Asymptomatic kidney stones in long-term survivors of childhood acute lymphoblastic leukemia

We hypothesized an association between renal calculi and bone mineral density (BMD) deficits, shown in adults, exists in survivors of childhood acute lymphoblastic leukemia (ALL). Thus, we analyzed the associations between quantitative computed tomography (QCT)-determined renal calcifications and clinical parameters (gender, race, age at diagnosis and age at the time of QCT), BMD, treatment exposures and Tanner stage. We investigated the associations between stone formation and nutritional intake, serum and urinary calcium and creatinine levels, and urinary calcium/creatinine ratio. Exact chi(2)-test was used to compare categorical patient characteristics, and the Wilcoxon-Mann-Whitney test to compare continuous measurements. Of 424 participants, 218 (51.4%) were males; 371 (87.5%) were nonblack. Most (n=270; 63.7%) were >or=3.5 years at ALL diagnosis. Mean (s.d.) and median (range) BMD Z-scores of the entire cohort were -0.4 (1.2) and -0.5 (-3.9 to 5.1), respectively. Nineteen participants (10 males; 10 Caucasians) had kidney stones (observed prevalence of 4.5%; 19/424) with a significant negative association between stone formation and body habitus (body mass index, P=0.003). Stone formation was associated with treatment protocol (P=0.009) and treatment group (0.007). Thus, kidney stones in childhood ALL survivors could herald the future deterioration of renal function and development of hypertension. Long-term follow-up imaging may be warranted in these patients to monitor for progressive morbidity.

Antipyretic efficacy and tolerability of a single intravenous dose of the acetaminophen prodrug propacetamol in children: a randomized, double-blind, placebo-controlled trial

BACKGROUND

Propacetamol is an acetaminophen prodrug that was available in Europe as an IV formu lation for the treatment of pain and fever for some time. One gram of propacetamol is hydrolyzed in blood to release 0.5 g of acetaminophen and pharmacologically inactive N,N-diethylglycine.

OBJECTIVE

This study compared the antipyretic efficacy and tolerability of IV propacetamol and placebo after a single administration in children with acute fever of infectious origin. The study was performed in anticipation of an application for US registration.

METHODS

This was a double-blind, placebo-controlled trial in which patients with a body temperature (tympanic probe) of 38.5 degrees C to 41 degrees C were randomized to receive propacetamol 30 mg/kg IV or a placebo of identical appearance, both administered as 15-minute infusions. Temperature was measured at baseline, 0.5 hour after drug administration, and hourly thereafter for 6 hours or until use of rescue medication. The primary efficacy variable was the change in body temperature at each evaluation time compared with baseline. Secondary efficacy variables included the number of children requiring rescue medication and the time to remedication; the number of children with a body temperature <38 degrees C during the evaluation period and the time to reach this temperature; maximal body temperature reduction; and the weighted sum of changes in body temperature over the evaluation period. Tolerability was assessed based on changes in vital signs, monitored for 6 hours after administration of study drug, and adverse events recorded during the 24 hours after administration.

RESULTS

Twenty children received propacetamol and 21 received placebo. Twenty patients were white, 17 black, and 4 Hispanic; their age ranged from 3 to 12 years. The actual mean (SD) dose of propacetamol received was 25.5 (0.6) mg/kg (equivalent to acetaminophen 12.8 [0.3] mg/kg). The reduction in body temperature was significantly greater in the propacetamol group compared with the placebo group at each time point over the 6-hour follow-up period (P < 0.001). Rescue medication was administered to 10.0% of patients in the propacetamol group, compared with 52.4% of those in the placebo group (P = 0.004). The weighted mean (SD) sum of the change in body temperature indicated greater antipyretic efficacy for propacetamol compared with placebo (-7.9 [3.8] degrees C x h vs 0.1 [3.6] degrees C x h, respectively; P < 0.001). There was no difference in the number of patients with treatment-emergent adverse events in the propacetamol and placebo groups (8 [40.0%] and 8 [38.1%]). The incidence of IV-site reactions was 10.0% in the propacetamol group and 9.5% in the placebo group.

CONCLUSIONS

In these 41 children with acute fever of infectious origin, a propacetamol dose of 25.5 (0.6) mg/kg IV had significantly greater antipyretic efficacy than placebo and was equally well tolerated. Comparisons of this preparation with other IV antipyretic medications are needed.

