Prevalence of advanced bone age in a cohort of patients who received cis-retinoic acid for high-risk neuroblastoma

In the last decade, 13-cis-retinoic acid (13-cis-RA) has been added to the treatment of patients with high-risk neuroblastoma. In survivors of neuroblastoma, short stature is consistently observed. Causes include growth hormone deficiency and poor growth of irradiated long bones. Within the survivorship program at CHOP, we have observed that a number of these patients also have advanced bone ages. Children treated with 13-cis-RA are at risk for advanced bone age that may dramatically impact their linear growth. Ongoing evaluation is necessary to examine the effect of 13-cis-RA on final adult height and to inform clinical practice in this cohort.     

Hypercalcemia and osteoblastic lesions induced by 13‐Cis‐retinoic acid mimicking relapsed neuroblastoma

A 6‐year‐old male diagnosed with extensive neuroblastoma was treated with chemotherapy, surgery, autotransplantation, and radiotherapy. He was then enrolled on a study to assess the monoclonal antibody Ch14.18 (anti‐GD2) with 13 cis‐retinoic acid. 13‐cis‐retinoic acid therapy caused severe bone pain and hypercalcemia. Bone scans showed multiple osteoblastic lesions suggesting recurrent disease however MIBG scans were negative. Serum markers of bone turnover were increased and the patient required pamidronate therapy to treat persistent hypercalcemia. Retinoic acid toxicity needs to be considered in the differential of painful osteoblastic lesions and/or hypercalcemia. MIBG scans can assist in differentiating from recurrent disease. Pediatr Blood Cancer 2009;53:666–668. © 2009 Wiley‐Liss, Inc.     

Iron overload following bone marrow transplantation in children: MR findings

Objective. The purpose of this study was to determine the incidence of post-transfusional iron overload in children after bone marrow transplantation by reviewing their magnetic resonance imaging (MR) findings. Materials and methods. We reviewed the abdominal MR studies of 13 children after autologous bone marrow transplantation. Nine of the children had also undergone MR prior to transplantation. Iron deposition in the liver, spleen and bone marrow was graded semi-quantitatively on both T1- and T2-weighted images. Serum ferritin levels and number of blood units given after bone marrow transplantation were recorded. Results. None of the pre-transplantation MR studies revealed iron overload. After bone marrow transplantation, three children showed normal liver and spleen. Iron overload in the liver was noted in ten patients (77 %), six of whom also showed iron overload in the spleen (46 %) and five in the bone marrow (38.5 %). The degree of hepatic iron overload was correlated significantly and splenic iron overload was correlated weakly with the number of blood transfusions (P = 0.01 and P > 0.01, respectively), but neither was correlated with the serum ferritin level. Conclusion. Iron overload commonly accompanies bone marrow transplantation. The observed pattern of iron deposition, in which the spleen was uninvolved in 40 % of patients demonstrating iron overload, is not typical of post-transfusional hemochromatosis. Received: 10 June 1997 Accepted: 10 June 1997     

Hypercalcemia and altered biochemical bone markers in post-bone marrow transplantation osteopetrosis: a case report and literature review

Autosomal recessive osteopetrosis is a rare disorder of bone resorption defect that results in generalized sclerotic bones and bone marrow failure. Allogeneic BMT is the only treatment for cure. One of the complications following a successful BMT is hypercalcemia that is a unique complication in this group of patients. We report a three-yr-old boy with osteopetrosis who developed hypercalcemia following the successful BMT. His maximal calcium level was 13.3 mg/dL. Markedly increased both bone formation and resorption markers were demonstrated along with hypercalcemia. These findings indicated an active donor-derived osteoclastic function and thus bone resorption following the successful donor engraftment in the patient. Treatment with hyperhydration, furosemide and bone resorption inhibitors, calcitonin, and bisphosphonate led to normalization of the serum calcium level. Bone resorption but not bone formation marker was persistently elevated despite having normocalcemia during a 16.5-month follow-up period.     

PTHrP-independent hypercalcemia with increased proinflammatory cytokines and bone resorption in two children with CD19-negative precursor B acute lymphoblastic leukemia

Hypercalcemia in childhood acute lymphoblastic leukemia (ALL) is rare and occasionally associated with parathyroid hormone-related protein (PTHrP). However, the pathogenesis of PTHrP-independent hypercalcemia remains unclear. We report two children with precursor B ALL who had marked hypercalcemia (15.8 and 16.6 mg/dl, respectively) and disseminated osteolysis. Serum tumor necrosis factor-alpha (TNF-alpha) and IL-6 were markedly elevated, whereas 1,25(OH)(2) vitamin D(3), intact PTH and PTHrP were decreased or undetected. Analysis of urinary deoxypyridinoline (DPY) or bone biopsy of the osteolytic lesion showed an increased bone resorption, and administration of bisphosphonate improved the hypercalcemia. Patients had ALL with immunophenotype positive for CD10, CD34, and HLA-DR but negative for CD19 and obtained remission with chemotherapy. These findings suggest that increased osteoclastic bone resorption via stimulation with TNF-alpha and IL-6 may be mechanism causing PTHrP-independent hypercalcemia in some patients with precursor B ALL lacking CD19 expression.     

