Hypernatremia in Newborns: A Practical Approach to Management.

Hypernatremia is a potentially serious condition in both term and preterm babies, which can lead to severe and permanent neurological damage. There are many physiological changes in sodium homeostasis that occur soon after birth. Understanding this physiological process, early anticipation of hypernatremia and familiarization with the neonatal management of hypernatremia can prevent mortality and long-term morbidity associated with this condition. This review aims to provide a practical and understandable approach to the diagnosis and management of hypernatremia in neonates.

Evaluation of Proteinuria and Hematuria in Ambulatory Setting.

Proteinuria and/or hematuria are common findings in ambulatory settings. Proteinuria can be glomerular and/or tubular in origin and it may be transient, orthostatic, or persistent. Persistent proteinuria may be indicative of a serious kidney pathology. Hematuria, which denotes the presence of an increased number of red blood cells in the urine, can be gross or microscopic. Hematuria can originate from the glomeruli or other sites of the urinary tract. Asymptomatic microscopic hematuria or mild proteinuria in an otherwise healthy child is less likely to be of clinical significance. However, the presence of both requires further workup and careful monitoring.

Treatment of severe edema in children with nephrotic syndrome with diuretics alone--a prospective study.

BACKGROUND AND OBJECTIVE: Severe edema in children with nephrotic syndrome (NS) may be associated with volume contraction (VC) or volume expansion (VE). Usually, severe edema in children is treated with intravenous (IV) albumin and diuretics, which is appropriate for VC patients. However, in VE patients, this can precipitate fluid overload. The objective of this study was to evaluate treatment of severe edema in NS with diuretics alone. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Thirty NS patients with severe edema were enrolled in this prospective study in two phases. VC was diagnosed based on fractional excretion of sodium (FeNa) <1%. VC patients received IV albumin and furosemide. VE patients received IV furosemide and oral spironolactone. On the basis of phase 1 observations, FeNa <0.2% identified VC in 20 phase 2 patients. RESULTS: All phase 1 patients had FeNa <1%. Phase 1 patients when reanalyzed based on a FeNa cutoff of 0.2%; it was noted that VC patients had higher BUN, BUN/creatinine ratio, urine osmolality, and lower FeNa and urine sodium compared with VE patients. Similar results were observed in phase 2. VC patients had significantly higher renin, aldosterone, and antidiuretic hormone levels. In phase 2, 11 VE patients received diuretics alone and 9 VC patients received albumin and furosemide. There was no difference in hospital stay and weight loss in VC and VE groups after treatment. CONCLUSIONS: FeNa is useful in distinguishing VC versus VE in NS children with severe edema. The use of diuretics alone in VE patients is safe and effective.

Two-dose daclizumab induction in pediatric renal transplantation.

DCZ, an IL-2 receptor antagonist, has been widely used for induction therapy in pediatric and adult solid organ transplantation. Originally, it was recommended as a five-dose regimen; however, fewer doses may be efficacious and less costly for prevention of rejection. There is limited experience with the use of fewer doses in pediatric renal transplantation. We retrospectively reviewed the outcomes of 26 primary pediatric renal transplants performed at a single center between June 2004 and May 2007 receiving induction therapy with two-dose DCZ (1.5 mg/kg preoperatively and day seven post-transplant). Maintenance immunosuppression included tacrolimus, MMF, and prednisone in all patients. Forty-six percent were African American and 92% were deceased-donor transplants. After a mean follow-up of 17.8 +/- 7.5 months, acute rejection was noted in 11.5% and graft survival was 92.3%. CMV infection occurred in 11.5%, but no case of BK nephropathy or post-transplant lymphoproliferative disorder was observed. Our preliminary results suggest that induction therapy with two-dose DCZ was convenient, economical, and effective in preventing rejection episodes without an increase in adverse events or hospital stay. Larger randomized clinical trials with longer duration of follow-up are needed to more fully validate the use of this regimen in pediatric renal transplantation.

Ceftriaxone induced hemolysis complicated by acute renal failure.

Over the last decade, second and third generation cephalosporins have been the most common drugs causing hemolytic anemia (HA). Of these cases, 20% have been attributed to ceftriaxone. The clinical presentation of ceftriaxone-induced HA is usually abrupt with sudden onset of pallor, tachypnea, cardio-respiratory arrest and shock. Acute renal failure (ARF) has been reported in 41% of such cases with a high fatality rate. We report a pediatric patient with ARF complicating ceftriaxone-induced HA who survived. Ceftriaxone is a commonly used drug, and early recognition of HA and institution of supportive care, including dialysis is likely to improve the outcome.

