Osteogenesis imperfecta in childhood: perceived competence in relation to impairment and disability

OBJECTIVES

To examine the perceived competence of children with different types of osteogenesis imperfecta (OI) and to investigate the possible relationships between their perceived competence and impairment parameters.

DESIGN

Cross-sectional study.

SETTING

National referral center (hospital) for the treatment of children with OI.

PATIENTS

Forty children with OI (type I = 17; type III = 11; type IV = 12) with a mean age +/- standard deviation of 12.6 +/- 3.2 years.

INTERVENTIONS

Measured joint range of motion (ROM) in the upper extremities (UEs), and lower extremities (LEs), muscle strength, functional skills, ambulation, and perceived competence.

MAIN OUTCOME MEASURES

Joint ROM in UE and LE; muscle strength (using the manual muscle testing criteria of the Medical Research Council); functional skills using the Pediatric Evaluation of Disability Inventory in 3 domains (self-care, mobility, social function). Ambulation (according to Bleck and classified as nonwalking, therapy walking, household walking, neighborhood walking, community walking with or without the use of crutches), and perceived competence (using the Harter Self-Perception Profile for Children, which was cross-culturally validated for Dutch children).

RESULTS

In children with type I, joint ROM and muscle strength were almost comparable to the healthy population. In children with type III, a severe decrease in joint ROM was measured, especially in the LEs, and muscle strength was severely decreased in the UEs and LEs. In children with type IV, joint ROM and muscle strength decreased, especially in the LEs. In all types, fairly to strongly positive perceived competence was measured except for fairly negative perceived competence in the athletic performance subscale in type I and a fairly negative perceived competence in the romance subscale in type III. No correlations were found between (1) joint ROM and athletic performance and physical appearance, (2) muscle strength and athletic performance or physical appearance, or (3) the functional skills, concerning self-care and mobility, with the subscales of the perceived competence.

CONCLUSIONS

Although joint ROM, muscle strength, and functional and walking ability were related to the severity of the disease and differed significantly between the different types of OI, overall perceived competence in children with OI was fairly to strongly positive, without significant differences between the different types of OI.

Control of blood pressure in the ambulatory setting

Control of blood pressure still relies on conventional office or clinical blood pressure measurement using mercury sphygmomanometry. However, it has long been known that office measurement, even when repeated, does not fully reflect usual blood pressure. The additional use of ambulatory devices for prolonged periods of blood pressure measurement is now clinically feasible. Previous research has indicated that ambulatory blood pressure measurement is better than office measurement at predicting individual cardiovascular risk. Guidelines for clinical use of ambulatory blood pressure measurement and for quality control of devices are available. Ambulatory measurement has revealed characteristics of circadian rhythm and variability that are promising with regard both to improving our understanding of the aetiology of high blood pressure and to individual risk assessment. Some of the latest developments in research on ambulatory blood pressure measurement are discussed.

Does the empiric use of vancomycin in pediatrics increase the risk for Gram-negative bacteremia?

BACKGROUND

Gram-negative bacteremia in children, a major cause of morbidity and mortality, may in part be induced by intensive treatment procedures and nonspecific use of antibiotics. Our primary objective was to study the causal relationship between the use of vancomycin and Gram-negative bacteremia, for which this antibiotic is not specifically indicated.

METHODS

The study was conducted in a 105-bed tertiary care children's hospital in the period of 1994 to 1997. The study pertains to a cohort of children with suspected bacteremia, in whom a blood culture was performed during hospital stay. Using the bacteriologic laboratory registration system, we selected all pediatric cases with bacteriologically proved Gram-negative bacteremia (n = 105) and a random sample of 225 pediatric controls with negative blood cultures. Using logistic regression analysis we examined associations between Gram-negative bacteremia and the following factors: preceding use of antibiotics, antacids, corticosteroids, surgery, mechanical ventilation, parenteral nutrition, and invasive instrumentation; and the intensity of care assessed with the Therapeutic Intensity Scoring System (TISS 28).

