Lymphoid thymic hyperplasia, also referred to as lymphoid follicular thymic hyperplasia or autoimmune thymitis, is a form of thymic hyperplasia.
Unlike in true thymic hyperplasia, there is a presence of an increased number of lymphoid follicles.
This condition is most commonly associated with conditions, such as:
- autoimmune conditions
- myasthenia gravis: may be seen in up to 65% of cases
- immunologically mediated disorders
Some publications (with small sample sizes) suggest that CT attenuation of lymphoid hyperplasia can be significantly higher than that of true hyperplasia, with the optimal threshold of around 40 HU useful for differentiating lymphoid hyperplasia from true thymic hyperplasia 3.
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