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PubMed2005

Enteric hyperoxaluria, nephrolithiasis, and oxalate nephropathy: potentially serious and unappreciated complications of Roux-en-Y gastric bypass.

BACKGROUND: Neither the presence nor prevalence of enteric hyperoxaluria has been recognized after Roux-en-Y gastric bypass (RYGBP). We have noted a high rate of oxalate nephrolithiasis and even 2 patients with oxalate nephropathy in this patient population postoperatively. Our aim was to determine the frequency of the occurrence and effects of enteric hyperoxaluria after RYGBP. METHODS: Retrospective review of all patients at our institution diagnosed with calcium oxalate nephrolithiasis or oxalate nephropathy after standard (n = 14) or distal (n = 9) RYGBP. The mean postoperative follow-up was 55 months. RESULTS: A total of 23 patients (14 men and 9 women; mean age 45 years; mean preoperative body mass index 55 kg/m(2)) developed enteric hyperoxaluria after RYGBP, defined by the presence of oxalate nephropathy (n = 2) or calcium oxalate nephrolithiasis (n = 21) and increased 24-hour excretion of urinary oxalate and/or calcium oxalate supersaturation. Enteric hyperoxaluria was recognized after a mean weight loss of 46 kg at 29 months (range 2-85) after RYGBP. Two patients developed renal failure and required chronic hemodialysis. Of the 21 patients with nephrolithiasis, 14 had no history of nephrolithiasis preoperatively, and 19 of 21 required lithotripsy or other intervention. Of the 23 patients, 20 tested had increased oxalate excretion, and 14 of 15 tested had high urine calcium oxalate supersaturation. CONCLUSION: Enteric hyperoxaluria, nephrolithiasis, and oxalate nephropathy must be considered with the other risks of RYGBP. Efforts should be made to identify factors that predispose patients to developing hyperoxaluria.

Adult↗
PubMed1992

Plasma and urine glycolate assays for differentiating the hyperoxaluria syndromes.

To differentiate hyperoxaluria syndromes we measured plasma and urine glycolate by a novel high performance liquid chromatographic procedure. Mean glycolate level was 7.9 +/- 2.4 mumol./l. in plasma and 422 +/- 137 mumol./24 hours in urine from 19 control subjects. Renal clearance was about 50% the glomerular filtration rate irrespective of the underlying disease. There was close correlation between glycolate and oxalate in plasma. Plasma glycolate was normal in all but 8 patients who had primary hyperoxaluria 1. Plasma assay detected the disease more efficiently than urine assay. Pyridoxine decreased oxalate biosynthesis in 2 of the 4 patients treated with it and glycolate assay confirmed this behavior. Glycolate excretion was significantly high in 3 of 8 patients of primary hyperoxaluria 1 patients. Idiopathic stone formers had mild increases in glycolate excretion but this was not related with oxalate excretion. Glycolate levels were normal in 5 patients with enteric hyperoxaluria. We conclude that glycolate assay is essential for identifying patients with primary hyperoxaluria 1 and may represent a valuable tool for differentiating hyperoxaluria.

Adolescent↗
PubMed1991

Diet and hyperoxaluria in the syndrome of idiopathic calcium oxalate urolithiasis.

Hyperoxaluria is an important risk factor in patients who form calcium oxalate stones within the urinary tract. It occurs in patients with primary hyperoxaluria, enteric hyperoxaluria, and the syndrome of idiopathic calcium oxalate urolithiasis. In the latter condition, the specific causes of the hyperoxaluria are not well defined. Diet and the availability of calcium and oxalate from the diet within the intestine are important factors in the hyperoxaluria that is present in some of these patients with idiopathic calcium oxalate urolithiasis. Other abnormalities in endogenous metabolism or transport of oxalate may play a role in the hyperoxaluria in some of these patients.

Calcium↗
PubMed2001

Protective role of enalapril for chronic tubulointerstitial lesions of hyperoxaluria.

