First episode of febrile urinary tract infection in children, detection and risk factors of kidney scarring: A prospective cohort study.

AIMS: This prospective study aimed to evaluate the characteristics and findings of children who presented with acute pyelonephritis (APN) and to determine the independent risk factors for kidney scarring. MATERIAL AND METHODS: Patients who satisfied the following criteria were enrolled in the study: first known episode of APN; at least two of the following findings: fever ≥ 38.5 °C, white blood cell count ≥ 10,000/mm3, erythrocyte sedimentation rate ≥ 20 mm/h, C-reactive protein ≥ 20 mg/dL; absence of congenital abnormalities or other kidney and systemic diseases, except vesicoureteral reflux (VUR); no APN relapses until the time of kidney scar detection. 99mTc-Dimercaptosuccinic acid kidney scintigraphy (99mTc-DMSA) was performed at admission, along with a kidney ultrasound. Follow-up 99mTc-DMSA took place after 6 months. Radiographic cystourethrography for VUR detection and grading was performed 1 month after the acute infection. RESULTS: We enrolled 70 children in the study. The kidney ultrasound failed to diagnose more than half of the cases of APN. VUR was found in 21.5% of children. 75% had findings of APN in the acute phase through 99mTc-DMSA, while in the second 99mTc-DMSA, there was a complete remission in 68% of them. Scars were observed more frequently in older children, children with VUR grade ≥ III, and children not on antibiotic prophylaxis. CONCLUSION: VUR did not appear to be associated with the first episode of APN, and children older than 1 year of age had a higher risk of scarring. Antibiotic prophylaxis may prevent kidney scarring due to host immunomodulatory effects, but more studies are needed so that conclusions can be drawn.

Α rare case of myopathy, lactic acidosis, and severe rhabdomyolysis, due to a homozygous mutation of the ferredoxin-2 (FDX2) gene.

Mitochondrial myopathy is a severe metabolic myopathy related to nuclear or mitochondrial DNA dysfunction. We present a rare case of mitochondrial myopathy, presented with multiple episodes of proximal muscle weakness, lactic acidosis, and severe rhabdomyolysis (CPK 319,990 U/L, lactic acid 22.31 mmol/L, and GFR 3.82 mL/min/1.73m2 ). She was hospitalized in the pediatric intensive care unit due to acute kidney injury, elevated blood pressure, and deterioration of respiratory and cardiac function. Investigation for inherited metabolic disorders showed elevated levels of ammonia, lactic acid to pyruvic acid ratio, and urine ketone bodies. Exome sequencing detected a homozygous pathogenic variant in FDX2 (ENST00000541276:p.Met4Leu/c.10A > T) and a heterozygous variant of uncertain significance in MSTO1 (ENST00000538143:p.Leu137Pro/c.410 T > C). After Sanger sequencing, the p.Met4Leu pathogenic variant in FDX2 (ENST00000541276:p.Met4Leu/c.10A > T) was identified in a heterozygous state in both her parents and sister. Recently, pathogenic variants in the FDX2 gene have been associated with mitochondrial myopathy, lactic acidosis, optic atrophy, and leukoencephalopathy. Only four reports of FDX2-related rhabdomyolysis have been described before, but none of the previous patients had hyperammonemia. This is a rare case of severe mitochondrial myopathy in a pediatric patient related to a pathogenic FDX2 variant, suggesting the need for genetic analysis of the FDX2 gene in cases of suspicion of mitochondrial myopathies.

