Infantile cystinosis: From dialysis to renal transplantation.

Cystinosis is an autosomal recessive, lysosomal storage disease characterised by the accumulation of the amino acid cystine in different organs and tissues. It is a multisystemic disease that can present with renal and extra-renal manifestations. In this report, we present the first case of transplanted nephropathic cystinosis in a Tunisian child. A 4-year-old Tunisian boy born to nonconsanguineous parents, was treated in our medical services in 1990 for cystinosis. Since the age of five months, he developed symptoms of severe weight loss, vomiting, dehydration, and polyuria. He manifested the Toni Debré Fanconi syndrome. Slit lamp examination of the anterior segment of both eyes revealed fine, shiny crystal-like deposits diffusely distributed in the corneal epithelium and the stroma. Our patient had renal failure. At the age of seven, he reached terminal chronic renal failure and was treated with peritoneal dialysis. Hemodialysis was started at the age of nine years. At the age of 13 years, he received a renal transplantation and was started on cysteamine 1999, five months after the renal transplantation. Currently, the patient is 28-year-old. The graft has survived 15 years after the transplantation. Renal functions were stable with a serum creatinine of 123 µmol/L at last follow-up.

Nephrocalcinosis in Tunisian children.

Background Nephrocalcinosis is rare in children. Its etiologies are multiple. The aim of this study was to analyze the etiology of nephrocalcinosis in Tunisian children. Methods This retrospective study was conducted in the department of pediatrics in Charles Nicolle Hospital during a period of 10 years (2001-2010). Results There were 40 children. The mean age was 3.5 years. The most common signs and symptoms at presentation were growth retardation (42.5%) and hematuria (53.8%). At presentation, renal failure was detected in 70% of patients. The diagnosis of nephrocalcinosis was performed by ultrasonography. The etiology of nephrocalcinosis included primary hyperoxaluria type 1 (65%) and distal renal tubular acidosis (20%). A progression to renal insufficiency was observed in 18 cases. Conclusion Primary oxaluria is the principal cause of nephrocalcinosis; early diagnosis and treatment are mandatory as they help limiting renal function deterioration.

Mycophenolate mofetil in treatment of childhood steroid-dependent nephrotic syndrome.

OBJECTIVES: To establish the efficacy of mycophenolate mofetil (MMF) in steroid dependent nephrotic syndrome and to determine the predictive factors for a good response. METHODS: retrospective hospital-based cohort study in the department of pediatric of Charles Nicolle hospital, between 2005 and 2012 included 30 children with steroid-dependent nephritic syndrome who were treated with MMF. RESULTS: A total of 30 patients (20 boys and 10 girls) were included. The mean age at the time of diagnosis was 5.45 years and treatment with MMF was performed at a mean age of 10.84 years. Side effects of steroid were found in 17 patients. Four patients had renal impairment (ciclotoxicity). The evolution of the disease was 5.45 years. The average rate of relapse was 1.75 relapses / year. The minimum dose of corticosteroids was 0.74 mg / kg / day. During MMF therapy, the average rate of relapse was 0.45 relapses / year (p<0.0001). The average residual steroid dose was 0.2 mg/kg/ day. Responding patients were younger at the onset of MMF (8.57 versus 12.83, p=0.009), had a short development period (3.75 vs 7.03 years, p=0.05), had not received cyclosporine (p=0.02). CONCLUSION: MMF allows steroid sparing and reduces the number of relapse. It is more effective than the patients are young, with short disease outcome and had not previously been treated with cyclosporine.

Primary hyperoxaluria in infants.

The infantile form of primary hyperoxaluria type-1 (PH-1) is characterized by a rapid progression to the end-stage renal disease (ESRD) due to both increased oxalate load and reduced glomerular filtration rate. In the literature, data on this form are limited. The purpose of this study is to analyze retrospectively the clinical, biological, and radiological features of children who were diagnosed with PH-1 during the 1(st) year of life. We reviewed the records of all children with PH-1 diagnosed and followed-up at our department between January 1995 and December 2013. Among them, only infants younger than 12 months of age were retrospectively enrolled in the study. Fourteen infants with the median age of two months were enrolled in the study. At diagnosis, 11 patients had ESRD. All patients had nephrocalcinosis and two of them had calculi. The diagnosis was established in nine patients on the basis of the positive family history of PH-1, bilateral nephrocalcinosis, and quantitative crystalluria. In four patients, the diagnosis was made with molecular analysis of DNA. Kidney biopsy contributed to the diagnosis in one patient. During follow-up, two patients were pyridoxine sensitive and preserved renal function. Seven among 11 patients who had ESRD died, four patients are currently undergoing peritoneal dialysis. Children with infantile PH and ESRD are at high risk of early death. Peritoneal dialysis is not a treatment of choice. Combined liver-kidney transplantation is mandatory.

