Elif Çomak

Assessment of left ventricular function by tissue Doppler echocardiography in pediatric chronic kidney disease

Abstract Background: Cardiovascular (CV) disease remains the most common cause of mortality in chronic kidney disease (CKD). Methods: In this cross-sectional study, 43 pediatric patients with CKD were divided into two groups according to their estimated glomerular filtration rate (eGFR): groups 1 and 2 (eGR; 29–75 and 15–29 mL/min/1.73 m2, respectively). M – mode, conventional pulsed wave Doppler (cPWD) echocardiography and tissue Doppler imaging (TDI) were performed in all patients and 16 healthy controls. Maximal early (E wave) and late (A wave) diastolic flow velocities were assessed by cPWD. Using TDI, the early (E′) and late (A′) diastolic filling velocities were recorded. Early and late diastoles were evaluated using E′ values and E/E′ ratios, respectively. Results: Left ventricular hypertrophy (LVH) was determined in 19/43 (44.2%) patients. The E/E′ ratio was significantly higher in group 2 than in group 1 and controls. E/E′ was found to be positively correlated with left ventricular mass (LVM) index, and negatively with hemoglobin (Hb) levels. Low Hb levels were only independent predictor of E/E′ (p = 0.001, β: −0.470, 95% CI: −0.764; −0.196). E′ ratio was significantly lower in both patient groups compared to the controls. Conclusions: LVH and diastolic dysfunction are already present in early stages of CKD. Treatment of risk factors, such as anemia, is important to improve the clinical outcome.

Epstein-Barr virus infection in children with renal transplantation: 17 years experience at a single center

Abstract Objectives: The aim of this study was to detect the frequency, time of occurrence, management and outcome of Epstein–Barr virus (EBV) infection and related complications in pediatric renal transplant recipients. Methods: Pediatric renal allograft recipients transplanted between August 1994 and December 2011 at our hospital was evaluated retrospectively. The patients were divided into two groups; Groups 1 and 2 were composed of patients transplanted before and after November 2007, respectively, when plasma EBV DNA levels were periodically measured. Results: The study included 166 children, 89 (53.6%) boys, with a mean age of 12.2 ± 3.8 years. Prior to transplantation, 144 patients (86.7%) were EBV seropositive. Within a median follow-up period of 36 months, 11 of 22 seronegative children (50%) developed primary EBV infection. EBV reactivation was observed in 23 of 144 children (15.9%). Two patients with primary infection developed post-transplant lymphoproliferative disorder, one of whom died. Elevated serum creatinine levels or graft loss were not observed in any patient with EBV reactivation. Conclusions: EBV DNA monitoring by PCR in high-risk pediatric renal transplant recipients will provide early diagnosis and treatment of EBV infections.

Magnesium excretion and hypomagnesemia in pediatric renal transplant recipients

Abstract Background: We investigated magnesium excretion and rate of hypomagnesemia in pediatric renal transplant recipients. Method: The medical records of 114 pediatric renal transplant recipients were retrospectively evaluated. After exclusion of 23 patients, 91 patients were included in the study. We recorded serum magnesium levels at the time of measurement of urine magnesium wasting. Results: Mean serum magnesium levels were 1.73 ± 0.22 mg/dL and 38 of the patients (41%) had hypomagnesemia. There was a negative correlation between serum magnesium levels and estimated glomerular filtration rate and serum tacrolimus trough level (r = −0.215, p = 0.040 and r = −0.409, p = 0.000, respectively). Also, there was a statistically significant positive correlation between serum magnesium levels and transplantation duration (r = 0.249, p = 0.017). Mean fractional magnesium excretion was 5.9 ± 3.7% and 59 patients (65%) had high magnesium excretion. There was a significant negative correlation between fractional magnesium excretion and estimated glomerular filtration rate (r = −0.432, p = 0.001). There was a significant positive correlation between fractional magnesium excretion and serum creatinine (r = 0.379 p = 0.003). Conclusion: Patients with higher tacrolimus trough blood levels, lower glomerular filtration rate and at early posttransplant period had risk of hypomagnesemia.

ATP6V1B1 mutations in distal renal tubular acidosis and sensorineural hearing loss: clinical and genetic spectrum of five families.

