Protective Role of Apelin Against Cyclosporine-Induced Renal Tubular Injury in Rats.

BACKGROUND: Cyclosporine (CsA) usually reduces glomerular filtration rate (GFR) but also can induce tubular injury without resulting in GFR reduction. Apelin is an endogenous ligand for the apelin receptor and has diverse physiologic roles related to hemodynamic or metabolic processes. We investigated the renoprotective role of apelin against CsA-induced tubular toxicity in rats. METHODS: Rats were given CsA (15 mg/kg/day) and/or apelin-13 (15 µg/kg/day) for 7 days via subcutaneous injection. We performed serum and urinary assays of creatinine and neutrophil gelatinase-associated lipocalin (NGAL) to estimate renal injury and performed Western blotting for endothelial nitric oxide synthase and nuclear factor of activated T-cell cytoplasmic 1 (NFATc1) to document the underlying mechanism. RESULTS: The CsA-treated group showed increased urinary creatinine excretion, polyuria, and renal glycosuria without GFR reduction, suggesting adequate CsA-induced renal tubular injury. Urinary NGAL excretion also increased significantly in the CsA group. Conversely, apelin attenuated CsA-induced tubular injury and had no effect on urinary NGAL excretion. In histopathologic examination, the apelin-treated group had lower tubulo-interstitial injury scores compared with those in the CsA group. Regarding the effects of apelin, our results indicate that apelin provides protection against CsA-induced tubular injury by activating nitric oxide and/or the NFATc1 pathway. Notably, we also found that CsA inhibits renal glucose reabsorption by reducing Na+-K+ ATPase expression and that apelin reverses reduced renal glucose reabsorption by CsA in tubular cells. CONCLUSIONS: Our study demonstrates the renoprotective effect of apelin against CsA-induced renal tubular toxicity and provides novel insights into the effects of CsA and apelin on renal tubular cells.

Decision Making by Young Transplant Surgeons Regarding Expanded-Criteria Donors With Acute Kidney Injury or Allocation Failure.

BACKGROUND: The utilization of expanded-criteria donors (ECDs) has increased to overcome donor shortages. Unfortunately, the discard rate has also increased, especially in ECDs with acute kidney injury (AKI). We evaluated the outcomes of kidney transplantation in ECDs and standard-criteria donors (SCDs) with and without AKI. METHODS: We reviewed the medical records of patients who underwent kidney transplantation. We used the AKI definition published by the Kidney Disease: Improving Global Outcomes group and reviewed the demographic characteristics of donors and recipients. We analyzed transplantation outcomes. RESULTS: Twenty-seven patients underwent kidney transplantation from ECDs with AKI (n = 6) or without AKI (n = 5) and SCDs with AKI (n = 6) or without AKI (n = 10). Initial creatinine and estimated glomerular filtration rate (eGFR) were not significantly different between the groups. The incidence of delayed graft function was highest in ECDs with AKI (n = 3; 36.4%), but this was not a significantly difference. There was no difference in the last creatinine and eGFR in ECDs with AKI (1.32 mg/dL, 58.7 mL/min/1.73 m(2)), ECDs without AKI (1.67 mg/dL, 44.2 mL/min/1.73 m(2)), SCDs with AKI (0.94 mg/dL, 81.5 mL/min/1.73 m(2)) and SCDs without AKI (0.97 mg/dL, 81.8 mL/min/1.73 m(2)). CONCLUSIONS: As the donor pool is extended to ECDs, young transplant surgeons may increasingly face decisions regarding ECDs with AKI or allocation failure. There is no consensus regarding discard criteria. However, if the donor showed initially normal creatinine levels or if dual-kidney transplantation can be performed, young transplant surgeons should not hesitate to use ECDs with AKI or allocation failure.

Gastrointestinal phytobezoars in childhood.

We reviewed 33 children under the age of 15 with gastrointestinal phytobezoars. Twenty were boys and 13 were girls. Nearly all patients were observed in late fall and winter. In 22 patients, symptoms developed following ingestion of several ripe or dried persimmons with seeds but none had a history of unripe persimmon ingestion. All patients but three underwent enterotomy, gastrotomy, or enterotomy combined with gastrotomy for bezoar removal. The remaining three had small bowel resection due to strangulation. There was a single location of the bezoar in 85% and multiple locations in 15% at operation. Emergency laparotomy was performed on 25 patients who had typical mechanical intestinal obstruction revealed the plain abdominal films. It is not surprising that persimmon is the most common cause of bezoar formation in Korea, because it is a favorite fruit among Koreans, either in hard, soft, or dried variety.

