The Experts below are selected from a list of 183 Experts worldwide ranked by ideXlab platform
Hiroo Niimi - One of the best experts on this subject based on the ideXlab platform.
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Transient pseudohypoparathyroidism of the neonate
European Journal of Endocrinology, 1995Co-Authors: Masanori Minagawa, Toshiyuki Yasuda, Yasuyuki Kobayashi, Hiroo NiimiAbstract:: We report three neonates with transient hypoparathyroidism with elevated parathyroid hormone (PTH) levels to clarify further the pathogenesis of late Neonatal Hypocalcemia and calcium homeostasis. Clinical signs were seizures starting at age of 10 and 11 days. The biochemical features were characterized by transient Hypocalcemia and hyperphosphatemia due to a high transport maximum of the phosphate/glomerular filtration rate, despite high PTH levels. All had normal magnesium and calcidiol levels (at least 5 micrograms/l) for their age, and this precludes hypoparathyroidism due to low magnesium levels and hyperparathyroidism due to overt vitamin D deficiency. To diagnose pseudohypoparathyroidism type I, intravenous human PTH (1-34) infusions were performed; however, they showed brisk responses of plasma and/or urine cyclic AMP in response to the PTH infusion, but the phosphaturic response to the PTH was sluggish compared to the controls. All three showed an increase in serum alkaline phosphatase activity, suggesting PTH stimulation of osteoblasts. They were treated initially with calcium lactate or (1 alpha)-hydroxycalciol/calcitriol. Their hypoparathyroid condition, however, was transient; they maintained normal serum calcium and PTH levels without medication before the age of 6 months. The etiology, possibly intracellular signal transduction distal to cyclic AMP and/or distinct from adenylate cyclase in the kidney, is developmental and the condition was resolved completely within 6 months of age. We have termed this condition "transient pseudohypoparathyroidism of the neonate".
Soumya Adhikari - One of the best experts on this subject based on the ideXlab platform.
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transient Neonatal Hypocalcemia presentation and outcomes
Pediatrics, 2012Co-Authors: Teena C Thomas, Joshua M Smith, Perrin C White, Soumya AdhikariAbstract:OBJECTIVE: To determine the incidence of moderate-to-severe transient Neonatal Hypocalcemia in term neonates and to describe the characteristics of affected infants and the outcomes of their management. METHODS: We reviewed medical records of all term infants <31 days of age who presented to Children’s Medical Center Dallas from 2001 to 2009 with Hypocalcemia (ionized calcium <1.00 mmol/L [4.00 mg/dL]). RESULTS: Seventy-eight infants met criteria. Median (interquartile range) age at admission was 8.0 (7.0–10.0) days, and median duration of admission was 3.0 (2.0–4.0) days. Most infants were male (71.8%) and Hispanic (62.8%). Neonates were generally severely hypocalcemic and hyperphosphatemic. Seventy-five of 78 were hypomagnesemic, and the majority had low or inappropriately normal parathyroid hormone responses. Levels of 25-hydroxyvitamin D were ≤62.4 nmol/L (25 ng/mL) in all 42 infants in whom they were determined. All infants responded to therapy of limited duration with 1 or more of the following: calcium supplements, calcitriol, low phosphorus formula, and magnesium supplementation. Neuroimaging did not affect management decisions in any neonate. CONCLUSIONS: Moderate-to-severe late-onset Neonatal Hypocalcemia is more common in Hispanic and male infants, is often a sign of coexistent vitamin D insufficiency or deficiency and hypomagnesemia, and is readily managed with therapy of limited duration. Neonates presenting with seizures who are found to be hypocalcemic are unlikely to benefit from neuroimaging evaluations. * Abbreviations: 25(OH)D — : 25-hydroxyvitamin D IQR — : interquartile range IV — : intravenous PTH — : parathyroid hormone
Masanori Minagawa - One of the best experts on this subject based on the ideXlab platform.
