Dehydration Status Aggravates Early Renal Impairment in Children: A Longitudinal Study

Dehydration is common in children for physiological and behavioral reasons. The objective of this study was to assess changes in hydration status and renal impairment across school weekdays. We conducted a longitudinal study of three repeated measures of urinalysis within one week in November 2019 in a child cohort in Beijing, China. We measured urine specific gravity (USG) to determine the dehydration status, and the concentration of β2-microglobulin (β2-MG) and microalbumin (MA) to assess renal function impairment among 1885 children with a mean age of 7.7 years old. The prevalence of dehydration was 61.9%, which was significantly higher in boys (64.3%). Using chi-square tests and linear mixed-effects regression models, we documented the trends of the renal indicators’ change over time among different hydration statuses. Compared to Mondays, there were apparent increases of β2-MG concentrations on Wednesdays (β = 0.029, p < 0.001) and Fridays (β = 0.035, p < 0.001) in the dehydrated group, but not in the euhydrated group. As for the MA concentrations, only the decrease on Fridays (β = −1.822, p = 0.01) was significant in the euhydrated group. An increased trend of elevated β2-MG concentration was shown in both the euhydrated group (Z = −3.33, p < 0.001) and the dehydrated group (Z = −8.82, p < 0.001). By contrast, there was a decreased trend of elevated MA concentrations in the euhydrated group (Z = 3.59, p < 0.001) but not in the dehydrated group. A new indicator ratio, β2-MG/MA, validated the consistent trends of renal function impairment in children with dehydration. Renal impairment trends worsened as a function of school days during the week and the dehydration status aggravated renal impairment during childhood across school weekdays, especially tubular abnormalities in children.

Young Adults with Higher Salt Intake Have Inferior Hydration Status: A Cross-Sectional Study

The body’s water and sodium balances are tightly regulated and monitored by the brain. Few studies have explored the relationship between water and salt intake, and whether sodium intake with different levels of fluid intake leads to changes in hydration status remains unknown. The aim of the present study was to determine the patterns of water intake and hydration status among young adults with different levels of daily salt intakes. Participants’ total drinking fluids and water from food were determined by a 7-day 24-h fluid intake questionnaire for 7 days (from Day 1 to Day 7) and duplicate portion method (Day 5, Day 6 and Day 7). Urine of 24 h for 3 days (Day 5, Day 6 and Day 7) was collected and tested for the osmolality, the urine-specific gravity (USG), the concentrations of electrolytes, pH, creatinine, uric acid and the urea. The fasting blood samples for 1 day (Day 6) were collected and measured for the osmolality and the concentrations of electrolytes. The salt intakes of the participants were evaluated from the concentrations of Na of 24 h urine of 3 days (Day 5, Day 6 and Day 7). Participants were divided into four groups according to the quartile of salt intake, including the low salt intake (LS1), LS2, high salt intake (HS1) and HS2 groups. In total, 156 participants (including 80 male and 76 female young adults) completed the study. The salt intakes were 7.6, 10.9, 14.7 and 22.4 g among participants in the four groups (LS1, LS2, HS1 and HS2 groups, respectively), which differed significantly in all groups (F = 252.020; all p < 0.05). Compared to the LS1 and LS2 groups, the HS2 group had 310–381, 250–358 and 382–655 mL more amounts of water from the total water intake (TWI), total drinking fluids and water from food (all p < 0.05), respectively. Participants in the HS2 group had 384–403, 129–228 and 81–114 mL more in the water, water from dishes and staple foods, respectively, than those in the groups of LS1 and LS2 (p < 0.05). The HS2 group excreted 386–793 mL more urine than those in the groups of LS1 and LS2 (p < 0.05). However, regarding urine osmolality, the percentage of participants with optimal hydration status decreased from 41.0% in LS1 and LS2 to 25.6% in the HS2 group (p < 0.05). Participants with higher salt intake had higher TWI, total drinking fluids and water from food. Nevertheless, they had inferior hydration status. A reduction in salt intake should be encouraged among young adults to maintain optimal hydration status.

