Incidence, Risk Factors, and Outcomes Associated With Recurrent Neonatal Acute Kidney Injury in the AWAKEN Study

Importance

The incidence and associated outcomes of recurrent acute kidney injury (rAKI) in neonates remain largely unknown.

Objective

To determine the incidence, risk factors, and clinical outcomes associated with rAKI in critically ill neonates.

Design, Setting, and Participants

This cohort study was a secondary analysis of the multicenter, international Assessment of Worldwide Acute Kidney Injury Epidemiology in Neonates retrospective study. Comparisons were made among neonates with no AKI, a single AKI episode (sAKI), and rAKI. All neonates younger than 14 days who were admitted between January 1 and March 31, 2014, to 24 participating level II to IV neonatal intensive care units and received intravenous fluids for at least 48 hours were considered for inclusion. Neonates with congenital heart disease requiring surgery within the first week of life, lethal chromosomal anomalies, death within 48 hours of admission, or severe congenital kidney abnormalities were excluded. Data were analyzed from May 23, 2022, to December 8, 2023.

Exposure

Recurrent AKI using the neonatal Kidney Disease: Improving Global Outcomes criteria. Determination of each rAKI required a complete return to the baseline serum creatinine level that defined the prior AKI episode.

Main Outcomes and Measures

Incidence and risk factors of rAKI and associations of rAKI with length of stay (LOS; ie, birth to hospital discharge) and mortality.

Results

The study cohort (n = 2162) included 1233 male neonates (57.0%). Gestational age distribution was less than 29 weeks for 276 neonates (12.8%), 29 to less than 36 weeks for 958 (44.3%), and 36 weeks or older for 928 (42.9%). Of 605 neonates with AKI, 133 (22.0%) developed rAKI with risk factors including younger gestational age, lower birthweight, and higher stage of initial AKI. Infants with rAKI experienced longer median LOS (no AKI, 17 [IQR, 8-34] days; sAKI, 18 [IQR, 9-45] days; rAKI, 60 [IQR, 25-109] days; P < .001). Time-varying Cox proportional hazards regression models suggest rAKI is independently associated with a lower hazard of discharge (adjusted hazard ratio, 0.7 [95% CI, 0.6-0.9]; P = .01) when compared with sAKI, but mortality did not differ between groups (adjusted hazard ratio, 1.4 [95% CI, 0.6-3.0]; P = .44).

Conclusions and Relevance

In this cohort study, neonatal rAKI was independently associated with longer LOS when compared with sAKI, suggesting that rAKI in neonates may be an important clinical distinction warranting further study and careful monitoring after an initial AKI episode.

Streptococcus pneumoniae meningitis in a child with idiopathic nephrotic syndrome: a case report

BACKGROUND

Children with nephrotic syndrome are at increased risk of infections, including bacterial peritonitis, pneumonia, and cellulitis. However, bacterial meningitis, a potentially life-threatening complication, has not been highlighted as an infectious complication of nephrotic syndrome in recent reviews. We report a very subtle and unusual presentation of bacterial meningitis in a child with nephrotic syndrome, which without a high index of suspicion, would have been missed.

CASE PRESENTATION

A 9-year-old African-American male with a history of steroid-dependent nephrotic syndrome presented to the nephrology clinic for routine follow-up. His medications included mycophenolate mofetil and alternate-day steroids. His only complaint was neck pain and stiffness that the mother attributed to muscle tightness relieved by massage. There was no history of fever, vomiting, headache, photophobia, or altered mental status. On physical examination, he was afebrile (99 °F), but had mild periorbital swelling and edema on lower extremities. He appeared ill and exhibited neck rigidity, and demonstrated reflex knee flexion when the neck was bent. Laboratory evaluation revealed leukocytosis, elevated C-reactive protein, hypoalbuminemia, and proteinuria. Cerebrospinal fluid suggested bacterial meningitis. The patient was treated with ceftriaxone and vancomycin. Both cerebrospinal and blood cultures grew Streptococcus pneumoniae; vancomycin was discontinued. The child completed a 2-week course of ceftriaxone and was discharged home.

CONCLUSIONS

A high index of suspicion is necessary in children with nephrotic syndrome treated with corticosteroids, as symptoms may be masked, and thus, a life-threatening disease be missed. Bacterial meningitis should be highlighted as a serious infection complication in children with nephrotic syndrome.

Low albumin levels are independently associated with neonatal acute kidney injury: a report from AWAKEN Study Group

BACKGROUND

Data from adult and pediatric literature have shown an association between albumin levels and AKI. Whether hypoalbuminemia and neonatal AKI are associated has not been studied.

