Central Diabetes Insipidus Caused by Arginine Vasopressin Gene Mutation: Report of a Novel Mutation and Review of Literature.

Familial neurohypophyseal diabetes insipidus (FNDI) is an autosomal dominant hereditary disorder characterized by severe polydipsia and polyuria that usually presents in early childhood. In this study, we describe a new arginine vasopressin (AVP) gene mutation in an ethnic German family with FNDI and provide an overview of disease-associated AVP-gene mutations that are already described in literature. Three members of a German family with neurohypophyseal diabetes insipidus were studied. Isolated DNA from peripheral blood samples was used for mutation analysis by sequencing the whole coding region of AVP-NPII gene. Furthermore, we searched the electronic databases MEDLINE (Pubmed) as well as HGMD, LOVD-ClinVar, db-SNP and genomAD in order to compare our cases to that of other patients with FNDI. Genetic analysis of the patients revealed a novel heterozygote missense mutation in exon 2 of the AVP gene (c.274T>G), which has not yet been described in literature. We identified reports of more than 90 disease-associated mutations in the AVP gene in literature. The novel mutation of the AVP gene seems to cause FNDI in the presented German family. Similar to our newly detected mutation, most mutations causing FNDI are found in exon 2 of the AVP gene coding for neurophysin II. Clinically, it is important to think of FNDI in young children presenting with polydipsia and polyuria.

A novel mechanism of autophagy-associated cell death of vasopressin neurons in familial neurohypophysial diabetes insipidus.

Familial neurohypophysial diabetes insipidus (FNDI), characterized by delayed-onset progressive polyuria and loss of arginine vasopressin (AVP) neuron, is an autosomal dominant disorder caused by AVP gene mutations. We previously generated a knock-in mouse model for FNDI, which recapitulated the phenotype of human FNDI. To address the mechanisms underlying AVP neuron loss, we subjected FNDI mice to intermittent water deprivation, which accelerated the phenotype and induced AVP neuron loss within a relative short period. Electron microscopic analyses revealed that aggregates were confined to a sub-compartment of the endoplasmic reticulum (ER), ER-associated compartment (ERAC), in AVP neurons of FNDI mice under normal conditions. In contrast, aggregates scattered throughout the dilated ER lumen, and phagophores, autophagosome precursors, emerged and surrounded the ER containing scattered aggregates in FNDI mice subjected to water deprivation for 4 weeks, suggesting that failure of ERAC formation leads to autophagy induction for degradation of aggregates. Furthermore, the cytoplasm was entirely occupied with large vacuoles in AVP neurons of FNDI mice subjected to water deprivation for 12 weeks, at which stage 30-40% of AVP neurons were lost. Our data demonstrated that although autophagy should primarily be a protective mechanism, continuous autophagy leads to gradual loss of organelles including ER, resulting in autophagy-associated cell death of AVP neurons in FNDI mice.

Isolated Langerhans cell histiocytosis in the hypothalamic-pituitary region: a case report.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a rare disease that mainly affects children, but this disease is significantly rarer in patients who are older than 15 years. In this disease, any organ can be involved. The skeleton, skin and lung are commonly affected, and isolated hypothalamic-pituitary (HP) involvement is relatively rare. Here we report a 17-year-old adolescent with isolated HP-LCH of enlarged pituitary stalk presented with central diabetes insipidus (CDI). CASE PRESENTATION: A 17-year-old male adolescent with polydipsia and polyuria accompanied with elevated serum sodium level and low urine osmolality for 3 weeks was referred to our hospital. After admission, hormonal evaluation showed that his growth hormone (GH) was slightly elevated, and serum osmolality and glucose were normal. The fluid deprivation-vasopressin test demonstrated CDI. Imaging examination showed an obvious thickening of the pituitary stalk. Lymphocytic hypophysitis, sarcoidosis and granulation tissue lesions were suspected. After oral 1-deamino-8-Darginine vasopressin (DDAVP) and prednisone were administered for 2 months, symptoms were relieved, and he discontinued taking the drugs by himself. On reexamination, imaging revealed changes in the size and shape of the pituitary stalk, with thickened nodules. Then, a diagnostic biopsy of the pituitary stalk lesion was performed. Immunohistochemistry confirmed the definitive diagnosis of LCH. The clinical symptoms subsided with oral hormone replacements. CONCLUSION: CDI is a rare symptom in children and adolescents. Most of the causes are idiopathic, while others are caused by central nervous system (CNS) disorders. Meanwhile, lymphocytic hypophysitis, germinoma, LCH and other CNS disorders can all present as thickening of the pituitary stalk, diffuse enlargement of the pituitary gland, and weakening of high signal intensity in the neurohypophysis on magnetic resonance imaging (MRI). The differential diagnosis among these diseases depends on immunohistochemistry evidence.