Preduodenal portal vein: a cause of prenatally diagnosed duodenal obstruction.

Preduodenal portal vein is a rare congenital anomaly that causes high intestinal obstruction. The authors report on a newborn who was diagnosed as having duodenal obstruction at 30 weeks' gestation. During surgery the patient was found to have duodenal obstruction caused by a preduodenal portal vein. Malrotation was an associated finding. Treatment consisted of Ladd's procedure and a diamond-shaped duodenoduodenostomy performed anterior to the portal vein.

Purulent umbilical drainage from infection of left umbilical artery associated with open umbilicoperitoneal communication.

This is a case report of a 20-day-old girl with persistent umbilical drainage due to infection of the left umbilical artery that ruptured at the base of the umbilicus and formed an open umbilicoperitoneal communication.

Ultrasound-guided water enema: an alternative method of nonoperative treatment for childhood intussusception.

Ultrasound-guided water enema (USWE) reduction was performed in 115 patients with intussusception, which was diagnosed by ultrasound between April 1988 and August 1992 at Keimyung University Dongsan Medical Center. The overall rate of successful reduction was 80.9%. The rate was 91.0% for patients with symptoms of < or = 24 hours' duration, and 61.1% for patients with symptoms of more than 24 hours' duration (P < .001). Six patients had recurrence during the study period (recurrence rate, 5.2%). There was no perforation or other complications during and after the water enema reduction. The authors conclude that (1) USWE reduction for childhood intussusception has a higher rate of successful reduction and a lower rate of recurrence than does barium enema and (2) USWE is safe and may be an alternative method in the nonoperative treatment of intussusception.

The ultrasonographic 'triangular cord' coupled with gallbladder images in the diagnostic prediction of biliary atresia from infantile intrahepatic cholestasis.

PURPOSE: The aim of this study was to evaluate the importance of the ultrasonographic "triangular cord" (TC) coupled with gallbladder images in the diagnostic prediction of biliary atresia (BA) from infantile intrahepatic cholestasis. METHODS: Seventy-nine infants with cholestatic jaundice underwent ultrasound examinations, focusing on the TC and gallbladder images. The TC was defined as visualization of a triangular or bandlike periportal echogenicity (3 mm or greater in thickness), which represents a cone-shaped fibrotic mass cranial to the portal vein in infants with BA. An abnormal gallbladder (nonvisualized or small) was thought to be more suggestive of BA than infantile intrahepatic cholestasis. RESULTS: Among 25 infants with BA, 21 showed TC, whereas 4 had no TC. Fifty-three of 54 infants with infantile intrahepatic cholestasis had no TC, showing a diagnostic accuracy of 94% with 84% sensitivity and 98% specificity. As for positive predictive value in the diagnosis of BA by the TC coupled with gallbladder images, it was 100% when a positive TC was coupled with an abnormal gallbladder and 88% when a positive TC was coupled with a normal gallbladder. It decreased to 25% when a negative TC was coupled with an abnormal gallbladder. CONCLUSIONS: The TC appears to be a very specific and definite ultrasonographic finding in the early diagnosis of BA. Positive TC regardless of gallbladder images is highly suggestive of BA, showing a 95% positive predictive value, but BA cannot be ruled out when negative TC is coupled with an abnormal gallbladder, requiring further diagnostic modalities such as liver needle biopsy or hepatobiliary scintigraphy.

'Triangular cord': a sonographic finding applicable in the diagnosis of biliary atresia.