METHODS

We evaluated the association of albumin with early (during the first postnatal week) and late (after the first postnatal week) AKI for 531 neonates from the Assessment of Worldwide AKI Epidemiology in Neonates (AWAKEN) database and for 3 gestational age (GA) subgroups: < 29, 29 to < 36, and ≥ 36 weeks GA.

RESULTS

Low albumin levels were associated with increased odds of neonatal AKI; for every 0.1 g/dL decrease in albumin, the odds of late AKI increased by 12% on continuous analysis. After adjustment for potential confounders, neonates with albumin values in the lowest quartiles (< 2.2 g/dL) had an increased odds of early [Adjusted Odd Ratio (AdjOR) 2.5, 95% CI = 1.1-5.3, p < 0.03] and late AKI [AdjOR 13.4, 95% CI = 3.6-49.9, p < 0.0001] compared to those with albumin in the highest quartile (> 3.1 g/dL). This held true for albumin levels 2.3 to 2.6 g/dL for early [AdjOR 2.5, 95% CI = 1.2-5.5, p < 0.02] and late AKI [AdjOR 6.4, 95% CI = 1.9-21.6, p < 0.01]. Albumin quartiles of (2.7 to 3.0 g/dL) were associated with increased odds of late AKI. Albumin levels of 2.6 g/dL and 2.4 g/dL best predicted early (AUC = 0.59) and late AKI (AUC = 0.64), respectively. Analysis of albumin association with AKI by GA is described.

CONCLUSIONS

Low albumin levels are independently associated with early and late neonatal AKI. Albumin could be a potential modifiable risk factor for neonatal AKI.

Documentation of acute kidney injury at discharge from the neonatal intensive care unit and role of nephrology consultation

OBJECTIVE

To investigate whether NICU discharge summaries documented neonatal AKI and estimate if nephrology consultation mediated this association.

STUDY DESIGN

Secondary analysis of AWAKEN multicenter retrospective cohort.

EXPOSURES

AKI severity and diagnostic criteria.

OUTCOME

AKI documentation on NICU discharge summaries using multivariable logistic regression to estimate associations and test for causal mediation.

RESULTS

Among 605 neonates with AKI, 13% had documented AKI. Those with documented AKI were more likely to have severe AKI (70.5% vs. 51%, p < 0.001) and SCr-only AKI (76.9% vs. 50.1%, p = 0.04). Nephrology consultation mediated 78.0% (95% CL 46.5-109.4%) of the total effect of AKI severity and 82.8% (95% CL 70.3-95.3%) of the total effect of AKI diagnostic criteria on documentation.

CONCLUSION

We report a low prevalence of AKI documentation at NICU discharge. AKI severity and SCr-only AKI increased odds of AKI documentation. Nephrology consultation mediated the associations of AKI severity and diagnostic criteria with documentation.

Hypertension and childhood stroke

Cerebrovascular disease (stroke) is one of the ten leading causes of death in children and adolescents. Multiple etiologies, from arteriopathies to prothrombic states, can cause stroke in youth. In adult stroke, hypertension has been shown to be the single most important modifiable risk factor. Although hypertension has not been strongly identified as a risk factor in childhood stroke to date, there is preliminary evidence that suggests that hypertension may also be associated with stroke in children. In this review, we summarize the literature that may link hypertension to stroke in the young. We have identified a series of barriers and limitations in the fields of pediatric hypertension and pediatric neurology that might explain why hypertension has been overlooked in childhood stroke. We suggest that hypertension may be a relevant risk factor that, alone or in combination with other multiple factors, contributes to the development of stroke in children. Currently, there are no consensus guidelines for the management of post-stroke hypertension in children. Thus, we recommend that blood pressure be assessed carefully in every child presenting with acute stroke in order to better understand the effects of hypertension in the development and the outcome of childhood stroke. We suggest a treatment algorithm to help practitioners manage hypertension after a stroke.

Increased history of ischemic stroke and decreased neurocognitive performance in children with chronic kidney disease

BACKGROUND

This study aimed to determine stroke incidence and assess the association between stroke and neurocognitive functioning in children with chronic kidney disease (CKD).

METHODS

Data was derived from the Chronic Kidney Disease in Children (CKiD) cohort study. Stroke incidence was calculated after confirming self-reports of stroke occurrence by chart review. Each participant with stroke was matched with three stroke-free participants and performance on selected neurocognitive measures was compared. Wilcoxon rank-sum tests were used to compare neurocognitive test scores. Effect size (ES) was estimated using a modified version of Cohen's U₃ metric that measures the excess percentage of the stroke group worse than the median of the control group.

