Association between serum albumin and body water using a bioelectrical impedance analyzer: a case report of longitudinal variation in a child with initial idiopathic nephrotic syndrome.

Background: Bioelectrical impedance analysis (BIA) is a commonly used noninvasive technique for body composition assessment with recently expanded indications. This reproducible measurement method uses electrical conductivity to evaluate body composition, including fluid status. In pediatric idiopathic nephrotic syndrome (INS), albumin leaks into the urine, resulting in dysregulated colloid-osmotic pressure in the blood vessels. This results in decreased circulating blood volume and edema. Blood tests are a useful evaluation method; however, it cannot be performed frequently in children because of their invasive nature. Herein, we present a case of a child with INS demonstrating a longitudinal correlation between serum albumin (S-Alb) levels and extracellular water (ECW)/total body water (TBW) ratio. Case Description: A 6-year-old boy was admitted to the hospital for INS treatment after informed consent was obtained. He presented with severe proteinuria symptoms and an increased weight of 3 kg before the onset of INS. Standard treatment with prednisolone (PSL) for 28 days was initiated, and his proteinuria resolved on day 7. During the acute course, albumin replacement was conducted thrice for fluid management purposes and did not cause severe intravascular dehydration. The fluid composition was assessed over time; each measurement lasted for approximately 10 minutes and was performed on the same day as the blood tests. Nine measurements were taken, and S-Alb levels and the ECW/TBW ratio (r=-0.72, P<0.04) exhibited a significant negative correlation. Conclusions: BIA can potentially predict S-Alb levels objectively and noninvasively within a short period. Although further validation is needed, this measurement can reduce the invasiveness of testing in children with INS.

Effect of proteinuria at relapse on shear wave velocity assessed using ultrasound elastography in children with idiopathic nephrotic syndrome.

PURPOSE: Shear wave velocity (SWV) is an ultrasound elastography technique that provides much information for kidney disease assessment. However, the factors that alter SWV are not fully understood; it is unclear whether the variation in SWV seen in proteinuria associated with disease progression is due to tissue or proteinuria. This study investigated the effect of proteinuria on SWV. METHODS: This prospective observational study compared SWV at remission with SWV at relapse in children treated for idiopathic nephrotic syndrome (INS) between April 2020 and December 2023. All relapses without oral steroids during the observation period were measured. SWV at remission was defined as the date closest to relapse during which repeated measurements were taken approximately every 3 months after steroid discontinuation. RESULTS: Eight patients were treated for INS with a median observation period of 21.9 months (11.8-27.1). Of the 15 relapses, five that met the definition were considered for the study. The median interval between the measurement at relapse and remission was 40 days (11-55). SWV was significantly lower at relapse than remission (2.40 ± 0.20 m/s vs. 2.14 ± 0.15 m/s, P < 0.01). CONCLUSIONS: SWV decreased in the presence of severe proteinuria at relapse compared to the remission measurements. Although more cases need to be studied, the decrease in SWV may reflect the mechanism by which protein leaks into the urine, not just a direct change caused by the presence of proteinuria.

A case of rapid avacopan-induced liver injury in pediatric granulomatosis with polyangiitis.

Children with anti-neutrophil cytoplasmic antibody-associated vasculitis benefit immensely from avacopan as it reduces the requirement for steroids. However, descriptions of adverse drug reactions in children are lacking, and the dosage and follow-up intervals are unclear. A 10-year-old boy with initial granulomatosis and polyangiitis presented with diffuse pulmonary hemorrhage. Rituximab and 30 mg avacopan were administered twice daily as induction therapy following methylprednisolone pulse therapy. However, sudden liver function test abnormalities were observed on day 31 of avacopan treatment, despite liver enzyme levels being within the normal range 5 days earlier. A drug-induced lymphocyte stimulation and various infectious disease tests yielded negative results. Discontinuation of rituximab and avacopan resulted in improved liver function; no change in the Birmingham Vasculitis Activity Score during liver function test abnormalities was observed. Avacopan-associated abnormalities in liver function tests suggest that drug-induced liver injury may occur rapidly in children, and appropriate dosing strategies should be reconsidered.

Infants With Dorsal Hand Compartment Syndrome Due to Intravenous Infiltration of Glucose Acetate Ringer's Solution.

Compartment syndrome caused by glucose acetate Ringer's solution in children has not been sufficiently reported. We report the cases of two children who developed compartment syndrome of the dorsum of the hand and forearm after receiving only glucose acetate Ringer's solution during hospitalization, with one case requiring a releasing incision. In recent years, glucose acetate Ringer's solution has been frequently used for maintenance infusion. However, it is not always safe and should be used with caution due to the risk of serious side effects caused by infiltration.

Glomeruli Count and Arterial Injury in Real-Time Ultrasound-Guided Needle Kidney Biopsy Specimens: Adequacy of Three Approaches for Pig Kidneys.