The efficacy and safety of corticosteroids in pediatric kidney scar prevention after urinary tract infection: a systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: Acute pyelonephritis (APN) in pediatric patients may lead to kidney scarring and is one of the main causes of permanent kidney damage. The incidence of kidney scarring after one febrile urinary tract infection (UTI) is reported to range from 2.8 to 15%, with the percentage rising to 28.6% after ≥ 3 febrile UTIs. Corticosteroids may have a role in the reduction of kidney scar formation and urine cytokine levels. The possible benefit of adjuvant corticosteroid administration in the reduction of kidney scar formation in children with APN has been recently examined in randomized controlled trials (RCTs). OBJECTIVES: The aim of this meta-analysis was to provide a summary of the current literature about the efficacy and safety of adjuvant corticosteroid administration in the reduction of kidney scar formation in children with APN. DATA SOURCES: An extensive literature search through major databases (PubMed/MEDLINE and Scopus) was carried out for RCTs from inception until October 12, 2022, investigating the efficacy and safety of adjuvant corticosteroids in preventing kidney scarring in children with APN. A risk ratio with 95% CI was used for dichotomous outcomes. RESULTS: In total, 5 RCTs with 918 pediatric patients with APN were included in the study. Adjuvant corticosteroid treatment revealed a statistically significant reduction in kidney scarring (95% CI 0.42-0.95, p = 0.03), without increasing the risk of adverse events like bacteremia, prolonged hospitalization, or recurrence of UTI. LIMITATIONS: There were limitations regarding sample size (n = 498 children), different classes of corticosteroids (methylprednisolone or dexamethasone), different routes of corticosteroid administration (intravenous or oral), and different day courses (3-day or 4-day course). CONCLUSIONS: Adjuvant corticosteroid administration seems to have a beneficial effect on kidney scar reduction in children with APN. Future studies should focus on the evaluation of the efficacy and safety of corticosteroids in kidney scarring reduction after APN to strengthen the results of our study. A higher resolution version of the Graphical abstract is available as Supplementary information.

Acute Scrotal Pain and a Different Use of an Old Imaging Method.

ABSTRACT: The differential diagnosis of scrotal pain in childhood is a challenge for every primary care physician. We report the case of a 5-year-old boy presenting to the emergency department owing to acute left scrotal pain. Ultrasound screening revealed a Morgagni hydatid in the left testis, which was surgically removed. X-rays revealed microcalcifications of the cyst wall and stroma, signs indicative of chronic inflammation. Results of histological examination confirmed radiographic evaluation. No similar use of x-rays has been described in literature before, to the best of our knowledge. A brief discussion also follows about Morgagni hydatid in childhood.

Treatment and long-term outcome in primary nephrogenic diabetes insipidus.

BACKGROUND: Primary nephrogenic diabetes insipidus (NDI) is a rare disorder and little is known about treatment practices and long-term outcome. METHODS: Paediatric and adult nephrologists contacted through European professional organizations entered data in an online form. RESULTS: Data were collected on 315 patients (22 countries, male 84%, adults 35%). Mutation testing had been performed in 270 (86%); pathogenic variants were identified in 258 (96%). The median (range) age at diagnosis was 0.6 (0.0-60) years and at last follow-up 14.0 (0.1-70) years. In adults, height was normal with a mean (standard deviation) score of -0.39 (±1.0), yet there was increased prevalence of obesity (body mass index >30 kg/m2; 41% versus 16% European average; P < 0.001). There was also increased prevalence of chronic kidney disease (CKD) Stage ≥2 in children (32%) and adults (48%). Evidence of flow uropathy was present in 38%. A higher proportion of children than adults (85% versus 54%; P < 0.001) received medications to reduce urine output. Patients ≥25 years were less likely to have a university degree than the European average (21% versus 35%; P = 0.003) but full-time employment was similar. Mental health problems, predominantly attention-deficit hyperactivity disorder (16%), were reported in 36% of patients. CONCLUSION: This large NDI cohort shows an overall favourable outcome with normal adult height and only mild to moderate CKD in most. Yet, while full-time employment was similar to the European average, educational achievement was lower, and more than half had urological and/or mental health problems.

Ambulatory hemodynamic patterns, obesity, and pulse wave velocity in children and adolescents.