RESULTS

Of 891 subjects, five (0.56%) had a confirmed stroke prior to study entry. Median time at risk was 15.7 years [interquartile range, 12.5-18.4]. Estimated incidence rate of history of stroke was 36.8 per 100,000 children per year (95% confidence interval 15.3, 88.5). Controls and subjects with stroke were similar in age, CKD duration, race, and maternal education. ES for many of the neurocognitive comparisons was moderate to large. Subjects in the CKID cohort with a history of stroke had lower scores on spatial span reverse, spatial span forward, and design fluency, and worse parent ratings on BRIEF Metacognition Index compared to a matched sample of children with CKD without stroke.

CONCLUSIONS

Children with CKD have an increased incidence of prior ischemic stroke compared to the general pediatric population. A stroke history was associated with poorer performance on neurocognitive measures. Graphical abstract.

Change in Dyslipidemia with Declining Glomerular Filtration Rate and Increasing Proteinuria in Children with CKD

BACKGROUND AND OBJECTIVES

Dyslipidemia, a risk factor for cardiovascular disease, is common in CKD but its change over time and how that change is influenced by concurrent progression of CKD have not been previously described.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In the CKD in Children study we prospectively followed children with progressive CKD and utilized multivariable, linear mixed-effects models to quantify the longitudinal relationship between within-subject changes in lipid measures (HDL cholesterol, non-HDL cholesterol, triglycerides) and within-subject changes in GFR, proteinuria, and body mass index (BMI).

RESULTS

A total of 508 children (76% nonglomerular CKD, 24% glomerular CKD) had 2-6 lipid measurements each, with a median follow-up time of 4 (interquartile range [IQR], 2.1-6.0) years. Among children with nonglomerular CKD, dyslipidemia was common at baseline (35%) and increased significantly as children aged; 43% of children with glomerular CKD had dyslipidemia at baseline and demonstrated persistent levels as they aged. Longitudinal increases in proteinuria were independently associated with significant concomitant increases in non-HDL cholesterol (nonglomerular: 4.9 [IQR, 3.4-6.4] mg/dl; glomerular: 8.5 [IQR, 6.0-11.1] mg/dl) and triglycerides (nonglomerular: 3% [IQR, 0.8%-6%]; glomerular: 5% [IQR, 0.6%-9%]). Decreases in GFR over follow-up were significantly associated with concomitant decreases of HDL cholesterol in children with nonglomerular CKD (-1.2 mg/dl; IQR, -2.1 to -0.4 mg/dl) and increases of non-HDL cholesterol in children with glomerular CKD (3.9 mg/dl; IQR, 1.4-6.5 mg/dl). The effects of increased BMI also affected multiple lipid changes over time. Collectively, glomerular CKD displayed stronger, deleterious associations between within-subject change in non-HDL cholesterol (9 mg/dl versus 1.2 mg/dl; P<0.001) and triglycerides (14% versus 3%; P=0.004), and within-subject change in BMI; similar but quantitatively smaller differences between the two types of CKD were noted for associations of within-subject change in lipids to within-subject change in GFR and proteinuria.

CONCLUSIONS

Dyslipidemia is a common and persistent complication in children with CKD and it worsens in proportion to declining GFR, worsening proteinuria, and increasing BMI.

Neurological complications in childhood nephrotic syndrome: A systematic review

BACKGROUND AND OBJECTIVE

Nephrotic syndrome (NS) in childhood can be accompanied by serious neurological complications increasing the morbidity of disease. The study aimed to assess the spectrum of neurological complications in children with in terms of clinical presentation, contributory risk factors, and outcome.

METHODS

In this systematic review, we searched for articles in PubMed, providing individual patient-level data for any neurological complication in children and adolescents with primary NS, between January 1, 1990 and April 30, 2018.

FINDINGS

The search yielded 63 articles, involving 103 patients. Events occurred more frequently during nephrotic state relapses; 71.6% of cerebral thromboembolic (TE) events and 81.2% of posterior reversible encephalopathy (PRES) cases. Median duration of disease before a cerebral TE event was 3 months (IQR 0-27), and 18 months (IQR 1-37.5) for PRES. Among cases with TE, 73.1% presented with cerebral sinovenous thrombosis (CSVT), and 16.9% parenchymal lesions. 70% of patients had a risk factor for neurological complication including NS-associated thrombophilia, hypertension, and treatment with immunosuppressive agents. Outcome was favorable in 93.8% of the patients with PRES. In patients with cerebral TE outcome was favorable in 95.8% of the cases with CSVT only, and in 64.7% of the cases with parenchymal lesions.

CONCLUSIONS

Neurological complications may occur in children with primary NS and risk factors during nephrotic state relapses. The outcome for PRES has been reported favorable. Outcome in cerebral TE events may differ by the presence of venous or artery infarct. Recognition of additional protrombotic state risk factors may help to lower the incidence of neurological complications.

