Clinical and Biochemical Correlation With Cytomorphological Findings of Lymphocytic Thyroiditis: An Experience at a Tertiary Centre in the Himalayan Foothills.

Introduction Lymphocytic thyroiditis is an autoimmune disorder and one of the major causes of hypothyroidism. On cytomorphology, it is characterized by follicular destruction by lymphocytes with elevated biochemical markers, including a panel of autoantibodies against thyroid antigens. This study aimed to determine the prevalence of various cytological features of lymphocytic thyroiditis and their correlation with clinical presentation and biochemical parameters. Materials and methods We conducted a hospital-based cross-sectional study of 105 patients diagnosed with lymphocytic thyroiditis on cytology at our tertiary care center in the Himalayan foothills from December 2018 to December 2019. We recorded and analyzed baseline demographic characteristics, clinical features, and biochemical parameters to assess correlations between cytological findings and grades. Results The study included 105 patients with lymphocytic thyroiditis (90 females, 15 males). The study population age ranged from 11 years to 80 years, with the disease most common in patients aged 21 to 40 years. Grade II was the most common cytological presentation (n=65, 62%). Thyroid-stimulating hormone levels were elevated in 33.3% of cases, and anti-thyroid peroxidase levels were elevated in all 25 cases for whom data were available (p>0.05). Conclusion Cytological diagnosis of lymphocytic thyroiditis was compatible in all cases in the study. However, cytological grading did not correlate with the clinical presentation and biochemical parameters. The diagnosis of lymphocytic thyroiditis could be missed if clinicians use clinical findings and biochemical parameters alone.