PURPOSE: Hyperoxaluria is a recognized cause of tubulointerstitial lesions and it may contribute to chronic renal failure. In previous studies we demonstrated that enalapril was effective against the progression of tubulointerstitial lesions in a 4-week hyperoxaluria rat model. We evaluated whether the action of enalapril on the tubulointerstitial lesions produced by hyperoxaluria persisted for a long period. MATERIALS AND METHODS: Two-month-old male Sprague-Dawley rats were divided into 4 groups of 12 each, including 1--control animals given tap water, 2--animals with hyperoxaluria, 3--animals with hyperoxaluria plus enalapril, 4--animals with enalapril. Hyperoxaluria in groups 2 and 3 rats was induced by administering 1% ethylene glycol, a precursor for oxalates, in the tap water continuously throughout the whole study. Meanwhile, groups 3 and 4 received 20 mg./l. enalapril in the drinking water. At the end of the study renal tubulointerstitial lesions were evaluated by immunostaining using monoclonal antibodies against macrophage infiltrates (ED1), tubulointerstitial alpha-smooth muscle actin and transforming growth factor-beta1. The lesions were quantified by semiquantitative scores. Creatinine clearance and urinary albumin excretion were also determined. RESULTS: There was no difference in urine oxalate excretion in groups 2 and 3. Group 3 rats treated with enalapril showed fewer tubulointerstitial lesions than nontreated group 2 rats, as indicated by the mean scores plus or minus standard error of mean for inflammatory infiltrate (2.16 +/- 0.2 versus 0.83 +/- 0.16), tubular atrophy (2 +/- 0.27 versus 0.66 +/- 0.14), interstitial fibrosis (2.5 +/- 0.15 versus 0.5 +/- 0.1), glomerular ED1 (1.75 +/- 0.25 versus 0.16 +/- 0.11), interstitial ED1 (2.33 +/- 0.18 versus 0.58 +/- 0.10) tubular transforming growth factor-beta1 (2.09 +/- 0.08 versus 0.91 +/- 0.14), interstitial transforming growth factor-beta 1 (2.33 +/- 0.22 versus 0.66 +/- 0.12), tubulointerstitial alpha-smooth muscle actin (2.91 +/- 0.22 versus 0.83 +/- 0.16), lower urinary albumin excretion (35.5 +/- 2.7 mg. daily versus 10.9 +/- 1) and higher creatinine clearance (2.29 +/- 0.04 ml. per minute versus 2.54 +/- 0.03, all p <0.05). CONCLUSIONS: Based on our results we believe that enalapril would provide a beneficial effect against chronic tubulointerstitial lesions caused by oxalates.

Angiotensin-Converting Enzyme Inhibitors↗
PubMedDate not supplied

Unusual morphology of calcium oxalate calculi in primary hyperoxaluria.

Primary hyperoxaluria (PH) is a severe inherited disease induced by an enzymatic deficiency responsible for high endogenous production of oxalate. Oxalate ions are excreted by the kidney where they can form an insoluble salt with calcium ions, thus inducing urinary stones, crystal deposition in the tubular lumen and renal parenchyma leading to nephrocalcinosis and renal failure. Eighty-seven calculi from 63 PH patients with primary hyperoxaluria were analyzed and compared to 24,130 calculi from unselected consecutive stone formers referred to our laboratory between January 1977 and December 1996. All stones were analyzed according to a protocol including morphological examination of both surface and cross-section, and sequential infrared identification of the crystalline phases. A typical aspect of both surface and section corresponding to morphological type Ic according to our proposed classification (Daudon et al. Scanning Microsc 1993, 7:1081-1106) was observed in all patients but two whereas only two type Ic stones were observed among patients without primary hyperoxaluria. The latter two patients suffered from severe inflammatory bowel disease and developed heavy hyperoxaluria following extensive ileal resection. We conclude that evidence of type Ic morphology is a simple, cheap and fast tool to detect diseases with heavy hyperoxaluria such as primary hyperoxaluria.