Ambulatory blood pressure monitoring and neurocognitive function in children with primary hypertension

BACKGROUND

Children with primary hypertension have been reported to have diminished scores in measures of cognition. However, little is known about the relative correlation between office and ambulatory blood pressure (BP) and neurocognitive test performance, and whether short-term BP variability is associated with decreased neurocognitive function. We sought to determine whether ambulatory BP monitoring (ABPM) was more strongly associated with neurocognitive test performance compared with office BP, and whether increased short-term BP variability was associated with lower neurocognitive scores.

METHODS

Seventy-five subjects ages 10-18 years, with untreated primary hypertension, and 75 matched normotensive controls completed neurocognitive testing. All subjects had office BP and ABPM prior to neurocognitive testing.

RESULTS

On multivariate analyses, there was no significant association between office BP and neurocognitive tests. However, several ABPM parameters were significantly associated with neurocognitive test scores in the lower quartile, in particular 24 h SBP load and wake systolic blood pressure (SBP) index [Rey Auditory Verbal learning Test (RAVLT) List A Trial 1, 24 h SBP load, odds ratio (OR) = 1.02, wake SBP index, OR = 1.06; List A Total, 24 h SBP load, OR = 1.02, wake SBP index, OR = 1.06; Short Delay Recall, wake SBP index, OR = 1.06; CogState Maze delayed recall, 24 h SBP load, OR = 1.03, wake SBP index, OR = 1.08; Grooved Pegboard, 24 h SBP load, OR = 1.02; all p < 0.05]. In contrast, short-term BP variability measures were not associated with neurocognitive test performance.

CONCLUSIONS

ABPM is superior to office BP in distinguishing hypertensive youth with lower neurocognitive test performance.

Neurocognitive Function in Children with Primary Hypertension after Initiation of Antihypertensive Therapy

OBJECTIVE

To determine the change in neurocognitive test performance in children with primary hypertension after initiation of antihypertensive therapy.

STUDY DESIGN

Subjects with hypertension and normotensive control subjects had neurocognitive testing at baseline and again after 1 year, during which time the subjects with hypertension received antihypertensive therapy. Subjects completed tests of general intelligence, attention, memory, executive function, and processing speed, and parents completed rating scales of executive function.

RESULTS

Fifty-five subjects with hypertension and 66 normotensive control subjects underwent both baseline and 1-year assessments. Overall, the blood pressure (BP) of subjects with hypertension improved (24-hour systolic BP load: mean baseline vs 1 year, 58% vs 38%, P < .001). Primary multivariable analyses showed that the hypertension group improved in scores of subtests of the Rey Auditory Verbal Learning Test, Grooved Pegboard, and Delis-Kaplan Executive Function System Tower Test (P < .05). However, the control group also improved in the same measures with similar effects sizes. Secondary analyses by effectiveness of antihypertensive therapy showed that subjects with persistent ambulatory hypertension at 1 year (n = 17) did not improve in subtests of Rey Auditory Verbal Learning Test and had limited improvement in Grooved Pegboard.

CONCLUSIONS

Overall, children with hypertension did not improve in neurocognitive test performance after 1 year of antihypertensive therapy, beyond that also seen in normotensive controls, suggesting improvements with age or practice effects because of repeated neurocognitive testing. However, the degree to which antihypertensive therapy improves BP may affect its impact upon neurocognitive function.

Stroke and Hypertension in Children and Adolescents

Hypertension is the single most important modifiable risk factor for adult stroke. Stroke mortality has significantly decreased over the last 5 decades; this decline has been mainly associated to improved blood pressure control. Though much less prevalent than in adults, stroke is an increasingly recognized cause of morbidity and mortality in children. Although hypertension has not been strongly identified as a risk factor in childhood stroke yet, there is preliminary evidence that suggests that elevated blood pressure may be associated with stroke in children. This review summarizes the literature that may link elevated blood pressure to the development of childhood ischemic and hemorrhagic stroke. The authors suggest that elevated blood pressure may be a significant risk factor that, alone or in combination with other multiple risk factors, leads to the development of stroke in childhood. It is therefore recommend that blood pressure be measured and assessed carefully in every child presenting with acute stroke.

Neurocognitive Function in Children with Primary Hypertension

OBJECTIVE

To compare neurocognitive test performance of children with primary hypertension with that of normotensive controls.

STUDY DESIGN

Seventy-five children (10-18 years of age) with newly diagnosed, untreated hypertension and 75 frequency-matched normotensive controls had baseline neurocognitive testing as part of a prospective multicenter study of cognition in primary hypertension. Subjects completed tests of general intelligence, attention, memory, executive function, and processing speed. Parents completed rating scales of executive function and the Sleep-Related Breathing Disorder scale of the Pediatric Sleep Questionnaire (PSQ-SRBD).