Clinical presentation and outcome of children with central diabetes insipidus associated with a self-limited or transient pituitary stalk thickening, diagnosed as infundibuloneurohypophysitis.

OBJECTIVE: Despite lymphocytic or autoimmune infundibuloneurohypophysitis (INH) is an increasingly recognized aetiology in children with central diabetes insipidus (CDI); clinical data on epidemiology (clinical evolution, predisposing factors, complications), diagnosis and management of this entity are limited and mostly based on published case reports. The aim of this study was to gain a broader insight in the natural history of this disease by analysing the clinical presentation, radiological pituitary stalk changes, associated autoimmunity and hormonal deficiencies in children with CDI and a self-limiting or transient stalk thickening (ST), diagnosed as autoimmune infundibuloneurohypophysitis, during the last 15 years in four Belgian university hospitals. DESIGN AND PATIENTS: The medical files of nine CDI patients with a ST at initial presentation and no signs of Langerhans cell histiocytosis or germinoma at presentation and/or during follow-up of more than 1.5 years were reviewed. RESULTS: Age at presentation ranged from 3 to 14 years. Two patients had a positive family history of autoimmunity. Three children presented with associated growth failure, two with nausea and one with long-standing headache. Median maximal diameter of the stalk was 4.6 mm (2.7-10 mm). Four patients had extra-pituitary brain anomalies, such as cysts. One patient had central hypothyroidism, and another had a partial growth hormone deficiency at diagnosis. Within a mean follow-up of 5.4 (1.5-15) years, stalk thickening remained unchanged in two patients, regressed in one and normalized in six children. CDI remained in all, while additional pituitary hormone deficiencies developed in only one patient. CONCLUSIONS: In this series of children INH with CDI as initial presentation, CDI was permanent and infrequently associated with anterior pituitary hormone deficiencies, despite a frequent association with nonstalk cerebral lesions.

CENTRAL DIABETES INSIPIDUS: CLINICAL CHARACTERISTICS AND LONG-TERM COURSE IN A LARGE COHORT OF ADULTS.

OBJECTIVE: Central diabetes insipidus (CDI) is a rare heterogeneous condition with various underlying causes. This study sought to increase the still-limited data on the clinical characteristics and long-term course in adults diagnosed with CDI. METHODS: Data on demographics, presentation, imaging findings, affected pituitary axes, treatment, and complications were collected retrospectively from the files of 70 adult patients with CDI followed at a referral endocrine clinic. RESULTS: Forty women and 30 men were included. Mean age was 46.8 ± 15 years at the time of this study and 29.3 ± 20 years at CDI diagnosis. Twenty-eight patients were diagnosed in childhood. Forty patients (57%) acquired CDI following surgery. Main sellar pathologies were: craniopharyngioma, 17 patients (11 diagnosed in childhood); Langerhans histiocytosis, 10 patients (5 diagnosed in childhood); 7 patients (all diagnosed as adults) had a growth hormone-secreting adenoma; 12 patients (17%; 6 diagnosed in childhood) had idiopathic CDI. At least one anterior pituitary axis was affected in 73% of the cohort: 59% had growth hormone deficiency, 56% hypogonadism, 55% central hypothyroidism, 44% adrenocorticotropic hormone-cortisol deficiency. Patients with postoperative/trauma CDI (n = 44) tended to have multiple anterior pituitary axes deficits compared to the nonsurgical group of patients. All patients were treated with vasopressin preparations, mostly nasal spray. Hyponatremia developed in 32 patients, more in women, and was severe (<125 mEq/L) in 10 patients. Hypernatremia (>150 mEq/L) was noticed in 5 patients. Overall, the calculated complication rate was 22 in 1,250 treatment-years. CONCLUSION: Most adult patients with CDI have anterior pituitary dysfunction. Stability is usually achieved with long-term treatment. Women were more susceptible to desmopressin complications, albeit with an overall relatively low complication rate. ABBREVIATIONS: ACTH = adrenocorticotropic hormone CDI = central diabetes insipidus GH = growth hormone MRI = magnetic resonance imaging.