Biliary atresia (BA) is characterized by luminal obstruction of the extrahepatic bile duct with fibrous remnants. The authors reviewed ultrasonographic examinations of the fibrous tissue in the bifurcation of the portal vein at the porta hepatis and identified the triangular- or tubular-shaped echogenic density, the so-called "triangular cord" (TC), in the vicinity of the portal vein on a transverse or longitudinal scan. In this prospective study, the authors investigated whether TC was useful in the noninvasive diagnosis of biliary atresia in 18 infants who had persistent neonatal jaundice. This was done by comparing the ultrasonographic examination with the histopathologic examination (HPE) of liver specimens obtained from a needle biopsy. The TC was identified in nine patients, all of whom were confirmed to have BA by HPE. The TC was not observed in the other nine patients, who had neonatal hepatitis (NH). The mean size of the TC was 13 mm (wide) x 6 mm (thick) (width range, 5 to 21 mm; thickness range, 4 to 12 mm). The diagnosis of BA was confirmed at the time of Kasai hepatoportojejunostomy in eight of the nine patients whose TC was noted by ultrasonography (US). The other patient was discharged because his parents refused the operation; he died of liver failure at 15 months of age. The nine patients with absent TC were treated medically for NH. Eight of them improved clinically. The other, diagnosed to have NH by needle and wedge liver biopsies, was reexamined 40 days after the initial examination because of worsening jaundice. A 18 x 12-mm TC was visualized ultrasonographically. Additionally, a percutaneous liver biopsy specimen showed BA with severe portal fibrosis and ductal proliferation. The patient underwent a Kasai hepatoportoenterostomy. On the basis of these results, the authors conclude that TC is a very specific ultrasonographic finding, representing the fibrous cone at the porta hepatis, and is a useful tool in the noninvasive diagnosis of BA. However, early exploration or close US follow-up is recommended for any patient suspected of having BA clinically, even if a liver biopsy confirms the NH.

Appendicoumbilical fistula as a sequela of perforated appendicitis.

This is the first report, we believe, of a 5-year-old boy who developed appendicoumbilical fistula as a sequela of perforated appendicitis. We discuss a proposed explanation of the mechanism in its formation.

Ectopic umbilical liver in conjunction with biliary atresia: uncommon association.

The case of a neonate with an ectopic liver in the umbilicus in conjunction with biliary atresia in the liver proper and an ectopic pancreas in the jejunum is reported. Following excision of the ectopic umbilical liver and Kasai type 1 hepatic portoenterostomy, bile fistula originating in the anterior inferior area of the right lobe of the liver was a complication, and it was successfully treated by construction of hepaticojejunostomy. No similar case has been reported in English language literature. It is of particular interest that the pathological features of the ectopic liver and the liver proper are quite similar.

Prepubic dermoid sinus: possible variant of dorsal urethral duplication (Stephens type 3).

The authors present the case of 4-month-old girl with a midline prepubic sinus extending from the skin overlying the pubis to the superior surface of the bladder, and continuing to the umbilicus via the median umbilical ligament. The distal portion of the exicised sinus was surrounded by concentric bundles of collagen and smooth muscle with minimal inflammatory infiltrates, which suggests a developmental origin. According to Stephens' classification, the sinus appears to be a variant of dorsal urethral duplication of Stephens type 3.

A new diagnostic approach to biliary atresia with emphasis on the ultrasonographic triangular cord sign: comparison of ultrasonography, hepatobiliary scintigraphy, and liver needle biopsy in the evaluation of infantile cholestasis.

BACKGROUND/PURPOSE: The authors evaluated prospectively the utility of ultrasonography, Tc-99m-DISIDA hepatobiliary scintigraphy, and liver needle biopsy in differentiating biliary atresia (BA) from intrahepatic cholestasis in 73 consecutive infants who had cholestasis. METHODS: Sixty three ultrasonographic examinations of 61 infants with 7.0-MHz transducer were carried out, focusing on the fibrous tissue at the porta hepatis. The authors defined the triangular cord (TC) as visualization of a triangular or tubular shaped echogenic density just cranial to the portal vein bifurcation on a transverse or longitudinal scan. RESULTS: Although 17 of 20 ultrasonographic examinations from infants who had BA denoted TC, 43 ultrasonographic examinations from infants with either neonatal hepatitis (NH) or other causes of cholestasis denoted no TC, showing a diagnostic accuracy of 95% with 85% sensitivity and 100% specificity. Investigation with Tc-99m-DISIDA hepatobiliary scintigraphy showed that 24 of 25 infants who had BA had no gut excretion, and 16 of 46 infants who had either NH or other causes of cholestasis had gut excretion, showing a diagnostic accuracy of 56% with 96% sensitivity and 35% specificity. Therefore, gut excretion of tracer excluded BA, but no gut excretion of tracer needed further investigations as liver needle biopsy. Forty-four liver needle biopsies were carried out in 19 infants who had BA and 24 infants who had either NH or other causes of cholestasis. Although 18 of 20 biopsy findings in infants who had BA were correctly interpreted as having BA, 23 of 24 biopsy results in infants who had either NH or other causes of cholestasis were correctly diagnosed, showing a diagnostic accuracy of 93% with 90% sensitivity and 96% specificity. CONCLUSIONS: Since the introduction of ultrasonographic TC sign in the diagnosis of BA by our institution, we have found that it seemed to be a simple, time-saving, highly reliable, and non-invasive tool in the diagnosis of BA from other causes of cholestasis. The authors propose a new diagnostic strategy in the evaluation of infantile cholestasis with emphasis on ultrasonographic TC sign as first priority of investigations. When the TC is visualized, prompt exploratory laparotomy is mandatory without further investigations. When the TC is not visualized, hepatobiliary scintigraphy is the next step. Excretion of tracer into the small bowel actually rules out BA. Liver needle biopsy is reserved only for the infants with no excretion of tracer. The authors believe that a correct decision regarding the need for surgery can be made in almost all cases with infantile cholestasis by this multidisciplinary approach.