BACKGROUND: In recent years, pulse wave velocity (PWV) has emerged as a surrogate marker of cardiovascular disease in children with cardiovascular risk factors. The aims of the present study were to identify determinants of PWV in children according to their weight status and to investigate the role of peripheral blood pressure and central hemodynamic parameters in the association between PWV and obesity. METHODS: We included in the study healthy children and adolescents randomly selected from a school-based blood pressure screening study. All participants underwent ambulatory blood pressure monitoring and 24-h pulse wave analysis. RESULTS: Overweight and obese children had higher 24-h PWV, 24-h peripheral and central systolic blood pressure (SBP), and cardiac output than normal weight ones. Children with both overweight and hypertension presented the highest 24-h PWV values (p < 0.001). Peripheral and central SBP, body mass index (BMI), and hemodynamic parameters, including stroke volume, cardiac output, total peripheral resistance, and cardiac index, were all associated with 24-h PWV. However, in stepwise regression analysis, 24-h peripheral and central SBP and cardiac index, but not BMI, were independent predictors of 24-h PWV. There were statistically significant differences in 24-h blood pressure and hemodynamic parameters among those on the lower and highest 24-h PWV quartile, but there were no significant differences in BMI among 24-h PWV quartile groups. CONCLUSIONS: Arterial stiffness is higher in overweight and obese children in the co-presence of hypertension. Peripheral and central SBP are the main determinants of 24-h PWV independent of weight status. Graphical abstract.

Treatment and long-term outcome in primary distal renal tubular acidosis.

BACKGROUND: Primary distal renal tubular acidosis (dRTA) is a rare disorder, and we aimed to gather data on treatment and long-term outcome. METHODS: We contacted paediatric and adult nephrologists through European professional organizations. Responding clinicians entered demographic, biochemical, genetic and clinical data in an online form. RESULTS: Adequate data were collected on 340 patients (29 countries, female 52%). Mutation testing had been performed on 206 patients (61%); pathogenic mutations were identified in 170 patients (83%). The median (range) presentation age was 0.5 (0-54) years and age at last follow-up was 11.0 (0-70.0) years. Adult height was slightly below average with a mean (SD score) of -0.57 (±1.16). There was an increased prevalence of chronic kidney disease (CKD) Stage ≥2 in children (35%) and adults (82%). Nephrocalcinosis was reported in 88%. Nephrolithiasis was more common with SLC4A1 mutations (42% versus 21%). Thirty-six percent had hearing loss, particularly in ATP6V1B1 (88%). The median (interquartile range) prescribed dose of alkali (mEq/kg/day) was 1.9 (1.2-3.3). Adequate metabolic control (normal plasma bicarbonate and normocalciuria) was achieved in 158 patients (51%), more commonly in countries with higher gross domestic product (67% versus 23%), and was associated with higher height and estimated glomerular filtration rate. CONCLUSION: Long-term follow-up from this large dRTA cohort shows an overall favourable outcome with normal adult height for most and no patient with CKD Stage 5. However, 82% of adult patients have CKD Stages 2-4. Importance of adequate metabolic control was highlighted by better growth and renal function but was achieved in only half of patients.

A pediatric case of atypical hemolytic uremic syndrome (aHUS): Could any infection play a triggering role?

A 12-year-old boy was transferred to our pediatric department from a rural hospital for fever, cough, and vomiting associated with thrombocytopenia, non-immune hemolytic anemia, and acute kidney injury, leading to the diagnosis of hemolytic uremic syndrome (HUS). A nasopharyngeal swab and a lower respiratory sample detected Influenza A by polymerase chain reaction (PCR). The patient was treated with oseltamivir and intravenous fluids in addition to fresh frozen plasma (FFP). Enteropathogenic Escherichia coli (EPEC) was detected in a stool sample by PCR. Serum antibodies for Mycoplasma pneumoniae (IgM and IgG) and Helicobacter pylori (IgA and IgG) were increased. Further work-up revealed elevated serum C5b-9 suggesting a simultaneous viral and bacterial infection-mediated complement overactivation leading to the diagnosis of atypical HUS (aHUS). An association between aHUS and influenza A is reported in the literature, but the correlation of EPEC, Mycoplasma pneumoniae, and Helicobacter pylori with aHUS is not well-established. Fresh frozen plasma was administered for a total of 3 days, followed by clinical and laboratory improvement. The patient has remained asymptomatic until the latest follow-up, 5 months after discharge. This case demonstrates the potential triggering role of different pathogens in aHUS pathogenesis to raise awareness in the pediatric community.