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Transient pseudohypoparathyroidism of the neonate
European Journal of Endocrinology, 1995Co-Authors: Masanori Minagawa, Toshiyuki Yasuda, Yasuyuki Kobayashi, Hiroo NiimiAbstract:: We report three neonates with transient hypoparathyroidism with elevated parathyroid hormone (PTH) levels to clarify further the pathogenesis of late Neonatal Hypocalcemia and calcium homeostasis. Clinical signs were seizures starting at age of 10 and 11 days. The biochemical features were characterized by transient Hypocalcemia and hyperphosphatemia due to a high transport maximum of the phosphate/glomerular filtration rate, despite high PTH levels. All had normal magnesium and calcidiol levels (at least 5 micrograms/l) for their age, and this precludes hypoparathyroidism due to low magnesium levels and hyperparathyroidism due to overt vitamin D deficiency. To diagnose pseudohypoparathyroidism type I, intravenous human PTH (1-34) infusions were performed; however, they showed brisk responses of plasma and/or urine cyclic AMP in response to the PTH infusion, but the phosphaturic response to the PTH was sluggish compared to the controls. All three showed an increase in serum alkaline phosphatase activity, suggesting PTH stimulation of osteoblasts. They were treated initially with calcium lactate or (1 alpha)-hydroxycalciol/calcitriol. Their hypoparathyroid condition, however, was transient; they maintained normal serum calcium and PTH levels without medication before the age of 6 months. The etiology, possibly intracellular signal transduction distal to cyclic AMP and/or distinct from adenylate cyclase in the kidney, is developmental and the condition was resolved completely within 6 months of age. We have termed this condition "transient pseudohypoparathyroidism of the neonate".
Anne S. Bassett - One of the best experts on this subject based on the ideXlab platform.
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Neonatal Hypocalcemia, Neonatal seizures, and intellectual disability in 22q11.2 deletion syndrome
Genetics in Medicine, 2014Co-Authors: Evelyn Ning Man Cheung, Susan R. George, Danielle M. Andrade, Eva W.c. Chow, Candice K. Silversides, Anne S. BassettAbstract:Genet Med 16 1, 40–44. Purpose: Hypocalcemia is a common endocrinological condition in 22q11.2 deletion syndrome. Neonatal Hypocalcemia may affect neurodevelopment. We hypothesized that Neonatal Hypocalcemia would be associated with rare, more severe forms of intellectual disability in 22q11.2 deletion syndrome. Methods: We used a logistic regression model to investigate potential predictors of intellectual disability severity, including Neonatal Hypocalcemia, Neonatal seizures, and complex congenital heart disease, e.g., interrupted aortic arch, in 149 adults with 22q11.2 deletion syndrome. Ten subjects had moderate-to-severe intellectual disability. Results: The model was highly significant ( P < 0.0001), showing Neonatal seizures ( P = 0.0018) and Neonatal Hypocalcemia ( P = 0.047) to be significant predictors of a more severe level of intellectual disability. Neonatal seizures were significantly associated with Neonatal Hypocalcemia in the entire sample ( P < 0.0001), regardless of intellectual level. There was no evidence for the association of moderate-to-severe intellectual disability with other factors such as major structural brain malformations in this sample. Conclusion: The results suggest that Neonatal seizures may increase the risk for more severe intellectual deficits in 22q11.2 deletion syndrome, likely mediated by Neonatal Hypocalcemia. Neonatal Hypocalcemia often remains unrecognized until the postseizure period, when damage to neurons may already have occurred. These findings support the importance of early recognition and treatment of Neonatal Hypocalcemia and potentially Neonatal screening for 22q11.2 deletions.
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Neonatal Hypocalcemia Neonatal seizures and intellectual disability in 22q11 2 deletion syndrome
Genetics in Medicine, 2014Co-Authors: Evelyn Ning Man Cheung, Susan R. George, Danielle M. Andrade, Eva W.c. Chow, Candice K. Silversides, Anne S. BassettAbstract:Neonatal Hypocalcemia, Neonatal seizures, and intellectual disability in 22q11.2 deletion syndrome
Pat Mahachoklertwattana - One of the best experts on this subject based on the ideXlab platform.
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Transient Neonatal hypoparathyroidism in two siblings unmasking maternal normocalcemic hyperparathyroidism
European Journal of Pediatrics, 2008Co-Authors: Preamrudee Poomthavorn, Boonsong Ongphiphadhanakul, Pat MahachoklertwattanaAbstract:Hypoparathyroidism is one of the recognized causes of late-onset Neonatal Hypocalcemia. Maternal hypercalcemic hyperparathyroidism has been shown to suppress fetal parathyroid glands, causing transient Neonatal hypoparathyroidism. We report two siblings (6 years apart) with transient hypoparathyroidism presented with hypocalcemic seizures during the first 2 weeks of life. Subsequent investigation revealed an unrecognized normocalcemic hyperparathyroidism with nephrocalcinosis in the mother. Maternal hyperparathyroidism was caused by two parathyroid adenomas. In conclusion, our report highlights the importance of careful evaluation of Neonatal hypoparathyroidism in uncovering an unrecognized, asymptomatic hyperparathyroidism in the mother.