RESULTS

Hypertension and control groups did not differ significantly in age, sex, maternal education, income, race, ethnicity, obesity, anxiety, depression, cholesterol, glucose, insulin, and C-reactive protein. Subjects with hypertension had greater PSQ-SRBD scores (P = .04) and triglycerides (P = .037). Multivariate analyses showed that hypertension was independently associated with worse performance on the Rey Auditory Verbal Learning Test (List A Trial 1, P = .034; List A Total, P = .009; Short delay recall, P = .013), CogState Groton Maze Learning Test delayed recall (P = .002), Grooved Pegboard dominant hand (P = .045), and Wechsler Abbreviated Scales of Intelligence Vocabulary (P = .016). Results indicated a significant interaction between disordered sleep (PSQ-SRBD score) and hypertension on ratings of executive function (P = .04), such that hypertension heightened the association between increased disordered sleep and worse executive function.

CONCLUSIONS

Youth with primary hypertension demonstrated significantly lower performance on neurocognitive testing compared with normotensive controls, in particular, on measures of memory, attention, and executive functions.

Constipation, renovascular hypertension, and posterior reversible encephalopathy syndrome (PRES)

Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological entity characterized by variable associations of headaches, encephalopathy, seizures, vomiting, visual disturbance, and focal neurological signs. Neuroimaging shows cerebral edema of different patterns, classically involving the parieto-occipital white matter. PRES has been associated with several conditions predominantly hypertension, eclampsia, and immunosuppressive therapy. However, constipation has not been previously described in association with the development of PRES. In this report, we describe an 11-year-old child with history of severe functional constipation who developed PRES, as a consequence of renovascular hypertension from severe fecal impaction. Both hypertension and neurologic dysfunction resolved after resolution of fecal impaction.

CONCLUSION

Severe functional constipation is a previously unrecognized cause of severe acute hypertension, resulting in life-threatening neurologic dysfunction. We highlight this unrecognized complication of severe functional constipation with fecal impaction that is potentially preventable if managed appropriately.

Sleep disordered breathing as measured by SRBD-PSQ and neurocognition in children with hypertension

BACKGROUND

Cognitive test performance is decreased in hypertensive adults and children, a finding postulated to represent early target-organ damage to the brain. Hypertensive children are often obese, a comorbidity associated with sleep disordered breathing (SDB), itself associated with cognitive problems; potentially confounding the relation between hypertension (HTN) and neurocognition. Our objective was to determine the association between SDB as measured by a scale and questionnaire score and neurocognition among participants enrolled in an ongoing multicenter study of cognition in children with HTN.

METHODS

Subjects completed laboratory-based neurocognitive tests. Parents and subjects completed rating scales of executive function, mood, and behavior problems. Parents completed the Sleep-Related Breathing Disorder scale of the Pediatric Sleep Questionnaire (SRBD-PSQ).

RESULTS

To date, 38 HTN subjects and 34 control subjects have completed neurocognitive testing and the SRBD-PSQ. Median SRBD-PSQ scores were similar between groups but the HTN group had a higher percentage of subjects with SRBD-PSQ scores in the range suggestive of obstructive sleep apnea (26% vs. 6%, P = 0.03). Overall, higher SRBD-PSQ scores were not significantly associated with worse performance on laboratory-based measures of executive function and other cognitive domains but were significantly associated with worse scores on rating scales of executive function as well as mood and behavior problems.

CONCLUSIONS

A larger proportion of children with HTN had scores suggestive of SDB. The results underscore the importance of using a multi-method approach in the assessment of cognition and adjusting for potential confounding effects of SDB in studies of cognition in hypertensive children.

Executive function and cerebrovascular reactivity in pediatric hypertension

Primary hypertension is associated with decreased performance on neurocognitive testing and a blunted cerebrovascular reactivity to hypercapnia. Parents of 14 children with hypertension and prehypertension completed the Behavior Rating Inventory of Executive Functions. Children underwent 24-hour ambulatory blood pressure monitoring and transcranial Doppler with reactivity measurement using time-averaged maximum mean velocity and end-tidal carbon dioxide during hypercapnia-rebreathing test. Comparing the reactivity slope for the patients to historical controls showed a statistically significant difference (t = -5.19, df = 13, P < .001), with lower slopes. Pearson correlations of the Behavior Rating Inventory of Executive Functions scores with the reactivity slopes showed a statistically significant inverse relationship with Behavioral Regulation Index (r = -.60, P = .02), Metacognition Index (r = -.40, P = .05), and the Global Executive Component (r = -.53, P = .05). Children with hypertension have decreased executive function, and this correlates to low transcranial Doppler-reactivity slopes, suggesting that the brain is a target organ in hypertensive children.

