Chronic Kidney Disease in Children Aged 6-15 Years and Associated Risk Factors in Apizaco, Tlaxcala, Mexico, a Pilot Study

INTRODUCTION

Tlaxcala, a small state in central Mexico, has the highest prevalence of chronic kidney disease (CKD) deaths in population aged 5-14 in Mexico, most of them with unknown etiology.

OBJECTIVE

To determine the prevalence of CKD in apparently healthy pediatric population in Apizaco, Tlaxcala.

METHODS

A cross-sectional pilot study was carried out in children deemed as healthy; subjects with previous diagnosis of CKD were excluded. Informed consent was obtained in all cases. A physical examination was performed, a questionnaire was applied. Blood and urine samples were obtained for serum creatinine, urinalysis, and microalbumin/creatinine ratio. A second and third evaluation was performed after 6 and 18 months in those found with urinary anomalies/CKD to confirm the diagnosis.

RESULTS

One hundred and nine subjects completed physical examination, which are the biological samples. Median age was 12 years. CKD stage 2 was confirmed in 5 subjects in the sixth month confirmation visit (4.6%). One patient accepted renal biopsy and Alport Syndrome was found. In a robust multivariate analysis, the risk factors related to reduction in the glomerular filtration rate were males -5.15 mL/min/1.73 m2 (p = 0.002), older participants as by -1.58 mL/min/1.73 m2 per year (p < 0.0001), and among participants living close to a river -3.76 mL/min/1.73 m2 (p = 0.033).

DISCUSSION/CONCLUSION

The prevalence of CKD in the population studied in Apizaco Tlaxcala was confirmed in 4.6 cases per 100 inhabitants between 6 and 15 years. Males, older age, and living close to a river were the risk predictive factors. More studies are needed to determine the causes of the high CKD prevalence in this population.

Increased cyclosporine bioavailability induced by experimental nephrotic syndrome in rats

Components of whole blood and plasma are highly altered during the presentation of nephrotic syndrome. The present study was aimed to explore the influence of nephrotic syndrome on the pharmacokinetics of cyclosporine (CsA) (10 mg/kg) administered i.v. to control or puromycin-induced nephrotic rats (P-NS). We found an increase in CsA bioavailability in the nephrotic group compared with controls. The area under the curve of blood CsA versus time (AUCiv) increased from 27.7 ± 5.3 to 60.6 ± 13.8 μg·h·mL–1in control and P-NS rats, respectively. The AUCivaugmentation was positively correlated with cholesterol levels. On the other hand, the total body clearance was significantly lower (0.38 ± 0.06 vs. 0.17 ± 0.03 L·(kg body mass)–1·h–1) and the volume of distribution at steady state (3.70 ± 0.52 vs. 2.85 ± 0.32 L/kg) was significantly smaller in nephrotic rats as compared with control. These pharmacokinetic changes lead to a longer terminal half-life of CsA in P-NS rats (11.8 ± 1.6 vs. 6.9 ± 0.91 h). We conclude that the physiopathologic changes induced by the nephrotic syndrome in P-NS animals result in a significant increase in CsA blood exposure by both the decrease in drug distribution and the reduction in elimination rate of CsA.

[Renal transplantation in children]

Despite being considered a high risk procedure, renal transplantation has been recognized for more than 20 years as the best therapeutic option for children with end-stage renal disease since it is superior than any available dialytic procedure in improving the neuropsychological development and the quality of life. Today pediatric patients have similar graft survival than adults, and 10 year-old children or less have better outcome than any other age group. These remarking results are due to the development of specialized pediatric transplant centers and research programs, improvement in the selection and preparation of donors and recipients, refinement of the surgical technique and the use of new immunossupressive drugs.

[Acute renal insufficiency]

The incidence of acute renal failure in children is higher due to the prevalence of diarrheal dehydration, use of nephrotoxic substances and sepsis. The occurrence in the newborn has increased, probably due to the large number of seriously sick infants maintained in neonatal intensive care units. Various laboratory examinations have been proposed as diagnostic indices of acute renal failure in children. Among these are the urine-to-plasma concentrations of urea and creatinine and the urine-to-plasma osmolality ratio. The fractional excretion of sodium and the so-called renal failure index are the most reliable of the diagnostic tests. The functional abnormalities and complications of acute renal failure include reduced glomerular filtration rate, retention of nitrogenous wastes, hyponatremia, hyperkalemia, metabolic acidosis, hypocalcemia, hyperphosphatemia and hypermagnesemia. The principles of management and treatment of complications are discussed.