Adult↗
PubMed1983

The effect of clindamycin on the intestinal flora in patients with enteric hyperoxaluria.

Enteric hyperoxaluria is due to increased absorption of oxalate, especially in the colon. However, this mechanism is not fully understood. Little is also known about the composition of the intestinal flora in these patients. Eleven patients with hyperoxaluria (greater than 0.45 mmol/24 h) after jejunoileal bypass were therefore studied under surgical ward conditions for 5 days. The patients were maintained on a constant diet. During days 3, 4, and 5 clindamycin (Dalacina), 1.8 g/24 h, was given parenterally in three divided doses. All patients had hyperoxaluria, with a mean oxalate absorption of 0.94 +/- 0.09 mmol/24 h (+/- SEM). No significant disturbances in the colonic microflora were found. The degree of hyperoxaluria did not change during clindamycin administration, in spite of a significant decrease in the number of anaerobic bacteria. Our patients with enteric hyperoxaluria seem to have a normal colonic microflora. The degree of hyperoxaluria did not seem to be related to changes in the intestinal anaerobic flora.

Adult↗
PubMed1986

Absorptive hyperoxaluria: a new clinical entity--successful treatment with hydrochlorothiazide.

This report describes studies performed over an 11 year period in a 13 year old girl with hyperoxaluria and calcium oxalate nephrolithiasis who did not have primary hyperoxaluria or any of the recognized causes of secondary hyperoxaluria. The patient also had increased urinary excretion of calcium and magnesium and hyperabsorption of dietary calcium and magnesium. It is suggested that the hyperoxaluria resulted from hyperabsorption of dietary oxalate secondary to hyperabsorption of dietary calcium. Hyperabsorption of dietary magnesium and increased urinary magnesium excretion have not previously been reported in this context. Stone formation ceased and urinary oxalate excretion gradually fell to normal during long term thiazide therapy but hyperoxaluria recurred when orthophosphate therapy was substituted for the hydrochlorothiazide. This is the first report of normalization of urine oxalate excretion during thiazide therapy in a patient with frank hyperoxaluria.

Adolescent↗
PubMed2000

Renal tubular apoptosis after complete ureteral obstruction in the presence of hyperoxaluria.

Hyperoxaluria is a well-known cause of renal stone disease and in vitro studies have shown that oxalate crystals have a stimulatory effect on apoptosis of renal tubular epithelial cells. Total and partial ureteral obstruction also have an accelerating effect on apoptosis of renal tubular epithelial cells. The aim of the present study was to investigate the apoptotic effect of unilateral ureteral obstruction in the presence of hyperoxaluria on the rat kidney. Twenty-eight male Wistar rats were divided into four groups, with seven rats in each. The groups were named G1 (control), G2 (hyperoxaluric), G3 (obstructive) and G4 (hyperoxaluric + obstructive). G2 and G4 rats were given 1% ethylene glycol (a precursor for oxalates) in their drinking water. G1 and G2 rats underwent sham operation, while left proximal ureteral ligation with a 5-zero silk suture was performed on G3 and G4 animals. The rats were sacrificed 2 weeks after the operation; left nephrectomy was then performed. We searched for the apoptotic cells by direct immuno-peroxidase detection of digoxigenin-labeled genomic DNA. The mean +/- SD values of the apoptotic cell count was 0.86+/-0.90 in G1 and 4.33+/-3.81 in G2. The values for G3 and G4 were 30.17+/-16.85 and 302.67+/-184.45, respectively. We found a statistically significant difference between all groups (P < 0.001). When compared with the control group (G1), the mean apoptotic cell count was fivefold that of G2 and 35- and 351-fold those of G3 and G4, respectively. Our study demonstrated that hyperoxaluria with complete ureteral obstruction induces an excessive level of apoptosis, which is responsible for renal damage, and that ureteral obstruction is a more important factor for apoptosis than hyperoxaluria. Considering these data, we also believe that research studies for medical preventive measures must be considered for patients with ureteral obstruction and/or hyperoxaluria.

