Inflammatory and Infectious Disorders in Endocrine Pathology

A variety of inflammatory conditions may directly involve the endocrine glands, leading to endocrine dysfunction that can cause severe consequences on patients' health, if left untreated. Inflammation of the endocrine system may be caused by either infectious agents or other mechanisms, including autoimmune and other immune-mediated processes. Not infrequently, inflammatory and infectious diseases may appear as tumor-like lesions of endocrine organs and simulate neoplastic processes. These diseases may be clinically under-recognized and not infrequently the diagnosis is suggested on pathological samples. Thus, the pathologist should be aware of the basic principles of their pathogenesis, as well as of their morphological features, clinicopathological correlates, and differential diagnosis. Interestingly, several systemic inflammatory conditions show a peculiar tropism to the endocrine system as a whole. In turn, organ-specific inflammatory disorders are observed in endocrine glands. This review will focus on the morphological aspects and clinicopathological features of infectious diseases, autoimmune disorders, drug-induced inflammatory reactions, IgG4-related disease, and other inflammatory disorders involving the endocrine system. A mixed entity-based and organ-based approach will be used, with the aim to provide the practicing pathologist with a comprehensive and practical guide to the diagnosis of infectious and inflammatory disorders of the endocrine system.

Autoimmune polyendocrine syndrome II presenting paradoxically as Takotsubo cardiomyopathy: a case report and reappraisal of pathophysiology

BACKGROUND

Takotsubo cardiomyopathy (TCM) is a rare disease entity characterized by acute, non-ischemic, reversible myocardial dysfunction that mimics acute myocardial infarction. Activation and excessive outflow of sympathetic nervous system are believed to be central to the figure in the disease pathogenesis. Adrenocortical hormones potentiate the systemic actions of sympathetic nervous system and accordingly are essential for regulation of myocardial function. We present an unusual case of a middle-aged woman with primary adrenal insufficiency who presented paradoxically with TCM.

CASE PRESENTATION

A 50-year-old woman with past history of hypothyroidism presented to emergency department with history of acute chest pain and syncope. There was no significant drug history or history of an emotional or physical stimulus prior to admission. Prominent pigmentation over the tongue and skin creases of hands were noted. On presentation, she was in shock and had ventricular tachycardia which required electrical cardioversion. The subsequent electrocardiogram demonstrated diffuse T-wave inversions with prolonged QT_C. There was apical hypokinesia on echocardiogram, and cardiac biomarkers were elevated. There was persistent inotropic requirement. She had marked postural symptoms, and a postural blood pressure drop of 50 mm Hg was present. Initial laboratory parameters were significant for hyperkalemia (7.8 mEq/L) and hyponatremia (128 mEq/L). These findings prompted evaluation for adrenal insufficiency which was confirmed with appropriate tests. Autoimmune polyendocrine syndrome II was thus diagnosed based on the above findings. Coronary angiography revealed normal coronaries. The diagnoses of TCM was established in accordance with the International Takotsubo Diagnostic Criteria. She was started on stress dose steroid replacement therapy and improved dramatically. At one month of follow-up, the patient is asymptomatic, and there was normalization of her left ventricular function.

CONCLUSIONS

Intricate relationship and interplay exist between the steroid hormones and catecholamines in the pathogenesis of TCM. Steroid hormones not only potentiate the actions of catecholamines, but they also regulate and channelize catecholaminergic actions preventing their deleterious effects on the cardiac tissue. Hence, both steroid deficiency and exogenous steroid replacement may precipitate TCM. Evidence from more such cases and larger perspective studies in future will further improve our understanding of this complex disease process and its myriad associations.

[The efficacy of alemtuzumab for pure red cell aplasia associated with autoimmune polyendocrine syndrome type 1]

We present a case of a 41-year-old woman who was diagnosed with autoimmune polyendocrine syndrome type 1 (APS-1) at the age of 2. She developed severe anemia and was diagnosed with pure red cell aplasia (PRCA) and T-cell large granular lymphocyte leukemia at the age of 34. The pathogenesis of APS-1 is based on the presence of an inactive mutation in the autoimmune regulator gene on thymic medullary epithelial cells. It is thought that the autoimmune T cells generated by impaired negative selection in the thymus induce PRCA. The patient was treated with immunosuppressive therapy (ciclosporin, antithymocyte globulin, prednisolone, and cyclophosphamide) for a long time by her previous doctor. After a long period of remission and exacerbation, she became dependent on blood transfusion approximately at the age of 40 and was transferred to our hospital. At our hospital, alemtuzumab treatment resulted in the disappearance of large granular lymphocytes and improvement of anemia. We report this case as a valuable demonstration of the efficacy of alemtuzumab for treating PRCA associated with APS-1.

