Predicting graft survival in paediatric kidney transplant recipients using machine learning.

BACKGROUND: Identification of factors that affect graft survival in kidney transplantation can increase graft survival and reduce mortality. Artificial intelligence modelling enables impartial evaluation of clinician bias. This study aimed to examine factors that affect the survival of grafts in paediatric kidney transplantation through the use of machine learning. METHODS: A retrospective review was conducted on records of paediatric patients who underwent kidney transplantation between 1994 and 2021 and had post-transplant follow-up > 12 months. The nearest neighbour method was used to impute missing fields from a total of 48 variables in the dataset. Models including Naive Bayes, logistic regression, support vector machine (SVM), multi-layer perceptron, and XGBoost were trained to predict graft survival. The study used 80% of the patients for training and the remaining 20% for testing. Modelling success was evaluated based on accuracy and F1 score metrics. RESULTS: The study analysed 465 kidney transplant recipients. Of these, 56.7% were male. The mean age at transplantation was 12.08 ± 5.01 years. Of the kidney transplants, 73.1% (n = 339) were from living donors, 34.5% (n = 160) were pre-emptive transplants, and 2.2% (n = 10) were second-time transplants. The machine learning model identified several features associated with graft survival, including antibody-mediated rejection (+ 0.7), acute cellular rejection (+ 0.66), eGFR at 3 years (+ 0.43), eGFR at 5 years (+ 0.34), pre-transplant peritoneal dialysis (+ 0.2), and cadaveric donor (+ 0.2). The successes of the logistic regression and SVM models were similar. The F1 score was 91.9%, and accuracy was 96.5%. CONCLUSION: Machine learning can be used to identify factors that affect graft survival in kidney transplant recipients. By expanding similar studies, risk maps can be created prior to transplantation.

Therapeutic apheresis: is it safe in children with kidney disease?

BACKGROUND: Therapeutic apheresis (TA) is already used to treat various diseases in the field of nephrology. The aim of this study was to evaluate the frequency and types of complications that occur during TA in children with kidney disease. METHODS: Records of children (≤ 18 years) who underwent TA between 2007 and 2022 were retrospectively reviewed. Children with missing data and those with a diagnosis of nonnephrological disease were excluded. RESULTS: A total of 1214 TA sessions, including 1147 therapeutic plasma exchange (TPE) sessions and 67 immunoadsorption (IA) sessions, were performed on the 108 patients enrolled in the study. Forty-seven percent of the patients were male, and the mean age was 12.22 ± 4.47 years. Posttransplant antibody-mediated rejection (64.8%) and hemolytic uremic syndrome (14.8%) were the most common diagnoses indicating TA. Overall, 17 different complications occurred in 58 sessions (4.8%), and 53 sessions (4.6%) were not completed because of these complications. The distribution of complications among the patients was as follows: 41.4% had technical complications, 25.9% had allergic complications, and 32.7% had others. The most common technical complication was insufficient flow (37.5%). The incidence of complications was greater in patients aged 3-6 years than in patients in the other age groups (p = 0.031). The primary disease, type of vascular access, and rate of fresh frozen plasma/albumin use were similar between patients with and without complications (p values of 0.359 and 0.125 and 0.118, respectively). CONCLUSIONS: Our study showed that complications occurred in only 4.8% of TA sessions. The most common complication was technical problems.

Low C3 in a 4-month-old baby: is it a problem?

A 4-month-old male baby was admitted because his father and uncles had chronic kidney disease. His father was diagnosed with membranoproliferative glomerulonephritis at the age of 5, underwent a kidney transplant at the age of 22, and lost the graft due to recurrence of the disease. In contrast, the young uncle was diagnosed with C3 glomerulopathy and mycophenolate mofetil and eculizumab were initiated early. It was remarkable that our patient had normal kidney function and urine analyses but low serum C3 level (0.56 g/L; N, 0.9-1.8 g/L). In the disease-associated clinical exome analysis, a heterozygous change in the CFH gene was found. The same mutation was found homozygous in the uncle. In genetically inherited diseases, findings may occur sequentially; early screening of at-risk individuals contributes to kidney survival.

Characteristics and predictors of chronic kidney disease in children with myelomeningocele: a nationwide cohort study.