Animals↗
PubMed1998

Absence of Oxalobacter formigenes in cystic fibrosis patients: a risk factor for hyperoxaluria.

BACKGROUND: Patients with cystic fibrosis have an increased risk of hyperoxaluria, and of subsequent nephrocalcinosis and calcium-oxalate urolithiasis. Oxalate homoeostasis is controlled, in part, by the intestinal bacterium, Oxalobacter formigenes. The loss of this bacterium from the gut flora is associated with an increased risk of hyperoxaluria and calcium-oxalate urolithiasis. We investigated whether the absence of O. formigenes and the presence of hyperoxaluria are correlated in cystic fibrosis (CF) patients. METHODS: Stool specimens from 43 patients with CF aged 3-9 years and from 21 similarly aged healthy volunteers were examined for O. formigenes by culture and DNA analysis. At the same time, 24 h urine samples were collected and analysed for oxalate and other factors that promote or inhibit stone formation. FINDINGS: 15 (71%) of 21 healthy volunteers but only seven (16%) of 43 CF patients were colonised with O. formigenes. Detection of O. formigenes in six of these seven patients required DNA-based identification, suggesting low numbers of colony-forming units, and the CF patient with normal numbers of O. formigenes was the only one of the 43 patients who had not been treated with antibiotics. All seven CF patients colonised with O. formigenes had normal urinary oxalate levels, but 19 (53%) of 36 patients not colonised with O. formigenes were hyperoxaluric, with the most severe hyperoxaluria occurring in young patients. INTERPRETATION: Absence of O. formigenes from the intestinal tract of CF patients appears to lead to increased absorption of oxalate, thereby increasing the risk of hyperoxaluria and its complications (eg, nephrocalcinosis, urolithiasis). Prolonged widespread use of antibiotics, and alterations of the gastrointestinal tract that occur in CF, may induce a permanent decolonisation in CF patients.

Adolescent↗
PubMed2006

A de novo mutation in the AGXT gene causing primary hyperoxaluria type 1.

Primary hyperoxaluria type 1 is caused by mutations in the alanine-glyoxylate aminotransferase (AGXT) gene. In cases in which no mutation was identified, linkage analysis can be used to confirm or exclude the diagnosis in other siblings. We present a family in which a sibling of the index case predicted to have primary hyperoxaluria type 1 by means of linkage analysis failed to show hyperoxaluria during the following 7 years, putting the diagnosis into question. Whole-gene sequence analysis identified 2 causative mutations in the index case, of which only 1, c.646A (Gly216Arg), was inherited. The other sequence change, c.33_34insC, was a de novo mutation occurring on the paternal allele. This particular mutation is a relatively common cause of primary hyperoxaluria type 1. It occurs in a run of 8 cytosines and therefore potentially is susceptible to polymerase slippage. This case illustrates 2 important points. First, biochemical confirmation of a genetic diagnosis should always be made in siblings diagnosed by using genetic tests. Second, de novo mutations should be considered as a potential, albeit rare, cause of primary hyperoxaluria type 1.

Child, Preschool↗
PubMed1999

[Iterative fractures in type I primary hyperoxaluria. Report of 2 cases].

PURPOSE OF THE STUDY: Type I primary hyperoxaluria is a rare autosomal recessive disease linked to a deficit in an hepatic enzyme. The purpose of this study was to analyze orthopedics problems caused by type I primary hyperoxaluria before and after liver and kidney transplantation. MATERIAL AND METHODS: Two cases of children carrying this type I primary hyperoxaluria followed up after liver kidney transplantation are presented and compared to last publications. RESULTS: Combined transplantation progressively corrected osseous lesions and aspect of the stroma. However it did not provide protection against fractures particularly for femoral neck fractures. DISCUSSION: In type I hyperoxaluria overproduction of calcium oxalate causes its accumulation in the whole organism and particularly in bone. Osseous fragility favors pathological fractures. Only combined liverkidney transplantation can save and cure these children. Frequency of this fracture after transplantation indicates preventive plating at first pain, possibly at the same time as transplantation. Kidney transplant failure puts the patient in a "congealed" clinical state where the bone is very rich in oxalate and where the hemodialysis does not eliminate oxalate salts. CONCLUSION: Type I primary hyperoxaluria is a very rare disease. Fractures are very common even after liver and kidney transplantation and especialy femoral neck fractures. We think that preventive plating must be done at first pain. We do not have any explanation for bony weakness after liver-kidney transplantation.

