Maxillomandibular brown tumor--a rare complication of chronic renal failure

We report a 17-year-old hemodialysis patient with a rapidly growing maxillary mass diagnosed as a brown tumor. Although successful control of the parathyroid hormone (PTH) levels was achieved by treatment with vitamin D pulse therapy, the lesion progressed, invaded the maxillary sinus, and caused severe eating and speech disabilities. No recurrence was observed following surgical excision. The differential diagnosis and considerations regarding the causes of the disease in a child, therapy options, and review of the literature are presented.

Search for the decay &Bmacr;(0)-->D(*0)gamma

We report results of a search for the rare radiative decay &Bmacr;(0)-->D(*0)gamma. Using 9.66x10(6) B&Bmacr; meson pairs collected with the CLEO detector at the Cornell Electron Storage Ring, we set an upper limit on the branching ratio for this decay of 5.0x10(-5) at 90% C.L. This provides evidence that the anomalous enhancement is absent in W-exchange processes and that weak radiative B decays are dominated by the short-distance b-->sgamma mechanism in the standard model.

Blood pressure measurements in Israeli Arab children and adolescents

BACKGROUND

Hypertension is one of the most prevalent vascular diseases in the adult population. It is an important determinant of atherosclerosis in adolescents and young adults. There is to date no information on blood pressure in children of the Israeli Arab population.

OBJECTIVES

To study blood pressure in Israeli Arab children and adolescents.

METHODS

Blood pressure measurements were taken in the supine position in 4,488 Israeli Arab children and adolescents of both sexes aged 6-17 years. Height and weight were also determined. Correlation was investigated between systolic and diastolic blood pressure, body mass index, gender, and age.

RESULTS

The systolic and diastolic blood pressures were similar in both sexes for all age groups up to 14 years of age. Systolic blood pressure was significantly (P < 0.001) higher in males aged 15-17 years (120 +/- 13 vs. 111 +/- 12 mmHg, 123 +/- 13 vs. 113 +/- 14.0 mmHg, and 123 +/- 18 vs. 111 +/- 14 mmHg, respectively). Diastolic blood pressure was higher in males aged 15-17, with a statistically significant difference for age 17 only (75 +/- 12 vs. 69 +/- 13 mmHg). Blood pressure was elevated in 322 students in the initial screening (7.17%), with a decrease to 2.18% when this group was rescreened 2 weeks later. The systolic blood pressure in our group is higher than that in Jewish Israeli children of Asian and North African origin, and in American children. It is similar to the systolic blood pressure of European children and Jewish children born in Israel. The diastolic blood pressure in our group is higher than that in all groups of Israeli Jewish children and American children of different ethnic groups.

CONCLUSIONS

Israeli Arab children and adolescents have higher blood pressure levels than their Israeli Jewish counterparts. Further studies are required to confirm this observation.

Low serum C3, leukopenia, and thrombocytopenia: unusual features of henoch-schonlein purpura

Henoch-Schonlein purpura (HSP) affects predominantly the skin, joints, gastrointestinal tract and kidney. Although the pathogenesis is probably of immune origin and complement activation is thought to play a role, laboratory findings including the serum level of the complement components are usually normal. We present a patient with a severe form of HSP nephritis who had unusual laboratory findings of a low level of C3, mild leukopenia and thrombocytopenia. These findings may further support the importance of complement activation in the pathogenesis of HSP.

Genetic polymorphisms of the renin-angiotensin system and the outcome of focal segmental glomerulosclerosis in children

BACKGROUND

The clinical course of primary focal segmental glomerulosclerosis (FSGS) in children is variable, with some patients having a much more rapidly progressing course than others. The purpose of our study was to compare the frequency of three polymorphisms of the renin-angiotensin system (RAS) in children with FSGS with that in healthy controls of matching ethnic groups, and to determine whether the clinical outcome of FSGS was associated with different RAS genotypes.

METHODS

Three RAS genotypes were examined in 47 Jewish and Arab children with biopsy-proven primary FSGS and in a large control group: the ACE insertion/deletion polymorphism in intron 16, the M235T mutation in the angiotensinogen gene, and the A1166C in the angiotensin II type 1 receptor gene (AT1R).

RESULTS

Arab patients showed a greater tendency towards progressive renal disease than their Jewish counterparts (12 of 21 vs. 9 of 26, P = 0.05) and were less likely to achieve remission (3 of 21 vs. 11 of 26, P < 0.04), despite similar clinical presentation, medical management and follow-up. The RAS allele prevalence was similar among patients and controls of matching ethnic backgrounds, and no difference in allele frequency was found between Arabs and Jews. Homozygotes for the ACE insertion genotype (II) were significantly less likely to have progressive renal disease than patients with the other genotypes (ID and DD; 0 of 6 vs. 21 of 41; P < 0.022). The other RAS polymorphisms were not associated with variations in the clinical course of childhood FSGS.

CONCLUSIONS

Homozygosity for the ACE insertion allele may have a protective effect in children with FSGS and can serve as a positive prognostic indicator at diagnosis. The D allele may exert a detrimental dominant effect on outcome. Neither the ACE gene polymorphism nor the other RAS polymorphisms studied are associated with disease prevalence. The AT1R and angiotensinogen gene polymorphisms are not associated with progression of renal disease in FSGS. Ethnic differences in the clinical course of the disease are not linked to these polymorphisms.