Electron Microscopic Study of the Inner Medulla in Rat Kidneys under Conditions of Vasopressin Treatment Combined with Prostaglandin Synthesis Blockade.

Ultrastructural changes in cells of the renal inner medulla involved in the realization of the antidiuretic effect of vasopressin under conditions of prostaglandin synthesis blockade were studied in the kidneys of Wistar rats and endogenous vasopressin-deficient homozygous Brattleboro rats. The results indicated uniform trend to an increase in the number of clathrincoated vesicles under conditions of hormone treatment combined with prostaglandin synthesis blockade in animals with different neurohypophyseal status. These changes reflected translocation of aquaporins and an increase in the permeability of the collecting tubular epithelium for water. Brattleboro rats, but not Wistar rats, exhibited ultrastructural signs of synthesis activation in the epithelium and widening of the intercellular gaps, which could indicate more intense paracellular water transport.

Central diabetes insipidus associated with impaired renal aquaporin-1 expression in mice lacking liver X receptor ß.

The present study demonstrates a key role for the oxysterol receptor liver X receptor ß (LXRß) in the etiology of diabetes insipidus (DI). Given free access to water, LXRß(-/-) but not LXRα(-/-) mice exhibited polyuria (abnormal daily excretion of highly diluted urine) and polydipsia (increased water intake), both features of diabetes insipidus. LXRß(-/-) mice responded to 24-h dehydration with a decreased urine volume and increased urine osmolality. To determine whether the DI was of central or nephrogenic origin, we examined the responsiveness of the kidney to arginine vasopressin (AVP). An i.p. injection of AVP to LXRß(-/-) mice revealed a partial kidney response: There was no effect on urine volume, but there was a significant increase of urine osmolality, suggesting that DI may be caused by a defect in central production of AVP. In the brain of WT mice LXRß was expressed in the nuclei of magnocellular neurons in the supraoptic and paraventricular nuclei of the hypothalamus. In LXRß(-/-) mice the expression of AVP was markedly decreased in the magnocellular neurons as well as in urine collected over a 24-h period. The persistent high urine volume after AVP administration was traced to a reduction in aquaporin-1 expression in the kidney of LXRß(-/-) mice. The LXR agonist (GW3965) in WT mice elicited an increase in urine osmolality, suggesting that LXRß is a key receptor in controlling water balance with targets in both the brain and kidney, and it could be a therapeutic target in disorders of water balance.

Endoplasmic reticulum stress in vasopressin neurons of familial diabetes insipidus model mice: aggregate formation and mRNA poly(A) tail shortening.

The immunoglobulin heavy chain binding protein (BiP) is an endoplasmic reticulum (ER) chaperone, which binds to newly synthesized secretory and transmembrane proteins to facilitate protein folding. BiP mRNA is expressed in the arginine vasopressin (AVP) neurons in the supraoptic nucleus of wild-type mice even in basal conditions, and the expression levels increase in response to dehydration. These data suggest that AVP neurons are subjected to ER stress. Familial neurohypophysial diabetes insipidus (FNDI) is caused by mutations in the gene locus of AVP. The mutant proteins could accumulate in the ER and possibly increase ER stress in the AVP neurons. We bred mice possessing a mutation causing FNDI, which manifested progressive polyuria, as do the patients with FNDI. Electron microscopic analyses demonstrated that aggregates accumulated in the ER of AVP neurons in FNDI mice. Despite polyuria, which could potentially induce dehydration, AVP mRNA expression was decreased in the supraoptic nucleus, and the AVP mRNA poly(A) tail length was shortened in FNDI mice compared with wild-type mice. Incubation of hypothalamic explants of wild-type mice with ER stressors caused shortening of the poly(A) tail length of AVP mRNA, accompanied by decreases in the expression. These data revealed a mechanism by which ER stress decreases poly(A) tail length of AVP mRNA, and this reduces the load of unfolded proteins that form the aggregates in ER of the AVP neurons in FNDI mice.

