Summary & Overview
Diseases of thymus: ICD-10-CM Diagnosis Code Group Overview
International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) codes under the group ICD-10-CM E32 cover disorders of the thymus such as thymic hyperplasia, thymic tumors, and other specified thymic conditions that affect immune and endocrine function. Accurate ICD-10-CM coding for this group is important for appropriate reimbursement, care coordination, and accurate health records.
Diseases of thymus Overview
The diagnoses in this group represent disorders of the thymus gland, including thymic hyperplasia, thymic neoplasms, and other noninflammatory conditions affecting thymic structure and function. These conditions target the endocrine and lymphoid components of the anterior mediastinum and can impact immune regulation and systemic health. Accurate coding ensures correct clinical classification and supports appropriate reimbursement and reporting for services related to diagnosis, imaging, and treatment.
Typical Clinical Scenarios
- An adult presents to the emergency department with acute onset chest pain, cough, and dyspnea; imaging (chest CT) reveals an enlarged anterior mediastinal mass consistent with thymoma causing compressive symptoms and possible local invasion. Tissue biopsy confirms a thymic epithelial tumor and the encounter is for initial evaluation and management of the thymic neoplasm, so a code for thymoma is assigned. Typical codes:
E321 - A middle-aged patient with long-standing myasthenia gravis attends a neurology clinic for routine follow-up; serial imaging shows a stable, noninvasive thymic hyperplasia identified as the likely underlying thymic disorder. The visit documents chronic thymic enlargement as part of the patient’s comorbid autoimmune condition and is coded accordingly. Typical codes:
E320 - An older adult is admitted with progressive respiratory failure due to metastatic thymic carcinoma identified on prior workup; the hospitalization focuses on complications from the malignant thymic disease including pleural effusion and paraneoplastic syndromes. Because the encounter centers on the malignant process of the thymus and its complications, a thymic malignancy code from this group is used. Typical codes:
E329,E321