INTRODUCTION: Real-time ultrasound-guided percutaneous kidney biopsy is essential for diagnosis and treatment planning; nonetheless, the optimal puncture approach has yet to be established. In vivo, performing different approaches on the same patient at once is not possible. This study aimed to determine the impact of different approaches on the number of obtained glomeruli and their potential to cause arterial injury using pig kidneys, which are similar to humans. METHODS: A total of 120 pig kidneys (60 right-sided kidneys and 60 left-sided kidneys) for research were obtained from a slaughterhouse. The specimens were collected from the lower pole on the sagittal plane of the kidney using three different approaches on the same kidney: caudocranial approach, caudal to cranial; craniocaudal approach, cranial to caudal; and vertical approach, through the surface cortex. Five blinded pediatric nephrologists assessed the number of glomeruli and arterial injuries. RESULTS: Overall, 360 specimens were collected from the kidneys through biopsy using a 16-gauge needle (mean vertical kidney length, 11.2 ± 0.7 cm; mean depth, 3.47 ± 0.23 cm). No significant difference in the incidence of arterial injury was observed between the three approaches (caudocranial vs. craniocaudal vs. vertical approaches: 78% vs. 87% vs. 87%, p = 0.14). In contrast, the vertical approach retrieved significantly more glomeruli than the caudocranial and craniocaudal approaches (caudocranial approach: 7.5 ± 2.8, craniocaudal approach: 7.8 ± 2.7, and vertical approach: 8.9 ± 3.3, p < 0.001). CONCLUSIONS: Considering its efficacy and safety profile, the vertical approach may be preferred, as more glomeruli can be obtained without increasing the incidence of arterial injury. Although the results cannot be directly extrapolated to humans due to the differences between species, they still offer important insights into the characteristics of each approach.

Paraspinal muscle abscesses in children - A case report and review of the literature.

Background: Few pediatric cases with myositis and abscesses of the paraspinal muscles have been previously reported. Case Description: We herein report on a 3-year-old patient who developed an epidural abscess in a paraspinal muscle abscess, after a complication of infectious impetigo due to atopic dermatitis. The child improved through the administration of an antibacterial drug. The median age of seven patients with a history of paraspinal muscle inflammation and muscle abscess was 12 years old (3-15-years-old), few of which had underlying diseases, with methicillin-sensitive Staphylococcus aureus being the main causative agent. Although the prognosis was well in many cases following the administration of antibacterial agents, there were also cases in which extensive lesions were found and neurological sequelae remained. Conclusion: The current case was the youngest case ever reported of a paraspinal muscle abscess. Although pediatric cases are rare, in the episode of a fever of unknown origin and difficulty walking, paraspinal muscle abscesses should be cited as a differential diagnosis and appropriate early diagnostic imaging and treatment should be performed.

A Case of Kikuchi's Disease Without Cervical Lymphadenopathy.

Background: Kikuchi's disease with only extracervical lymphadenopathy is rare. Case Presentation. A 15-year-old male has presented with a fever lasting more than 1 week and right axillary lymphadenopathy. An axillary lymph node biopsy revealed coagulation necrosis, nuclear decay products, infiltration of histiocytes, and enlarged lymphocytes; he was diagnosed with Kikuchi's disease. The only four adult patients with Kikuchi's disease presenting without cervical lesions have been previously reported. Conclusion: This is the only pediatric case of Kikuchi's disease presenting without cervical lymphadenopathy. Kikuchi's disease should be included in the differential diagnosis even in cases of extracervical lymphadenopathy alone.

Effects of diurnal variation of bile acids by meal on cyclosporine A absorption.

BACKGROUND: Stabilizing blood levels with microemulsified cyclosporine A (CsA), administered in many pediatric kidney diseases, is important for effective immunosuppression and reduced nephrotoxicity. CsA is affected by total bile acids (TBAs); however, no reports have simultaneously measured both. We aimed to elucidate the hypothesized relationship between TBA levels and diurnal variation in CsA in children. METHODS: We retrospectively reviewed the medical records of children who were taking oral CsA for the treatment of kidney diseases between January 2016 and July 2021. They consumed four balanced meals and snacks during the day. CsA and TBA were measured twice, in pairs, before and at 0.5, 1, 1.5, 2, 3, and 4 h after oral administration in the morning and evening, and the four-h area under curve (AUC)0-4 of CsA and trough-to-peak ratio (TPR) of TBA were compared. RESULTS: Fifty-eight pairs were measured in total; 12 children had idiopathic nephrotic syndrome and 4 children had immunoglobulin A vasculitis with nephritis. The median age at measurement was 7.5 years and the dose of CsA was 3.8 mg/kg/day. The AUC0-4 (ng·h/mL) was significantly lower in the evening than in the morning (1,669 vs. 1,451, P < 0.001). The TPR of TBA was significantly higher in the evening than in the morning (0.14 vs. 0.25, P < 0.001). CONCLUSIONS: The low AUC0-4 and slow TBA secretion observed in the evening may be due to pediatric-specific dietary rhythms; thus, snack timing should be considered in children for stabilizing CsA levels.

Cyclosporine A C1.5 monitoring reflects the area under the curve in children with nephrotic syndrome: a single-center experience.

BACKGROUND: The currently used single-monitoring method for drug-blood-level evaluation in cyclosporine A (CsA) treatment for nephrotic syndrome (NS) was established through hourly measurements based on adult organ transplantation. However, the pharmacokinetics may differ due to different concomitant medications, age, and conditions. This study was conducted to determine the measurement timing that best reflects the CsA area under the curve (AUC) in pediatric NS. METHODS: This retrospective study included children aged 2-14 years who were started on CsA treatment for idiopathic NS during 2013-2020. AUC0-4 was calculated from 7 points, before and 0.5, 1, 1.5, 2, 3, and 4 h after administration. Mean values at each timing were compared with age-dependent different drug forms. Correlation between AUC0-4 and measurement timing was analyzed. RESULTS: There were 13 patients (11 boys) whose median age during testing was 7.3 years, and the total number of measurements was 94. The highest timing of CsA concentrations was found in C1 59.6%. The content liquid used at younger ages had a faster absorption time to peak value and lower blood concentration than those of capsules. Among the significant correlations observed, AUC0-4 and C1.5 showed the strongest significant correlation coefficient (r = 0.93, P < 0.001). CONCLUSION: In pediatric NS, CsA metabolism may be faster than that in previous organ transplantation. Compared with C2, C1.5 monitoring may result in better disease control as it can best reflect the AUC0-4 and peak values associated with side effects, which are indicators of therapeutic efficacy.