SESSION TITLE: Miscellaneous Global Case Reports
SESSION TYPE: Global Case Report
PRESENTED ON: Tuesday, October 28, 2014 at 01:30 PM - 02:30 PM
INTRODUCTION: IgG4-related disease (IgG4-RD) is characterized by lymphoplasmacytic tissue infiltration with a predominance of IgG4-positive plasma cells and T lymphocytes, usually accompanied by fibrosis, obliterative phlebitis, and elevated serum levels of IgG4. Modest tissue eosinophilia is also common. A good initial therapeutic response to glucocorticoids is characteristic, particularly if excessive tissue fibrosis has not supervened.
CASE PRESENTATION: We report a case of a 21years male with history of bronchial asthma in childhood and Hodgkin Lymphoma at the age of 6 years (received chemotherapy & recovered). He presented to us with history of dry cough, dyspnea on exertion, intermittent low grade fever, arthralgia & myalgia since 6 months. Reports were suggestive of consistent polycythemia and eosinophilia (absolute eosinophil count around 1700). All autoimmune and connective tissue markers were negative. His Immunoglobulin gamma globin electrophoresis was suggestive of elevated IgE & IgG4 levels (9.91g/dl). Cardiac function was compromised with an ejection fraction of 45%. HRCT showed calcified mediastinal lymph nodes. Histopathology of the EBUS-guided biopsy of the mediastinal lymph node showed lymphocytes, plasma cells, eosinophils & fibrin tissue. Immunohistochemical (IHC) for tonsillar tissue showed IgG4 positive plasma cells, while the test was negative for the mediastinal lymph node sample. On the basis of above clinical features and raised IgG4 levels we suspected IgG4-RD (most probably allergic pathogenesis).
DISCUSSION: The pathogenesis of IgG4-RD is poorly understood; findings consistent with an autoimmune disorder and an allergic disorder are present. The affected tissues share specific pathologic, serologic, and clinical features, regardless of the organ involved. The diagnosis of IgG4-RD is based upon biopsy findings demonstrating the characteristic histopathological findings and IHC staining. Serum IgG4 levels should be measured, and isolated elevated levels are a significant aid in diagnosis, although they are not diagnostic. The HP and IHC staining features of IgG4-RD are strikingly similar in different tissues, regardless of the organ or tissue involved. Most patients respond to glucocorticoids within several weeks, typically with symptomatic improvement, reductions in the size of masses or organ enlargement, improvement in organ function, and often a decrease in serum levels of IgG4. However, some require a few months to respond, and there are some patients who relapse and others who respond less well or not at all initially. Once a significant response is clinically evident in the affected organ system, we can gradually taper the dose of glucocorticoids, with a planned reduction over a two-month period, as tolerated, with the goal of discontinuing the medication. In patients who are resistant to glucocorticoids or who are unable to have their dose reduced sufficiently (usually to below 10 mg/day of prednisone) to avoid adverse effects of the medication due to chronic use, azathioprine (2 mg/kg/day) or mycophenolate mofetil (up to 2.5 g/day as tolerated) is used. However, the effects of these glucocorticoid-sparing medications in IgG4-RD have not been evaluated adequately to clearly define their role relative to other agents. B cell depletion therapy with rituximab is an effective treatment in many of the patients with disease that is refractory to glucocorticoids and other medications.
CONCLUSIONS: IgG4-RD is a rather uncommon condition which may be easily overlooked or diagnosed as something else if its possibility is not kept in mind. A thorough workup is essential to avoid misdiagnosis of IgG4-RD as asthma or sarcoidosis.
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Reference #2: The use of immunoglobulin g4 immunostaining in diagnosing pancreatic and extrapancreatic involvement in autoimmune pancreatitis. Deheragoda MG, Church NI. Clin Gastroenterol Hepatol. 2007;5(10):1229.
Reference #3: Autoimmune related pancreatitis.Okazaki K, Chiba T.Gut. 2002;51(1):1.
DISCLOSURE: The following authors have nothing to disclose: Miti Maniar, Fatima Mamnoon, Prahlad Prabhudesai, Abhijeet Khandelwal, Santosh Jha
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