Diagnosis and Treatment of Pituitary-Related Disorders

Pituitary apoplexy (PA) is a rare medical emergency. The sudden pressure increase in the sella turcica may determine compression on the surrounding structures determining the classical symptomatology associated, especially visual field impairment and/or ocular palsies and hypopituitarism; hypotonic hyponatremia may occur too, even if it is not common. Although already described in the literature, cases of isolated III cranial nerve palsies are extremely rare events. We report the case of a mid-60-year-old man with a known pituitary adenoma accessing the Emergency Department (ED) for worsening headaches unresponsive to analgesics, with a morphological picture consistent with ischemic PA, despite no dimensional increase of the pituitary lesion; upon ED access, a mild paucisymptomatic hyponatremia was also observed. Dexamethasone and mannitol were empirically introduced upon neurosurgical indication and tramadol and ketorolac were promptly administered as well, but without benefit. In the next days, a severe hypotonic hyponatremia was evidenced and a clear left III cranial nerve palsy developed, but no clear signs of cerebral bleeding or ischemia, nor a significant compression on the homolateral cavernous sinus, were observed. Upon ruling out other possible causes, a likely diagnosis of syndrome of inappropriate antidiuresis (SIAD) was made, confirmed by the quick response to fluid restriction. Overall, the sudden fall in tonicity plasma levels seemed to contribute to the exacerbation of the neurological deficit since the normalization of sodium levels was associated with a rapid and complete reversion of the III cranial nerve palsy. Full article

Secondary Adrenal Insufficiency (SAI) is a condition characterized by inappropriately low ACTH secretion due to a disease or injury to the hypothalamus or the pituitary. The evaluation when suspected is often challenging for the non-specific symptoms, the rarity of the disease, and the pitfalls associated with laboratory tests. A prompt and correct diagnosis of SAI is essential because although an adequate hormonal replacement therapy could be lifesaving, inappropriate life-long therapy with steroids can be harmful. The gold standard test for assessing the hypothalamus-pituitary-adrenal axis (HPA) is the insulin tolerance test (ITT), but due to safety issues is not widely used. Conversely, the ACTH stimulation test is a safer and well-tolerated tool for SAI diagnosis. However, data about its diagnostic accuracy show great variability due to both technical and interpretative aspects, such as dose, route of administration, the timing of the test, and assay used for cortisol measurements. Consequently, the clinical background of the patient and the pretest probability of HPA axis impairment become of paramount importance. We aimed to summarize the recent literature evidence in the conduction and interpretation of the ACTH stimulation test for the diagnosis of SAI to provide updated insights on its correct use in clinical practice. Full article

Background: Several studies have evaluated the role of IGF-1 in the diagnosis of growth hormone deficiency (GHD). According to a recent study, an IGF-1 concentration of a −1.5 standard deviation score (SDS) appeared to be the best cut-off for distinguishing between children with GHD and normal children. This value should always be interpreted in conjunction with other clinical and biochemical parameters for the diagnosis of GHD, since both stimulation tests and IGF-1 assays have poor diagnostic accuracy by themselves. Our study was designed to evaluate the adult height (AH) in children with short stature and baseline IGF-1 concentration ≤ −1.5 SDS. Design: This retrospective analysis included 52 children and adolescents evaluated over the last 30 years for short stature and/or deceleration of the growth rate who underwent diagnostic procedures to evaluate a possible GHD. Only the patients who had baseline IGF-1 values $\le$−1.5 SDS at the time of the first test were included in the study. Patients with genetic/organic GHD or underlying diseases were not included. Method: The case group consisted of 24 patients (13 boys and 11 girls) with non-permanent, idiopathic, and isolated GHD (peak GH < 10 μg/L after two provocative tests with arginine (Arg), insulin tolerance test (ITT), and clonidine (Clo), or <20 μg/L after GHRH + Arginine (GHRH+Arg); normal MRI; normal GH; and/or normal IGF-1 concentrations at near-AH). These patients were treated with GH (25–35 μg/kg/die) until near-AH. The control group consisted of 28 patients (23 boys and 5 girls) with idiopathic short stature (ISS, normal peak GH after provocative testing, no evidence of other causes for their shortness). Both groups had basal IGF-1 ≤−1.5 SDS. Results: AH and height gain in both groups were comparable. In the group of cases, mean IGF-1 SDS at the time of diagnosis was significantly lower than the levels found at the time of retesting. Conclusions: In this study, both treated patients with idiopathic GHD and untreated patients with ISS reached similar near-AHs (within target height) and showed similar increases in SDS for their height. Thus, the efficacy of treatment with rhGH in these patients may be questionable. This could be due to the fact that children with ISS are frequently misdiagnosed with GHD. Full article