Cognitive function in hypertensive children

Young hypertensive adults demonstrate decreased performance on neurocognitive testing compared with that of normotensive controls. There is emerging, preliminary evidence that children with hypertension also manifest cognitive differences when compared to normotensive controls. These preliminary studies consist mostly of database and single-center studies that focus primarily on differences in neurocognitive test performance and differences in cerebrovascular reactivity between hypertensive and normotensive subjects. Lessons from the literature on cognition in adult hypertensives and experience from the preliminary studies in children informed the design of a current, multicenter, ongoing study of cognition in children with primary hypertension.

BP control and left ventricular hypertrophy regression in children with CKD

In adult patients with CKD, hypertension is linked to the development of left ventricular hypertrophy, but whether this association exists in children with CKD has not been determined conclusively. To assess the relationship between BP and left ventricular hypertrophy, we prospectively analyzed data from the Chronic Kidney Disease in Children cohort. In total, 478 subjects were enrolled, and 435, 321, and 142 subjects remained enrolled at years 1, 3, and 5, respectively. Echocardiograms were obtained 1 year after study entry and then every 2 years; BP was measured annually. A linear mixed model was used to assess the effect of BP on left ventricular mass index, which was measured at three different visits, and a mixed logistic model was used to assess left ventricular hypertrophy. These models were part of a joint longitudinal and survival model to adjust for informative dropout. Predictors of left ventricular mass index included systolic BP, anemia, and use of antihypertensive medications other than angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. Predictors of left ventricular hypertrophy included systolic BP, female sex, anemia, and use of other antihypertensive medications. Over 4 years, the adjusted prevalence of left ventricular hypertrophy decreased from 15.3% to 12.6% in a systolic BP model and from 15.1% to 12.6% in a diastolic BP model. These results indicate that a decline in BP may predict a decline in left ventricular hypertrophy in children with CKD and suggest additional factors that warrant additional investigation as predictors of left ventricular hypertrophy in these patients.

A multicenter study of neurocognition in children with hypertension: methods, challenges, and solutions

Hypertensive adults demonstrate decreased performance on neurocognitive testing compared with that of normotensive controls. There is now emerging, preliminary evidence that children with hypertension also manifest neurocognitive differences when compared with normotensive controls, findings postulated to potentially represent early signs of hypertensive target organ damage to the brain. However, reports in children to date have been limited to database and single-center studies. We have established an ongoing, prospective, multicenter study of neurocognition in children with primary hypertension. This article outlines the study methods, with particular attention to the unique challenges in this area of clinical research. We highlight aspects of the study design that are specifically designed as solutions to these challenges.

Primary hypertension and neurocognitive and executive functioning in school-age children

Data on neurocognitive function in hypertensive children are limited. In this review, we summarize recent preliminary, early studies that suggest that children with elevated blood pressure demonstrate evidence of worse performance on direct neurocognitive testing, as well as evidence of executive dysfunction based on parent ratings, compared with matched normotensive comparison groups. Furthermore, hypertensive children may have increased prevalence of learning disabilities as well as a blunted cerebrovascular reactivity compared with normotensive controls. Larger, prospective studies are needed to confirm and further explore these emerging but preliminary findings.

Neurocognitive alterations in hypertensive children and adolescents

Hypertensive adults demonstrate performance deficits on neuropsychological testing compared with scores of normotensive controls. This article reviews emerging preliminary evidence that children with hypertension also manifest neurocognitive differences when compared with normotensive controls. Database and single-center studies suggest that children with hypertension manifest deficits on measures of neurocognition and have an increased prevalence of learning difficulties and that children with hypertension associated with obesity may be at increased risk for depression and anxiety. Studies suggesting blunted cerebrovascular reactivity in children with hypertension are also reviewed.

Brain hypoperfusion in a girl with systemic lupus erythematosus

We describe an adolescent girl with systemic lupus erythematosus, presenting with severe cardiovascular autonomic dysfunction and incapacitating orthostatic hypotension to a degree not previously reported. Further evaluation of cerebral blood flow velocity, using transcranial Doppler testing, demonstrated an abnormal hypercapnic cerebrovascular response. Both the orthostatic hypotension and the abnormal cerebrovascular hypercapnic response improved with intensive medical treatment of her systemic lupus erythematosus. Additional studies are necessary to elucidate the pathogenesis of these cerebrovascular and autonomic abnormalities, especially considering the potential consequences they may exert on cerebral perfusion, which may be subtle, underrecognized, and capable of affecting cognition.