BACKGROUND: Myelomeningocele (MMC) is highly prevalent in developing countries, and MMC-related neurogenic bladder is an important cause of childhood chronic kidney disease (CKD). This nationwide study aimed to evaluate demographic and clinical features of pediatric patients with MMC in Turkey and risk factors associated with CKD stage 5. METHODS: Data from children aged 0-19 years old, living with MMC in 2022, were retrospectively collected from 27 pediatric nephrology centers. Patients > 1 year of age without pre-existing kidney abnormalities were divided into five groups according to eGFR; CKD stages 1-5. Patients on dialysis, kidney transplant recipients, and those with eGFR < 15 ml/min/1.73 m2 but not on kidney replacement therapy at time of study constituted the CKD stage 5 group. RESULTS: A total of 911 (57.8% female) patients were enrolled, most of whom were expectantly managed. Stages 1-4 CKD were found in 34.3%, 4.2%, 4.1%, and 2.4%, respectively. CKD stage 5 was observed in 5.3% of patients at median 13 years old (range 2-18 years). Current age, age at first abnormal DMSA scan, moderate-to-severe trabeculated bladder on US and/or VCUG, and VUR history were independent risk factors for development of CKD stage 5 (OR 0.752; 95%; CI 0.658-0.859; p < 0.001; OR 1.187; 95% CI 1.031-1.367; p = 0.017; OR 10.031; 95% CI 2.210-45.544; p = 0.003; OR 2.722; 95% CI 1.215-6.102; p = 0.015, respectively). Only eight CKD stage 5 patients underwent surgery related to a hostile bladder between 1 and 15 years old. CONCLUSION: MMC-related CKD is common in childhood in Turkey. A proactive approach to neurogenic bladder management and early protective surgery in selected cases where conservative treatment has failed should be implemented to prevent progressive kidney failure in the pediatric MMC population in our country.

COVID-19 in pediatric nephrology centers in Turkey.

BACKGROUND: There is limited data on COVID-19 disease in children with kidney disease. We aimed to investigate the characteristics and prognosis of COVID-19 in pediatric nephrology patients in Turkey. METHODS: This was a national, multicenter, retrospective cohort study based on an online survey evaluating the data between 11th March 2020 and 11th March 2021 as an initial step of a detailed pediatric nephrology COVID-19 registry. RESULTS: Two hundred and three patients (89 girls and 114 boys) were diagnosed with COVID-19. One-third of these patients (36.9%) were between 10-15 years old. Half of the patients were on kidney replacement therapy: kidney transplant (KTx) recipients (n = 56, 27.5%), patients receiving chronic hemodialysis (n = 33, 16.3%) and those on peritoneal dialysis (PD) (n = 18, 8.9%). Fifty-four (26.6%) children were asymptomatic. Eighty-two (40.3%) patients were hospitalized and 23 (28%) needed intensive care unit admission. Fifty-five percent of the patients were not treated, while the remaining was given favipiravir (20.7%), steroid (16.3%), and hydroxychloroquine (11.3%). Acute kidney injury developed in 19.5% of hospitalized patients. Five (2.4%) had MIS-C. Eighty-three percent of the patients were discharged without any apparent sequelae, while 7 (3.4%) died. One hundred and eight health care staff were infected during the study period. DISCUSSION: COVID-19 was most commonly seen in patients who underwent KTx and received HD. The combined immunosuppressive therapy and frequent exposure to the hospital setting may increase these patients' susceptibility. Staff infections before vaccination era were alarming, various precautions should be taken for infection control, particularly optimal vaccination coverage.

Comparison of ESHG2016 and AAP2017 hypertension guidelines in adolescents between the ages of 13 and 16: effect of body mass index on guidelines.

OBJECTIVE: The diagnosis of hypertension in adolescents aged ≥13 and <16 years is based on the percentile according to age, gender, and height in the European Society of Hypertension guidelines guideline; whereas, the American Academy of Pediatrics guideline uses blood pressure above 130/80 mmHg as a single criterion. Therefore, this study aimed to evaluate the compatibility of these two guidelines in adolescents aged ≥13 and <16 years. METHODS: This study was designed by retrospectively screening the records of 395 adolescents with both office and 24-hour ambulatory blood pressure measurements. Each blood pressure measurement was classified according to both the ESGH2016 and AAP2017 guidelines. Patients were divided into three subgroups according to body mass index. Cohen's kappa analysis was used to evaluate the agreement between the two guidelines. RESULTS: The majority of adolescents were normotensive according to both guidelines, 55.9% by ESHG2016 and 43.1% by AAP2017. For the whole group, the frequency of hypertension was 32.4% with ESHG2016 and 34.4% with AAP2017; while, in obese patients, hypertension frequencies were 38.8% and 43.3%, respectively. The diagnosis of hypertension was demonstrated with the two guidelines, and there was significant agreement at a substantial level, both for the obese subgroup and the whole study group (kappa value = 0.738 and 0.785, respectively). The frequency of white-coat hypertension was higher with the AAP2017 guideline (28.1% versus 16.2%, p < 0.001). CONCLUSION: With our experience in this single-centre study, it seems that both the AAP2017 and the ESHG2016 guidelines can be used in the diagnosis of hypertension in adolescents.

