ABSTRACT
Immunoglobulin G4-related disease (IgG4-RD) coexisting with clinically apparent autoimmune diseases, such as rheumatoid arthritis (RA) or antiphospholipid syndrome (APS), is a rarely documented combination in the scientific literature. In this case-based review, we present 2 intriguing cases with preexisting autoimmune diseases, namely, RA and primary APS, who exhibited coexistent IgG4- related lesions at unusual sites. The first case pertains to a patient with known RA who presented with an encasing mass in the esophagus leading to stricture, with histopathological diagnosis of IgG4-RD.The second patient, diagnosed with primary APS, experienced breathlessness, and imaging revealed a right atrial mass. Histopathological examination of the mass confirmed IgG4-RD. Notably, both patients demonstrated significant clinical improvement upon initiation of steroid therapy. Rheumatoid arthritis patients commonly exhibit elevated levels of IgG4 in their sera; however, RA with coexisting IgG4-RD is rarely reported in the literature. Similarly, APS with IgG4-related lesions is exceedingly rare. Although there are few case reports and series on esophageal and cardiac IgG4-RD, the occurrence of such unusual location of IgG4-related lesions in the context of known autoimmunity is presented here for the first time.
ABSTRACT
OBJECTIVES: Dysregulation of interferon-alpha (IFN-α) is considered central to the immunological abnormalities observed in SLE. Short-term mortality during high disease activity in lupus is up to 30%. Adenovirus vector-introduced IFN-α into a lupus-prone mouse causes the development of glomerulonephritis and death within weeks. We studied serum IFN-α as a biomarker of in-hospital mortality in patients of SLE with high disease activity. METHODS: Serum IFN-α (ELISA) was measured in patients hospitalised for acute severe lupus in a tertiary care rheumatology unit in India and the levels were compared between survivors and non-survivors. Serum IFN-α was compared with traditional clinical and serological markers associated with disease activity to assess which better prognosticates survival. RESULTS: In a cohort of 90 patients with a mean Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) of 19.3 (±5.5), the mean serum IFN-α was 88±144 pg/dL. Levels were undetectable in patients with inactive disease. SLEDAI, anti double stranded DNA (dsDNA) antibody titres and serum IFN-α levels were higher and serum complement (C3) lower in non-survivors (p=0.003, p=0.017, p<0.001, p=0.029, respectively). Serum IFN-α level of 140 pg/mL had a sensitivity of 86.7%, specificity of 94.6%, positive predictive value of 76% and negative predictive value of 83.3% (p<0.001) in predicting mortality. The area under the curve for predicting in-hospital mortality was 0.25 for C3, 0.72 for dsDNA, 0.77 for SLEDAI and 0.92 for serum IFN-α. CONCLUSIONS: Serum IFN-α was better in predicting in-hospital mortality compared with conventional measures of disease activity such as anti-dsDNA, complements and SLEDAI.