Child↗
PubMed2006

Hyperoxaluria in women with vulvar vestibulitis syndrome.

OBJECTIVE: To determine whether evaluation and treatment of hyperoxaluria in vulvar vestibulitis syndrome (VVS) is justified. STUDY DESIGN: Forty women (mean age, 24.5 years; range, 18-35) diagnosed with VVS at a sex therapy clinic participated. Diagnosis of VVS relied upon Friedrich's criteria: (1) severe vulvar vestibular pain upon touch or attempted vaginal entry, (2) tenderness to pressure localized within the vulvar vestibule, and (3) physical findings confined to vulvar erythema of various degrees. Oxalate was measured in 24-hour urine samples. Women with hyperoxaluria (urine oxalate >50 mg/24 h) were placed on a low-oxalate diet and oral calcium citrate as single therapy and reevaluated 3 months later. RESULTS: Hyperoxaluria was diagnosed in 7 women (17.5%), of whom 1 demonstrated an objective improvement and could have pain-free vaginal intercourse following treatment, yielding a 2.5% benefit from the evaluation and treatment of hyperoxaluria. CONCLUSION: There is no justification for evaluation and treatment of hyperoxaluria in women with VVS due to its low yield and economic burden.

Adolescent↗
PubMed1996

[Hyperoxaluria and renal calculi].

Urolithiasis is one of the most frequent causes of morbidity in developed countries and its incidence is close to 5%. In our experience, 67.4% of urinary stones contain calcium oxalate as the main component, and hyperoxaluria plays an important role in the pathophysiology of this type of stone. The mechanisms responsible for the increment in urinary excretion of oxalate could involve oxalic acid synthesis. This increase could be due either to an increment of its endogenous formation or to an exogenous load of its precursors. Furthermore, an increased intestinal oxalate absorption is a frequent cause of hyperoxaluria and urolithiasis. Ingestion of oxalate rich foods, imbalance in the supply of other nutrients that influence oxalic acid absorption and GI disorders with malabsorption and/or decreased degradation of intraluminal oxalate can increase intestinal oxalate transport and cause hyperoxaluria. In this article we review the physiological mechanisms that control the oxalate pool: endogenous synthesis, exogenous supply, intestinal absorption and renal excretion of oxalic acid. We analyze the causes and the pathophysiological mechanisms that increase urinary oxalate excretion. We describe a protocol for the biochemical study of patients with hyperoxaluria and the therapeutic measures to reduce urinary oxalate are reviewed. Finally, possible research that may provide further insight into oxalate metabolism in patients with hyperoxaluria are discussed.

Aluminum↗
PubMed1977

Importance of the colon in enteric hyperoxaluria.

To investigate the role of the colon in increased oxalate absorption, we measured urinary oxalate and fecal fat excretion in 26 patients with gastrointestinal disease. Eight patients with steatorrhea of various causes (Crohn's disease [two], chronic pancreatitis [four], jejunoileal bypass [one] and extrahepatic biliary obstruction [one]) had hyperoxaluria (greater than 45 mg per 24 hours). All these patients had intact colons. In contrast, none of five patients with ileostomies and steatorrhea secondary to ileal resection had hyperoxaluria. Absorption of 14C-oxalate was increased in three patients with steatorrhea and intact colons but not in three patients with steatorrhea and an ileostomy. Thus, the colon is both the site of and required for increased oxalate absorption in enteric hyperoxaluria. The lack of a direct relation between fecal fat excretion and urinary oxalate excretion in the patients with hyperoxaluria and steatorrhea suggests that steatorrhea, although important, is not the only determinant in the pathogenesis of hyperoxaluria.

