Arginine Vasopressin Deficiency in Children with Craniopharyngioma and Cerebral Germ Cell Tumour: Two Sides of the Same Coin. Clinical and Radiological features.

INTRODUCTION: Paediatric brain tumours in the sellar-suprasellar region (SSR) are often associated with arginine vasopressin peptide deficiency (AVPD), either at diagnosis caused by the tumour itself or during follow-up as consequence of treatments. The purpose of this research is to retrospectively describe the neuroradiological characteristics and the timing of AVPD development in a cohort of paediatric patients with craniopharyngioma (CP) or germ cell tumours (GCT). METHODS: We evaluated brain MRI at tumour diagnosis and at the onset of AVPD, as well as recorded clinical, endocrinological and histopathological data, treatments, and outcome. RESULTS: Seventy-two patients with AVPD were included: 46 CP (M: F=25:21) and 26 GCT (M: F=18:8). CPs were suprasellar (63%), sellar (4%) or both (33%). GCTs were suprasellar (65%), pineal (24%) or bifocal (11%). No statistically significant differences were noted in tumour size between CP and GCT. Posterior pituitary bright spot absence was reported at diagnosis or at follow-up (as surgery consequence) in all patients with AVPD, indicating that the absence of hyperintensity is a cardinal feature of AVPD. When measurable, pituitary stalk was thickened in most GCT patients (61.5%). At AVPD diagnosis in GCT, the mean age was 11.9 years; 18 (69%) patients had AVPD at the time of tumour diagnosis, 5 (19.3%) before the diagnosis with a latency of 24.4 months (range 4-48), and 3 (11.5%) during follow-up (mean 24 months, range 4-60) due to tumour recurrence. GCT patients presented with severe endocrinological manifestations (18/26), headache and vomiting (10/26), visual impairment (5/26) and behavioural changes with fatigue (1/26). In CP, the mean age at AVPD diagnosis was 10.3 years; 7 (15.2%) patients had AVPD at time of tumour diagnosis, 37 (80.5%) developed it shortly after neurosurgery and 2 patients (4.3%) after 2 and 4 months from surgery, respectively. Clinically, headache and visual abnormalities were the most frequent clinical symptoms at diagnosis of CP (39/46, 84.8%), with hydrocephalus (16/46, 35%) and displacement of optic chiasm (29/46, 63%) at the initial MRI. While the vast majority of CP patients (93%) received only surgery, all GCT patients received radiation therapy in addition to or instead of surgery. CONCLUSION: An early differential diagnosis in children with AVPD and brain tumours is supported by a good understanding of the clinical features and imaging findings. Expert follow-up is necessary.

AVP deficiency (central diabetes insipidus) following immunization with anti-COVID-19 BNT162b2 Comirnaty vaccine in adolescents: A case report.

Introduction: The coronavirus disease 19 (COVID-19) pandemic has prompted the development of new vaccines to reduce the morbidity and mortality associated with this disease. Recognition and report of potential adverse effects of these novel vaccines (especially the urgent and life-threatening ones) is therefore essential. Case presentation: A 16-year-old boy presented to the Paediatric Emergency Department with polyuria, polydipsia and weight loss over the last four months. His past medical history was unremarkable. Onset of symptoms was referred to be few days after first dose of anti-COVID-19 BNT162b2 Comirnaty vaccine and then worsened after the second dose. The physical exam was normal, without neurological abnormalities. Auxological parameters were within normal limits. Daily fluid balance monitoring confirmed polyuria and polydipsia. Biochemistry laboratory analysis and urine culture were normal. Serum osmolality was 297 mOsm/Kg H2O (285-305), whereas urine osmolality was 80 mOsm/Kg H2O (100-1100), suggesting diabetes insipidus. Anterior pituitary function was preserved. Since parents refused to give consent to water deprivation test, treatment with Desmopressin was administered and confirmed ex juvantibus diagnosis of AVP deficiency (or central diabetes insipidus). Brain MRI revealed pituitary stalk thickening (4 mm) with contrast enhancement, and loss of posterior pituitary bright spot on T1 weighted imaging. Those signs were consistent with neuroinfundibulohypophysitis. Immunoglobulin levels were normal. Low doses of oral Desmopressin were sufficient to control patient's symptoms, normalizing serum and urinary osmolality values and daily fluid balance at discharge. Brain MRI after 2 months showed stable thicken pituitary stalk and still undetectable posterior pituitary. Due to persistence of polyuria and polydipsia, therapy with Desmopressin was adjusted by increasing dosage and number of daily administrations. Clinical and neuroradiological follow-up is still ongoing. Conclusion: Hypophysitis is a rare disorder characterized by lymphocytic, granulomatous, plasmacytic, or xanthomatous infiltration of the pituitary gland and stalk. Common manifestations are headache, hypopituitarism, and diabetes insipidus. To date, only time correlation between SARS-CoV-2 infection and development of hypophysitis and subsequent hypopituitarism has been reported. Further studies will be needed to deepen a possible causal link between anti-COVID-19 vaccine and AVP deficiency.

