Too Much Salt to My Taste: An Entity to Think about in Neonatal Hypernatremia: A Case Report and Review of the Literature.

In exclusively breastfed newborns, hypernatremic dehydration is associated with a free water deficit secondary to insufficient fluid intake. Failure of newborns to regain their birth weight by the 10th day of life should be investigated urgently. In this report, we present a case of a 2 -week-old girl who presented to our institution for 30% weight loss and was found to have severe hypernatremic dehydration associated with acute renal failure (creatinine 4 mg/dL). Upon further investigation, the breast milk sodium content was found to be extremely elevated (90 mEq/L). To our knowledge, the following reported case of severe neonatal hypernatremic dehydration associated with acute renal failure has the most elevated breast milk sodium content, serum sodium, and serum creatinine levels described in the literature. Thus, hypernatremic dehydration secondary to elevated breast milk content should always be borne in mind and investigated whenever suspected.

NEK8-Associated Nephropathies: Do Autosomal Dominant Forms Exist?

INTRODUCTION: Nephronophthisis (NPHP) is a group of autosomal recessive renal diseases characterized by a reduced ability of the kidneys to concentrate solutes, chronic tubulointerstitial nephritis, and cystic kidney disease. It represents the most common genetic cause of childhood renal failure. To date, around 20 different genes, encoding primary cilia proteins, have been linked to NPHP. These contribute to one-third of cases with NPHP while the majority of patients remain molecularly undiagnosed. MATERIALS AND METHODS: Whole exome sequencing (WES) was carried out on a 2-year-old Lebanese boy with infantile NPHP characterized by multicystic kidney dysplasia, kidney insufficiency, and enlarged kidneys in addition to chronic anemia. The candidate variant, detected by WES, was then tested in the patient and his parents by Sanger sequencing. Copy number variation (CNV) analysis was subsequently performed in the proband. RESULTS: Our studies enabled the detection of a heterozygous de novo variant in NEK8 (NM_178170: p.Arg45Trp) in the proband. CNV analysis excluded the presence of big deletions or insertions in this gene. CONCLUSION: Here we report a de novo heterozygous variant in the NEK8 gene in infantile NPHP. This variant was previously detected at a de novo state in a patient presenting with the same clinical features as the proband. This suggests that autosomal dominant forms of NEK8-linked nephropathies may exist. Reporting further patients with NEK8 mutations is essential to confirm these findings and assess whether dominant forms of the disease are restricted to a specific mutational spot or are linked to variants scattered throughout the NEK8 gene.

Renovascular hypertension in children.

Renovascular disease accounts for 5 to 10% of all cases of hypertension in children. It is a serious, but potentially curable disease. The presenting blood pressure is usually very high and difficult to control. Renal angiography is the gold standard for diagnosis. Treatment with various antihypertensive drugs, angioplasty and surgery, provided by a multidisciplinary team of pediatric nephrologists, interventional radiologists and vascular surgeons offer a good long-term outcome for most affected children.

Inflammatory myofibroblastic tumor of the mesentery associated with high fever and positive Widal test.

Inflammatory myofibroblastic tumor (IMT) is associated in 15-30% of cases with systemic symptomatology, such as prolonged fever, weight loss, elevated erythrocyte sedimentation rate (ESR), anemia, thrombocytosis, and leukocytosis. We report the case of a 4-year-old Lebanese boy who presented with high-grade fever of long duration, and a single (unpaired) positive Widal agglutination test. Blood culture was negative. A diagnosis of typhoid fever was made. An abdominal (mesenteric) IMT was incidentally discovered, 30 days after the fever had appeared. After surgery, the fever disappeared immediately, and the ESR returned to normal. We strongly favor the possibility of a false positive Widal test, due to polyclonal increase in serum immunoglobulins, which often occurs in IMT. We also think that IMT might be a mimicker of typhoid fever, both clinically and serologically. Physicians, especially pediatricians practicing in endemic areas, should probably be aware of this mimicry.