Electron microscopic study of the liver with biliary atresia and neonatal hepatitis.

Eleven cases of biliary atresia (BA) and eight of neonatal hepatitis (NH) were studied, using transmission electron microscopy, to document their different ultrastructural characteristics and to elucidate the possible pathogenesis of biliary atresia. Among 30 consecutive liver biopsies obtained from 19 infants with BA or NH, 21 specimens composed (13 BA, 8 NH) were examined ultrastructurally. The electron microscopic features of NH (patients' age range, 35 to 60 days) were (1) giant hepatocytic transformation with scattered areas of dilated endoplasmic reticulum, indicative of intracytoplasmic degeneration, (2) frequent cytoplasmic biliary necrosis, and (3) relatively intact microvilli in most bile canaliculi, which contained some hepatocytic cytoplasmic fragments. These features strongly suggest that the main pathological process in NH is hepatocellular injury rather than bile duct damage. In contrast, all cases with BA (age range, 27 to 130 days) demonstrated (1) marked hepatocellular cholestasis associated with many lysosomes and myelin figures, (2) marked loss of bile canalicular microvilli, (3) degenerated bile ductular cells containing bile pigments, and (4) periductal inflammatory fibrosis. These features suggest that the main pathological process in BA involves the biliary system. A few viral inclusions were observed in two cases with BA, which suggests that viral infection is a potential cause. In two BA cases (aged 40 and 43 days at the time of first biopsy), the ultrastructural findings essentially were the same as those of NH, and follow-up biopsy specimens (at 48 and 94 days) showed findings consistent with BA. Such results support Landing's hypothesis that BA and NH are different manifestations of a single pathological process.

Environmental controls in reducing house dust mites and nasal symptoms in patients with allergic rhinitis.

A randomized comparison group pretest-posttest experimental design was used to quantitatively determine the effects of environmental control measures on patients with allergic rhinitis. Environmental controls included wrapping the mattress with a vinyl cover, washing the top bedding cover with 55 degrees C hot water every two weeks, removal of soft furniture, and wet cleaning of the bedroom floor every day. Thirty subjects were randomly assigned to experimental and control groups. The amount of house dust mites in dust samples collected from the bedroom floor, bedding and mattress, as well as the nasal symptoms of patients, were measured twice at one-month intervals. A significant decrease in house dust mites in dust samples and relief in patients' nasal symptoms were observed in the experimental group who had environmental controls.

Non-diabetic renal disease in patients with non-insulin dependent diabetes mellitus.

The diagnosis of diabetic nephropathy (DN) is almost always based on clinical grounds. The diagnosis is supported by a long history of diabetes, evidence of target organ damage and proteinuria preceding azotemia. The validity of this clinical approach is well established in insulin dependent diabetes mellitus but not in non-insulin dependent diabetes mellitus (NIDDM). It is thus important to determine which patients with NIDDM accompanied by non-diabetic renal disease (NDRD) should have a biopsy. However, factors clinically associated with NDRD in patients with NIDDM remain unclear. Therefore we reviewed clinical data, laboratory data and renal biopsies from 22 NIDDM patients who underwent renal biopsy between 1992 and 1998 in Wonju Christian Hospital. From this data, we identified important features that would discriminate between DN and NDRD. There were 8 women and 14 men. Age ranged from 33 to 68 (51.2 +/- 10.7) years. The duration of diabetes at biopsy ranged from 0 to 13 (4.2 +/- 4.2) years. Nephrotic syndrome was present in 13 patients. The patients with NDRD (n = 14) and DN (n = 8) had comparable 24-hour proteinuria, 24-hour albuminuria, creatinine clearance, serum creatinine, albumin, as well as incidences of neuropathy and hypertension. The significant factors that predict the NDRD included a short duration of the diabetes mellitus, the presence of dysmorphic red blood cells in urine, the absence of retinopathy and HbA1c below 9% (p < 0.05, respectively). NDRD included IgA nephropathy (n = 6), minimal change disease (n = 3), membranous nephropathy (n = 3), membranous lupus nephritis (n = 1) and acute interstitial nephritis (n = 1). Multiple logistic regression analysis revealed that the short duration of DM and the absence of retinopathy were factors significantly associated with NDRD. In summary, when there is a short duration of diabetes mellitus, or an absence of retinopathy seen in patients with NIDDM, then renal biopsy in diabetic patients aids in the detection of NDRD.