RESULTS

Gram-negative bacteremia was positively associated with the use of aminoglycosides, cephalosporins, surgical interventions, central venous catheters, parenteral nutrition, antacids and dexamethasone. The strongest association was with the use of vancomycin (odds ratio, 8.1; 95% confidence interval, 3.1 to 20.9). In a multiple logistic regression model containing all above-mentioned variables, the use of vancomycin remained positively and strongly associated with Gram-negative bacteremia (odds ratio, 3.88; 95% confidence interval, 1.34 to 11.21). Further adjustments and restrictions in the analysis did not materially change these findings concerning vancomycin.

CONCLUSIONS

Among children suspected of bacteremia there are several drugs and clinical procedures influencing the risk for Gram-negative bacteremia. Empiric use of vancomycin is strongly and independently associated with Gram-negative bacteremia. The safety of using vancomycin solely on the basis of suspicion of bacteremia in children may not be warranted.

Low-dose dopamine in neonatal and pediatric intensive care: a systematic review

OBJECTIVES

To assess the current use of low-dose dopamine (< 5 microg/kg per minute) to improve renal function and urine volume (UV) in neonatal (NICU) and pediatric (PICU) intensive care units, and to assess the available evidence to support this practice.

DESIGN

A written survey was used to assess the current use of low-dose dopamine among all 19 NICUs and PICUs in the Netherlands. In addition, a review of the literature of clinical intervention studies in which low-dose dopamine was administered to improve renal function and UV was performed.

METHODS

The clinical intervention studies focused on preterm neonates, critically ill infants and children, and those who underwent cardiac surgery. Either creatinine clearance or glomerular filtration rate and increase in UV were used to measure renal function improvement.

RESULTS

Our survey showed that among the 19 NICUs and PICUs, dopamine is regularly used either to improve renal function (n = 7) or to enhance UV (n = 13). The literature review identified seven clinical studies. Of these only one was a randomized controlled trial in preterm neonates, and this showed no positive correlation between renal function and UV. The other studies were uncontrolled experiments in preterm infants that claimed positive effects on UV (n = 5) and creatinine clearance (n = 2).

CONCLUSIONS

The widespread use today of low-dose dopamine in Dutch NICUs and PICUs is not supported in the literature. Evidence from well performed clinical studies to support the use of low-dose dopamine for improving renal function and UV in critically ill neonates and children is largely insufficient. In view of adverse effects, the use of low-dose dopamine in neonatal and pediatric intensive care patients should be reconsidered.

Ectopic ureterocele: results of open surgical therapy in 40 patients

PURPOSE

The treatment of ectopic ureterocele is controversial. In addition to debate on optimal therapy, discussion exists on whether there is further risk of deteriorating bladder function after extensive bladder surgery during the first year of life, which is a reason to postpone surgery. In a prospective nonrandomized trial we treated 40 patients regardless of age who had ectopic ureterocele with complete surgical reconstruction of the lower urinary tract and upper pole resection of poorly functioning upper pole moieties at referral. Excluded from study were 3 patients with only 1 affected renal moiety initially.

MATERIALS AND METHODS

We treated 31 female and 9 male patients 0 to 8.8 years old (mean age 2.17) at surgery for ectopic ureterocele extending into the bladder neck and urethra, including 19 younger than 1 year. Primary ureterocele excision was performed in 37 cases with reconstruction of the urethra, bladder neck and trigone, and ureteral reimplantation. Because of small ureterocele size, the ureterocele was left in situ in 3 patients, leading to secondary ureterocele removal due to obstructive voiding and urinary incontinence in 1 each. A staged procedure in 5 neonates involved primary lower urinary tract reconstruction with upper pole cutaneous ureterostomies followed by upper pole resection or ureteral reimplantation a few months later. After bladder neck reconstruction in 16 cases colposuspension was also done to create a normal vesicourethral angle. All patients underwent clinical and urodynamic evaluation at least 1.25 years after surgery (mean followup 5.59). Patients who were too young for the clinical assessment of continence by January 1999 were excluded from study.