Functional characterization of novel loss-of-function mutations in the vasopressin type 2 receptor gene causing nephrogenic diabetes insipidus.

BACKGROUND: X-linked nephrogenic diabetes insipidus (NDI) is a rare polyuric disorder caused by inactivating mutations in the arginine vasopressin receptor Type 2 (AVPR2) gene. METHODS: NDI patients from six unrelated families were subjected to mutational analysis of the AVPR2 gene. In-depth in vitro characterization of novel AVPR2 mutants by a combination of functional and immunological techniques provided further insight into molecular mechanisms causing receptor dysfunction. RESULTS: Mutational analysis revealed four novel (A89P, G107R, Q174R, W208X) and three recurrent (V277A, R337X, ΔR247-G250) mutations within the AVPR2 gene. One family carried the missense mutation R337X and a 12-bp deletion (ΔR247-G250), corresponding to a fragment in the third intracellular loop (ICL3), which was not genetically linked to R337X. The functionally tested missense mutations A89P, G107R and Q174R led to reduced receptor cell surface expression in transfected COS-7 cells, most probably due to misfolding and intracellular retention, and consequently to reduction or loss of agonist-mediated cyclic adenosine monophosphate formation. Deletion of R247-G250 had no effect on receptor function in vitro. Comparison with other mammalian AVPR2 orthologs showed that this part of the ICL3 is structurally not conserved and, therefore, less relevant for receptor function. In contrast, all missense mutations (A89P, G107R, Q174R, V277A) affect receptor positions that were fully preserved during mammalian evolution. CONCLUSION: Our results provide valuable information about residues critical for AVPR2 folding, trafficking and function and proof that these mutations are responsible for causing NDI in the affected subjects.

ANCA-associated glomerulonephritis/systemic vasculitis in childhood: clinical features-outcome.

BACKGROUND: Antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis and systemic vasculitis (AAGNV) is uncommon in childhood. METHODS: This is a retrospective study of AAGNV cases diagnosed over a 13-year period in a tertiary pediatric nephrology department. RESULTS: Thirteen cases of AAGNV were identified: seven Wegener granulomatosis (WG) and six microscopic polyangiitis (MPA). Acute renal failure/nephrotic range proteinuria (NRP) was found in 77 % of the patients (4 with WG, all with MPA). Eleven (85 %) patients showed necrotizing glomerulonephritis (NGN), with ≥50 % crescents identified in nine patients (69 %) (4 with WG, 5 with MPA). Treatment with methylprednisolone, cyclophosphamide and plasma exchange resulted in extra-renal remission and antibody reduction in all patients and renal function improvement/stabilization in 77 % of the patients. Three patients, all without oliguria at presentation and few sclerotic lesions, had normal renal function at follow-up. Chronic kidney disease (CKD) stages 2 and 3-4 were observed in four (WG) and three (MPA) patients, respectively. Three patients (23 %) developed end stage renal disease: two were MPA patients with severe presentation (markedly impaired glomerular filtration rate, oliguria, NRP, crescentic NGN, glomerular sclerosis) and one was a WG patient with extensive interstitial fibrosis/tubular atrophy. CONCLUSIONS: Severe renal involvement was more common in children with MPA than WG. Treatment with methylprednisolone, cyclophosphamide and plasma exchange induced extra-renal remission/serological response and renal function improvement/stabilization. Markedly decreased GFR, oliguria, NRP, and chronic glomerular lesions at presentation were predictors of poor outcome.

Interleukin-6 and interleukin-8 levels in the urine of children with renal scarring.