Abstract Distal renal tubular acidosis (DRTA) is characterized by tubular defects in urinary acidification and hyperchloremic metabolic acidosis, hypokalemia, hypercalciuria, hypocitraturia, nephrocalcinosis and nephrolithiasis. Mutations in ATP6V1B1 cause DRTA associated with sensorineural hearing loss. The objective of this multicenter study is to screen DRTA patients with sensorineural hearing loss for ATP6V1B1 gene mutations and present genotype/phenotype correlation. Clinical data in five unrelated consanguineous families with DRTA and hearing loss were obtained in Turkey. For mutation screening, all coding exons of ATP6V1B1 were PCR-amplified and sequenced from genomic DNA. In our cohort of five families, there were four different homozygous ATP6V1B1 mutations in affected individuals: c.91C>T (p.R31X), c.232G>A (p.G78R), c.497delC (p.T166RfsX9) and c.1155dupC (p.I386HfsX56). Our study shows that rare and family-specific variants in ATP6V1B1 are responsible for DRTA and sensorineural hearing loss syndrome in Turkey. While firm genotype–phenotype correlations are not available, detailed clinical and molecular analyses provide data to be used in genetic counseling.

A case report: hepatic posttransplant lymphoproliferative disorder in a non-liver transplant patient.

Posttransplant lymphoproliferative disorder (PTLD) is the most common malignancy in children after solid organ transplantation. We present a patient, who developed Epstein-Barr virus (EBV)-related PTLD in the liver after renal transplantation. A 10-year-old EBV-seronegative boy with cystinosis underwent a living related preemptive renal transplantation. He received antiviral prophylaxis with valacyclovir. At 5.5 months posttransplantation he displayed a primary EBV infection with an high fever, hepatosplenomegaly, monocytosis, and positive EBV DNA levels. Two months there after, a hypoechoic nodular 20-mm lesion in the left lobe of liver was detected on abdominal ultrasonography, performed because of anorexia and weight loss. EBV-DNA copy number was 7820 copies per milliliter. Liver biopsy showed a diffuse large B-cell lymphoma that was compatible with PTLD. We stopped all immunosupressive agents other than prednisolone. Chemotherapy consisting of two courses of cyclophosphamide, vincristine, prednisolone, and adriamycin was followed by rituximab. Within 2 months, the lesion resolved and within 18 months, he was free of disease.

Assessment of Spot Urine Sodium to Potassium Ratio in Obese Hypertensive Children

Amac: Hipertansiyon patogenezinde diyetle asiri sodyum ve dusuk potasyum aliminin iliskisinin arastirilmasi. Gerec ve Yontemler: Calismaya 6-18 yas arasinda 56 obez normotansif, 41 obez hipertansif hasta ve kontrol grubu olarak 29 saglikli cocuk calismaya dahil edilmistir. Ogleden sonraki idrar orneklerinde sodyum/potasyum orani ve Tanitabiyoempedans yontemi ile ayrica total vucut yag oranlari degerlendirilmistir. Bulgular: Hipertansif 41 obez hastanin 10’u ≤10 yas iken 31’i > 10 yas olarak bulundu. Insulin duzeyleri ve HOMA-IR indeksleri, obez normotansif ve hipertansif gruplarda sirasiyla16.7±8.3ve 15.9±7.9 U/ ml, 4.4±3.4 ve5.3±3.4 olarak bulundu, istatistiksel olarak anlamli fark saptanmadi. Idrar Na, K, Na/K ve mikroalbumin/ kreatinin oranlarinda da kontrol, OHT ve ONT gruplari arasinda istatistiksel olarak anlamli farklilik bulunmadi. Sonuc: Artmis tuzlu ve yagli yiyecek tuketimi, sedanter yasam, hipertansiyon ve iliskili hastaliklar acisindan neden olabilecek faktorlerdendir.

Delayed diagnosis of primary vesicoureteral reflux in children with recurrent urinary tract infections: Diagnostic approach and renal outcomes