[IgA nephropathy (Berger's disease) in children]

IgA nephropathy, also called Berger's disease, is characterized by recurrent gross hematuria or persistent microscopic hematuria, together with mesangial glomerular deposits of IgA found in the renal biopsy. Seven children with IgA nephropathy were studied. Most of them presented initially with recurrent macroscopic hematuria and low or moderate-grade proteinuria, without hypertension or renal function impairment. Only one patient presented with a rapidly progressive glomerulonephritis. Four patients did not receive any treatment; one of them is in remission, one has improved and two remain with moderate proteinuria and hematuria. One patient with significant proteinuria improved after prednisone and azathioprine treatment. The patient with rapidly progressive glomerulonephritis improved his renal function after oral prednisone and intravenous boluses of methylprednisolone and cyclophosphamide.

[Nephrotic syndrome associated with AIDS in children]

Several renal and renal-related disturbances have been described in patients with AIDS (acquired immune deficiency syndrome), in adults and children as well. These are mainly electrolyte and acid-base imbalance, acute renal failure and nephrotic syndrome. The latter is usually steroid non-responder. The renal histopathological lesions described more commonly are minimal change, mesangial hyperplasia and focal segmental glomerulosclerosis. Herein, we describe a 5 year-old with AIDS, that developed nephrotic syndrome, characterized by edema, ascites, hypoalbuminemia and massive proteinuria. A percutaneous renal biopsy showed mesangial proliferation. She did not respond to a 6 week treatment with prednisone. She died with sepsis after several viral and bacterial infections.

[Acute kidney failure due to stings by Africanized bees]

Africanized bees are unique in their aggressive behavior, characterized by massive attacks during which the victims are injected an important amount of venom. For this reason, Africanized bees are extremely dangerous. Their venom contains biological toxic substances, mainly mellitin, phospholipases, histamine, hyaluronidase and apamin. Non-sensitized persons that survive a massive attack may develop acute renal failure, as a consequence of the severe hemolysis, rhabdomyolysis and shock. These complications may lead to acute renal tubular necrosis. Also, the clinical pattern and treatment of the acute renal failure secondary to bee stings are discussed.

Obstructive aortic and renal thrombosis in the newborn--spontaneous recovery

A 13-day-old infant presented with acute renal failure secondary to a large thrombus formation involving the umbilical aorta and both renal arteries. The initial clinical manifestations were hematuria, followed by anuria, severe dehydration, grunting respirations, and cyanosis of her feet. She was treated with intravenous fluids and peritoneal dialysis. At the onset, there was no blood flow into the abdominal aorta or into the kidneys. Heparinization and fibrinolytic therapies were unsuccessful in dissolving the clot. However, the aortic clot recanalized spontaneously a few weeks later, but the renal arteries remained permanently occluded. Despite this, her kidneys showed blood flow bilaterally and she recovered her renal function, probably by reperfusing her kidneys through collateral circulation. Malignant hypertension ensued after improvement of renal function, but it could be controlled by appropriate antihypertensive therapy.

Unusual complication in a patient with renal transplantation: cerebral cysticercosis

A patient with cadaveric renal transplantation was diagnosed by brain-computed tomography and ELISA as having neurocysticercosis in the CSF. Complete cure was achieved after praziquantel therapy. Function of the allograft was not affected.

Adequacy of chronic peritoneal dialysis in low socioeconomic class uremic children

The ability to provide successful rehabilitation in 57 uremic children from a low socioeconomic background was prospectively evaluated by means of assessment of growth and development, incidence of complications, compliance, mortality rate and final outcome. Forty-three patients were on intermittent peritoneal dialysis (PD) and 14 on continuous ambulatory peritoneal dialysis (CAPD). The overall incidence of peritonitis was 5.6 episodes per patient-year; 41 patients are alive; 12 continue on intermittent dialysis; 16 received a renal allograft and 13 shifted to hemodialysis. Hypervolemia, sepsis due to peritonitis and abandonment of treatment were the main causes of death in 16 children. Malnutrition and non-compliance were the main factors leading to unsatisfactory rehabilitation.

Prednisone versus placebo in membranoproliferative glomerulonephritis: long-term clinicopathological correlations

Eighteen children with primary MPGN were included in a double blind controlled study. Experimental group received prednisone and control group received lactose. Studies of renal biopsy on admission, at 3 yr (17 pt) and 5 yr (8 pt) were performed. Mean time of observation in both groups was similar (6.5 yr). Four patients of the control group developed ESRD and none of the experimental group. Two patients of the control and one of the experimental group remitted. Serial immunopathological studies showed decreasing mesangial cellularity, thickening of the capillary walls and deposits in both groups. Increase tubulointerstitial alterations and percentage of global sclerotic glomeruli was generally observed except in cases in whom proteinuria disappeared. Our results suggest that prednisone therapy may retard the development of ESRD in children with MPGN. However, longer periods of observation and greater number of cases are necessary to confirm if this treatment in useful.