Unmasking of neonatal renovascular hypertension by milrinone used for cardiac dysfunction

A neonate initially presented with heart failure, with severe cardiac dysfunction confirmed by echocardiography, at 3 days of age. Blood pressure at presentation was in the high normal range. It was not until there was a rapid improvement of left-ventricular function on intravenous milrinone that the infant was noted to be hypertensive on day of life 7. It is noteworthy that milrinone, a drug with vasodilator and inotropic properties, paradoxically unmasked hypertension by rapidly improving left-ventricular function. Subsequent work-up showed the etiology of hypertension to be left renal artery stenosis. We present this case to alert clinicians to the rarer causes of left-ventricular dysfunction and to point out that its etiology, i.e., hypertension, may not be apparent until there is improvement in the systolic function of the left ventricle.

Hypertension impairs vascular reactivity in the pediatric brain

BACKGROUND AND PURPOSE

Chronic hypertension impairs cerebrovascular regulation in adults, but its effects on the pediatric population are unknown. The objective of this study was to investigate cerebrovascular abnormalities in hypertensive children and adolescents.

METHODS

Sixty-four children and adolescents aged 7 to 20 years underwent transcranial Doppler examinations of the middle cerebral artery at the time of rebreathing CO2. Time-averaged maximum mean cerebral blood flow velocity and end-tidal CO2 were used to quantify cerebrovascular reactivity during hypercapnia. Patients were clinically categorized as hypertensive, prehypertensive, or white coat hypertensive based on 24-hour ambulatory blood pressure measurements. Their reactivities were compared with 9 normotensive control subjects and evaluated against baseline mean blood pressure z-scores and loads.

RESULTS

Untreated hypertensive children had significantly lower hypercapnic reactivity than normotensive children (2.556 +/- 1.832 cm/s x mm Hg versus 4.256 +/- 1.334 cm/s x mm Hg, P < 0.05). Baseline mean diastolic blood pressure z-scores (r = -0.331, P = 0.037) and diastolic blood pressure loads (r = -0.351, P = 0.026) were inversely related to reactivity.

CONCLUSIONS

Untreated hypertensive children and adolescents have blunted reactivity to hypercapnia, indicating deranged vasodilatory reactivity. The inverse relationship between diastolic blood pressure indices and reactivity suggests that diastolic blood pressure may be a better predictor of cerebral end organ damage than systolic blood pressure.

Dyslipidemia in children with chronic kidney disease

Dyslipidemia, a known risk factor for atherosclerosis, is frequent among both adults and children with chronic kidney disease. Here, we describe the prevalence and pattern of dyslipidemia from a cross-sectional analysis of 391 children aged 1-16 years, enrolled in the multicenter Chronic Kidney Disease in Children (CKiD) study, with a median glomerular filtration rate (GFR), measured by the plasma disappearance of iohexol, of 43 ml/min per 1.73 m2. Multivariate analysis was applied to adjust for age, gender, body mass index (BMI), GFR, and the urinary protein/creatinine ratio. Proteinuria was in the nephrotic range in 44 and the BMI exceeded the 95th percentile in 57 patients of this cohort. Baseline lipid analysis found a high prevalence of hypertriglyceridemia in 126, increased non-HDL-C in 62, and reduced HDL-C in 83. Overall, 177 children had dyslipidemia, of whom 79 had combined dyslipidemia. Lower GFR was associated with higher triglycerides, lower HDL-C, and higher non-HDL-C. Nephrotic-range proteinuria was significantly associated with dyslipidemia and combined dyslipidemia. Compared with children with a GFR>50, children with a GFR<30 had significantly increased odds ratios for any dyslipidemia or for combined dyslipidemia. Hence, among children with moderate chronic kidney disease, dyslipidemia is common and is associated with lower GFR, nephrotic proteinuria, and non-renal factors including age and obesity.

Increased prevalence of renal and urinary tract anomalies in children with Down syndrome

OBJECTIVE

The goal was to investigate the prevalence of renal and urinary tract anomalies (RUTAs) in a Down syndrome (DS) population.

METHODS

Data were obtained from the New York State Congenital Malformation Registry (NYS-CMR) in this retrospective cohort study. The occurrence of RUTAs was assessed for children with and without DS who were born in NYS between 1992 and 2004. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for each malformation.

RESULTS

Between 1992 and 2004, 3832 children with DS and 3 411 833 without DS were born in NYS. The prevalence of RUTAs in the DS population was 3.2%, compared with 0.7% in the NYS population (OR: 4.5 [95% CI: 3.8 -5.4]). Children with DS had significantly increased risks of anterior urethral obstruction (OR: 29.7 [95% CI: 4.0 -217.7]), cystic dysplastic kidney (OR: 4.5 [95% CI: 1.5-14.1]), hydronephrosis (OR: 8.7 [95% CI: 6.8 -11.0]), hydroureter (OR: 8.5 [95% CI: 3.5-20.4]), hypospadias (OR: 2.0 [95% CI: 1.4 -2.9]), posterior urethral valves (OR: 7.1 [95% CI: 1.8 -28.8]), prune belly syndrome (OR: 11.9 [95% CI: 1.6 - 85.4]), and renal agenesis (OR: 5.4 [95% CI: 2.8 -10.4]). There was no significantly increased risk of ectopic kidney (OR: 1.6 [95% CI: 0.2-11.2]) or ureteropelvic junction obstruction (OR: 1.4 [95% CI: 0.2-9.9]) in the DS population.