Implications of deferred diagnosis of paediatric intracranial germ cell tumours.

AIMS: This study analysed the clinical features of a cohort of children with intracranial germ cell tumours (IC-GCTs). We retrospectively reviewed timelag between symptoms onset, clinic-radiological findings, diagnosis and outcomes. METHODS: Symptoms at diagnosis were divided into four groups: (1) raised intracranial pressure (RICP); (2) visual impairment; (3) endocrinopathies; (4) other. Total diagnostic interval (TDI), defined as the interval between symptom onset (including retrospective recall of symptoms) and definitive diagnosis of IC-GCT, was calculated and compared to survival rates. RESULTS: Our cohort included 55 children with median follow-up of 78.9 months (0.5-249.9). The majority (63.6%) had germinomas and 10.9% were metastatic at diagnosis. IC-GCTs were suprasellar (41.8%), pineal (36.4%), bifocal (12.7%) or in atypical sites (9.1%). The most common presenting symptoms were related to RICP (43.6%); however, by the time of tumour diagnosis, 50.9% of patients had developed endocrine dysfunctions. All pineal GCTs manifested with RICP or visual impairment. All suprasellar GCTs presented with endocrinopathies. TDI ranged between 0.25 and 58.5 months (median 4 months). Pineal GCTs had the shortest TDI (median TDI 1 month versus 24 months in suprasellar GCTs, p < .001). TDI > 6 months was observed in 47.3% of patients and was significantly associated with endocrine presenting symptoms. No statistically significant difference was found in progression-free survival and overall survival between patients with TDI > 6 months and with TDI ≤ 6 months. CONCLUSION: Approximately half of the IC-GCT patients in this cohort had TDI > 6 months. These presented mostly with endocrine deficits. TDI > 6 months was not associated with increased relapse or mortality rates.

Sex steroid priming in short stature children unresponsive to GH stimulation tests: Why, who, when and how.

Despite decades of experience, the diagnosis of growth hormone deficiency (GHD) remains challenging, especially in peripubertal children. Failure to respond to GH stimulation tests (GHSTs) is needed to confirm GHD, but long-standing controversies regarding the number of tests needed and the interpretation of GH peaks are still a matter of debate worldwide. Diagnostic workup is even more problematic in short children with slow growth and delayed sexual development: they often exhibit low GH peaks under GHST, which often normalize as puberty progresses. Consequently, this transient suboptimal response to GHST may result in GH overtreatment, carrying both health and economic concerns. Considering the complex and bound link between GH axis and sex steroids, the use of sex steroid priming prior to GHST might be helpful in peripubertal setting. However, its use is still controversial. There is no consensus regarding patient selection, timing, dose, and preparation of sex steroids. In this review, we aim to overview the use of sex steroid priming in clinical practice, highlighting the need to develop appropriate guidelines in order to overcome diagnostic pitfalls in peripubertal age.

Endocrine manifestations of paediatric intracranial germ cell tumours: from diagnosis to long-term follow-up.