Calciuria and aminoaciduria in very low birth weight infants fed a high-mineral premature formula with varying levels of protein

To assess the influence of protein intake on renal excretion of calcium and amino acids and on bone mineralization in preterm infants, we randomly selected within weight group strata 27 infants who weighed < 1500 gm at birth (nine per group) to be fed a high-mineral (calcium, 940 mg/L; phosphorus, 470 mg/L) premature formula with one of the following protein contents: formula A, 3.0 gm/100 kcal; formula B, 2.7 gm/100 kcal; and formula C, 2.2 gm/100 kcal. Mean (+/- SD) daily weight gain was greater in infants receiving the higher protein intakes for the first 30 days (formula A, 24.8 +/- 5.1 gm; formula B, 20.5 +/- 3.8 gm; formula C, 16.2 +/- 5.9 gm (analysis of variance: p < 0.01; C < A, p < 0.05)). Bone mineral content did not differ at any time point, and all groups had a high prevalence of generalized aminoaciduria (4 weeks: formula A, 56%; formula B, 71%; formula C, 75%). Urinary calcium corrected for creatinine (in milligrams per milligram) increased as protein content decreased (2 weeks: formula A, 0.16 +/- 0.10; formula B, 0.20 +/- 013; formula C, 0.44 +/- 0.33 (C > A, C > B, p < 0.05); 4 weeks: formula A, 0.23 +/- 0.15; formula B,0.34 +/- 0.47; formula C, 0.49 +/- 0.22 (C > A, p < 0.01). We conclude that the high mineral content and other components of premature formulas result in a higher growth rate and may increase protein requirements. Failure to meet protein requirements may result in underutilization of absorbed calcium and increased renal excretion of calcium. In preterm infants, higher protein intake probably supports rather than jeopardizes bone mineral accretion, and reduces rather then increases calciuria.

Vitamin D and mineral metabolism in the very low birth weight infant receiving 400 IU of vitamin D

STUDY OBJECTIVE

To examine (1) the effect of vitamin D intake (380 to 480 IU daily) on plasma 25-hydroxyvitamin D (25-OHD) and 1,25-dihydroxyvitamin D (1,25-(OH)2D) concentrations and (2) the relationship of 1,25-(OH)2D to calcium and phosphorus absorption and retention in the very low birth weight infant receiving a preterm infant formula.

SUBJECTS

Eleven "well" infants with a birth weight and gestational age (mean +/- SD) of 1078 +/- 128 gm and 29 +/- 1.9 weeks, respectively, were studied for a 3-week period. Weight and postnatal age (mean +/- SD) at the beginning of the study were 1132 +/- 56 gm and 16 +/- 6 days, respectively. All infants were fed a preterm infant formula and tolerated a full enteral intake (120 kcal/kg/day) for the duration of the study.

INTERVENTIONS

Plasma 25-OHD and 1,25-(OH)2D concentrations were measured at the beginning of the study and at the beginning of each 48-hour balance period. Calcium and phosphorus balance studies (n = 33) were performed weekly.

MAIN RESULTS

Plasma 25-OHD (30 +/- 10 ng/ml) and 1,25-(OH)2D (54 +/- 14 pg/ml) concentrations were normal at the beginning of the study. Plasma 25-OHD values did not change, but 1,25-(OH)2D values increased (p less than 0.001) throughout the study. Plasma 1,25-(OH)2D concentrations were not related to calcium or phosphorus absorption and retention, but were a linear function of postconceptional age.

CONCLUSIONS

Normal vitamin D status and activity are maintained in the very low birth weight infant fed a high calcium formula (380 to 480 IU of vitamin D daily). Plasma 1,25-(OH)2D concentrations are not related to calcium absorption but are linearly related to maturity.

Cyclic AMP does not alter taurine accumulation by rat renal brush border membrane vesicles

Secondary hyperparathyroidism has been attributed to be responsible for the generalized aminoaciduria and phosphaturia of vitamin D deficiency. Since PTH acts in the kidney to generate cAMP, we explored the possibility that its synthetic analog, dbcAMP, would alter the renal transport of taurine (an amino acid lost in the urine in vitamin D deficiency) and Pi. Exposure of renal BBMV prepared from normal and vitamin D-calcium-deficient rats to dbcAMP at concentrations ranging between 10(-4) and 10(-7) M did not alter taurine uptake by these vesicles. Higher dbcAMP concentrations blunted uptake, but these concentrations reduced intravesicular volume, thus representing an artifact of osmolarity. Preincubation of BBMV with dbcAMP for times between 0 and 60 min at 0 or 25 degrees C also did not alter taurine accumulation. Hypotonic lysis of BBMV, allowing entry of the cyclic nucleotide, followed by isotonic resealing did not influence taurine uptake. The addition of potassium fluoride (to inhibit phosphodiesterase activity) and ATP (as an energy source) did not alter taurine accumulation at 60 sec. The uptake of Pi, which is influenced by PTH, was decreased by 25% following exposure to dbcAMP on the internal surface of the vesicle. These data indicate that the taurinuria observed in vitamin D deficiency is unlikely to be related to a PTH-induced increase in intracellular cAMP, unlike the changes in Pi transport, which is sensitive to cyclic nucleotides.

