Diagnostic cytological features and differential diagnosis of subacute granulomatous (De Quervain's) thyroiditis

Abstract

Background: The aims of the study are to identify the diagnostic cytological features of subacute granulomatous thyroiditis (SGT), to compare our results with previous literature studies, and to investigate the cytological changes in SGT that mimic other thyroid lesions.Methods: This retrospective study was conducted with 69 cases. The cytology slides were re-evaluated. The diagnostic cytomorphological features of the disease were identified. The results were compared with the literature. Differential diagnosis of the disease is discussed with the results obtained. Results: The diagnostic cytological features consisted of lymphocytes, multinucleated giant cells, loose epithelioid histiocyte groups, granulomas, isolated epithelioid histiocytes, colloid, and neutrophil leukocytes. The highest degree of concordance between our results and the published literature was the presence of giant cells while the lowest was for microfollicles. Some reactive cytological features of SGT were similar to other benign or malignant diseases of the thyroid. Conclusion: SGT is a rare and self-limiting disease. Cytological features are not specific. The diagnosis should be confirmed by clinical and laboratory results. Reactive atypia in the early phase of the disease and microfollicles in the late phase may lead to a false cytological diagnosis, thus resulting in unnecessary resection. To prevent such misdiagnoses, cytopathologists should be aware of the reactive cytological changes in this disorder. K E Y W O R D S cytological features, De Quervain's, differential diagnosis, subacute granulomatous thyroiditis

Tirotoxicosis transitoria por tiroiditis subaguda (de Quervain): reporte de caso

“…Cuando se realizan, las descripciones ultrasonográficas son variables e incluyen áreas hipoecogénicas y heterogéneas, pobremente vascularizadas, con márgenes borrosos y sin calcificaciones; sin embargo, ninguno de estos hallazgos es patognomónico (11). También pueden aparecer lesiones nodulares que, ante la evaluación de radiólogos poco experimentados, pueden ser confundidas con hallazgos sugestivos de malignidad y llevar a la realización de procedimientos innecesarios como biopsias con aguja fina (8), las cuales suelen reportar hallazgos inespecíficos con linfocitos, células gigantes multinucleadas, inflamación mixta, granulomas y tejido granular necrótico (12). Otro estudio tampoco indicado de rutina, pero que es posible incluirlo en el abordaje diagnóstico, es la escintigrafía, en la cual se demuestra una captación reducida de yodo radioactivo, a diferencia de otras causas de tirotoxicosis como lo es la enfermedad de Graves (1).…”

Vaccine-Induced Subacute Thyroiditis (De Quervain’s) after mRNA Vaccine against SARS-CoV-2: A Case Report and Systematic Review

“…Subacute thyroiditis is caused by a T-cell-mediated hypersensitivity to viral antigens found in infected epithelial cells [ 8 ]. Diagnosis is usually performed by clinical features, laboratory findings, and ultrasound, whereas fine needle aspiration is reserved for selected cases to differentiate it from a thyroid neoplasm [ 5 ]. SARS-CoV-2 infection can act as a trigger for subacute thyroiditis [ 24 ], and a few cases of subacute thyroiditis were also reported after the SARS-CoV-2 vaccine [ 16 , 17 , 18 , 19 , 20 , 21 , 22 ], also referred to as ASIA syndrome [ 16 ].…”

“…The latter, also referred to as De Quervain’s thyroiditis, is the most common granulomatous disease of the thyroid and is typically found after a viral infection in middle-aged women. Disease course is benign, and the pathology is usually self-limited [ 5 ]. Signs and symptoms include cervical pain and increased inflammatory markers with onset usually two to eight weeks after a viral upper respiratory tract infection.…”

“…Several pathogens have been implicated in its pathogenesis, such as mumps virus, influenza virus, Epstein-Barr virus, coxsackievirus, adenovirus, echovirus, etc. [ 5 ]. A genetic correlation with human leukocyte antigen B-35 (HLA-B35) was also described [ 9 ].…”

Value of Quantitative Contrast-Enhanced Ultrasonography in Distinguishing Asymptomatic Subacute Thyroiditis from Papillary Thyroid Carcinoma

“…Pathological diagnosis was confirmed by a single pathologist with ten years of experience, who was blinded to the medical history and US findings of the patients. The pathological diagnosis was considered as a reference standard in this study (12,13).…”