Evaluation of non-infectious complications of peritoneal dialysis in children: a multicenter study.

BACKGROUND: Peritoneal dialysis (PD) is the most common kidney replacement therapy in children. Complications associated with PD affect treatment success and sustainability. The aim of this study was to investigate the frequency of PD-related non-infectious complications and the predisposing factors. METHODS: Retrospective data from 11 centers in Turkey between 1998 and 2018 was collected. Non-infectious complications of peritoneal dialysis (NICPD), except metabolic ones, in pediatric patients with regular follow-up of at least 3 months were evaluated. RESULTS: A total of 275 patients were included. The median age at onset of PD and median duration of PD were 9.1 (IQR, 2.5-13.2) and 7.6 (IQR, 2.8-11.9) years, respectively. A total of 159 (57.8%) patients encountered 302 NICPD within the observation period of 862 patient-years. The most common NIPCD was catheter dysfunction (n = 71, 23.5%). At least one catheter revision was performed in 77 patients (28.0%). Longer PD duration and presence of swan neck tunnel were associated with the development of NICPD (OR 1.191; 95% CI 1.079-1.315, p = 0.001 and OR 1.580; 95% CI 0.660-0.883, p = 0.048, respectively). Peritoneal dialysis was discontinued in 145 patients; 46 of whom (16.7%) switched to hemodialysis. The frequency of patients who were transferred to hemodialysis due to NICPD was 15.2%. CONCLUSIONS: Peritoneal dialysis-related non-infectious complications may lead to discontinuation of therapy. Presence of swan neck tunnel and long duration of PD increased the rate of NICPD. Careful monitoring of patients is necessary to ensure that PD treatment can be maintained safely.

Assesment of colistin related side effects in premature neonates.

BACKGROUND: Colistin is an antibiotic in the polymyxin group and is especially important in the elimination of multi-drug resistant gram negative bacteria. To date, there are many studies investigating colistin related side effects, especially nephrotoxicity. However, there are few studies involving premature neonates, and this study aimed to investigate the side effects of colistin in this particular patient group. METHODS: Between January 2016 and May 2019, the medical records of premature neonates treated with colistin were retrospectively reviewed. The diagnosis of acute kidney injury (AKI) was performed according to the modified neonatal KDIGO criteria. Serum electrolyte levels were recorded at the initiation of colistin treatment and 4-7 days after. RESULTS: A total of 47 premature neonates; with a median gestational age of 27 weeks and median weight of 970 g at birth were included in the study. The median postnatal day of colistin initiation was 24 days and mean duration of colistin therapy was 15.95 ± 3.70 days. Colistin was combined with aminoglycosides in 44.6% of the patients. Acute kidney injury was documented in 17.0% of premature neonates. (n = 6 for stage 1, n = 2 for stage 2, none of the patients had stage 3). In univariate analysis, gestational age and concomitant aminoglycoside use were associated with AKI development (OR, 0.446; 95% CI 0.238-0.832; p = 0.011 and OR, 1.324; 95% CI 1.023- 7.584; p = 0.024). Mean magnesium level significantly decreased after colistin treatment (1.70 ± 0.84 vs. 1.57 ± 0.29, p = 0.017) and the frequency of hypomagnesemia increased after colistin use (78.7% vs. 91.5%, p = 0.031). Frequency of elevated AST increased from 23.4% to 44.7% following colistin use (p = 0.031). CONCLUSIONS: Colistin-related side effects observed in premature neonates are not as common as in pediatric patients. Electrolyte imbalance is observed more frequently in this age group following colistin use. We suggest strict serum electrolyte level monitoring, especially magnesium, in premature neonates that are receiving colistin.