Acute Kidney Injury Biomarkers and Hydration Outcomes at the Boston Marathon

The purpose of our field study was to investigate the effects of running the Boston Marathon on acute kidney injury (AKI) biomarkers. We hypothesized that biomarker values would be elevated immediately post-marathon but would resolve in the 24-h post-marathon. Secondarily, we sought to identify sex differences related to renal stress. Participants were 65 runners who completed the Boston Marathon (46 ± 9 years, 65.4 ± 10.8 kg). Urine samples were collected at three different time points (pre-marathon, post-marathon, and 24-h post-marathon). Blood samples were collected post-marathon and 24-h post-marathon. Urine specific gravity (USG) and AKI biomarkers were evaluated. Pre-marathon USG (1.012 ± 0.007) was significantly less than post-marathon (1.018 ± 0.008) and 24-h post-marathon (1.020 ± 0.009; P &lt; 0.001). Male USG (1.024 ± 0.009) was significantly greater 24-h post-marathon than females (1.017 ± 0.008; P = 0.019). Urinary neutrophil gelatinase-associated lipocalin values were significantly greater over time (P &lt; 0.001), and there was a main effect of sex with female urinary creatinine (UCr) greater than males at all three time points (P = 0.040). Post-marathonUCr (366.24 ± 295.16 mg/dl) was significantly greater than pre-marathon (206.65 ± 145.28.56 mg/dl; p &lt; 0.001) and 24-h post-marathon was significantly lower than other time-points (93.90 ± 125.07 mg/dl; P &lt; 0.001). FemaleUCr values were significantly greater than males 24-h post-marathon (P &lt; 0.001). There was no difference in serum cystatin C (SCys) values post- or 24-h post-marathon (P = 0.178). Serum creatinine (SCr) significantly decreased between post-marathon and 24-h post-marathon, (P &lt; 0.001). We can infer that the characteristics unique to the Boston Marathon may have attributed to prolonged elevations in AKI biomarkers. Sex differences were observed during the Boston Marathon warranting further investigation.

Fluid Restriction Negatively Influences Perceived Morning Alertness and Visuomotor Ability

The purpose of this study was to assess the effect of two fluid intake protocols on alertness and reaction time before and after fluid intake. Healthy college-age males (n = 12) followed two fluid intake protocols on separate occasions: (1) prescribed fluid (PF) and fluid restricted (FR). In PF, participants were instructed to consume 500 mL of fluid the night prior to and the morning of data collection. In FR, participants were instructed to refrain from the consumption of fluid for 12 h. To assess hydration status, urine specific gravity and urine color were measured. Participants perceived level of thirst and alertness were also recorded. Participants then completed visuomotor reaction time tests using the Dynavision LED board, using both a central visuomotor test and a peripheral visuomotor test (PVRT) prior to (1) and following (2) the ingestion of 100 mL of water. Participants displayed significantly improved PVRT in PF state as compared to FR (PF1 = 1.13 ± 0.16, PF2 = 1.04 ± 0.14; FR1 = 1.27 ± 0.27, FR2 = 1.18 ± 0.20; p = 0.038, ηp2 = 0.363). Both CVRT and PVRT improved over time, following the ingestion of 100 mL of fluid. Participants in the PF state were also significantly more alert than participants in the FR state (PF = 4 ± 2, FR = 5 ± 2; p = 0.019, ES = 0.839). Collectively, perceived alertness and PVRT were negatively impacted by FR.

Hubungan Status Gizi dan Status Hidrasi dengan Fungsi Memori Jangka Pendek Anak Usia Sekolah

ENGLISHShort-term memory in school-age children is significant in the learning process and academic ability improvement. Adequate intake of nutrients and body fluids are needed to accelerate brain performance so that children have optimum memory function. A preliminary study on short term memory of students in SD N Gembong 2, Pati Regency showed that some students experienced a decrease in short-term memory. The objective of this study was to analyze the correlation between nutritional status and nutritional status with children's short-term memory. This study used a correlational design and involved 52 students from 4th - 6th grade in elementary school. The measurement of hydration status used urine specific gravity, while short-term memory was measured using a digit span test. Then, the Chi-Square test was applied to analyze the data. This study result showed that more than half of children had normal nutritional status, good hydration status and normal short-term memory. Furthermore, nutritional status and hydration status were associated with children's short-term memory. Parents should provide more attention to their children’s nutritional and fluid needs, by 1) the children are getting used to taking breakfast before going to school and 2) parents provide meals and drinks from home for their children. INDONESIAMemori jangka pendek pada anak usia sekolah sangat berpengaruh terhadap proses belajar dan upaya peningkatan kemampuan akademik. Asupan nutrisi dan cairan tubuh yang cukup dibutuhkan untuk meningkatkan kerja otak sehingga fungsi memori anak lebih optimal. Data awal penelitian terkait memori jangka pendek anak di SD N Gembong 2 Pati menunjukkan sebagian anak mengalami penurunan memori jangka pendek. Tujuan penelitian ini adalah menganalisis hubungan status gizi dan status nutrisi dengan memori jangka pendek anak. Metode penelitian korelasional dengan jumlah sampel 52 responden anak kelas 4-6 SD. Pengumpulan data status gizi melalui pengukuran berat badan dan tinggi badan. Pengukuran status hidrasi menggunakan pemeriksaan berat jenis urine dan memori jangka pendek menggunakan test digit span. Analisa menggunakan chi square. Hasil penelitian menunjukkan sebagian besar anak mempunyai status gizi normal, status hidrasi baik dan memori jangka pendek yang normal. Terdapat hubungan antara status gizi dan status hidrasi dengan memori jangka pendek anak. Orang tua sebaiknya lebih memperhatikan kebutuhan nutrisi dan cairan anak dengan cara: 1) membiasakan sarapan sebelum berangkat sekolah; dan 2) pada saat anak ke sekolah lebih baik dibawakan bekal makanan dan minuman.