Autoimmune polyendocrine syndrome induced by immune checkpoint inhibitors: a systematic review

OBJECTIVE

To summarize the clinical characteristics and immunological and genetic features of patients who developed autoimmune polyendocrine syndrome type II (APS-2) after treatment with immune checkpoint inhibitors (ICIs).

DESIGN AND METHODS

Several databases (MEDLINE/EMBASE/Cochrane) were searched for studies published between January 2000 and February 2020 involving patients with two or more endocrine disorders after ICI therapy.

RESULTS

Our final review included 22 articles comprising 23 patients (median age 56 years; 65.2% male patients). Of these patients, 60.9% received anti-programmed cell death 1 (PD-1) therapy, 17.4% received anti-programmed cell death ligand 1 (PD-L1) therapy, and 4.3% received anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) monotherapy. Patients underwent a median of four treatment cycles before the onset of the primary adverse event; the median time of onset was 8.5 weeks. Endocrine organs affected by ICI administration included the thyroid gland (18/23, 78.3%), pancreatic islets (17/23, 73.9%), pituitary gland (11/23, 47.8%), and adrenal gland (2/23, 8.7%). Related autoantibodies were detected in 65.2% of patients. In patients with diabetes, glutamic acid decarboxylase antibody was closely related to the development of diabetes ketoacidosis. The human leukocyte antigen genotype was reported in 34.8% (8/23) of patients, 5 (62.5%) of which had risk genotypes.

CONCLUSIONS

As a serious adverse event of ICI treatment, APS-2 is presented with abrupt initiation time and rapid development. Physicians should be aware of potential endocrine disorders and continue monitoring hormone status when treating cancer patients with ICIs.

A case of eosinophilic esophagitis with autoimmune polyendocrine syndrome type 2, including autoimmune gastritis

Both eosinophilic esophagitis (EoE) and autoimmune polyendocrine syndrome (APS) are relatively rare diseases in Japan. We herein report a case of EoE with APS in a 67-year-old Japanese man who presented with chest pain and dysphagia. On the basis of endoscopic findings and histological analysis, we diagnosed the patient with EoE along with autoimmune gastritis. Additional serological examinations revealed the presence of Hashimoto's thyroiditis and type 1 diabetes, which led to the final diagnosis of APS. His symptoms did not respond to treatment with a proton-pump inhibitor but improved with topical steroid therapy. This case of coexisting EoE and APS-2 is quite rare and has several implications for the pathogenesis of both conditions.

Autoimmune Polyendocrine Syndrome Complicated by Pulmonary Hypertension

A 24-years old female was admitted for acute renal failure, melanoderma, hyponatremia, and hyperkalemia. The clinical suspicion of Addison's disease was confirmed by laboratory test and the appropriate replacement therapy with corticosteroids and fludrocortisone was started. In the meantime primary hypothyroidism and diabetes mellitus type 1 were disclosed and treated, thus fulfilling a diagnosis of autoimmune polyendocrine syndrome type 2. Eighteen months later she was admitted for right-sided heart failure. The work-up allowed to diagnose pulmonary arterial hypertension. Here, we report the clinical course and discuss the putative link between these two rare diseases.

Compromised central tolerance of ICA69 induces multiple organ autoimmunity

For reasons not fully understood, patients with an organ-specific autoimmune disease have increased risks of developing autoimmune responses against other organs/tissues. We identified ICA69, a known β-cell autoantigen in Type 1 diabetes, as a potential common target in multi-organ autoimmunity. NOD mice immunized with ICA69 polypeptides exhibited exacerbated inflammation not only in the islets, but also in the salivary glands. To further investigate ICA69 autoimmunity, two genetically modified mouse lines were generated to modulate thymic ICA69 expression: the heterozygous ICA69(del/wt) line and the thymic medullary epithelial cell-specific deletion Aire-ΔICA69 line. Suboptimal central negative selection of ICA69-reactive T-cells was observed in both lines. Aire-ΔICA69 mice spontaneously developed coincident autoimmune responses to the pancreas, the salivary glands, the thyroid, and the stomach. Our findings establish a direct link between compromised thymic ICA69 expression and autoimmunity against multiple ICA69-expressing organs, and identify a potential novel mechanism for the development of multi-organ autoimmune diseases.