[Etiologies of end-stage renal disease of children in Tunisia]. / Épidémiologie de l'insuffisance rénale terminale de l'enfant en Tunisie.

BACKGROUND: The end-stage renal disease (ESRD) in children has special features in terms of etiologies, therapeutic modalities and access to renal transplantation. In Tunisia, there are no data on the epidemiology of ESRD in children. The aim of our study was to describe epidemiology of ESRD among Tunisian children. METHODS: This retrospective study was conducted in pediatric departments in Charles-Nicolle Hospital, Tunis and Hedi Chaker hospital, Sfax, during a period of 15 years (1st January 1998-31st December 2013). We included children who develop ESRD before the age of 15 years. RESULTS: In total, 166 patients were included. The median duration of follow-up was 48 months. We collected respectively 24 children (14.5%) aged less than 2 years, 24 children (14.5%) aged between 2 and 6 years and 118 children (71%) older than 6 years. The sex ratio was equal to 1.4. The mean incidence was 4.25 cases per million children. The main causes were represented by congenital anomalies of the kidneys and urinary tract (35.5%), hereditary renal disease (31.3%) and glomerular kidney disease (9.6%). All patients were treated in kidney transplant dialysis programs; the main mode of dialysis was represented by peritoneal dialysis, which represented the initial dialysis mode in 81% of cases. The transition to hemodialysis was noted in 43.4% cases. Thirty-eight patients (22.8%) were transplanted. The mortality rate was 27.1%. The leading cause of death was cardiovascular diseases (37.7%) and infections (22.2%). CONCLUSION: The creation of a national registry of kidney disease in Tunisia is necessary for a better knowledge of needs for dialysis and renal transplantation in children.

Contribution of ultrasound scans in the first episode of urinary tract infection in children.

Background - Vesicoureteral reflux (VUR) is a common pediatric urologic disorder. After the first urinary tract infection (UTI), imaging studies are recommended, starting with a renal ultrasound (US) and voiding cystourethrography (VCUG). We propose to determine whether abnormalities found on US can help indicate the necessity of VCUG in children after the first urinary tract infection. Methods - A retrospective study included all children admitted with their first episode of urinary tract infection from January 2007 to December 2012. Results - A total of 311 children were included. The median age was 2.5 years, 72.3% were female. VUR Prevalence was 14%.  Forty-four patients were found to have VUR on VCUG, giving a prevalence of 14%. Of these 44 patients, 11 had grade I reflux, 6 had grade II reflux, 3 had grade III reflux, 15had grade IV reflux, and 9 had grade V reflux. Ultrasound findings were positive for VUR in 43 patients, 19 of them had RVU. Twenty five patients had a normal ultrasound but showed VUR on VCUG (11 had grade I reflux, six grade II reflux, three grade III reflux and five grade IV reflux).  The sensitivity and specificity of ultrasound in suggesting VUR were 43% and 91%, respectively. The positive predictive value of ultrasound in suggesting VUR was 44%; the negative predictive value was 91%. Conclusion - Renal ultrasound findings are specific for VUR in children with a first UTI, but no sensitive. Clinicians should consider renal ultrasound results to take decision on whether or not to proceed with a VCUG in the investigation of a first episode UTI in young children.

[Peritonitis in pediatric patients receiving peritoneal dialysis]. / Péritonite infectieuse sur cathéter de dialyse péritonéale chez l'enfant.

BACKGROUND: Peritonitis on catheter of dialysis represents the most frequent complication of the peritoneal dialysis (PD) in the pediatric population. It remains a significant cause of morbidity and mortality. In this study, we investigated the risk factors for peritonitis in children. METHODS: In this study, we retrospectively collected the records of 85 patients who were treated with PD within the past ten years in the service of pediatrics of the University Hospital Charles-Nicolle of Tunis. RESULTS: Peritonitis rate was 0.75 episode per patient-year. Notably, peritonitis caused by Gram-positive organisms were more common. Analysis of infection risk revealed three significant independent factors: the poor weight (P=0.0045), the non-automated PD (P=0.02) and the short delay from catheter insertion to starting PD (P=0.02). The early onset peritonitis was significantly associated with frequent peritonitis episodes (P=0.0008). The mean duration between the first and second episode of peritonitis was significantly shorter than between PD commencement and the first episode of peritonitis. We revealed a significant association between Gram-negative peritonitis and the presence of ureterostomy (0.018) and between Gram-positive peritonitis and the presence of exit-site and tunnel infections (0.02). Transition to permanent hemodialysis was needed in many children but no death occurred in patients with peritonitis. CONCLUSION: Considering the important incidence of peritonitis in our patients, it is imperative to establish a targeted primary prevention. Nutritional care must be provided to children to avoid poor weight. The automated dialysis has to be the modality of choice.