CD19 negative precursor B acute lymphoblastic leukemia presenting with hypercalcemia

A 9-month-old infant presented with hypercalcemia and lytic bone lesions. Suspicion for malignancy led to a bone marrow examination, which showed replacement of the marrow by a small round blue cell infiltrate. Flow cytometric analysis of these cells showed an unusual immunophenotype in that these cells were dim CD45, HLA-DR, and CD10 positive, but CD19, CD20, CD79a, and CD34 negative. Southern blotting showed clonal rearrangement of immunoglobulin heavy chain (IgH) which confirmed a diagnosis of precursor B acute lymphoblastic leukemia (ALL). He received supportive treatment with hydration and pamidronate, but had recurrent episodes of hypercalcemia. Once the correct diagnosis of ALL was established, the patient was treated with an infantile ALL chemotherapeutic regimen and the hypercalcemia resolved. This case highlights the usefulness of immunoglobulin gene rearrangement studies in atypical cases of ALL.     

Retinoic-acid-resistant neuroblastoma cell lines show altered MYC regulation and high sensitivity to fenretinide

BACKGROUND: High-dose, pulse-13-cis-retinoic acid (13-cis-RA) given after intensive cytotoxic therapy improves event-free survival for high-risk neuroblastoma (NB), but more than 50% of patients have tumor recurrence. PROCEDURE: We conducted multistep selection for resistance to all-trans-retinoic acid (ATRA) in NB cell lines with (SMS-KCNR and LA-N-5) or without (SMS-LHN) MYCN genomic amplification. RESULTS: After 12 exposures to 10 microM ATRA, the two MYCN-amplified cell lines (KCNR 12X RR and LA-N-5 12X RR) showed partial resistance to the cytostatic/differentiation effects of ATRA; complete resistance was seen in LHN 12X RR. ATRA-selected cells showed general RA resistance (cross-resistance to 13-cis-RA). Transient (KCNR 12 X RR, LA-N-5 12X RR) or sustained (LHN 12X RR) novel overexpression of c-myc was associated with RA resistance. RA-insensitive overexpression of MYCN by transduction in SMS-LHN also conferred RA resistance. Both parental and RA-resistant lines showed 2-4 logs of cell kill in response to N-(4-hydroxyphenyl)retinamide (4- HPR, fenretinide). Compared to parental lines, 4-HPR achieved 1-3 log greater cell kills in RA-resistant LHN 12X RR, LA-N-5 12X RR, KCNR 12X RR, and MYCN-transduced SMS-LHN or SK-N-RA. NB cell lines (n = 26) from 21 different patients showed that 16 of 26 (62%) were sensitive to 4-HPR (LC(90) < 10 microM), including lines established at relapse after myeloablative and/or 13-cis-RA therapy. CONCLUSION: Thus, RA-resistant NB cell lines can be sensitive (and in some cases collaterally hypersensitive) to 4-HPR.     

Persistent elevated serum levels of intact parathyroid hormone after reoperation for primary hyperparathyroidism and after pamidronate therapy

Primary hyperparathyroidism is a life-threatening rare disorder. It is seen as a result of neonatal primary hyperparathyroidism, familial hypocalciuric hypercalcemia, increased vitamin D levels and inactivation of calcium sensing receptor mutations. The clinical findings are hypotonia, bone demineralization, hypercalcemia and parathyroid hyperplasia. We present a six-month-old female patient, the first child of nonconsanguineous parents, who was referred for the investigation of failure to thrive, vomiting, constipation, fever, abdominal distention and hypotonia. Physical examination revealed weight under 3rd percentile, height 3rd-10th percentile, decreased subcutaneous fat, and distention of the abdomen. In neurological examination, hypotonia, motor-mental retardation, and active deep tendon reflexes were found. The biochemical values at the time of admission revealed primary hyperparathyroidism. Since hypercalcemia did not respond to calcitonin therapy and due to the mortality of hypercalcemia, parathyroidectomy was performed. Because hyperparathyroidism and hypercalcemia continued, angiography was done which revealed increased parathyroid hormone levels in the periphery of the innominate vein. Exploratory surgery followed, but hyperparathyroidism and hypercalcemia persisted after all of these procedures. Calcium-sensing receptor mutations and supernumerary gland were considered. Because hypercalcemia persisted, pamidronate therapy was initiated on a monthly basis.     

