Hypercholesterolemia and glomerular diseases in urinary screening of school children

Review shows that lipid disorders are associated with endothelial but not renal dysfunction in children

AIM

We undertook this review to assess the effects of lipid metabolism abnormalities on endothelial and renal function in children.

METHODS

A search of relevant literature published in English from January 1988 to May 2018 was performed, and this included randomised controlled trials, observational cohort studies, systematic reviews and case reports.

RESULTS

The search process identified 2324 relevant studies and 29 were finally included. Noninvasive ultrasound markers of endothelial dysfunction, such as flow-mediated dilation and carotid intima-media thickness, were impaired in children with dyslipidaemia. Dietary interventions and statin therapy reversed the effects of dyslipidaemia on endothelial function in children. Most data from adult studies failed to prove a causative relationship between dyslipidaemia and renal disease progression or a beneficial effect of lipid-lowering treatment on renal outcomes. The limited paediatric data did not indicate dyslipidaemia as an independent risk factor for renal dysfunction, which was mainly estimated by cystatin C levels or proteinuria. Therefore, further investigation is needed to clarify a potential relationship.

CONCLUSION

In view of limited available paediatric evidence, dyslipidaemia may be adversely associated with endothelial function. However, the association between lipid metabolism disorders and renal function in childhood needs to be further investigated.

[Idiopathic nephrotic syndrome]

Nephrotic syndrome (NS) is defined by massive proteinuria and hypoalbuminemia, with resulting hyperlipidemia and edema. The most common cause of NS in children is idiopathic nephrotic syndrome (INS), also called nephrosis. Its annual incidence has been estimated to 1-4 per 100,000 children and varies with age, race, and geography. Many agents or conditions have been reported to be associated with INS such as infectious diseases, drugs, allergy, vaccinations, and malignancies. The disease may occur during the 1st year of life, but it usually starts between the ages of 2 and 7 years. INS is characterized by a sudden onset, edema being the major presenting symptom, but may rarely be discovered during a routine urine analysis. The disease may also be revealed by a complication such as hypovolemia, infection (pneumonia and peritonitis due to Streptococcus pneumoniae), deep-vein or arterial thromboses, and pulmonary embolism. Renal biopsy is usually not indicated in a child aged 1-10 years with typical symptoms and a complete remission with corticosteroids. Conversely, it is indicated in children under 1 year in case of macroscopic hematuria, hypertension, low C3 levels, persistent renal failure, or steroid resistance. Steroid therapy is applied in all children whatever the histopathology. Initial prednisone therapy in France consists of 60mg/m² administered daily for 4 weeks (maximum dose, 60mg/day), followed by alternate-day prednisone with tapering doses. Eight-five to 90 % patients are steroid-responsive and may relapse, but the majority still responds to steroids over the subsequent courses. Only 1-3 % of patients who are initially steroid-sensitive subsequently become steroid-resistant. Children with primary or secondary steroid-resistance are at risk of end-stage kidney disease. Symptomatic treatment includes salt restriction, fluid restriction when natremia is less than 125 meq/L, reduction of saturated fat and carbohydrates, calcium and vitamin D supplements, anticoagulation, and vaccination. Albumin infusions are only indicated in case of complications. Diuretics should be restricted to cases of severe edema, after hypovolemia has been corrected.

The influence of a long-term growth hormone treatment on lipid and glucose metabolism: a randomized trial in short Japanese children born small for gestational age

Background

Long-term growth hormone (GH) treatments in short children born small for gestational age (SGA) restore lipid metabolism, but also increase insulin resistance. The aim of this study was to evaluate the influence of long-term GH therapy on lipid and glucose metabolism as well as its dose dependency in short Japanese children born SGA.

Methods

Eighty Japanese children with a short stature who were born SGA participated in this study; 65 were treated with fixed GH doses of 0.033 (low) or 0.067 (high) mg/kg/day for 260 weeks; 15 were untreated controls in the first year and were randomized to one of the two treatment groups at week 52. Serum cholesterol, glucose and insulin levels were regularly measured. An oral glucose tolerance test (OGTT) was conducted annually.

Results

The mean age at the start of GH therapy was approximately 5.3 years. Serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in the high dose group significantly decreased over time during GH therapy. In both dose groups for TC, and in the high dose group for LDL-C, the higher the baseline values, the greater the decrease after 260 weeks. The rate of the decrease observed after 260 weeks in patients with high LDL-C levels was greater in the high dose group. Based on the results of OGTT, no patient was classified as being diabetic; however, annual increases were observed in post-OGTT insulin levels. After 260 weeks, the homeostasis model assessment as an index of insulin resistance (HOMA-IR) increased, suggesting that insulin resistance developed over time with the GH treatment, while 36.6 % of the subjects entered puberty.

Conclusions

Long-term continuous GH treatment for children born SGA may have a potentially beneficial effect on several parameters in lipid metabolism and does not adversely affect glucose metabolism.

Trial registration

GHLIQUID-1516, GHLIQUID-1517, Japan Pharmaceutical Information Center Clinical trial registration: JapicCTI-050132. Registered 13 September 2005. Retrospectively registered. JapicCTI-050137. Registered 13 September 2005. Retrospectively registered. ClinicalTrials.gov trial registration: NCT00184717. Registered 13 September 2005. Retrospectively registered.

A case of homozygous familial hypercholesterolemia with focal segmental glomerulosclerosis

Familial hypercholesterolemia (FH) is a common autosomal dominant inherited disorder characterized by increased levels of circulating plasma low-density lipoprotein cholesterol (LDL-C), tendon xanthomas, and premature atherosclerotic cardiovascular disease. Homozygous FH occurs in only one in a million people. Focal segmental glomerulosclerosis (FSGS) is clinically characterized by proteinuria, which is marked in the majority of cases and accompanied by nephrotic syndrome, high incidence of hypertension, and progression to renal failure. To our knowledge, we herein report for the first time a case of homozygous FH associated with FSGS. A seven-and-a-half-year-old boy was referred to our hospital due to cutaneous xanthomata and growth retardation. He had multiple nodular yellowish cutaneous xanthomatous lesions each 1 cm in size over his knees and sacral region. Laboratory data included cholesterol level of 1,050 mg/dl, low density lipoprotein cholesterol (LDL-C) 951 mg/dl, high-density lipoprotein cholesterol (HDL-C) 29 mg/dl, triglycerides 168 mg/dl, total protein 6.3 g/dl, and albumin 3.2 g/dl. Urinary protein excretion was 78 mg/m(2) per hour. A percutaneous renal biopsy was performed, and histological findings showed FSGS. Treatment with cholestyramine and atorvastatin was unsuccessful in terms of lowering lipids, and he was placed on weekly sessions of plasmapheresis. Total cholesterol was reduced from 1,050 mg/dl to 223 mg/dl, LDL-C from 951 mg/dl to 171 mg/dl, and urinary protein excretion from 78 mg/m(2) per hour to 42 mg/m(2) per hour after eight sessions of plasmapheresis. It is our belief that plasmapheresis is a treatment of choice in patients with FSGS associated with FH.