Prednisolone markedly reduced serum IgG4 levels along with the improvement of pituitary mass and anterior pituitary function in a patient with IgG4-related infundibulo-hypophysitis.

In 2011 a 76 year-old man with a medical history of diabetes, hypertension and autoimmune pancreatitis was admitted to our hospital because of anorexia, general malaise and repeated hypoglycemia. When he was 72 years old, he suffered from pancreatitis, and pancreas head tumor was operated. IgG4-related pancreatitis was diagnosed histopathologically. On admission anterior pituitary function test revealed impaired response of ACTH and cortisol to CRH, and no response of GH, TSH and gonadotropin to GHRH, TRH and LHRH, respectively. Baseline PRL level was elevated. Serum IgG and IgG4 levels were markedly elevated. Pituitary MRI showed significant enlargement of pituitary gland and stalk. Chest CT suggested IgG4-related lung disease. IgG4-related infundibulo-hypophysitis was diagnosed based on the above mentioned past history and results of present examinations. Twenty mg of hydrocortisone, followed by 20 mg of prednisolone (PSL) and 25 µg of levothyroxine markedly reduced serum IgG4 levels and ameliorated the symptom, the size of pituitary and stalk, and anterior pituitary function (TSH, GH and gonadotropin), although diabetes insipidus became apparent due to glucocorticoid administration. This is a typical case of IgG4-related hypophysitis in which PSL causes marked improvement of pituitary mass and pituitary function along with the reduction of serum IgG4 levels.

Erdheim-Chester disease and pituitary involvement: a unique case and the literature.

An early thirties man diagnosed with Erdheim-Chester disease (ECD) was simultaneously disclosed to have hypogonadotropic hypogonadism, central adrenal insufficiency, and GH deficiency in addition to central diabetes insipidus (CDI). Pituitary magnetic resonance imaging (MRI) showed swelling in the stalk, enlargement of the anterior lobe with delayed enhancement, and loss of high intensity of the posterior lobe on T1-weighted images, suggesting of pituitary involvement of ECD. Three months after starting treatment with interferon α and zoledronic acid, polyuria and polydipsia were ameliorated without DDAVP, accompanied with improvement of MRI. Simultaneously technetium-99m bone scintigraphy showed improvement, accompanied with a relief of bone pain and high fever. In contrast, he developed secondary hypothyroidism with slight enlargement of anterior pituitary gland without relapse of CDI, suggesting of different responses to treatment with interferon α between anterior pituitary lobe and posterior one. So far he continues to be replaced with deficient hormone replacement therapy. As for bone pain, it remains to be controlled with the decreased levels of bone resorption marker with decreased abnormal uptake in bone scintigraphy although zoledronic acid was discontinued for osteonecrosis of the jaw. For four years, he has not showed new involvement at other organs besides bones and the pituitary. While CDI is known to be very common in ECD, improvement of CDI has been reported in a few cases. Other endocrine manifestations, especially with detailed endocrine status, have been also reported in limited cases. Thus we report this case and review the literature.

Hypothalamic pituitary complications in Kabuki syndrome.

