A toddler with Down syndrome, hypercalcaemia, hypercalciuria, medullary nephrocalcinosis and renal failure

Intractable Vomiting in an 11-Month-Old Boy With Trisomy 21: A Case Report on Abnormal Calcium/Calcinosis/Creatinine in Down Syndrome

Abnormal calcium/calcinosis/creatinine in Down syndrome (ABCD syndrome) is a very rare condition with no clear etiology. In this paper, we describe our clinical encounter with this disease. We report the case of an 11-month-old male infant with Down syndrome (DS) who presented to the hospital with intractable vomiting and decreased oral intake and urine output. The evaluation revealed an acute kidney injury (AKI) and hypercalcemia. Although his AKI improved with intravenous hydration, his hypercalcemia persisted. Extensive studies were notable for an elevated urinary excretion of calcium and bilateral medullary nephrocalcinosis seen on renal ultrasound (US). As a result, he was diagnosed with ABCD syndrome. Dietary calcium restriction was implemented. During his follow-up visit with a pediatric endocrinologist, his serum calcium was found to be normalized. To our knowledge, this is only the seventh case report on ABCD syndrome in the literature.

Hashimoto Thyroiditis and Nephrocalcinosis in a Child with Down Syndrome

Introduction:

Hypothyroidism has been reported to affect renal function and structure. However, the association of hypothyroidism with distal renal tubular acidosis (dRTA) is rarely reported in children.

Case Presentation:

We present a 6-year-boy with Down syndrome admitted in our department due to vomiting, weakness, polyuria, polydipsia, irritability and weight loss in the last few weeks. Investigations revealed features of hypokalemia, metabolic acidosis and alkaline urine consistent with dTRA. Abdominal ultrasound found nephrocalcinosis. In addition, Antithyroid peroxidase antibodies were positive, suggesting an autoimmune background for the pathogenesis of the tubular dysfunction. Treatment for dRTA and hypothyroidism was started and symptomatic improve was noticed.

Conclusion:

dRTA should be excluded in children with autoimmune disorders who develop weakness, polyuria, polydipsia or growth failure. Early diagnosis would reduce long-term complications.

Mild infantile hypercalcemia: diagnostic tests and outcomes

OBJECTIVE

To assess outcome in a cohort of patients with infantile hypercalcemia followed over 3 years.

STUDY DESIGN

Patients (n = 32) presenting to the calcium clinic between July 2002 and September 2008 were studied. In addition to tests of calcium phosphate metabolism, serum insulin-like growth factor-1, calcitonin, urine citrate, and calcium-sensing receptor gene analysis were obtained.

RESULTS

Mean age at presentation was 6.0 ± 6.3 months. Mean calcium level was 11.4 ± 0.7 mg/dL (2.84 ± 0.17 mmol/L). A recognized cause was found in 14% and a probable cause in 14% of the cohort. Those with nephrocalcinosis (n = 11) had significantly lower mean weight SDS and higher mean calcium levels. The biochemical profile of those in whom no cause could be determined included nonsuppressed parathyroid hormone with either normal or increased 1,25(OH)(2)D. Hypercalcemia resolved in 20 patients. However, in approximately a third, there was persistence in hypercalcemia, hypercalciuria, or nephrocalcinosis.

CONCLUSIONS

The addition of 1,25(OH)(2)D and calcium-sensing receptor mutation analysis to a panel of investigations may improve diagnostic yield. Clinical outcome is overall good, however, one-third need ongoing follow-up.

Elevated intracellular calcium in neutrophils in patients with Down syndrome

BACKGROUND

Neutrophils of patients with Down syndrome (DS) are known to have numerous abnormalities associated with diminished resistance to infection. The intracellular calcium (Ca(2+)i) acts as a second messenger and regulates diverse functions in many cell types. The purpose of the present study was to compare the intracellular calcium concentration ([Ca(2+)]i) at baseline and stimulated conditions in DS patients and in normal subjects to investigate [Ca(2+)]i regulation in neutrophils.

