Turner syndrome (TS), a disorder caused by the complete or partial absence of an X chromosome, exhibits significant clinical variability that cannot be fully explained by chromosomal anomalies alone. This narrative review highlights the crucial role of epigenetic mechanisms, particularly X-chromosome inactivation (XCI), in shaping the TS phenotype. The haploinsufficiency of genes that normally escape XCI is a primary driver of TS features. The specific epigenetic consequences depend on the chromosomal anomaly. In complete monosomy (45,X), the absence of escape-mediated dosage compensation genes from a second X chromosome amplifies haploinsufficiency across X-linked escape genes. Isochromosome Xq (i(Xq)) variants involve the loss of the short arm (Xp) and duplication of the long arm (Xq), creating a dual dosage imbalance with extreme XCI skewing. Carriers of i(Xq) also have a heightened risk for autoimmune disorders compared to those with 45,X TS. For ring-X chromosomes (r(X)), which are mitotically unstable, the functional status of the XIST gene is critical. If the ring is XIST-negative, it remains transcriptionally active, resulting in functional disomy and a more severe phenotype with pronounced neurodevelopmental and craniofacial features. Ultimately, the clinical heterogeneity in TS arises from a complex interplay of the specific chromosomal structure, tissue-specific mosaicism, XIST function, and variable escape from XCI, defining TS as a disorder of epigenetic and gene-regulatory imbalance. However, future research requires a better understanding of the complex mechanism of X-chromosome inactivation.

Acromegaly is a rare chronic endocrine disorder characterized by delayed diagnosis, multisystem comorbidity, and heterogeneous therapeutic response. We aimed to describe the clinical characteristics, tumor profile, treatment patterns, biochemical control, pituitary insufficiencies, and comorbidity burden in an endocrinology tertiary center in northeastern Romania. This observational retrospective study included 87 adult patients admitted for general inpatient evaluation between December 2023 and November 2024, with retrospective data collected from diagnosis and follow-up assessed through the last available hospital visit at St. Spiridon Clinical Emergency Hospital. Clinical, hormonal, imaging, and therapeutic data were analyzed using descriptive statistics and inferential statistical tests. Most patients were diagnosed in middle adulthood, with a female predominance. Macroadenomas and extrasellar extension were common, consistent with advanced tumor stage at presentation. Treatment was predominantly multimodal, with surgery as the main therapeutic intervention and somatostatin receptor ligands as the main medical treatment backbone. Biochemical improvement was observed over time, although complete remission was achieved only in a subset of patients. These findings describe the clinical and therapeutic complexity of acromegaly in a single tertiary-center inpatient cohort and support the need for individualized long-term monitoring.