A case of membranoproliferative glomerulonephritis associated with a hydatidiform mole.

We treated a 54-year-old woman who was suffering from membranoproliferative glomerulonephritis associated with a complete type of hydatidiform mole. The renal manifestations were proteinuria and hematuria. A renal biopsy, performed before gynecologic management, disclosed focal and segmental subendothelial deposits with a proliferation of the mesangial cell and showed irregularly thickened capillary loops by light and electronmicroscoy. Genralized edema, proteinuria and hematuria were completely recovered by suction and curettage of the hydatidiform mole with prophylactic chemotherapy. The clinical manifestation of earlier presented 3 cases have been the nephrotic syndrome. The common feature of them was a complete remission of the nephropathy after the removal of the hydatidiform mole. The relationship between the hydatidiform mole and glomerulonephritis remains unresolved at present. But we concluded that the hydatidiform mole might be a cause of glomerulonephritis in this case.

Choroidal tuberculoma with membranous glomerulonephritis.

We report treatment of a 24-year-old man with membranous glomerulonephritis (MGN) who developed a solitary choroidal tuberculoma in association with miliary tuberculosis during steroid therapy. In June 1995, the patient had developed nephrotic syndrome. He had refused renal biopsy at that time. So we treated him with corticosteroids having assumed a diagnosis of minimal change nephrotic syndrome. After initial corticosteroids and diuretics therapy for 5 months, his generalized edema resolved but proteinuria (3 positive) continued, suggesting the presence of other forms of glomerulonephritis. Renal biopsy performed in January 1996. The patient was diagnosed as having MGN. The patient was closely observed over a period of 34 months and remained stable without steroid therapy. However at 34 months, generalized edema was again noted and steroid therapy at high dosage was initiated. After 5 months of steroid therapy, he developed miliary tuberculosis and a solitary choroidal mass. An antituberculosis chemotherapeutic regimen was started and after a further 5 months, all clinical symptoms and signs of the pulmonary lesion were resolved and a measurable shrinking of the choroidal mass was recorded.

Enantioselective determination of cetirizine in human urine by HPLC.

In order to study the simultaneous determination of (+)- and (-)-cetirizine in human urine we have developed a chiral separation method by HPLC. A chiral stationary phase of alpha1-acidglycoprotein, the AGP-CSP, was used to separate the enantiomers. The pH of the phosphate buffer, as well as the content of the organic modifier in the mobile phase, markedly affected the chromatographic separation of (+)- and (-)-cetirizine. A mobile phase of 10 mmol/l phosphate buffer (pH 7.0)-acetonitrile (95: 5, v/v) was used for the urine assays. Ultraviolet absorption was monitored at 230 nm and roxatidine was employed as the internal standard for quantification. (+)-Cetirizine, (-)-cetirizine and the internal standard were eluted at retention times of 12, 16, and 32 mins, respectively. The detection limit for cetirizine enantiomers was 400 ng/ml of urine. A pharmacokinetic study was conducted with the help of 5 healthy female volunteers who were administered with a single oral dose of racemic cetirizine (20 mg). The peak area ratios provided by the cetirizine enantiomers were linear (r>0.997) over a concentration range of 2.5-200 microg/ml. The peak of the excreted cetirizine enantiomers appeared in the urine sample during the period of 1-2 hrs following the administration of the oral dose. The excreted level of (+)-cetirizine was slightly higher than (-)-cetirizine but the difference was not statistically significant. However, this method appears to have applications for enantioselective pharmacokinetic studies of racemic drugs.