METHODS

The study group consisted of 27 subjects with DS (age, 8.6 +/- 4.6 years) and 14 healthy subjects (age, 12.0 +/- 3.9 years). Using a fluorescent probe, fura-2, the baseline levels and changes in [Ca(2+)]i were examined after stimulation of neutrophils with N-formyl-methionyl-leucyl-phenylalanine (fMLP).

RESULTS

At baseline, the [Ca(2+)]i of neutrophils from DS subjects was significantly higher than that of the controls (70.6 +/- 28.0 nmol/L vs 44.4 +/- 16.0 nmol/L, P < 0.01). The absolute [Ca(2+)]i after addition of fMLP in the DS subjects was also significantly higher than that of the control group (250 +/- 91 nmol/L vs 167 +/- 60 nmol/L, respectively: P < 0.01). The neutrophils from the DS subjects had a consistently and significantly prolonged response to fMLP as compared to the neutrophils of control subjects.

CONCLUSIONS

The higher [Ca(2+)]i and the prolonged response of [Ca(2+)]i to fMLP appear to be phenotypic traits of neutrophils in subjects with DS. This suggests intrinsic cellular defects in DS.

The A, B, C, D of hypercalcaemia in Down syndrome

Hypercalcaemia in infants with Down syndrome is an uncommon condition with only five previous case reports. The patients often present in the toddler years with the classical triad of Down syndrome, biochemical hypercalcaemia, and nephrocalcinosis. We present the sixth case and second male with this condition and further review the clinical details of this under-recognised condition and stratify the diagnostic criteria. The management mandates a reduction in calcium intake as a first step. The natural history of the various aspects of this condition is also considered.

Nutrient intake and anthropometry in children and adolescents with Down syndrome--a preliminary study

OBJECTIVE

To assess nutrient intake and anthropometrical characteristics of children and adolescents with DS, in Northern Greece.

STUDY DESIGN

Cross-sectional study of 34 youngsters with DS. The sample was divided into two age groups, children aged 2-9 years and adolescents aged 10-18 years old. A 3-day food record was used to assess dietary intake. Body weight, height, WHR,% body fat, BMI, FMI, FFMI and z-scores were recorded for each participant.

RESULTS

All participants exhibited a high CHO and low fat diet. More than half of the participants reported having five meals daily and the majority exercised twice a week. A great majority was stunted and overweight according to general population growth charts and 22% of the adolescents were also obese. %Body fat, BMI, FMI and FFMI was higher in adolescents. Generally, younger participants presented lower overweight rates and consumed a diet more sufficient in micronutrients; however, WHR was similar in both age-groups, indicating a constant trend in weight distribution of DS patients.

CONCLUSIONS

Although children with DS are born with a genetic predisposition to become overweight, obesity is actually nurtured throughout childhood when they develop food choices and become more independent.

Genetic Hypercalciuria

Hypercalciuria is an important, identifiable, and reversible risk factor in stone formation. The foremost and most fundamental step in dissecting the genetics of hypercalciuria is understanding its pathophysiology. Hypercalciuria is a complex trait. This article outlines the various factors that compromise the attempt to dissect the genetics of hypercalciuria, summarizes the clinical and experimental monogenic causes of hypercalciuria, and outlines the initial results from attempts in studying polygenic hypercalciuria. Finally, the problem is set in perspective of the current database, technologic advances and limitations are highlighted, and prospects of further advances in the field are speculated upon.

Hypercalcaemia in association with trisomy 21 (Down's syndrome)

The combination of hypercalcaemia, hypercalciuria, and nephrocalcinosis with and without renal impairment is rare in paediatric clinical practice. However, this constellation of findings has been reported in three children with trisomy 21, but the absence of detailed nutritional data has failed to clarify the underlying pathogenesis. This report describes a 4 year old girl with trisomy 21 who was found coincidentally to have hypercalcaemia, hypercalciuria, nephrocalcinosis, and renal impairment in the absence of metabolic alkalosis, following a prolonged period of excessive calcium intake.