RESULTS

All patients are continent. A secondary endoscopic procedure was required in 13 cases, including cystoscopy only in 2, scar incision near the ureteral orifice in 3, endoscopic reflux treatment in 4, ureterocele remnant resection in 2 and bladder neck incision for obstructive voiding in 2. Secondary open bladder reconstruction was performed in another case due to a diverticulum. Postoperatively only 1 or 2 uncomplicated episodes of urinary tract infection developed in 11 patients, while there were recurrent urinary tract infections in 4. In a patient with a preexisting loss of renal function a severe infection led to renal scarring. The voiding pattern was normal in 29 patients but 11 had dysfunctional voiding, including 5 with recurrent urinary tract infection. Urodynamic followup confirmed these clinical findings. Bladder capacity in these patients was relatively high at an average of 124% of expected capacity for age. We noted no statistically significant difference in followup parameters in patients who underwent surgery before and after age 1 year. Additional colposuspension in 16 patients did not result in any significant change in outcome compared with that in patients without this procedure.

CONCLUSIONS

When compared with results in the literature, complete primary lower urinary tract reconstruction in patients with ectopic ureterocele appears to have better results than a staged approach with initial endoscopic treatment. Moreover, our study provides no proof that extensive reconstructive bladder surgery in neonates and infants leads to bladder function deterioration at a later age.

Osteogenesis imperfecta in childhood: prognosis for walking

OBJECTIVES

We studied the predicted value of disease-related characteristics for the ability of children with osteogenesis imperfecta (OI) to walk.

STUDY DESIGN

The severity of OI was classified according to Sillence. The parents were asked to report the age at which the child achieved motor milestones, the fracture incidence, and the age and localization of the first surgical intervention. The present main means of mobility was classified according to Bleck.

RESULTS

There were 76 replies to the 98 questionnaires, of which 70 were included (type I, 41; type III, 11; type IV, 18). The type of OI was strongly associated with current walking ability, as was the presence of dentinogenesis imperfecta. Patients with type III and IV had a lower chance of ultimately walking compared with those with type I. Children with more than 2 intramedullary rods in the lower extremities had a reduced chance of walking than patients without rods. Rolling over before 8 months, unsupported sitting before 9 months, the ability to get in sitting position without support before 12 months, and the ability to get in a standing position without support before 12 months showed positive odds ratios. In Bleck > or = 4, multivariate analysis revealed that only the presence of rodding (yes/no) in the lower extremities had additional predictive value to the type of OI. The presence of dentinogenesis imperfecta and rodding (yes/no) had additional value in Bleck > or = 5.

CONCLUSION

The type of OI is the single most important clinical indicator of the ultimate ability to walk. Information about motor development adds little. The early achievement of motor milestones contributes to the ability of independent walking when the type of OI is uncertain. Intramedullary rodding of the lower extremities is primarily related to the severity of the disease and in this way provides consequences for the ability to walk.

Osteogenesis imperfecta: profiles of motor development as assessed by a postal questionnaire

This study was performed to achieve more detailed information regarding the age and sequence in the development of motor milestones in the different types of osteogenesis imperfecta (OI). The parents of 98 patients with a diagnosis of OI were sent a questionnaire regarding the age at which patients achieved motor milestones. All patients were attending the outpatient clinic for children with OI at the Wilhelmina Children's Hospital. The motor milestones were classified into static motor milestones and dynamic motor milestones and all data were checked with health care records. The age of development of motor milestones was compared to reference values of the healthy population. The severity of the disease was classified according to Sillence based on clinical, genetic and radiological data. The age of intramedullary rodding of the first nail in the lower and upper extremity and the localisation was noted. A total of 76 parents responded to the 98 questionnaires (78%). In OI type I, a delay exists in achieving motor milestones, comparable to the 95th percentile of the normal population. In type III, the development of all motor milestones was significantly delayed compared to types I and IV with a discrepancy between static and dynamic milestones. In OI type IV, a retardation in motor development developed after the milestone 'sitting without support' was achieved. Motor development in types I and IV was not influenced by intramedullary rodding of the lower extremities, since rodding was rarely performed before the milestone 'unsupported standing' was achieved. In type III, the influence of intramedullary rodding on the age of achieving motor milestones remains questionable.

CONCLUSION

The severity of osteogenesis imperfecta has a large influence on the age and sequence in the development of motor milestones. No influence of intramedullary rodding of the lower extremities on motor development was found in osteogenesis imperfecta types I and IV, whereas the influence in type III remains questionable.