Immobilization hypercalcemia after single limb fractures in children and adolescents

Immobilization hypercalcemia following a single limb fracture of one weight bearing bone has been reported rarely in the pediatric age group. Nevertheless, in six of 12 patients immobilization hypercalcemia developed, associated with elevations in the urinary calcium/creatinine ratio and serum levels of ionized calcium after a single limb fracture of a weight-bearing bone during this two-year study period. We suggest that immobilization hypercalcemia occurs frequently in both children and adolescents after a single limb fracture of one weight-bearing bone, exercises in bed fail to prevent immobilization hypercalcemia, serial measurements of the serum ionized calcium and the urinary calcium/creatinine ratio are critical measures in treating such patients, and though complete mobilization is curative, transient calcitonin therapy is highly effective in reversing the disorders in calcium metabolism.     

Prophylaxis of vitamin D deficiency in hypothyroidism in the newborn infant

This study deals with the relationship between the occurrence of hypercalcemia and the administration of prophylactic doses of vitamin D in children with hypothyroidism, before and during L-thyroxine (LT4) treatment. The goal of the study was to determine the dosage of vitamin D necessary to prevent rickets without inducing hypercalcemia. There was a 23% prevalence of hypercalcemia at the time of the diagnosis of hypothyroidism by screening whereas it was 21% in the children who were not given vitamin D during the first 3 months of LT4 treatment. This figure was significantly higher in those who were given vitamin D during the first 3 months of treatment and reached 70%. However, one of the 19 children not given vitamin D presented with biological signs evoking vitamin D deficiency. In conclusion, in hypothyroid infants, vitamin D should be administered carefully during the first 6 months of treatment and restricted to children at risk for developing vitamin D deficiency.     

Disorders of bone metabolism in premature infants

Extremely low birth weight infants are particularly prone to rickets (osteopenia) due to their rapid growth and to deficient intake of calcium and phosphate. In some premature infants suffering from phosphate depletion hypercalcemia syndrome may precede bone demineralisation. Additionally, the adverse effects of calciprivic drugs (phenytoin, phenobarbital, glucocorticoids, furosemide, heparin) contributing to the development of neonatal rickets are discussed. Phosphorus depleted or heparin treated experimental animals develop impairment of mineralisation as manifested by rickets or osteomalacia. Some clinical cases of neonatal rickets are reported and a dosage schedule for parenteral infusion of minerals is given.     

Bisphosphonates: from grandparents to grandchildren

Bisphosphonates are synthetic analogues of pyrophosphate that inhibit bone resorption by their action on osteoclasts. Bisphosphonates have been extensively used in the elderly with primary and secondary osteoporosis, Paget's disease, and hypercalcemia of malignancy. In recent years, bisphosphonates have been used to treat children acutely for resistant hypercalcemia and chronically for various metabolic bone diseases. The theoretical concerns of possible adverse effects of these drugs on the growing skeleton have not been proven to be true. In the present review, we have critically analyzed the available literature on bisphosphonate therapy in both adult and pediatric clinical trials. Although not yet approved by the FDA for use in children, bisphosphonates, from published experience, demonstrate benefit to the child with no serious adverse effects. Based on the literature analysis the review furnishes detailed recommendations and practical guidelines regarding the use of oral and intravenous bisphosphonates in children. Bisphosphonates might be the first agents to provide the pediatrician with an opportunity to treat mineral and bone disorders of childhood, which until recently did not have satisfactory therapy.     

Altered mental status and hematemesis in a child with hypercalcemia

Altered mental status in a child is a potentially life-threatening condition with a broad differential including vascular, toxin-mediated, infectious, metabolic, and traumatic causes. Hypercalcemia is a rare cause of altered mental status in children. We report a case of a 13-month-old boy with familial hypocalciuric hypercalcemia who presented to our emergency department with altered mental status and hematemesis. Familial hypocalciuric hypercalcemia is a rare cause of hypercalcemia that usually presents with asymptomatic hypercalcemia. This case illustrates the presentation of severe hypercalcemia and reviews the initial management and evaluation of hypercalcemia in children.     

