Josephine Ho

Incident vertebral fractures and risk factors in the first three years following glucocorticoid initiation among pediatric patients with rheumatic disorders

Vertebral fractures are an important yet underrecognized manifestation of osteoporosis in children with chronic, glucocorticoid‐treated illnesses. Our goal was to determine the incidence and clinical predictors of vertebral fractures in the 3 years following glucocorticoid initiation among pediatric patients with rheumatic disorders. Incident vertebral fractures were evaluated according to the Genant semiquantitative method on lateral radiographs at baseline and then annually in the 3 years following glucocorticoid initiation. Extended Cox models were used to assess the association between vertebral fractures and clinical risk predictors. A total of 134 children with rheumatic disorders were enrolled in the study (mean ± standard deviation (SD) age 9.9 ± 4.4 years; 65% girls). The unadjusted vertebral fracture incidence rate was 4.4 per 100 person‐years, with a 3‐year incidence proportion of 12.4%. The highest annual incidence occurred in the first year (6.0%; 95% confidence interval (CI) 2.9% to 11.7%). Almost one‐half of the patients with fractures were asymptomatic. Every 0.5 mg/kg increase in average daily glucocorticoid (prednisone equivalents) dose was associated with a twofold increased fracture risk (hazard ratio (HR) 2.0; 95% CI 1.1 to 3.5). Other predictors of increased vertebral fracture risk included: (1) increases in disease severity scores between baseline and 12 months; (2) increases in body mass index Z‐scores in the first 6 months of each 12‐month period preceding the annual fracture assessment; and (3) decreases in lumbar spine bone mineral density Z‐scores in the first 6 months of glucocorticoid therapy. As such, we observed that a clinically significant number of children with rheumatic disorders developed incident vertebral fractures in the 3 years following glucocorticoid initiation. Almost one‐half of the children were asymptomatic and thereby would have been undiagnosed in the absence of radiographic monitoring. In addition, discrete clinical predictors of incident vertebral fractures were evident early in the course of glucocorticoid therapy.

Incident Vertebral Fractures in Children With Leukemia During the Four Years Following Diagnosis

OBJECTIVES The purpose of this article was to determine the incidence and predictors of vertebral fractures (VF) during the 4 years after diagnosis in pediatric acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS Children were enrolled within 30 days of chemotherapy initiation, with incident VF assessed annually on lateral spine radiographs according to the Genant method. Extended Cox models were used to assess the association between incident VF and clinical predictors. RESULTS A total of 186 children with ALL completed the baseline evaluation (median age, 5.3 years; interquartile range, 3.4-9.7 years; 58% boys). The VF incidence rate was 8.7 per 100 person-years, with a 4-year cumulative incidence of 26.4%. The highest annual incidence occurred at 12 months (16.1%; 95% confidence interval [CI], 11.2-22.7), falling to 2.9% at 4 years (95% CI, 1.1-7.3). Half of the children with incident VF had a moderate or severe VF, and 39% of those with incident VF were asymptomatic. Every 10 mg/m(2) increase in average daily glucocorticoid dose (prednisone equivalents) was associated with a 5.9-fold increased VF risk (95% CI, 3.0-11.8; P < .01). Other predictors of increased VF risk included VF at diagnosis, younger age, and lower spine bone mineral density Z-scores at baseline and each annual assessment. CONCLUSIONS One quarter of children with ALL developed incident VF in the 4 years after diagnosis; most of the VF burden was in the first year. Over one third of children with incident VF were asymptomatic. Discrete clinical predictors of a VF were evident early in the patients clinical course, including a VF at diagnosis.

The choice of normative pediatric reference database changes spine bone mineral density Z-scores but not the relationship between bone mineral density and prevalent vertebral fractures.