CONCLUSION

Children with DS have significantly increased risks of RUTAs.

Electrocardiographic predictors of left ventricular hypertrophy in pediatric hypertension

OBJECTIVE

To determine the efficacy of electrocardiography (ECG) in detecting left ventricular hypertrophy (LVH) in pediatric hypertension (HT).

STUDY DESIGN

Concomitant echocardiograms and electrocardiograms in 108 children with HT were reviewed. Left ventricular mass (LVM), assessed by echocardiography, was used as a basis for a diagnosis of LVH (echo LVH) using accepted pediatric criteria. Using Wilcoxon's rank-sum test, 14 ECG variables were compared between subjects with and without echo LVH. Spearman correlations were used to examine the linear association between echo LVH and these ECG variables. The sensitivity and specificity of ECG in diagnosing LVH were computed.

RESULTS

Of the 108 subjects studied, 35 (32%) met the pediatric criteria for LVH; of these, 8 (7.4%) also met the adult criteria (>51 g/m(2.7)) for LVH. Mean values for only 5 ECG criteria differed significantly among the groups: RI, SaVR, RaVL, RI+SIII, and SVI+RV6 (P < .05). Significant correlations were found for several ECG criteria and at least 1 measure of LVM, but the magnitudes were modest. Standard ECG criteria predicted LVH with high specificity (>90%) but low sensitivity (<35%). RI >10 mm was identified as demonstrating a modestly improved positive likelihood ratio of approximately 3.

CONCLUSIONS

ECG is not an adequate predictor of LVH for clinical use in HT.

Lacunar stroke and masked hypertension in an adolescent male

Hypertension has not been strongly identified as a risk factor in childhood stroke. This report describes a case of a teenager with a lacunar stroke, the type often observed in adults with hypertensive-associated infarction, and masked hypertension. The patient had normal blood pressure on initial presentation, but on further investigation demonstrated ambulatory hypertension with evidence of hypertensive end-organ damage. This case suggests that hypertension may be a risk factor in children with stroke, especially in cases of lacunar infarct. Evaluation for possible hypertension should be undertaken thoroughly to identify children who may benefit from antihypertensive therapy and therefore, prevent recurrences.

Regression of left ventricular hypertrophy in children with antihypertensive therapy

Left ventricular hypertrophy (LVH) is a complication of hypertension that has received great attention in the adult population. Large-scale randomized control studies in adults have demonstrated that LVH regresses in response to pharmacologic intervention. While it is known that LVH occurs as a complication of hypertension in the pediatric population, few studies have focused on its regression with pharmacological intervention. We report on three cases of hypertension-induced LVH in the pediatric population and its regression after treatment with antihypertensive medications. This report brings to light the need for larger, prospective studies on the incidence, natural history, and treatment of LVH associated with hypertension in the pediatric population.

Posterior urethral valves in patients with Down syndrome

Renal and urological anomalies in Down syndrome (DS) have received little attention compared with the nephrourological findings described in other chromosomal abnormalities. Renal hypoplasia, hydroureteronephrosis, ureterovesical and ureteropelvic junction obstruction, and vesicoureteral reflux, but not posterior urethral valves, have been associated with DS. We report the occurrence of posterior urethral valves in three male infants with DS at a single institution. All had multiple urological procedures for correction or palliation of obstruction. Children with DS may have an increased risk for developing posterior urethral valves and obstructive uropathy. Furthermore, they may also develop chronic renal failure secondary to posterior urethral valves. Therefore, we suggests that infants with DS be screened with ultrasonography for renal and urological abnormalities early in life and, if abnormal, a contrast voiding cystourethrogram be performed to rule out posterior urethral valves or other bladder or urethral abnormalities. A review of the renal and urological anomalies in DS reported in the literature since 1960 is presented.

Megacystis-microcolon-intestinal hypoperistalsis syndrome

The megacystis-microcolon-intestinal hypoperistalsis syndrome is a congenital disorder characterized by urinary bladder distension and hypoperistalsis throughout the entire gastrointestinal tract. We present a new case with the typical clinical, radiological, and pathological findings of the syndrome. The diagnosis should be suspected in a patient who present clinically with intestinal obstruction and urinary retention, and confirmed with imaging studies, including abdominal plain films, urinary tract ultrasonography, and contrast studies of the colon and the bladder. The prognosis is generally very poor. Our patient died secondary to sepsis on day 5 of life.