[Thymus hyperplasia: classification, problems of patho- and morphogenesis, importance in human pathology]. / Giperplaziia timusa: klassifikatsiia, voprosy pato- i morfogeneza, mesto v patologii cheloveka.

Thymus hyperplasia may be congenital (thymomegaly) and acquired (acquired thymomegaly, "tumour-like" hyperplasia, lymphofollicular hyperplasia). Congenital thymomegaly is represented by variants with hypo- and hyperfunction of an adequately formed thymus and results from the congenital neuro-endocrine disturbances. Thymomegaly with a thymus hypofunction is a marker of the immunodeficiency. Acquired thymomegaly is also represented by two variants with hypo- and hyper-function of the thymus and is in fact a "phenocopy" of the congenital one. "Tumor-like" thymus hyperplasia is a rare form of its pathology with a thymic weight reaching 800 g thus resulting in a syndrome of the mediastinum organs compression. Lymphofollicular thymus hyperplasia can not be always considered to be a thymus pathology but it is characteristic of autoimmune and infectious-allergic diseases with lymphoid follicles localizing in the hyperplastic intralobular perivascular spaces. Thymus parenchyma changes depend on the main disease and play a main role in the development of thymus dysfunction, for example, in the autoimmune diseases. Formation of lymphoid follicles in the dilated perivascular spaces is a non-specific process.

[New data on thymomegaly as a syndrome of congenital (primary) immunodeficiency]. / Novye dannye o timomegalii kak sindrome vrozhdennogo (pervichnogo) immunnogo defitsita.

Basing on a combined clinicomorphological investigation of the thymicolymphatic and neuroendocrine systems including measurements of blood thymic hormones and their levels in thymic tissue it is shown that congenital thymomegaly can be considered a dysfunction of the hypothalamo-hypophysial system. The dysfunction manifests with polyglandular endocrinopathy and congenital immunodeficiency related to the group of thymus-dependent immunodeficiencies. Thymomegaly is often coupled with congenital malformations.

[The pathogenesis of congenital thymus hyperplasia in children with immune defects]. / Zur Pathogenese der angeborenen Thymushyperplasie (ATH) bei Kindern mit Immundefekten.

Complex clinical and morphological studies were conducted into conditions of the thymus as well as of the lymphatic and neuro-endocrine systems in stillbirths and children up to five years of age. Thymic hormones in blood and thymic tissue were determined, as well. CTH, in most of these cases, was found to reflect dysfunction of the hypothalamic-hypophyseal system which eventually resulted in development of polyglandular endocrinopathy and congenital immune deficiency, primarily in the T-system. CTH has proved quite often to be associated with congenital malformations.

[The thymo-lymphatic system in congenital thymomegaly (clinico-morphological study)]. / Sostoianie timiko-limfaticheskoi sistemy pri vrozhdennoi timomegalii (kliniko-morfologicheskoe issledovanie).

To elucidate the functional capacity of the thymus and to evaluate immunity in congenital thymomegaly the authors studied 200 autopsy thymicolymphatic specimens obtained from children under 5 who had died from congenital malformations or acute respiratory diseases. The sections were studied histologically, histochemically and using immunofluorescence to detect thymalin and measure blood thymic hormones. The hormones secretion in congenitally thymomegaly was found reduced, the deficiency growing with the disease progression. Congenital thymomegaly is defined as a primary immunodeficiency of the T-cell immunity system predominantly, which demonstrates hypo- or dysfunction of the enlarged thymus combined with elevated proliferative activity and T-lymphocyte semimaturation.

Massive thymic hyperplasia in an infant with Beckwith-Wiedemann syndrome.

We report the clinical and postmortem findings in a newborn with Beckwith-Wiedemann syndrome and pulmonary hypoplasia. The infant was found to have a massively enlarged thymus gland that apparently caused pulmonary hypoplasia and respiratory insufficiency. Massive hyperplasia of the thymus gland should be considered in the differential diagnosis of respiratory distress in the Beckwith-Wiedemann syndrome.