Cortisol and ACTH Measurements at Extubation From Pituitary Surgery Predicts Hypothalamic-Pituitary-Adrenal Axis Function.

Context: Early prediction of hypothalamic-pituitary-adrenal (HPA) axis function following transsphenoidal surgery (TSS) can improve patient safety and reduce costs. Objective: Systematic measurement of ACTH and cortisol at extubation following anesthesia to predict remission from Cushing's disease (CD) and HPA axis preservation following non-CD surgery. Design: Retrospective analysis of clinical data between August 2015 and May 2022. Setting: Referral center. Patients: Consecutive patients (n = 129) undergoing TSS who had perioperative ACTH and cortisol measurements. Interventions: ACTH and cortisol measurement at extubation. Further serial 6-hourly measurements in CD patients. Main outcome measures: Prediction of future HPA axis status based on ACTH/cortisol at extubation. Results: ACTH and cortisol increased sharply in all patients at extubation. CD patients (n = 101) had lower ACTH values than non-CD patients (110.1 vs 293.1 pg/mL; P < 0.01). In non-CD patients, lower plasma ACTH at extubation predicted the need for eventual corticosteroid replacement (105.8 vs 449.1 pg/mL, P < 0.01). In CD patients, the peak post-extubation cortisol at 6 hours was a robust predictor for nonremission (60.7 vs 219.2 µg/dL, P = 0.03). However, normalized early postoperative value (NEPV; the post-extubation values minus the peak preoperative CRH or desmopressin test values) of cortisol reliably distinguished nonremission earlier, at the time of extubation (-6.1 vs 5.9, P = 0.01), and later. Conclusions: We found that at extubation following TSS, ACTH can predict the need for eventual steroid replacement in non-Cushing's patients. In patients with CD, we found a robust prediction of nonremission with NEPV cortisol at extubation and later.

Pituitary adenomas evade apoptosis via noxa deregulation in Cushing's disease.

Sporadic pituitary adenomas occur in over 10% of the population. Hormone-secreting adenomas, including those causing Cushing's disease (CD), cause severe morbidity and early mortality. Mechanistic studies of CD are hindered by a lack of in vitro models and control normal human pituitary glands. Here, we surgically annotate adenomas and adjacent normal glands in 25 of 34 patients. Using single-cell RNA sequencing (RNA-seq) analysis of 27594 cells, we identify CD adenoma transcriptomic signatures compared with adjacent normal cells, with validation by bulk RNA-seq, DNA methylation, qRT-PCR, and immunohistochemistry. CD adenoma cells include a subpopulation of proliferating, terminally differentiated corticotrophs. In CD adenomas, we find recurrent promoter hypomethylation and transcriptional upregulation of PMAIP1 (encoding pro-apoptotic BH3-only bcl-2 protein noxa) but paradoxical noxa downregulation. Using primary CD adenoma cell cultures and a corticotroph-enriched mouse cell line, we find that selective proteasomal inhibition with bortezomib stabilizes noxa and induces apoptosis, indicating its utility as an anti-tumor agent.

The progression of diversity: Black women in neurosurgery.

While diversity in organized medicine has undoubtedly improved, a disparity remains in the racial and gender makeup of its constituents. This disparity is not distributed equally among all specialties of practice. The surgical subspecialties exemplify this phenomenon by having large gaps between the number of women and racial/ethnic minorities compared to their majority counterparts. Pertaining to neurosurgery in the US, this gap is substantial, with women reaching minority status only within the last 2 years. Among international women in neurosurgery, Black women are even further underrepresented despite efforts in recent years to close the gender gap. The reason for this disparity is likely multifactorial, as Black women demonstrate a unique intersectionality as a minority in regard to both race and gender. In this study, the authors provide historical context for the current state of diversity in neurosurgery and the global strides made by Black women within the field. The authors report recurrent themes in the experiences of Black female neurosurgery attendings and residents as revealed through personal interviews. Furthermore, they examine factors that contribute to the disproportionate representation of Black women in neurosurgery.

Multiple VHL-related hemangioblastomas and holocord syrinx: identifying the causative lesion. Illustrative case.

BACKGROUND: Brainstem and spinal cord hemangioblastomas are a common manifestation of von Hippel-Lindau (VHL) disease. Cysts and associated syringes are the most common cause of significant morbidity in these patients. Surgical treatment of symptomatic hemangioblastomas are often complicated by the presence of multiple potential lesions, leading to cyst and syrinx formation. OBSERVATIONS: The authors present a case of a patient with multiple VHL-related hemangioblastomas who presented with syringobulbia and holocord syrinx. Resection of two cyst wall hemangioblastomas and one cervical hemangioblastoma only transiently improved syringobulbia. Eventual resolution of syringobulbia and collapse of the holocord syrinx only occurred following removal of a large lower thoracic hemangioblastoma. LESSONS: Surgical management of hemangioblastomas and associated cysts in patients with VHL should only target lesions most likely contributing to neurological deficits as excess surgical intervention risks treatment-related morbidity. The authors illustrate how anatomical and pathophysiological considerations as well as patient symptoms are key to identifying target lesions for resection and developing deliberate treatment plans.

Chronic inflammation and apoptosis propagate in ischemic cerebellum and heart of non-human primates.

The major pathological consequences of cerebral ischemia are characterized by neurological deficits commonly ascribed to the infarcted tissue and its surrounding region, however, brain areas, as well as peripheral organs, distal from the original injury may manifest as subtle disease sequelae that can increase the risks of co-morbidities complicating the disease symptoms. To evaluate the vulnerability of the cerebellum and the heart to secondary injuries in the late stage of transient global ischemia (TGI) model in non-human primates (NHP), brain and heart tissues were collected at six months post-TGI. Unbiased stereological analyses of immunostained tissues showed significant Purkinje cells loss in lobule III and lobule IX of the TGI cerebellum relative to sham cerebellum, with corresponding upregulation of inflammatory and apoptotic cells. Similarly, TGI hearts revealed significant activation of inflammatory and apoptotic cells relative to sham hearts. Aberrant inflammation and apoptosis in the cerebellum and the heart of chronic TGI-exposed NHPs suggest distal secondary injuries manifesting both centrally and peripherally. These results advance our understanding on the sustained propagation of chronic secondary injuries after TGI, highlighting the need to develop therapeutic interventions targeting the brain, as well as the heart, in order to abrogate cerebral ischemia and its related co-morbidities.