Kabuki syndrome is characterized by distinctive facial features, multiple anomalies and mental retardation. In this syndrome, structural CNS abnormalities are commonly observed, but congenital abnormalities in the pituitary gland or hypothalamus have rarely been reported. We searched the published medical literature on the complications in hypothalamic pituitary axis in this syndrome. As a result, only nine patients with Kabuki syndrome had been reported to have complications in hypothalamic pituitary axis in previous papers. Among the nine reported patients and one presented case in this report, GH deficiency was the most frequent complication and found in six patients. Precocious puberty and central diabetes insipidus (DI) was identified in two cases, respectively, and ACTH deficiency was found in one. One case had combination of GH deficiency and central DI. Three of the 10 patients demonstrated abnormal pituitary findings in MRI study. Two of the six patients with GH deficiency were accompanied with premature thelarche. This review highlights that patients with Kabuki syndrome could present various clinical manifestations due to abnormalities in hypothalamic pituitary axis.

Absence of anti-rabphilin-3A antibodies in children and young adults with idiopathic central diabetes insipidus: a potential clue to elucidating a tumor etiology.

BACKGROUND: Central diabetes insipidus (CDI) is a rare condition caused by various underlying diseases, including neoplasms, autoimmune diseases, and infiltrative diseases. Differentiating between CDI etiologies is difficult. What has initially been classified as "idiopathic" central diabetes insipidus might in fact underlie various pathogenic mechanisms that are less understood to date and/or are not obvious at initial presentation. Therefore, even if idiopathic CDI is diagnosed at the time of onset, it is common for tumors such as germinoma to develop during surveillance. Crucially, a delayed diagnosis of germinoma may be associated with a worse prognosis. Recently, the presence of anti-rabphilin-3A antibodies has been found to be a highly sensitive and specific marker of lymphocytic infundibuloneurohypophysitis, an autoimmune-mediated CDI. CASE PRESENTATION: We herein present two cases, namely, a 13-year-old boy (patient 1) and a 19-year-old young man (patient 2) who were diagnosed with idiopathic CDI. In both patients, panhypopituitarism developed. Magnetic resonance imaging revealed pituitary stalk thickening and pituitary swelling approximately 1 1/2 years after the onset of CDI. Western blotting did not reveal the presence of anti-rabphilin-3A antibodies in serum in either patient, suggesting that autoimmune mechanisms might not be involved. Both patients were subsequently diagnosed with germinoma on pathological examination. They received chemotherapy, followed by radiation therapy. Notably, testosterone and insulin-like growth factor-1 levels normalized, and libido and beard growth recovered after chemoradiotherapy in patient 2. CONCLUSION: Our data suggest that the absence of anti-rabphilin-3A antibodies in young patients clinically diagnosed with idiopathic CDI may increase the probability of the development of non-lymphocytic lesions, including germinoma. We thus recommend a more attentive approach at the onset of these diseases.

Pituitary Stalk Thickening: Causes and Consequences. The Children's Memorial Health Institute Experience and Literature Review.

Background: Pituitary stalk thickening (PST) is a rare abnormality in the pediatric population. Its etiology is heterogeneous. The aim of the study was to identify important clinical, radiological and endocrinological manifestations of patients with PST and follow the course of the disease. Materials and Methods: It is a study conducted in 23 patients (13 boys) with PST with/without central diabetes insipidus (CDI) diagnosed between 1990 and 2020 at Children's Memorial Health Institute (CMHI) in Warsaw, Poland. We analyzed demographic data, clinical signs and symptoms, radiological findings, tumor markers, hormonal results, treatment protocols and outcomes. Results: The median age at the diagnosis of PST was 9.68 years (IQR: 7.21-12.33). The median time from the onset of the symptoms to the diagnosis was 2.17 years (IQR: 1.12-3.54). The most common initially reported manifestations were polydipsia, polyuria and nocturia (82.6%); most of the patients (56.5%) also presented decreased growth velocity. Hormonal evaluation at the onset of PST revealed: CDI (91.3%), growth hormone deficiency (GHD) (56.5%), hyperprolactinemia (39%), central hypothyroidism (34.8%), adrenal insufficiency (9%), precocious puberty (8.7%). The majority of the patients were diagnosed with germinoma (seventeen patients - 73.9%, one of them with teratoma and germinoma). Langerhans cell histiocytosis (LCH) was identified in three patients (multisystem LCH in two patients, and unifocal LCH in one patient). A single case of atypical teratoid rhabdoid tumor, suspected low-grade glioma (LGG) and lymphocytic infundibuloneurohypophysitis (LINH). The overall survival rate during the observational period was 87.0%. Conclusions: The pituitary infundibulum presents a diagnostic imaging challenge because of its small size and protean spectrum of disease processes. Germinoma should be suspected in all children with PST, especially with CDI, even when neurological and ophthalmological symptoms are absent.

