Autoimmune pancreatitis: An underdiagnosed autoimmune disease with clinical, imaging and serological features

The Presence of Serum TgAb Suggests Lower Risks for Glucose and Lipid Metabolic Disorders in Euthyroid General Population From a National Survey

Purpose: The expressions of antibodies against thyroid peroxidase (TPOAb) and thyroglobulin (TgAb) are very common in the sera of patients with autoimmune thyroid diseases (AITD). The relationship between thyroid autoantibodies and the occurrence of glucose and lipid metabolic disorders remains unclear. This study was performed to investigate the correlation between the presence of serum TPOAb/TgAb and those metabolic disorders in euthyroid general population. Methods: The data of this study were derived from the Thyroid Disease, Iodine status, and Diabetes National epidemiological (TIDE) survey from all 31 provinces of mainland China. A total of 17,964 euthyroid subjects including 5,802 males (4,000 with TPOAb^-TgAb^- and 1,802 with TPOAb⁺/TgAb⁺) and 12,162 females (8,000 with TPOAb^-TgAb^- and 4,162 with TPOAb⁺/TgAb⁺) were enrolled in this study. The blood glucose and lipid levels were compared between individuals with TPOAb^-TgAb^- and those with TPOAb⁺TgAb^-, TPOAb^-TgAb⁺, TPOAb⁺TgAb⁺. Results: Both fasting blood glucose (FBG) concentration and the proportion of individuals with impaired FBG (IFG) showed the decreased trends in TPOAb^-TgAb⁺ males as compared with TPOAb^-TgAb^- men. There were significantly lower FBG and higher HDL-C levels as well as tendencies toward decreased incidences of IGT and hypertriglyceridemia in TPOAb^-TgAb⁺ females when compared with TPOAb^-TgAb^- women. Binary logistic regression analysis further showed that serum TgAb single positivity in males was an independent protective factor for IFG with an OR of 0.691 (95% CI, 0.503-0.949). For females, serum TgAb single positivity was an independent protective factor for hypertriglyceridemia with an OR of 0.859 (95% CI, 0.748-0.987). Trend test showed that with the increase of serum TgAb level, there were significant decreases in the prevalence of IFG among the men with TSH ≤ 2.5 mIU/L and that of hypertriglyceridemia in the women, especially among non-obese females. Conclusion: Serum TgAb single positivity may imply a reduced risk of IFG in euthyroid men and that of hypertriglyceridemia in euthyroid women. The mechanisms for the independent protective roles of TgAb await further investigation.

Pancreatitis after human papillomavirus vaccination: a matter of molecular mimicry

A 20-year-old man developed severe abdominal pain 1 week after being vaccinated with the first dose of quadrivalent human papillomavirus (HPV) vaccine (Gardasil^®). Despite ongoing symptoms of nausea and pain, he received the second dose of the vaccine. Only 10 days later, laboratory results revealed significantly elevated pancreatic enzymes, and with concomitant abdominal pain and vomiting, he was diagnosed with acute pancreatitis. This case of acute pancreatitis after HPV vaccination is not a novel entity. Although confirming the relationship between pancreatitis and vaccine is challenging, some factors suggest a possible link, including the positive re-challenge upon repeated exposure to the vaccine, HPV vaccine as probable causal relationship to other autoimmune diseases and a probable mechanism of molecular mimicry. In conjunction with aluminum adjuvant, the induction of immunity through molecular mimicry may potentially culminate in production of cytotoxic autoantibodies with a particular affinity for pancreatic acinar cells.

The changing faces of IgG4-related disease: Clinical manifestations and pathogenesis

Since the earliest reports in 2001, immunoglobulin G4 (IgG4)-related disease has been defined as an autoimmune systemic disease characterized by the lymphoplasmacytic infiltration of affected tissues leading to fibrosis and obliterative phlebitis along with elevated serum IgG4 levels. Prior to this unifying hypothesis, a plethora of clinical manifestations were considered as separate entities despite the similar laboratory profile. The pathology can be observed in virtually all organs and may thus be a challenging diagnosis, especially when the adequate clinical suspicion is not present or when obtaining a tissue biopsy is not feasible. Nonetheless, the most frequently involved organs are the pancreas and exocrine glands but these may be spared. Immunosuppressants lead to a prompt clinical response in virtually all cases and prevent histological sequelae and, as a consequence, an early differential diagnosis from other conditions, particularly infections and cancer, as well as an early treatment should be pursued. We describe herein two cases in which atypical disease manifestations were observed, i.e., one with recurrent neck lymph node enlargement and proptosis, and one with jaundice. Our understanding of the pathogenesis of IgG4-related disease is largely incomplete but data support a significant role for Th2 cytokines with the contribution of innate immunity factors such as Toll-like receptors, macrophages and basophils. Further, macrophages activated by IL4 overexpress B cell activating factors and contribute to chronic inflammation and the development of fibrosis. We cannot rule out the possibility that the largely variable disease phenotypes reflect different pathogenetic mechanisms and the tissue microenvironment may then contribute to the organ involvement.

Autoimmune pancreatitis: whole-body 18F-FDG PET/CT findings

PURPOSE

The study aimed to investigate the function of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in diagnosing of autoimmune pancreatitis (AIP) and whole-body evaluation.