[Increase of reported HIV-1 infections in children in Netherlands, 1982-1997: more vertical transmission and a greater proportion of other than Dutch children]

OBJECTIVE

To document the trend of the yearly number of newly diagnosed paediatric HIV-1 infections in the Netherlands.

DESIGN

Retrospective registration regarding the period January 1st 1982-December 31st 1994 and prospective registration regarding January 1st 1995-December 31st 1997.

METHOD

Based on reports to the Dutch Paediatric Surveillance Unit (Nederlands Signaleringscentrum Kindergeneeskunde) numbers of paediatric HIV-1 diagnoses (0-18 years) in the Netherlands were determined prospectively. Retrospective figures were determined by asking the paediatricians also to report the HIV-1 infected children diagnosed before the first of January 1995. A comparison was made with data from the Inspectorate for Health Care (Inspectie voor de Gezondheidszorg). All reports were followed up with standard questionnaires.

RESULTS

In both periods an increase in the number of newly diagnosed paediatric HIV-1 infections per year in the Netherlands was seen (1982-1994: 74 children; 1995-1997: 43 children). The majority of the parents of the HIV-1 infected children originated from outside the Netherlands (1982-1994: 57%; 1995-1997: 91%), often from HIV-endemic countries (1982-1994: 41%; 1995-1997: 77%). The main mode of infection was vertical transmission (1982-1994: 62%; 1995-1997: 84%); diagnosis in allochtonous children was made relatively late.

CONCLUSION

The current rise in the absolute number of newly detected paediatric HIV-1 infections in the Netherlands is predominantly due to the growing group of children born to parents who originate from HIV-endemic countries.

Birth weight, growth, and blood pressure: an annual follow-up study of children aged 5 through 21 years

Associations between birth weight and blood pressure have been found in children and adults. In this longitudinal study, the objective was to assess the relation between birth weight and blood pressure level and the change in blood pressure from childhood and young adolescence into adulthood. A cohort of 483 children from a middle-class community in the town of Zoetermeer in the Netherlands had annual measurements of blood pressure during an average follow-up period of 14 years. For 330 of these participants, initially aged 5 through 21 years, birth weight data were collected, which were related to blood pressure level and blood pressure change. An inverse association between birth weight and systolic blood pressure was found, with adjustment for current body height and weight, sex, and use of alcohol, cigarettes, and oral contraceptives. This inverse association was found for the total follow-up in 5- to 37- year-olds (regression coefficient: -2.4 mm Hg/kg; 95% confidence interval: -3.9 to -1.0, as well as in most individual age groups: 5 through 9 years (-0.6 mm Hg/kg, -3.2 to 2.0); 10 through 14 years (-2.5 mm Hg/kg, -4.7 to -0.4); 15 through 19 years (-3.1 mm Hg/kg, -4.9 to -1.2); 20 through 24 years (-2.7 mm Hg/kg, -4.6 to -0.9); 25 through 29 years (-2.0 mm Hg/kg, -3.9 to -0.01); and 30 through 37 years (-1.9 mm Hg/kg, -4.6 to 0.7). For diastolic blood pressure, there appeared to be an inverse association with birth weight in the age group of 30 through 37 years, both unadjusted (-2.0 mm Hg/kg, -4.6 to 0.5) and adjusted for risk factors other than sex (-2.3 mm Hg/kg, -4.7 to 0.1), although these findings were of borderline statistical significance. The results were independent of gestational age and were similar in the group of subjects with low birth weight but normal gestational age (-2.7 mm Hg/kg, -4.3 to -1.0). In relation to systolic blood pressure, birth weight showed a significant interaction with body mass index (regression coefficient, 0.02; SE=0.01; P=.05). There was no relation between birth weight and change in systolic or diastolic blood pressure with age. Our longitudinal study shows that birth weight is consistently inversely associated with systolic blood pressure level from childhood to young adulthood and with diastolic blood pressure in young adulthood. Birth weight is not related to change of blood pressure with increasing age. Low birth weight in combination with high current body mass index seems to be of particular importance in the development of high blood pressure.