OBJECTIVES Our objectives were to assess the magnitude of the disparity in lumbar spine bone mineral density (LSBMD) Z-scores generated by different reference databases and to evaluate whether the relationship between LSBMD Z-scores and vertebral fractures (VF) varies by choice of database. PATIENTS AND DESIGN Children with leukemia underwent LSBMD by cross-calibrated dual-energy x-ray absorptiometry, with Z-scores generated according to Hologic and Lunar databases. VF were assessed by the Genant method on spine radiographs. Logistic regression was used to assess the association between fractures and LSBMD Z-scores. Net reclassification improvement and area under the receiver operating characteristic curve were calculated to assess the predictive accuracy of LSBMD Z-scores for VF. RESULTS For the 186 children from 0 to 18 years of age, 6 different age ranges were studied. The Z-scores generated for the 0 to 18 group were highly correlated (r ≥ 0.90), but the proportion of children with LSBMD Z-scores ≤-2.0 among those with VF varied substantially (from 38-66%). Odds ratios (OR) for the association between LSBMD Z-score and VF were similar regardless of database (OR = 1.92, 95% confidence interval 1.44, 2.56 to OR = 2.70, 95% confidence interval 1.70, 4.28). Area under the receiver operating characteristic curve and net reclassification improvement ranged from 0.71 to 0.75 and -0.15 to 0.07, respectively. CONCLUSIONS Although the use of a LSBMD Z-score threshold as part of the definition of osteoporosis in a child with VF does not appear valid, the study of relationships between BMD and VF is valid regardless of the BMD database that is used.

Diabetic ketoacidosis and pediatric stroke

THE CASE: A 6-year-old previously healthy right-handed girl presented with a 3-day history of progressive epigastric abdominal pain, polydipsia and secondary nocturnal enuresis and a 2-week history of weight loss of 5 kg. Her initial assessment revealed tachypnea with Kussmauls respiration,

Pediatric stroke associated with new onset type 1 diabetes mellitus: case reports and review of the literature.

Abstract:  Neurological deterioration in children with diabetic ketoacidosis (DKA) is commonly caused by cerebral edema. However, stroke should also be suspected when focal neurological deficits are apparent, because children with hyperglycemia and DKA are prone to thrombosis. We report three cases of pediatric stroke associated with new onset type 1 diabetes mellitus (T1DM). The first case presented with sinovenous thrombosis, and the other two cases presented in DKA and had a late diagnosis of ischemic stroke following neurological deterioration. Our recent experiences and review of the literature emphasize the importance of early diagnosis, investigation, and treatment for patients that present with new onset T1DM and stroke.

Massive levothyroxine ingestion in a pediatric patient: case report and discussion.

We describe the course of a toddler who ingested a massive amount of levothyroxine and review treatment options for such overdoses. A 2½-year-old boy presented shortly after an ingestion of up to 7.6 mg of levothyroxine (potentially as much as 700 μg/kg). He was initially asymptomatic, treated with oral charcoal 1 g/kg, and discharged home from the emergency department after a few hours. He returned approximately 24 hours later with a temperature of 38.5°C, heart rate of 163 beats per minute, respiratory rate of 30 breaths per minute, and blood pressure of 136/70 mm Hg. He had a slightly decreased appetite and no signs or symptoms of infection. He was admitted to hospital and treated with oral acetaminophen. The initial free thyroxine (T4) was > 100 pmol/L and free triiodothyronine (T3) was 35.3 pmol/L. The patient had desquamation of the palms and soles, hair loss, and irritability during the month following the ingestion. Resolution of the elevated free T4 occurred by 12 days post-ingestion and normalization of the thyroid-stimulating hormone by 7 weeks post-ingestion. There were no long-term sequelae. Levothyroxine overdose can result in significant complications, including seizures and arrhythmias, both of which should be monitored for. However, as our case illustrates, massive ingestion of levothyroxine in children typically follows a benign course.