Severe hypercalcemia associated with Williams syndrome successfully treated with pamidronate infusion therapy

Infantile hypercalcemia becomes manifest in 15% of patients with Williams syndrome (WS) and generally is not clinically severe. However, some patients with WS can have severe hypercalcemia and do not respond well to traditional therapies. Recently, pamidronate has been used in the treatment of childhood hypercalcemia associated with many disorders, but there is little experience with the treatment of hypercalcemia with bisphosphonates in patients with WS. We present a 17-month-old female patient, who had been diagnosed as WS by genetic analysis, admitted to our clinic for the investigation of severe hypercalcemia (4.02 mmol/L). Because the patient did not respond very well to fluid administration, furosemide infusion, and dietary calcium restriction, pamidronate infusion was performed and calcium levels returned to normal within 2 days. This case report is presented to point out that pamidronate therapy seems to be a safe and efficient way of treating life-threatening hypercalcemia in WS.     

吸入糖皮质激素对哮喘儿童骨龄及生长发育的影响

目的：长期吸入糖皮质激素是哮喘的首选治疗方法,但国内外对于年幼儿童长期吸入糖皮质激素治疗的安全性仍有争议,本研究旨在探讨支气管哮喘患儿吸入糖皮质激素对骨龄及生长发育的影响。方法：73例支气管哮喘患儿给予丙酸氟替卡松吸入治疗,剂量250 μg/d,3个月后减量1/3续用3个月,再减为125 μg/d续用6个月,治疗后观察疗效,治疗前后分别测量骨龄、身高、体重。结果：入选患儿治疗后身高、体重及RUS骨龄增长与正常儿童差异无统计学意义（P>0.05）;体重指数(BMI)治疗前后差异无统计学意义（P>0.05）;治疗前后C骨龄与年龄差值分别为-0.2（-0.6,0.8）岁、-0.5（-1.0、0.6)岁,治疗后明显比治疗前延迟（P<0.05）。结论：哮喘患儿吸入糖皮质激素治疗 1年对C骨龄发育有一定抑制作用,对RUS骨龄、身高、体重及BMI无明显影响;长期糖皮质激素治疗的患儿应监测生长发育状况。     

Hypocalciuric hypercalcemia presenting as neonatal rib fractures: a newly described mutation of the calcium-sensing receptor gene

A 2-week-old infant presented with bilateral rib fractures, hypercalcemia, and subperiosteal bone erosions. Parathyroid hormone levels were elevated and urine calcium low. Her parent's laboratory test results were normal. Gene sequencing revealed a new mutation of the calcium-sensing receptor gene, causing severe neonatal hyperparathyroidism, a variant of hypocalciuric hypercalcemia. This is a rare cause of neonatal hyperparathyroidism and nonabusive fractures.     

Comparison of low and high dose of vitamin D treatment in nutritional vitamin D deficiency rickets

In this study, we compared three different therapy modes (150,000 IU, 300,000 IU, and 600,000 IU vitamin D p.o.) in infants with nutritional vitamin D deficiency rickets (VDR). Our purpose was to determine the most effective dosage of vitamin D with least side effects for treating VDR. The study included 56 patients, 3-36 months of age, with nutritional VDR and 20 age-matched control infants. In all infants, serum calcium, phosphorus, alkaline phosphatase, magnesium, serum 25-hydroxycholecalciferol, plasma intact parathormone levels and urinary Ca/creatine ratio were determined. Of 56 patients, 52 were able to be followed long-term. These patients were reexamined on the 3rd day, 7-10th day, and 25-30th day after treatment. On the 30th day post-treatment, we did not find any difference between the doses in the improvement of rickets. However, hypercalcemia was present in eight infants who had been administered 300,000 IU (two infants) and 600,000 IU (six infants) of vitamin D. In conclusion, our findings showed that 150,000 IU or 300,000 IU of vitamin D was adequate in the treatment of VDR, but 600,000 IU of vitamin D may carry the risk of hypercalcemia.     

The role of bisphosphonates in diseases of childhood

Bisphosphonates are synthetic analogues of pyrophosphate that inhibit bone resorption by their action on osteoclasts. In recent years, bisphosphonates have been used in children for treatment of a growing number of disorders associated primarily with generalized or localized osteoporosis, metabolic bone diseases, heterotopic calcification in soft tissues, and for resistant hypercalcemia. In the present review we discuss the pharmacological aspects of bisphosphonates and related bone pathophysiology, review the pediatric literature on the role of bisphosphonates in childhood diseases and our experience with these drugs. The theoretical concerns of possible adverse effects of these drugs on the growing skeleton have not materialized in the limited pediatric clinical experience. Bisphosphonates provide the pediatrician with an opportunity to treat mineral and bone disorders of childhood which until recently did not have satisfactory therapy, at the same time, being aware of the theoretical concerns on microdamage accumulation in bone, bone quality and teratogenic potential of these drugsSupported by the Sam and Helen Kaplan Research Fund in Pediatric Nephrology