Course of nephropathic cystinosis after age 10 years

We identified 80 patients with nephropathic cystinosis older than age 10 years in the United States and Canada. The oldest reported individual was 26 years of age. Ninety percent of patients had received at least one renal allograft. Age at the time of first transplant varied between 7 and 17 years (mean 10.0 years). Almost three fourths of the patients required thyroid replacement, 27% had splenomegaly, and 42% had hepatomegaly. Photophobia was noted in 86% of patients, decreased visual acuity in 32%, and corneal ulcerations in 15%. Neurologic involvement, renal osteodystrophy, and diabetes mellitus were unusual. All these late complications of nephropathic cystinosis contribute to a description of the natural history of the disease and provide a rationale for the therapeutic use of cystine-depleting agents after renal transplantation.

Urologic implications of the VATER association

Among 23 children with the VATER association 21 had significant genitourinary involvement. The extent of these genitourinary anomalies is not generally appreciated. The principal renal anomalies were renal agenesis (7 cases), ureteropelvic junction obstruction (5 cases), crossed fused ectopia (5 cases) and severe reflux (9 cases). Since corrective urologic surgery is commonly beneficial for children with the VATER association, an early and appropriate urologic evaluation is indicated.

Fanconi's syndrome in renal transplantation

An association between Fanconi's syndrome and renal transplantation has been reported. We report a patient who developed Fanconi's syndrome coinciding with a rejection episode 4.5 years following living related donor transplantation. Recurrent disease and hyperparathyroidism were ruled out as etiologies of Fanconi's syndrome. The presence of Fanconi's syndrome--associated with rejection in the transplanted kidney--may signify immunologically mediated alterations in tubular function. Antitubular basement membrane antibodies have been reported in renal allograft recipients. Further study into the pathogenesis of Fanconi's syndrome in renal transplantation may shed light on the spectrum of immunologically mediated dysfunction following renal homotransplant.

Gene D5 product of bacteriophage T5: DNA-binding protein affecting DNA replication and late gene expression

Gene D5 is not only necessary for replication of bacteriophage T5 DNA and for shutoff of expression of some early genes, but has been found to be necessary also for the expression of late T5 genes. The polypeptide product of gene D5 has been identified, an intragenic map of gene D5 has been constructed, and the direction of transcription of gene D5 has been established. The polypeptide coded by gene D5 has been shown to be a DNA-binding protein with affinity for both double- and single-stranded DNA.

Growth and glucocorticoids in children with kidney disease

Glucorticoid therapy inhibits statural growth. Alternate-day therapy causes less growth suppression than does daily therapy, and, in experimental animals and children with asthma, it has been associated with normal growth. Although catch-up growth may occur after cessation of steroid therapy, this is not always the case, especially when therapy has been prolonged. In children treated with steroids for glomerulonephritis or nephrotic syndrome and especially in children after renal transplantation, factors other than steroid therapy may contribute to growth retardation. Steroids may suppress growth by direct action on cell metabolism, by inhibition of growth hormone or somatomedin and/or by effects on calcium and phosphorus metabolism. Present knowledge of mechanisms of action and dose-response relationships is complete, and it is difficult to prescribe therapy which will achieve a predictable therapeutic effect without inhibiting growth.

Induction of suppressor T cells in systemic lupus erythematosus by thymosin and cultured thymic epithelium

Patients with systemic lupus erythematosus lacked suppressor T cell function. Suppressor cell activity was induced in cells from many of these patients by incubation with thymosin or cultured thymic epithelium. These results suggest that thymic manipulation may be a useful therapeutic modality in this disease.

[Urologic symptoms in the abdominal muscle deficiency syndrome (author's transl)]

The abdominal muscle deficiency syndrome ("prune belly syndrome"(, a symptom triad of aplasia of the abdominal wall musculature, malformations of the urinary tract, and cryptorchism, is described from the urologist's point of view, citing nine cases. With modern diagnostic procedures the early detection of the correct diagnosis in the usually very young patients is possible. While the urologic symptomatology is due to the malformations in the urinary tract, the life expectancy depends mainly on the degree of renal function impairment. Combat of infection together with proper operative repairs are the treatments of choice to date. Instrumental procedures should be limited as much as possible. The survival changes following kidney transplantation appear promising.