OBJECTIVE In this study, we aimed to assess renal outcomes of delayed diagnosis of dilating primary vesicoureteral reflux (VUR) following recurrent febrile urinary tract infections (fUTIs) and its diagnostic imaging procedures. MATERIAL AND METHODS The medical records of patients who underwent ultrasonography (US), non- acute dimercaptosuccinic acid (Tc-99mDMSA) scintigraphy and voiding cystourethrography (VCUG), and who were older than 2 years at the time of VUR diagnosis were retrospectively reviewed. RESULTS A total of 32 children (female, n=27: 84.4%) with a mean age of 7.67±3.34 years at the time of diagnosis of VUR were included in the study. Grade III, IV, V VUR were found in 22%, 69%, and 9% of the patients, respectively. At the time of VUR diagnosis, abnormal US findings were detected in 75% of the cases. Tc-99mDMSA detected abnormalities in 83.9% (7 with a single scar, 7 with multiple lesions, 12 with reduced kidney function) of the patients. Estimated glomerular filtration rate of 3 patients with bilateral grade IV VUR was <75 mL/min/1.73 m2. In 5 patients (16%), VUR could not be predicted by US+DMSA scintigraphy (Grade IV VUR in 3 and Grade III in 2 cases ). The sensitivity in predicting VUR was 75.00% (95% CI: 56.60-88.54) and 83.87% (95% CI: 66.27-94.55), respectively, for US alone and combined US+DMSA. CONCLUSION VCUG should be performed routinely in addition to US and non-acute DMSA in all children referred with recurrent fUTIs. Awareness of childhood UTI in public and healthcare personnels should be increased in order to refer these patients at a early stage to pediatric urology and nephrology units.

A Patient With Coexistent Type 1 Diabetes Mellitus and ANCA-Negative Granulomatosis With Polyangiitis

158 ranulomatosis with polyangiitis (GPA), previously known as Wegener’s granulomatosis (WG) is a necrotizing vasculitis involving small and medium sized vessels with the formation of non-caseified granulomas in involved organs.1 It represents a systemic disease that may affect many organ systems together with formation of granulomatous inflammation, although upper-lower respiratory tract and renal involvement are typical for this disorder.2 In this report, we describe a child with type 1 diabetes mellitus who was diagnosed with GPA based on respiratory signs and symptoms. The coexistence of these two conditions has never been reported in our country. A Patient with Coexistent Type 1 Diabetes Mellitus and ANCA-Negative Granulomatosis with Polyangiitis

Proteinuria in a male adolescent with hearing loss: Answers

Question 1 The electron microscopy study revealed the presence of zebra bodies (lamellar lipid inclusion bodies) in the podocyte cytoplasm, which is pathognomonic for Fabry disease [1]. Since Fabry disease is very rarely encountered in pediatric nephrology practice, the symptoms of patients presenting with proteinuria and hearing loss are usually considered to be suggestive of Alport syndrome or of diseases affecting coenzyme Q10 metabolism. In our patient, the presence of proteinuria without hematuria should rule out Alport disease. Hematuria can also be observed in Fabry disease, although rarely, leading to confusion with glomerular diseases [2].

An adolescent presenting with acquired acute renal damage: Questions

A 16-year-old girl was admitted to the pediatric nephrology department following testing that detected azotemia and headache. She was the fourth child of the fourth pregnancy of non-consanguineous parents, and her past medical history was unremarkable. There was no history of renal disease in the family. Her height was 166 cm (75th percentile), weight was 56 kg (50th percentile), and blood pressure was 115/65 mmHg (95th percentile 128/ 78 mmHg). There was no evidence of dehydration or edema. Her physical examination was unremarkable. The results of the laboratory examination were: hemoglobin, 8.4 g/dl; leukocytes, 3200/mm; platelets, 184,000/ mm; ferritin, 25 (normal range 11–306) ng/ml; blood urea nitrogen (BUN), 108 mg/dl; serum creatinine, 14.8 mg/dl; sodium, 117 mEq/L; potassium, 13.6 mEq/ L; calcium, 8.93 mg/dl; phosphorus, 16.1 mg/dl; uric acid, 14.9 g/dl. Daily urine volume was 1650 ml/m/ day. The results of her urine analysis were: pH 5, density 1029, leukocyte esterase and nitrite negative and 12 leukocyte/HPF. Neither proteinuria nor hematuria was observed. Although she had hyperkalemia, the T wave, PR distance and QRS complex data were normal on electrocardiography (ECG) (Fig. 1). The laboratory tests were repeated in the intensive care unit (ICU) because this level of serum potassium was considered to be incompatible with life but the ECG findings were normal. Upon admission to the ICU, BUN was 11 mg/dl, serum creatinine was 0.78 mg/dl, sodium was 139 mEq/L, potassium was 4.8 mEq/L, calcium was 9 mg/dl, phosphorus was 4.3 mg/dl and uric acid was 5.8 g/dl. In the meantime, a large number of viable bacilli and cells similar to epithelial cells with a large cytoplasm were observed on peripheral blood smear prepared from the first sample (Fig. 2). Her acute phase reactants were normal, and she was also afebrile. Blood tests performed the next day were similar to those at the time of admission.