[Outcome of rapidly progressive glomerulonephritis post-streptococcal disease in children]. / Profil évolutif de la glomérulonéphrite rapidement progressive post-infectieuse de l'enfant.

BACKGROUND: Rapidly progressive glomerulonephritis is a rare form of postinfectious glomerulonephritis. The aim of this study was to describe the outcome of our patients with severe post-streptococcal glomerulonephritis. METHODS: This retrospective study was conducted in the department of pediatrics in Charles-Nicolle Hospital during a period of 13 years (1997-2009). RESULTS: Twenty-seven children were identified. The mean age was 8.7 years. All patients presented renal failure at presentation. The mean serum creatinine at presentation was 376.9 µmol/L. Six patients presented nephrotic syndrome. Twenty-six children had renal biopsies. Renal biopsies showed crescents in 24 cases. Eighteen children received pulse dose of corticosteroids (66.6%) and 6 children (22%) received pulse dose of corticosteroids and cyclophosphamide. Eleven patients required dialysis. At last follow-up, 22 patients (81.5%) had normal kidney function, 2 had renal dysfunction and 3 reached end stage renal disease. The only significant determinant for renal survival was the supportive dialysis (P=0.015). CONCLUSION: Rapidly progressive glomerulonephritis is uncommon. There have been significant advancements in supportive, as well as specific therapy, but the outcome continues to be poor.

Acute pancreatitis: a rare complication in a patient with senior loken syndrome.

INTRODUCTION: Senior-Loken syndrome is a rare entity that combines familial nephronophthisisand retinal dystrophy. It has an autosomal recessive inheritance pattern and is characterized by a chronic tubulointerstitial nephritis that progress to terminal renal failure during the first or second decades of life. Systemic associations of this syndrome include sensorineural hearing loss, liver fibrosis or cerebral vermis hypoplasia. Acute pancreatitis has not been previously reported in this syndrome. CASE REPORT: This is a 28- years-old patient who was diagnosed to have Senior Loken syndrome at the age of 10 years because of renal impairment and tapetoretinal degeneration and was later started on regular hemodialysis. He had no family history of renal disease, hypertriglyceridemia or cholelithiasis. He presented to our center complaining of acute abdominal pain and vomiting. He had abdominal tenderness without guarding. Investigations revealed a lipase level of 3856 I U/l and an abdominal CT scan showed features of acute pancreatitis. The abdominal ultrasound showed no biliary tree malformations or gallstone obstruction. He had no history of recent drug intake or alcohol consumption and his serum triglyceride level was normal. A diagnosis of moderate acute pancreatitis was made and the patient was managed conservatively with good outcome. CONCLUSION: Taking into consideration the uncertainty about the presence of liver fibrosis and the fact that imaging may have missed a passing gallstone, this case may indicate another rare systemic complication of Senior-Loken syndrome.

[Thromboembolic complications of childhood nephrotic syndrome]. / Complications thromboemboliques du syndrome nephrotique de l'enfant.

BACKGROUND: Vascular thrombosis in the childhood nephrotic syndrome is a rare event. It poses major diagnostic and therapeutic problems. The prognosis depends on early diagnosis and on precocious anticoagulation. The risk of extension of thrombosis and pulmonary embolism is real. AIMS: To consider the major thrombotic events associated with childhood nephrotic syndrome and to establish an appropriate preventive approach based on objective clinical and laboratory parameters. METHODS: This is a retrospective study of all cases of patients suffering from idiopathic nephrotic syndrome, during a period of 20 years, starting from January 1990 to December 2009. We selected six patients with vascular thrombosis. The diagnosis was confirmed by appropriate radiological investigation. RESULTS: Six cases of vascular thrombosis were identified among 260 cases of nephrotic syndrome collected during the period study. Patients are divided into five boys and one girl. The mean age was 13.3 years. The localisation of thrombosis is venous in all cases. One patient presented a massively fatal pulmonary embolism. Sinovenous thrombosis has been objectified in 3 patients who were all treated with a good therapeutic response. CONCLUSION: vascular thrombosis remains one of the most serious complications of nephrotic syndrome in children. Early diagnosis and precocious anticoagulation are essential for preventing the extension of thrombosis.