Virilization in two pre-pubertal children exposed to topical androgen

Abstract Androgen replacement therapy for male hypogonadism may be prescribed utilizing intramuscular, oral or more recently, topical formulations. With topical formulations, there is a risk of person-to-person transmission if appropriate precautions are not taken. We describe two cases of virilization in pre-pubertal children following passive transfer of paternal topical testosterone. A 21 month old male was referred with a 6 week history of pubic hair, phallic growth, and linear growth spurt. Genital examination revealed Tanner stage 2 pubic hair and Tanner stage 3 phallic development, which was discordant with the pre-pubertal testicular size (2 mL bilaterally). A 3 year 8 month old girl was referred for a 2 month history of increasing pubic hair development. Examination revealed Tanner stage 2 pubic hair and Tanner stage 1 breast development. Both of these patients had fathers who had been diagnosed with hypogonadism and were being treated with topical androgen gel therapy, which they applied to their arms and chest before bed. In addition, both patients often slept with their parents resulting in skin-to-skin contact. Investigations were consistent with gonadotropin independent virilization with both patients demonstrating elevated testosterone levels. Testosterone levels returned to normal pre-pubertal levels with no further development of secondary sexual characteristics following discontinuation of exposure to topical testosterone. Precautions must be taken to prevent person-to-person transfer of topical steroids. With the increasing popularity of topical steroids for the treatment of low testosterone, it is imperative that these therapies be prescribed and utilized judiciously to prevent harm, specifically gonadotropin-independent virilization.

Kabuki Syndrome and Crohn Disease in a Child with Familial Hypocalciuric Hypercalcemia

ABSTRACT Background: Familial hypocalciuric hypercalcemia (FHH) results from a mutation of the calcium sensing receptor (CASR) gene and typically presents as asymptomatic hypercalcemia with inappropriately low urinary calcium excretion and normal or mildly elevated levels of parathyroid hormone. Objective: To describe a case of FHH associated with Kabuki syndrome and Crohn disease. Method: Genomic DNA was screened for CASR mutations and a retrospective chart review was performed. Results: Heterozygosity was observed in exon 3, which encodes a portion of the extra-cellular domain. Sequencing revealed a n.476T>G nucleotide transversion, predicting a non-conservative substitution of arginine for leucine at codon 159 (p.L159R). Conclusion: An association between Kabuki syndrome and autoimmune disease has been described in the literature, which may explain the connection between Kabuki syndrome and Crohn disease. However, it remains unclear if there is a link between FHH, Kabuki syndrome and Crohn disease in this case.

Turner Syndrome and apparent absent uterus: a case report and review of the literature

Abstract We report on a patient who initially presented with delayed puberty and an absent uterus on imaging with ultrasound and MRI. She was subsequently diagnosed with Turner Syndrome. Turner Syndrome typically presents with early loss of ovarian function and should be considered when primary ovarian insufficiency is present with apparent absent uterus on imaging. Follow-up imaging of the apparent absent uterus post-estrogen replacement therapy is important to confirm a normal uterus. A diagnosis of an absent uterus can be psychologically traumatic for patients and families, and can have significant implications for future fertility options.

Endocrine complications following pediatric bone marrow transplantation.

Abstract Pediatric bone marrow transplantation (BMT) for various diseases can lead to endocrine system dysfunction owing to preparative regimens involving chemotherapy and radiation therapy. We assessed the prevalence of post-BMT endocrine complications in children treated at the Alberta Children’s Hospital (ACH) from 1991 to 2001. Time of onset of endocrine dysfunction, underlying disease processes, chemotherapy, radiation therapy and age at BMT were characterized. Subjects of <18 years of age at the time of allogeneic or autologous BMT for whom 1-year follow-up through the ACH and a chart were available for review were included in the study. Subjects with a pre-existing endocrine condition were excluded. Of the 194 pediatric BMT procedures performed at the ACH between January 1, 1991 and December 31, 2001, 150 complete charts were available for review. Sixty five subjects received follow-up care at other centers and were excluded. Therefore, a total of 85 subjects were included in the review. The prevalence of endocrine complications identified was: primary hypothyroidism 1.2%, compensated hypothyroidism 7.0%, hyperthyroidism 2.4%, hypergonadotrophic hypogonadism 22.4%, abnormal bone density 2.4%, and secondary diabetes mellitus 1.2%. These findings emphasize the need to screen for endocrine system dysfunction, particularly hypergonadotrophic hypogonadism, in children who have undergone BMT. Children need long-term follow-up so that endocrine complications can be diagnosed and treated promptly.