Plasma homocysteine as a risk factor for vascular disease. The European Concerted Action Project

CONTEXT

Elevated plasma homocysteine is a known risk factor for atherosclerotic vascular disease, but the strength of the relationship and the interaction of plasma homocysteine with other risk factors are unclear.

OBJECTIVE

To establish the magnitude of the vascular disease risk associated with an increased plasma homocysteine level and to examine interaction effects between elevated plasma homocysteine level and conventional risk factors.

DESIGN

Case-control study.

SETTING

Nineteen centers in 9 European countries.

PATIENTS

A total of 750 cases of atherosclerotic vascular disease (cardiac, cerebral, and peripheral) and 800 controls of both sexes younger than 60 years.

MEASUREMENTS

Plasma total homocysteine was measured while subjects were fasting and after a standardized methionine-loading test, which involves the administration of 100 mg of methionine per kilogram and stresses the metabolic pathway responsible for the irreversible degradation of homocysteine. Plasma cobalamin, pyridoxal 5'-phosphate, red blood cell folate, serum cholesterol, smoking, and blood pressure were also measured.

RESULTS

The relative risk for vascular disease in the top fifth compared with the bottom four fifths of the control fasting total homocysteine distribution was 2.2 (95% confidence interval, 1.6-2.9). Methionine loading identified an additional 27% of at-risk cases. A dose-response effect was noted between total homocysteine level and risk. The risk was similar to and independent of that of other risk factors, but interaction effects were noted between homocysteine and these risk factors; for both sexes combined, an increased fasting homocysteine level showed a more than multiplicative effect on risk in smokers and in hypertensive subjects. Red blood cell folate, cobalamin, and pyridoxal phosphate, all of which modulate homocysteine metabolism, were inversely related to total homocysteine levels. Compared with nonusers of vitamin supplements, the small number of subjects taking such vitamins appeared to have a substantially lower risk of vascular disease, a proportion of which was attributable to lower plasma homocysteine levels.

CONCLUSIONS

An increased plasma total homocysteine level confers an independent risk of vascular disease similar to that of smoking or hyperlipidemia. It powerfully increases the risk associated with smoking and hypertension. It is time to undertake randomized controlled trials of the effect of vitamins that reduce plasma homocysteine levels on vascular disease risk.

Families and natural history of lipids in childhood: an 18-year follow-up study

The natural history of total cholesterol and lipoprotein cholesterol in offspring was studied in relation to total cholesterol levels in their parents in the Epidemiological Prevention Study of Zoetermeer (EPOZ). All residents of 5 or more years who were living in two districts in the Dutch town of Zoetermeer were invited to participate in a study on indicators for chronic diseases between 1975 and 1978. In a random sample of 483 youngsters who were 5-19 years old, yearly measurements of cardiovascular risk factors were performed during a follow-up period of 18 years (average follow-up, 13.8 years). Total and subfraction cholesterol levels in offspring during follow-up were studied by tertiles of age-adjusted total cholesterol in their parents. Total and low density lipoprotein (LDL) cholesterol levels measured from childhood into young adulthood differed significantly between offspring whose fathers were in the highest total cholesterol tertile compared with those whose fathers were in the lowest tertile, amounting to 0.4 mmol/liter for total cholesterol and 0.5 mmol/liter for LDL cholesterol. Offspring differences by maternal tertiles amounted to 0.5 mmol/liter for total cholesterol and 0.6 mmol/liter for LDL cholesterol. Offspring (n = 53) with both parents in the upper cholesterol tertile had almost 1 mmol/liter higher cholesterol levels compared with offspring (n = 51) with both parents in the lowest tertile, whereas offspring (n = 48) with both parents in the middle tertile had intermediate levels. Differences remained after adjustment for sex, Quetelet index, systolic and diastolic blood pressure, and use of alcohol, cigarettes, and oral contraceptives. Offspring group differences in total and LDL cholesterol were already present in childhood and persisted into young adulthood. There was no clear relation between offspring change in cholesterol levels and parental total cholesterol levels. For high density lipoprotein cholesterol and its subfractions, no relations with parental total cholesterol levels were found. Based on the evidence of a strong positive relation between total cholesterol levels in parents and offspring levels of total and LDL cholesterol measured from childhood into young adulthood, the authors conclude that total and LDL cholesterol levels in offspring may already be characterized from young age and beyond through cholesterol levels in their parents.