Serum osmolal gap in patients with idiopathic nephrotic syndrome and severe edema.

Pseudohyponatremia in idiopathic nephrotic syndrome with severe edema is attributed to hyperlipidemia that results in displacement of a portion of water phase of plasma. Current methods of measurement of serum electrolytes are unaffected by hyperlipidemia. In this report we demonstrate that patients with idiopathic nephrotic syndrome with severe edema and true hyponatremia may have an increased rather than normal osmolal gap. We believe that this could be secondary to non-Na+ and non-K+ osmoles in response to plasma-volume contraction secondary to hypoalbuminemia. This observation has implications for management of severe edema in such patients, because fluid restriction could increase their risk for pre-renal failure.

Intravenous immunoglobulin, HLA allele typing and HLAMatchmaker facilitate successful transplantation in highly sensitized pediatric renal allograft recipients.

The use of intravenous immunoglobulin (IVIG) in sensitized transplant candidates has resulted in reduced HLA antibody levels and shorter transplant wait times. In addition, the HLAMatchmaker program has been used to identify acceptable mismatches to permit transplantation in highly sensitized patients. We used IVIG desensitization in conjunction with high resolution HLA allele typing and HLAMatchmaker grading of donor offers to facilitate successful transplantation in two highly sensitized children who were awaiting second renal transplants. Both patients lost their initial transplant in <10 days to accelerated acute rejection, and were on dialysis for an average of 50 months with high panel reactive antibody (PRA) levels. They were started on monthly IVIG infusions (2 g/kg/dose). Within one wk following their third and fifth IVIG doses, both patients received a crossmatch compatible, deceased donor renal transplant selected by HLAMatchmaker as a suitable donor offer. Both patients remain rejection free with excellent renal function 19 and 15 months post-transplant, respectively. In conclusion, combining IVIG therapy and donor selection by HLA humoral epitope matching permitted successful transplantation of two highly sensitized children. Further studies in larger numbers of patients with longer follow-up are needed to determine the individual role played by, and relative importance of each component of this combined strategy.

Pasteurella multocida urinary tract infection in a pediatric patient with end-stage renal disease.

Pasteurella multocida is a Gram-negative bacillus that is part of the normal oral flora of cats and dogs. Most infections involving P. multocida are soft tissue infections after animal bites or scratches. We present a case of P. multocida urinary tract infection in a 13-year-old boy with end-stage renal disease receiving peritoneal dialysis. He was successfully treated with intravenous ampicillin-sulbactam followed by oral amoxicillin-clavulanate. Thirteen additional cases of P. multocida urinary tract infection (12 adults and one pediatric patient) reported in the literature were reviewed. Underlying medical illnesses and structural urologic abnormalities are risk factors.

MR angiography in the evaluation of a renovascular cause of neonatal hypertension.

Neonatal hypertension occurs in 2% of all infants and it is caused by renovascular abnormalities in 70% of these infants. The gold standard for diagnosing renovascular disease is conventional renal angiography. However, in neonates the procedure is not commonly used because of its invasive and technically challenging nature. MRI and MR angiography (MRA) are less invasive yet reliable means of detecting renovascular disease in adults. There is minimal literature on the use of MRI/MRA in neonatal hypertension. We report a neonate with hypertension secondary to a renovascular abnormality in which MRI/MRA was helpful in uncovering segmental renal artery stenosis. The infant underwent partial nephrectomy with subsequent resolution of his hypertension. Further studies are needed to validate the use of MRI/MRA in the evaluation of neonatal hypertension.

Calciphylaxis in pediatric end-stage renal disease.

Calciphylaxis is a rare, but life-threatening complication of end-stage renal disease (ESRD) that has been reported mostly in adult patients. The exact etiology is unknown, but the disease is commonly associated with a high calcium-phosphorus product and elevated levels of parathyroid hormone (PTH). We herein review the published reports on calciphylaxis in ESRD patients less than 18 years old and report the case of a patient with severe calciphylaxis who presented with lower extremity pain, muscle tenderness and difficulty in walking. The serum PTH was low, and the calcium-phosphorus product was normal. The diagnosis of calciphylaxis was confirmed by a muscle biopsy. Treatment with low calcium peritoneal dialysate and substitution of calcium-based phosphorus binders with sevelamer (Renagel) was unsuccessful. The patient's clinical condition progressed to extensive soft tissue calcification and ulcerating skin lesions. Nine months after the onset of symptoms, the patient died of cardiopulmonary arrest.