BACKGROUND: Acute pyelonephritis (APN) is one of the most significant bacterial infections in infancy and early childhood, and can lead to permanent kidney damage and chronic renal failure. OBJECTIVE: To evaluate interleukin-6 (IL-6) and interleukin-8 (IL-8) levels in the urine of children with renal scarring (RS), searching for clinical information about the immuno-inflammatory process that contributes to RS. METHODS: Urine concentrations of IL-6 and IL-8 were evaluated in 50 children, 33 with RS detected after an episode of acute pyelonephritis (group A) and 17 children with a history of acute pyelonephritis, but without RS (group B). These children were divided into four groups: group A(1), 23 children with RS and vesicoureteral reflux (VUR); group A(2), 10 children with RS without VUR; group B(1), 13 children without RS and without VUR; group B(2), 4 children without RS, but with VUR. None of them had had urinary tract infection for a minimum of 6 months. To avoid dilution effects, urinary levels of IL-6 and IL-8 were expressed as the ratio of cytokine to urinary creatinine (pg/mg). RESULTS: Urinary IL-8 levels were below the lower detection limit in all samples. IL-6 was detectable in the majority of children with RS and below the detection limits in the urine samples of children without RS. There were no statistically significant differences between urinary interleukin-6 levels in children with and those without VUR. There was a significant relationship between the grade of renal scars, the time passed since the last episode of acute pyelonephritis and the urinary levels of IL-6 (p < 0.0001 and p < 0.04 respectively). CONCLUSION: Further experimental studies are required to demonstrate the correlation between histopathology and urinary cytokine levels.

A neonate with intrauterine growth restriction and pseudo-Bartter syndrome due to severe maternal eating disorder: A case report.

Maternal diet before and during pregnancy plays an important role for the developing fetus. Any eating disorder in this period can cause transient or/and permanent negative effects on the mother and her offspring.

The Role of TLR4 Asp299Gly and TLR4 Thr399Ile Polymorphisms in the Pathogenesis of Urinary Tract Infections: First Evaluation in Infants and Children of Greek Origin.

Urinary tract infections are one of the most common and serious bacterial infections in a pediatric population. So far, they have mainly been related to age, gender, ethnicity, socioeconomic level, and the presence of underlying anatomical or functional, congenital, or acquired abnormalities. Recently, both innate and adaptive immunities and their interaction in the pathogenesis and the development of UTIs have been studied. The aim of this study was to assess the role and the effect of the two most frequent polymorphisms of TLR4 Asp299Gly and Thr399Ile on the development of UTIs in infants and children of Greek origin. We studied 51 infants and children with at least one episode of acute urinary tract infection and 109 healthy infants and children. We found that 27.5% of patients and 8.26% of healthy children carried the heterozygote genotype for TLR4 Asp299Gly. TLR4 Thr399Ile polymorphism was found to be higher in healthy children and lower in the patient group. No homozygosity for both studied polymorphisms was detected in our patients. In the group of healthy children, a homozygote genotype for TLR4 Asp299Gly (G/G) as well as for TLR4 Thr399Ile (T/T) was showed (1.84% and 0.92 respectively). These results indicate the role of TLR4 polymorphism as a genetic risk for the development of UTIs in infants and children of Greek origin.

Comorbid presentation of syringomyelia and Guillain-Barre syndrome, attributed to mycoplasma, in a 6-year-old female patient.

Syringomyelia is the development of a fluid-filled cavity or syrinx within the spinal cord that can cause loss of sensation and muscle spasticity. Guillain-Barre syndrome (GBS) is a postinfection autoimmune disease, classified as an acute polyneuropathy. This report describes the emergency admission of a 6-year-old girl presenting with sudden pallor and pain in both lower limbs. The patient's reflexes were normal, as were the results of her sonography, radiography and biochemical tests; however, spinal MRI revealed extensive compartmentalised syringomyelia extending from C2 to T3. A sensory and motor nerve conduction study revealed a demyelinating type motor polyneuropathy which, along with positive Mycoplasma pneumoniae test, was suggestive of GBS. Intravenous immunoglobulin infusion showed excellent results. In conclusion, we report a rare paediatric case of syringomyelia coexisting with GBS. It is important to bear in mind the possibility of other coexisting diseases even if MRI reveals definitive characteristics of another condition.

Spine pathology in a girl with upper limb pain: A co-incidence or a causal relationship?