Lipoproteins and apolipoproteins in the young and familial risk of coronary atherosclerosis

The aim of this study was to assess the predictive value of lipoproteins and apolipoproteins at a young age for the development of coronary artery disease at middle and older ages. Because children of coronary artery disease patients are at high risk themselves we compared lipoprotein and apolipoprotein levels between the offspring of parents with and without coronary artery disease. We selected a group of male patients (n = 90), who had severe coronary atherosclerosis at angiography, and a reference group of male controls (n = 62), who had no coronary atherosclerosis at angiography. Lipoprotein and apolipoprotein levels were determined in 115 sons and 73 daughters of the patients with severe coronary atherosclerosis. These were compared to levels in 68 sons and 47 daughters of controls. Additionally, lipoprotein and apolipoprotein levels were compared between patients and controls as well as between their spouses. In sons of patients, lower levels of HDL3 cholesterol (-0.07 mmol/1, standard error of the mean (SEM) 0.03, P < 0.05) and apolipoprotein A2 (-5.1 mg/dl (SEM, 1.4), P < 0.0001) were found compared to sons of controls. Similar differences were observed in daughters of such patients without, however, achieving statistical significance. No significant differences between the groups of offspring were found for total cholesterol, LDL cholesterol, HDL and HDL2 cholesterol, triglycerides and apolipoproteins A-I and B. Patients had higher levels of total (group difference 0.6 mmol/1 (SEM, 0.18), P < 0.001) and LDL cholesterol (0.6 mmol/1 (SEM, 0.17), P < 0.001), triglycerides (0.6 mmol/1 (SEM, 0.16), P < 0.001) and apolipoprotein B (21.2 mg/dl (SEM, 5.1), P < 0.001), and lower HDL cholesterol (0.1 mmol/1 (SEM, 0.04), P < 0.05) than controls. Spouses of patients had higher levels of triglycerides (0.23 mmol/1 (SEM, 0.11), P < 0.05). Our findings add to the growing evidence that predictors for atherosclerotic disease can be detected relatively early in life. It is concluded that reduced levels of HDL3 cholesterol and apolipoprotein A2 may be early risk indicators for coronary atherosclerosis later in life.

Postprandial triglyceride response in young adult men and familial risk for coronary atherosclerosis

OBJECTIVE

To determine whether an increased familial risk for coronary artery disease in young adult men is related to changes in postprandial lipoprotein metabolism.

DESIGN

Cross-sectional study.

SETTING

Coronary angiography departments of four central general hospitals in the Netherlands.

PATIENTS

80 sons (mean age, 24.8 years) of men with severe coronary artery disease and 55 sons (mean age, 23.2 years) of controls.

MEASUREMENTS

Postprandial levels of serum triglycerides, retinyl palmitate, and total cholesterol were measured during a 12-hour period after a standardized oral lipid load.

RESULTS

Both groups showed a marked increase in levels of serum triglyceride and retinyl palmitate after lipid loading, reaching a maximum 4 to 6 hours postprandially. No changes in postprandial total cholesterol levels were observed in either group. Sons of men with coronary artery disease had prolonged postprandial hypertriglyceridemia when compared with sons of controls. Significant differences in postprandial triglyceride levels were found at 8 hours (difference, 0.35 mmol/L; 95% CI, 0.07 to 0.62 mmol/L), at 10 hours (difference, 0.21 mmol/L; CI, 0.06 to 0.36 mmol/L), and at 12 hours after lipid loading (difference, 0.13 mmol/L; CI, 0.01 to 0.26 mmol/L). Levels of postprandial retinyl palmitate were also slightly, but not statistically, different (mainly after 6 hours).

CONCLUSIONS

Healthy young adult sons, whose fathers have established coronary artery disease, have prolonged postprandial hypertriglyceridemia. Changes in postprandial lipoprotein metabolism appear to be associated with familial risk for coronary atherosclerosis.