METHODS

Seven AIP patients who underwent (18)F-FDG PET/CT systemic examination in our hospital from August 2010 to March 2012 were analyzed retrospectively. Systemic PET/CT routine scanning and pancreatic delayed scanning were performed in all patients.

RESULTS

The mean age of 7 AIP patients (6 male and 1 female) was 54.2 years (range from 42 to 71 years). The pancreas showed diffuse enlargement in 6 cases, and segmental enlargement in 1 case. Fluorodeoxyglucose (FDG) uptake was increased in diseased region. The maximum standardized uptake value (SUVmax) was 4.38 ± 0.90 and increased to 5.31 ± 1.08 after delayed scanning, of which small amounts of inflammatory exudate around pancreas was observed in 4 cases. Extrapancreatic lesions (EPLs) were observed in all 7 cases: lymphadenectasis (n = 5), lymphadenectasis with increased FDG uptake (n = 4); associated sialosis with metabolism enlargement (n = 4); associated cholangitis (n = 4); associated interstitial pneumonia (n = 3); inverted "V" shaped high FDG uptake foci in prostate (n = 5).

CONCLUSIONS

AIP is a systemic disease. (18)F-FDG PET/CT can exhibit the characteristics of AIP pancreatic lesions, and also better reflect the changes and metabolic characteristics of extrapancreatic organs. It plays a distinct role in diagnosis, differentiating of AIP and whole-body evaluation.

Serum anti-carbonic anhydrase antibodies and oxidant-antioxidant balance in patients with acute anterior uveitis

PURPOSE

To study the existence of anti-carbonic anhydrase antibodies (anti-CA-I&II) in acute anterior uveitis (AAU) patients and to analyze the relationship between the levels of these antibodies and the total antioxidant capacity (TAC), total oxidant capacity (TOC), oxidative stress index (OSI), and malondialdehyde (MDA) level.

METHODS

Forty-five AAU cases and 43 healthy controls were enrolled in this prospective study.

RESULTS

The average anti-CA I and II antibody levels were 0.433 ± 0.306 and 0.358 ± 0.261 IU/mL, respectively, in the AAU group and 0.275 ± 0.147 and 0.268 ± 0.108 IU/mL, respectively, in the control group (p = 0.004 and p = 0.036, respectively). In addition, it was found that the TOC, OSI, and MDA levels in the AAU subjects were statistically significantly higher than those of the control subjects.

CONCLUSIONS

These results suggest that autoimmune responses against CA I and CA II and an altered serum oxidant-antioxidant balance may be involved in the pathogenesis of AAU.

Is autoimmune diabetes caused by aberrant immune activity or defective suppression of physiological self-reactivity?

Two competing hypotheses are proposed to cause autoimmunity: evasion of a sporadic self-reactive clone from immune surveillance and ineffective suppression of autoreactive clones that arise physiologically. We question the relevance of these hypotheses to the study of type 1 diabetes, where autoreactivity may accompany the cycles of physiological adjustment of β-cell mass to body weight and nutrition. Experimental evidence presents variable and conflicting data concerning the activities of both effector and regulatory T cells, arguing in favor and against: quantitative dominance and deficit, aberrant reactivity and expansion, sensitivity to negative regulation and apoptosis. The presence of autoantibodies in umbilical cord blood of healthy subjects and low incidence of the disease following early induction suggest that suppression of self-reactivity is the major determinant factor.

Carbonic anhydrases III and IV autoantibodies in rheumatoid arthritis, systemic lupus erythematosus, diabetes, hypertensive renal disease, and heart failure

In the present study, the CA III and IV autoantibodies, CA activity, antioxidant enzymes and cytokines in rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), diabetes, hypertensive renal disease, and heart failure were investigated. The anti-CA III antibody titers in patients with RA, SLE, and type 1 diabetes (T1D) were significantly higher than that in control groups (P < 0.05). The anti-CA IV antibody titers in patients with RA, SLE, type 1 diabetic nephropathy (T1DN), and heart failure were significantly higher than that in control groups (P < 0.05) while anti-CA IV antibody could suppress the total CA activity. The SOD and GPx levels in patients with RA, SLE, and T1DN were significantly lower than that in control groups (P < 0.05). IL-6, IL-17, IFN-γ, and TNF-α levels were significantly higher in SLE group compared with the control group (P < 0.05). Weak but significant correlations were found between anti-CA III antibodies and ESR in RA (r = 0.403, P = 0.013) and SLE patients (r = 0.397, P = 0.007). These results suggested that the generation of CA III and IV autoantibodies, antioxidant enzymes, and cytokines might influence each other and CA autoantibodies might affect the normal physiology function of CA.

Nonalcoholic, nonbiliary pancreatitis: cross-sectional imaging spectrum

OBJECTIVE

The purpose of this review is to describe the epidemiologic, etiopathogenetic, clinical, and imaging characteristics of various nonalcoholic, nonbiliary pancreatitis syndromes.

CONCLUSION

The spectrum of nonalcoholic, nonbiliary pancreatitis includes autoimmune pancreatitis, groove pancreatitis, hereditary pancreatitis, tropical pancreatitis, tuberculous pancreatitis, and metabolic pancreatitis. Advances in genetics and molecular pathology have shed new light on the etiopathogenesis and course of these syndromes. Accurate diagnosis aided by imaging findings allows optimal management.