A 10-year-old girl was admitted to the Emergency Department due to a history of intermittent pain located in the left radiocarpal joint for a month, as well as in the interphalangeal joints of the left hand without any additional symptoms. Clinical examination revealed mild sensory deficits and diminished muscle strength of the left upper limb without any other pathologic findings. A Magnetic Resonance Imaging scan of the brain and spinal cord was performed, which confirmed a diagnosis of thoracic syringomyelia. We briefly discuss specific traits and diagnostic challenges of this entity in childhood. Our case highlights the difficulty in efficiently correlating a pathologic imaging finding with clinical neurologic symptoms and signs, as well as the value of a thorough clinical neurological evaluation. Furthermore, a clear discrimination of a causal relationship against an incidental co-existence of a radiological finding and a specific symptom is not always possible.

Altered Expression of TLR2 and TLR4 on Peripheral CD14+ Blood Monocytes in Children with Urinary Tract Infection.

Urinary tract infection (UTI) is the second most common bacterial infection, after otitis media, in infants and children. The mechanisms of disease susceptibility and the role of immunity in the pathogenesis of UTI in children have been evaluated. In recent years, Toll-Like Receptors (TLRs) have been recognized as specific components of the innate immune system constituting important mediators in host immune recognition. The aim of the present study was to determine ΤLR2 and TLR4 expression during the acute phase of UTI in infants and children by measuring the CD14/TLR2 and CD14/TLR4 expression on monocytes. We also attempted to compare the TLRs expression with the immunological status of the patients to healthy children. The study group consisted of 60 children (36 females and 24 males) and the control group included 60 age-matched pediatric subjects (27 females and 33 males). In our study, no antibody deficiency was found either in the children with UTI or in healthy subjects. There might be a connection between low IgA, IgG, and IgG subclasses serum levels and UTI as there was a statistically significant difference between patients and healthy children. A higher expression of CD14/TLR2 was revealed in patients (90,07%) compared to controls (85,48%) as well as CD14/TLR4 in patients (90,53%) compared to controls (87,25%) (statistically significant difference, p < 0,05). The results of this study could provide new understanding of UTIs' pathogenesis in children.

Evidence for treatable inborn errors of metabolism in a cohort of 187 Greek patients with autism spectrum disorder (ASD).

We screened for the presence of inborn errors of metabolism (IEM) in 187 children (105 males; 82 females, ages 4-14 years old) who presented with confirmed features of autism spectrum disorder (ASD). Twelve patients (7%) manifested increased 3-hydroxyisovaleric acid (3-OH-IVA) excretion in urine, and minor to significant improvement in autistic features was observed in seven patients following supplementation with biotin. Five diagnoses included: Lesch Nyhan syndrome (2), succinic semialdehyde dehydrogenase (SSADH) deficiency (2), and phenylketonuria (1) (2.7%). Additional metabolic disturbances suggestive of IEMs included two patients whose increased urine 3-OH-IVA was accompanied by elevated methylcitrate and lactate in sera, and 30 patients that showed abnormal glucose-loading tests. In the latter group, 16/30 patients manifested increased sera beta hydroxybutyrate (b-OH-b) production and 18/30 had a paradoxical increase of sera lactate. Six patients with elevated b-OH-b in sera showed improved autistic features following implementation of a ketogenic diet (KD). Five patients showed decreased serum ketone body production with glucose loading. Twelve of 187 patients demonstrated non-specific MRI pathology, while 25/187 had abnormal electroencephalogram (EEG) findings. Finally, family history was positive for 22/187 patients (1st or 2nd degree relative with comparable symptomatology) and consanguinity was documented for 12/187 patients. Our data provide evidence for a new biomarker (3-OH-IVA) and novel treatment approaches in ASD patients. Concise 1 sentence take-home message: Detailed metabolic screening in a Greek cohort of ASD patients revealed biomarkers (urine 3-hydroxyisovaleric acid and serum b-OH-b) in 7% (13/187) of patients for whom biotin supplementation or institution of a KD resulted in mild to significant clinical improvement in autistic features.