Ultrasonographic "triangular cord": the most definitive finding for noninvasive diagnosis of extrahepatic biliary atresia.

Early diagnosis of extrahepatic biliary atresia (EHBA) is very important for a successful bile drainage procedure. An urgent and extensive investigation is warranted to make a differential diagnosis of EHBA from other cholestatic disease, especially neonatal hepatitis (NH). The diagnosis may be made by laparotomy with cholangiogram and liver biopsy but these procedure are invasive. Because a cone-shaped fibrous tissue was always found at the porta hepatis during Kasai's procedure and that type of fibrous tissue has never been seen in other types of cholestatic jaundice, the authors have used ultrasonography (US) to detect fibrous remnants at the porta hepatis in infants clinically suspected of having EHBA and identified a triangular- or tubular-shaped echogenic density in the bifurcation of the portal vein at the porta hepatis in EHBA and called it an ultrasonographic "triangular cord (TC)". The authors determined that the presence of TC denoted the EHBA. On the other hand, nonvisualization of TC was interpreted as consistent with NH. In the present study, the authors reviewed ultrasonographic examination and hepatobiliary scintigraphy in a series of 41 infants suspected of having EHBA or NH. The TC was identified in thirteen infants. In twelve of thirteen infants with TC found by US, the diagnosis of EHBA was confirmed at the time of Kasai's Roux-en-Y hepatoportojejunostomy operation. The remaining one died at 15 months of age without having treatment. TC was not visualized in 28 infants. Twenty-seven of 28 infants with absent TC improved clinically through medical treatment for NH. The other, diagnosed to have NH by needle and wedge liver biopsies, eventually showed a TC on follow-up US examination performed 40 days after the initial examinations. Moreover, follow-up percutaneous liver biopsy specimen showed typical findings of biliary atresia with bile duct proliferation and portal fibrosis. The patient underwent a Kasai hepatoportoenterostomy. On review of the hepatobiliary scintigraphy, all 13 infants with TC had no intestinal excretion of isotope. Thirteen of 28 infants (46%) without TC also had no intestinal excretion of isotope in the 24hour follow-up but all of them were confirmed to have NH by percutaneous liver biopsy and their subsequent clinical course confirmed NH with the detection of bile in their stool except one. On the basis of these results, the authors conclude that ultrasonographic TC is a very specific finding representing the fibrous cone at the porta hepatis and is a quick, simple, and definitive tool in the noninvasive diagnosis of EHBA. If TC is visualized, no further studies are necessary and exploratory-laparotomy can be done. If TC is not visualized, hepatobiliary scintigraphy is recommended to demonstrate bile duct patency. Percutaneous liver biopsy is only required if neither TC nor intestinal excretion of isotope is seen. However, early exploration or close US follow-up study is recommended in any patient suspected of having EHBA clinically, even if liver biopsy confirms the presence of NH.

Do dialysis patients need extra folate supplementation?

To assess folate status and to evaluate the need for conventional folate supplementation in patients on dialysis, we measured serum folate, vitamin B12, and red cell folate concentrations by radioimmunoassay. Thirty-four continuous ambulatory peritoneal dialysis (CAPD) patients and 60 hemodialysis (HD) patients who had not been supplemented with folate were enrolled. Serum folate levels (5.8 +/- 3.6 ng/mL vs 2.0 +/- 1.1 ng/mL, p < 0.001) and vitamin B12 levels (831.4 +/- 416.9 pg/mL vs 513.9 +/- 213.3 pg/mL, p < 0.001) were significantly higher in CAPD patients than HD patients. The red cell folate levels (849.7 +/- 489.4 ng/mL vs 491.0 +/- 253.2 ng/mL, p < 0.001) were also significantly higher in CAPD patients. The incidences of folate deficiency in CAPD and HD patients were overestimated using the cut-off value for serum folate concentration (3.0% vs 71.7%, respectively), but the incidence of true folate deficiency was lower using the cut-off value for red cell folate level (0.0% vs 10.0%, respectively). In conclusion, the true incidence of folate deficiency in stable CAPD and HD patients is surprisingly low, even in patients who may not be taking folate supplements. The need for conventional folate supplementation in patients with end-stage renal disease on dialysis must therefore be re-evaluated. Before the decision is made to use folate supplementation, measurement of red cell folate is essential to assess of folate reserves of the patients on dialysis.