PURPOSE: We examined endocrine manifestations in a cohort of paediatric patients with IC-GCTs at diagnosis and during follow-up, integrating clinical, radiological, histopathological and laboratory data. METHODS: Diabetes insipidus (DI), growth hormone deficiency (GHD), hypothyroidism, adrenal insufficiency, precocious puberty (PP)/hypogonadism were diagnosed clinically and biochemically. The prevalence of endocrine manifestations was compared to survival rates. RESULTS: Our population included 55 children (37 males, 18 females) diagnosed with IC-GCT with a median follow-up of 78.9 months from diagnosis (range 0.5-249.9). At tumour diagnosis, 50.9% patients displayed endocrinopathies: among them, 85.7% were affected by DI, 57.1% central adrenal insufficiency, 50% central hypothyroidism, 28.5% GHD, 10.7% hypogonadotrophic hypogonadism, 10.7% PP. These patients presented predominantly with suprasellar germinoma. If not diagnosed previously, endocrine disorders arose 15.15 months (1.3-404.2) after end of treatment (EOT) in 16.4% patients. At least one endocrinopathy was identified in 67.3% of subjects at last follow-up visit, especially GHD and adrenal insufficiency. DI, hypothyroidism, and adrenal insufficiency occurred earlier than other abnormalities and frequently preceded tumour diagnosis. Subjects with and without endocrine manifestations who survived beyond 12 months after EOT did not show significant difference in overall survival and progression-free survival (p = 0.28 and p = 0.88, respectively). CONCLUSION: Endocrinopathies were common presenting symptoms in our population. If present at diagnosis, they often persisted hence after. The spectrum of endocrinopathies expanded during follow-up up to 33.7 years after EOT. Although they did not seem to affect survival rate in our cohort, close lifelong surveillance is mandatory to provide the best care for these patients.

Management of Childhood-onset Craniopharyngioma in Italy: A Multicenter, 7-Year Follow-up Study of 145 Patients.

CONTEXT: Nationwide data on children diagnosed with craniopharyngioma (CP) are not available in Italy. OBJECTIVE: This work aimed to identify patients' characteristics, type of surgical approach, complications and recurrences, number of pituitary deficits, and number of patients starting growth hormone (GH) treatment. METHODS: A retrospective multicenter collection took place of 145 patients aged 0 to 18 years who underwent surgery for CP between 2000 and 2018, and followed up in 17 Italian centers of pediatric endocrinology. RESULTS: Age at diagnosis was 8.4 ± 4.1 years. Duration of symptoms was 10.8 ± 12.5 months and headache was most frequent (54%), followed by impaired growth (48%) and visual disturbances (44%). Most lesions were suprasellar (85%), and histology was adamantinomatous in all cases but two. Surgical approach was transcranial (TC) in 67.5% of cases and transsphenoidal (TS) in 31.%. The TC approach was prevalent in all age groups. Postsurgery complications occurred in 53% of cases, with water-electrolyte disturbances most frequent. Radiotherapy was used in 39% of cases. All patients but one presented with at least one hormone pituitary deficiency, with thyrotropin deficiency most frequent (98.3%), followed by adrenocorticotropin (96.8%), arginine vasopressin (91.1%), and GH (77.4%). Body mass index (BMI) significantly increased over time. A hypothalamic disturbance was present in 55% of cases. GH therapy was started during follow-up in 112 patients at a mean age of 10.6 years, and 54 developed a recurrence or regrowth of the residual lesion. CONCLUSION: CP is often diagnosed late in Italy, with TC more frequent than the TS surgical approach. Postsurgery complications were not rare, and hypopituitarism developed almost in all cases. BMI shows a tendency to increase overtime.

Growth hormone therapy in children: predictive factors and short-term and long-term response criteria.

PURPOSE: The definition of growth response in growth hormone (GH)-treated children is controversial. This study aims at: (1) evaluating short-term and long-term efficacy of GH treatment in a cohort of short children with GH deficiency (GHD); (2) assessing and compare various poor response criteria; (3) identifying predictive factors of growth response. METHODS: Our study included 94 children, affected by isolated GHD and treated with GH until they reached final height. Criteria used for calculating the proportion of poor responders to GH for the first year were gain in height (ΔHt) SDS < 0.5 ("Bang criterion"), <0.3 or <0.4 SDS for less-severe and severe GHD, respectively ("Ranke criterion"), height velocity (HV) < mean -1 SDS ("Bakker criterion"); for adult height "Cianfarani criterion" was total ΔHt < 1 SDS. RESULTS: After 1 year of treatment we defined "poor responders" 55.3% of patients according to Bang criterion, 40.9% according to Bakker criterion and 23.4% according to Ranke criterion. At the end of the treatment, poor responders according to Cianfarani criterion were 22.34%; almost everyone in our population (97.9%) achieved mMid-parental height (MPH). Median final Ht was -1.11 SDS. Our analysis revealed a significant negative association between ΔHt and age at diagnosis. CONCLUSIONS: Bang criterion generated the highest number of poor responders, but had a low negative predictive value (67.5%); Ranke and Cianfarani criteria displayed similar rate of poor response. There is no reliable predictive factor of growth hormone response. However, almost all children treated reached MPH, suggesting good treatment efficacy.