumeral muscular dystrophy (FSHD) or myotonic dystrophy type 2 (DM2) were reported. A comprehensive literature review showed that FSHD is the dystrophy most frequently associated with generalized MG. The AChR antibody titer is high and neurophysiologic tests prove to be an essential tool for the diagnosis. The association between MG and MD is rare but should not be underestimated. The presence of unusual clinical features suggest investigating additional overlapping condition, especially when a treatable disease like MG is suspected.

Antinuclear Antibody Testing for the Diagnosis of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune inflammatory condition that may involve multiple organ systems. Although the antinuclear antibody (ANA) test is positive in nearly every case of SLE, it is not specific for this disease and must be interpreted in the appropriate clinical context. Key features that warrant ANA testing include unexplained multisystem inflammatory disease, symmetric joint pain with inflammatory features, photosensitive rash, and cytopenias. ANA staining patterns and more specific autoantibody testing may be helpful in diagnosis of suspected SLE or ANA-associated disease. For patients with nonspecific symptoms, such as malaise and fatigue, ANA testing is of limited value.

Antinuclear Antibody Testing for the Diagnosis of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune inflammatory condition that may involve multiple organ systems. Although the antinuclear antibody (ANA) test is positive in nearly every case of SLE, it is not specific for this disease and must be interpreted in the appropriate clinical context. Key features that warrant ANA testing include unexplained multisystem inflammatory disease, symmetric joint pain with inflammatory features, photosensitive rash, and cytopenias. ANA staining patterns and more specific autoantibody testing may be helpful in diagnosis of suspected SLE or ANA-associated disease. For patients with nonspecific symptoms, such as malaise and fatigue, ANA testing is of limited value.

Acute monoarthritis

Acute monoarthritis affects a single joint and has many potential underlying causes, including crystal deposition diseases, infection, trauma, and osteoarthritis. A comprehensive health history and physical examination can help narrow the list of differential diagnoses; judicious diagnostic testing can help pinpoint the diagnosis. Clinicians also must be able to recognize which patients require emergency referral to prevent long-term adverse consequences.

The Role of Long Non-coding RNAs in the Pathogenesis of RA, SLE, and SS

Rheumatoid diseases are a group of systemic autoimmune diseases which affect multiple organs with largely unknown etiology. In the past decade, long non-coding RNAs (lncRNAs) have emerged as important regulators of biological processes and contribute deeply to immune cell development and immune responses. Substantial evidences have been accumulated showing that LncRNAs involved in the pathogenesis of the rheumatoid diseases, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS). In this review, we summarize literature combined with bioinformatics methods to analyze the unique and common lncRNAs patterns in rheumatoid diseases and try to reveal the important function of lncRNAs in RA, SLE and SS.

Rheumatic Disease Autoantibodies in Patients with Autoimmune Thyroid Diseases

BACKGROUND

Patients with autoimmune thyroid diseases (ATD) such as Graves' disease (GD) and Hashimoto thyroiditis (HT) may have non-organ specific autoantibodies such as antinuclear antibodies (ANA) and rheumatoid factor (RF).

AIM

To study the prevalence of rheumatic autoantibodies in a group of ATD patients without known rheumatic diseases and to evaluate its association with the patients' epidemiological and treatment profiles. To follow positive non-organ specific autoantibody-positive ATD individuals to investigate whether they will develop a rheumatic disorder.

METHODS

A sample of 154 ATD patients (70 HT and 84 GD; mean age 45.3 ± 14.2) had determination of ANA by immunofluorescence, using hep-2 cells as substrate, extractable nuclear antigen profile by ELISA kits and RF by latex agglutination. Epidemiological and treatment profiles were obtained through chart review. These patients were followed for the mean period of 5 years, between 2010 and 2015.

RESULTS

Positive ANA was found in 17.5% (27/154) of the patients: anti-Ro/SS-A in 4/154 (2.5%); anti-RNP in 4/154 (2.5%), and anti-La/SS-B in 3/154 (1.9%). None had anti-Sm antibodies. RF was detected in 12/154 (7.7%) of ATD patients and was more common in older individuals (p = 0.007). There was a positive association between the presence of RF and ANA (p = 0.03; OR 3.89; 95% CI 1.1-13.3). None of the patients with positive autoantibodies developed clinical rheumatic diseases during the period of observation.

CONCLUSION

We found rheumatic autoantibodies in 17.5% of ATD patients without rheumatic diseases. None of them were associated with the appearance of clinical rheumatic disorder during the period of 5 years.