Renal functional reserve after acute poststreptococcal glomerulonephritis

We evaluated renal functional reserve (RFR) in 36 patients aged 5-21 years, who had recovered from an acute episode of poststreptococcal glomerulonephritis (PSGN) 1-16 years previously, without apparent sequelae, as evidenced by normal serum creatinine, blood pressure, and urinary sediment. The control group consisted of 12 children aged 2-12 years with recurrent urinary tract infections or nocturnal enuresis, without active infection or anatomical anomalies. The basal creatinine clearance was similar in the PSGN and control groups: 140.0 +/- 27.4 ml/ min per 1.73 m2 and 142.9 +/- 15.5 ml/min per 1.73 m2, respectively. The RFR in the PSGN group was significantly reduced compared with that of the control group: 18.6 +/- 12.9 ml/min per 1.73 m2 and 41.1 +/- 25.3 ml/min per 1.73 m2, respectively (P < 0.02). In 7 PSGN patients (19.4%), no RFR was found. In 69% of patients who had recovered from PSGN more than 10 years before the protein loading tests, a significantly reduced RFR (less than 10% of baseline) was found. The same degree of reduction in RFR was found in only 26% of patients who had suffered from PSGN less than 10 years ago.

Renal function in full-term neonates with hyperbilirubinemia

The purpose of this study was to investigate the effect of unconjugated hyperbilirubinemia on endogenous creatinine clearance and urinary excretion of sodium, phosphorus, lysozyme, and amino acids in full-term infants. Thirty-seven healthy, breast-fed newborns who were not exposed to phototherapy were studied on their third to fifth day of life. Twenty had neonatal hyperbilirubinemia with a mean indirect bilirubin value of 16.4 mg/dl, whereas 17 who were used as controls had a mean indirect bilirubin value of 7.8 mg/dl. Urine was collected, and samples were taken for examination of creatinine, lysozyme, sodium, and phosphorus concentration. Urinary sediment, glucose, and amino acid levels were also measured. Serum total and direct bilirubin, creatinine, sodium, and phosphorus measurements were taken at the beginning of urine collection. Calculations were made for creatinine clearance, fractional excretion of sodium (FENa), and tubular reabsorption of renal phosphate per deciliter glomerular filtrate (TP/GFR). The means (+/-1 SD) of creatinine clearance, FENa, and TP/GFR were 27.0 +/- 14.2 ml/min/1.73 m2, 0.53% +/- 0.49%, and 5.72 +/- 1.16 mg/dl GF, respectively, in the hyperbilirubinemic group compared with 21.1 +/- 9.4 ml/min/1.73 m2, 0.4% +/- 0.47%, and 6.01 +/- 0.51 mg/dl GF, respectively, in the controls. No statistically significant differences were found between the groups for any of the examined parameters of either glomerular or tubular function. Neonatal hyperbilirubinemia < 20.8 mg/dl has no detrimental effect on renal function of healthy, breast-fed, full-term newborns, and no modification in the approach regarding renal function is necessary in these babies.

Integration host factor stimulates both FimB- and FimE-mediated site-specific DNA inversion that controls phase variation of type 1 fimbriae expression in Escherichia coli

The site-specific DNA inversion that controls phase variation of type 1 fimbriation in E. coli is catalysed by two recombinases, FimB and FimE. Efficient inversion by either recombinase also requires the leucine-responsive regulatory protein (Lrp). In addition, FimB recombination is stimulated by the integration host factor (IHF). The effect of IHF on FimE inversion has not previously been reported. Here it is shown that IHF stimulates FimE recombination; In strain MG1655, mutants containing lesions in either the alpha (ihfA) or beta (ihfB) subunits of IHF show a marked decrease in both FimB- (100-fold) and FimE (15,000-fold)-promoted switching. IHF is shown to bind with high affinity to sites both adjacent to (site I) and within (site II) the fim invertible element. Furthermore, mutations in site I or site II that lower the affinity of IHF binding In vitro were found to lower the frequency of FimE and/ or FimB recombination in vivo. Although site I and site II mutations in combination have an effect on FimB-promoted switching comparable to that of IHF knockout mutations (100-fold), the cis site mutations have a much less marked effect (100-fold) on FimE-promoted switching.

Growth hormone treatment increases circulating lipoprotein(a) in children with chronic renal failure

Cardiovascular disease is the major cause of death in chronic renal failure (CRF) patients managed by dialysis or kidney transplantation. Whilst the use of human growth hormone (hGH) is of established benefit in CRF children particularly in those with short stature, in the present study we assessed in CRF children the effect of hGH treatment on circulating lipoprotein(a) [Lp(a)], a genetically determined cardiovascular risk factor. We studied 15 CRF children treated by dialysis or conventional therapy and after kidney transplantation. Overnight fasting blood samples were collected immediately before and after 6 months hGH treatment. In all but one of the children there was a significant increase in serum Lp(a) over the 6 month treatment period -(+)66.7% over the basal levels (range 14 to 180%). After the hGH treatment, in six children Lp(a) levels were elevated to above 300 mg/l, the cut-off level for increased coronary artery disease (CAD) risk. Concomitantly/children also had an increase in serum levels of IGF-I (+96.4%) and insulin (+85.8%). All children had an accelerated growth velocity during the treatment; there was no effect on serum creatinine. Our study shows that hGH treatment in CRF children, though beneficial in its growth promoting effects, increases the already characteristically high levels of serum Lp(a), a risk factor for CAD, and that serum Lp(a) monitoring during treatment with hGH may be useful in evaluating future cardiovascular risk.