Pituitary and systemic autoimmunity in a case of intrasellar germinoma.

Germinomas arising in the sella turcica are difficult to differentiate from autoimmune hypophysitis because of similar clinical and pathological features. This differentiation, nevertheless, is critical for patient care due to different treatments of the two diseases. We report the case of an 11-year-old girl who presented with diabetes insipidus and growth retardation, and was found to have an intra- and supra-sellar mass. Initial examination of the pituitary biopsy showed diffuse lymphocytic infiltration of the adenohypophysis and absent placental alkaline phosphatase expression, leading to a diagnosis of hypophysitis and glucocorticoid treatment. Because of the lack of clinical and radiological response, the pituitary specimen was re-examined, revealing this time the presence of scattered c-kit and Oct4 positive germinoma cells. The revised diagnosis prompted the initiation of radiotherapy, which induced disappearance of the pituitary mass. Immunological studies showed that the patient's serum recognized antigens expressed by the patient's own germinoma cells, as well as pituitary antigens like growth hormone and systemic antigens like the Sjögren syndrome antigen B and alpha-enolase. The study first reports the presence of pituitary and systemic antibodies in a patient with intrasellar germinoma, and reminds us that diffuse lymphocytic infiltration of the pituitary gland and pituitary antibodies does not always indicate a diagnosis of autoimmune hypophysitis.

A case of central diabetes insipidus following probable type A/H1N1 influenza infection.

The major causes of central diabetes insipidus (CDI) are neoplastic or infiltrative lesions of the hypothalamus or pituitary gland, severe head injuries, or pituitary or hypothalamic surgery. Lymphocytic infundibuloneurophysitis (LINH) is associated with autoimmune inflammatory disease of the pituitary gland, but the exact etiology is unknown. CDI caused by viral infections has been rarely reported. Here, we describe the case of a 22-year-old man who was in good health until 2 months prior to admission, presented with acute development of polyuria and polydipsia, and showed increased urinary volume up to 9000 mL/day. The patient showed elevated serum osmolality and low urine osmolality, with a low level of antidiuretic hormone. Endocrinological findings revealed CDI, but his arterial pituitary function appeared normal. Magnetic resonance imaging revealed significant enlargement of the pituitary stalk. We suspected CDI due to LINH based on non-transsphenoidal biopsy findings. He was diagnosed as type A influenza,and given oral therapeutic agents. However, acute onset of polyuria and polydipsia occurred 10 days after the influenza diagnosis. The available epidemiological information regarding the outbreak of influenza around that time strongly suggested that the patient was infected with the A/H1N1 influenza virus, although this virus had not been detected on polymerase chain reaction testing. In the present case, the autoimmune mechanism of LINH may have been associated with novel influenza A/H1N1 virus infection.

Short-term stimulation of the thiazide-sensitive Na+-Cl- cotransporter by vasopressin involves phosphorylation and membrane translocation.