Association of Electrolyte Changes and Inflammatory Markers with Renal Involvement in Children with Febrile UTI

Background: We need some simpler, cheaper, and less burdensome tools to investigate the severity of renal parenchymal involvement in children with clinical pyelonephritis. Objectives: The present study was designed to investigate the relationship between electrolyte changes with renal involvement as documented by dimercaptosuccinic acid (DMSA) scan in children with febrile urinary tract infection (UTI). Methods: This is a retrospective cohort study, involving 158 children aged two months to 14 years with febrile UTI admitted to Taleghani Hospital in Gorgan from 2018 to 2019. Their documents in hospital were analyzed. They were divided into two groups with positive or negative defects on DMSA scan. Clinical and laboratory data were studied. Statistical analysis was performed using SPSS version 18. Data were analyzed using independent t-test with normal distribution of variables, otherwise chi-square test was used. The statistical significance level of the study was considered 0.05. Results: Among the 158 children, 78 patients (49.4%) had normal DMSA scan results, and 80 patients (50.6%) had an abnormal result. The mean age in month was not different between the two groups. In patients with positive renal cortical defects on DMSA Scintigraphy (group 2), ESR was significantly higher than the first group (P < 0.05). The mean serum Na level in the second group was lower than in the first group; however, it was only slightly significant (P = 0.058). The two groups showed no difference with respect to serum potassium, urine specific gravity (SG), WBC count, and the duration of fever (P > 0.05). The frequency distribution of proteinuria was not different between the two groups (P = 0.836). Conclusions: We suggest that increased ESR, positive CRP, and the presence of reflux can predict renal parenchymal involvement in children with febrile UTI as evidenced by a positive finding on DMSA scan, and the presence of hyponatremia has a little predictive value in this regard.

Effect of heat exposure on dehydration and kidney function among sea salt workers in Thailand

Background. Excessive heat exposure and dehydration among agricultural workers have been reported to reduce kidney function and lead to chronic kidney disease of unknown etiology (CKDu). Objective. This cross-sectional study aimed to assess heat exposure, factors related to dehydration and the relationship between dehydration and biomarkers of kidney function among sea salt workers in Thailand. Material and methods. Wet bulb globe temperature (WBGT) was used at the time workers started work outdoors on salt farms. Urine-specific gravity, urine osmolarity, and serum creatinine were collected from 50 workers after work. Results. The results showed that more than 50% of the participants were dehydrated after work. The maximum hours spent working per day was 10. The average water intake was 1.51 L. Urine specific gravity was highly significant correlated with urine osmolality (rs = 0.400, p<0.01), and urine osmolality was significantly correlated with the estimated glomerular filtration rate (eGFR) (rs = 0.349, p<0.05). In bivariate analysis adjusted for age, sex, and current alcohol consumption, we found that a WBGTTWA ≥ 30°C (OR = 0.08, 95% CI = 0.01-0.44, p = 0.003) and hours spent working (OR=2.22, 95% CI = 1.42-3.47, p <0.001) were independently associated with dehydration. This suggests that workers should increase their time spent on breaks and increase water consumption. Conclusions. Educational program on heat exposure and heat-related illness prevention strategies should be provided

Is the Urine Analysis, a Diagnostic Value in COVID-19 Patients?

Background: Severe acute respiratory syndrome coronavirus 2 (SARS CoV-2), a novel coronavirus causing Coronavirus disease 19 (COVID-19) in December 2019, is now a pandemic infectious disease, primarily affecting the respiratory tract. To date, many investigations are available for the diagnosis of SARS-CoV-2. A viral nucleic acid test has been used for the diagnosis of COVID-19, and some hematological indicators have been used in the auxiliary diagnosis and identification of the severity of COVID-19. There are very few studies available in routine urine biochemical parameters and their relation with Covid-19 patients. Aim: This study is aimed to study the changes in urine parameter values in COVID-19 disease and to predict the severity of the disease with the changes in urine parameters. Materials and Methods: A total of 150 patients with COVID-19 were admitted at Saveetha Medical College and Hospital during the study period. All cases tested positive for SARS-CoV-2 by RT-PCR test done on nasopharyngeal swabs during the study period were included. Patients who tested negative by RT-PCR test were considered as controls. The relationship between the results of urine biochemical parameters and the severity of COVID-19 were analysed by Descriptive statistics, Chi-squared test. Results: The positive rates of proteinuria (PRO) and leucocytes were more significant in COVID-19 patients than in healthy controls. The urine specific gravity (SG) value was highly significant (p <0.001) while the blood, nitrites in urine, and potential of hydrogen (pH) value was insignificant. Conclusion: There were some considerable changes in few urine biochemical parameters between patients with the SARS-CoV-2 and healthy controls. So from this study we conclude, proteinuria is helpful for predicting COVID-19 severity and kidney function.