Vasopressin influences salt and water transport in renal epithelia. This is coordinated by the combined action of V2 receptor-mediated effects along distinct nephron segments. Modulation of NaCl reabsorption by vasopressin has been established in the loop of Henle, but its role in the distal convoluted tubule (DCT), an effective site for fine regulation of urinary electrolyte composition and the target for thiazide diuretics, is largely unknown. The Na+-Cl- cotransporter (NCC) of DCT is activated by luminal trafficking and phosphorylation at conserved NH2-terminal residues. Here, we demonstrate the effects of short-term vasopressin administration (30 min) on NCC activation in Brattleboro rats with central diabetes insipidus (DI) using the V2 receptor agonist desmopressin (dDAVP). The fraction of NCC abundance in the luminal plasma membrane was significantly increased upon dDAVP as shown by confocal microscopy, immunogold cytochemistry, and Western blot, suggesting increased apical trafficking of the transporter. Changes were paralleled by augmented phosphorylation of NCC as detected by antibodies against phospho-threonine and phospho-serine residues (2.5-fold increase at Thr53 and 1.4-fold increase at Ser71). dDAVP-induced phosphorylation of NCC, studied in tubular suspensions in the absence of systemic effects, was enhanced as well (1.7-fold increase at Ser71), which points to the direct mode of action of vasopressin in DCT. Changes were more pronounced in early (DCT1) than in late DCT as distinguished by the distribution of 11beta-hydroxysteroid dehydrogenase 2 in DCT2. These results suggest that the vasopressin-V(2) receptor-NCC signaling cascade is a novel effector system to adjust transepithelial NaCl reabsorption in DCT.

A homozygote frameshift mutation in OCLN gene result in Pseudo-TORCH syndrome type I: A case report extending the phenotype with central diabetes insipidus and renal dysfunction.

Intrauterine infections with the pathogens, including toxoplasmosis, other (syphilis, varicella, mumps, parvovirus, and HIV), rubella, cytomegalovirus, and herpes simplex (TORCH) in susceptible individuals during pregnancy, result in microcephaly, white matter disease, cerebral atrophy, and calcifications in the fetus. Pseudo-TORCH syndrome is an umbrella term, consisting of several syndromes, resultant from different genetic alterations and pathogenetic mechanisms. Band-like calcification with simplified gyration and polymicrogyria (BLC-PMG) is one of these conditions, resultant from biallelic mutations in the OCLN gene, located in the chromosome 5q13.2. OCLN gene encodes occludin, a tight junction protein, which is expressed in the endothelia. The absence of occludin in the developing brain subsequently results in abnormal blood-brain barrier, thus immune-cell mediated tissue damage and cortical malformation. Herein, we present a pediatric patient who had progressive microcephaly, spasticity, multi-drug resistant epilepsy, PMG and intracranial band-type calcifications, accompanied by central diabetes insipidus and renal dysfunction. Whole exome sequencing revealed a homozygote W58Ffs*10 (c.173_194del) frameshift mutation in the OCLN gene. Of 34 BLC-PMG cases with demonstrable OCLN mutations, only three had renal manifestations, which is responsible for the majority of the demises. This is the first case diagnosed as having central diabetes insipidus and responded to desmopressin treatment to the best of our knowledge, however, this clinical improvement could not prevent the patient from renal dysfunction. The patient deceased at four years of age from sepsis, therefore early diagnosis, optimal follow-up for renal involvement and infection prevention measures are necessary for the patients with BLC-PMG.

Forty-One Individuals With Mutations in the AVP-NPII Gene Associated With Familial Neurohypophyseal Diabetes Insipidus.

CONTEXT: Familial neurohypophyseal diabetes insipidus is a rare disease produced by a deficiency in the secretion of antidiuretic hormone and is caused by mutations in the arginine vasopressin gene. OBJECTIVE: Clinical, biochemical, and genetic characterization of a group of patients clinically diagnosed with familial neurohypophyseal diabetes insipidus, 1 of the largest cohorts of patients with protein neurophysin II (AVP-NPII) gene alterations studied so far. DESIGN: The AVP-NPII gene was screened for mutations by PCR followed by direct Sanger sequencing in 15 different unrelated families from Spain. RESULTS: The 15 probands presented with polyuria and polydipsia as the most important symptoms at the time of diagnosis. In these patients, the disease was diagnosed at a median of 6 years of age. We observed 11 likely pathogenic variants. Importantly, 4 of the AVP-NPII variants were novel (p.(Tyr21Cys), p.(Gly45Ser), p.(Cys75Tyr), p.(Gly88Cys)). CONCLUSIONS: Cytotoxicity seems to be due to consequences common to all the variants found in our cohort, which are not able to fold correctly and pass the quality control of the ER. In concordance, we found autosomal dominant familial neurohypophyseal diabetes insipidus in the 15 families studied.