Celiac Disease↗
PubMed1985

Response to a physiologic dose of pyridoxine in type I primary hyperoxaluria.

We measured urinary oxalate and glycolate excretion before and during pyridoxine administration (2 to 200 mg per day) in four patients with primary hyperoxaluria. In two patients with type I primary hyperoxaluria, urinary oxalate and glycolate excretion fell markedly in response to a physiologic dose of pyridoxine of 2 mg per day and became completely normal when the dose was increased to 25 mg per day. In the other two patients, who had a different type of primary hyperoxaluria (normal urinary glycolate excretion), there was no response to 2 mg of pyridoxine per day. In one of these patients, doses of 25 and 50 mg per day were also ineffective, but a moderate reduction in oxalate excretion took place with 200 mg per day; in the other patient there was a moderate reduction in oxalate excretion with 25 mg of pyridoxine per day. Our findings suggest that the degree of hyperoxaluria in this disorder may be only slight or moderate if the patient has been ingesting a pyridoxine-rich diet or multivitamin tablets containing small amounts of pyridoxine. Our results also suggest that smaller doses of pyridoxine than those heretofore employed should be tried in patients with primary hyperoxaluria.

Child↗
PubMed1982

[Incidence of hyperoxaluria in idiopathic calcium nephrolithiasis].

Urinary excretion rate of oxalate was measured in 79 patients with idiopathic calcium (Ca) nephrolithiasis and the results were compared with those obtained in 28 healthy volunteers. The group of stone formers consisted of 20 patients with idiopathic hypercalciuria (IHC) of the absorptive type, 23 patients with IHC of the renal type, 11 patients with hypercalciuria secondary to dietary factors, 1 patient with hyperuricosuria (as an isolated finding) and 24 patients without hypercalciuria nor hyperuricosuria. Classification was based upon the urinary excretion rate of uric acid, as well as that of calcium measured under 3 different dietary conditions (i.e. free diet, free diet supplemented with 3 g Ca/day for 3 days, and diet free of dairy products for 5 days). On a free diet, normal values of oxaluria ranged from 125 to 435 mumol/24 h; an elevated value was observed in 11 (14%) patients, 5 of whom belonged to the subgroup without hypercalciuria nor hyperuricosuria. On a low Ca diet, mild hyperoxaluria occurred in 3 controls and in 19 patients, the tendency to develop hyperoxaluria being particularly marked in the subgroup with absorptive-IHC. Moreover, there was a positive correlation between oxaluria on a low Ca diet and the estimated degree of intestinal absorption of Ca. This study confirms the finding that on a free diet, the incidence of mild hyperoxaluria amongst idiopathic stone formers is rather low. It shows, however, that a significant percentage of patients classically referred to as "without metabolic disorder" have in fact slight hyperoxaluria, an observation with a potential therapeutic impact. Finally, it shows that on a low Ca diet, patients with absorptive-IHC are particularly prone to develop hyperoxaluria: the latter observation renders questionable the relevance of a low Ca diet for patients with absorptive IHC, unless their intake of oxalate is simultaneously reduced.

Adolescent↗
PubMed1990

Ocular findings in primary hyperoxaluria.

Primary hyperoxaluria (primary oxalosis) is a rare autosomal recessive inborn error of glyoxylate metabolism that causes widespread calcium oxalate crystal deposition in diverse tissues. Because others have reported only occasional ocular involvement, we reviewed the ophthalmologic findings in our 24 patients with primary hyperoxaluria to document its funduscopic variability and to determine its visual prognosis and its possible systemic significance. Eight (30%) of our 24 patients with primary hyperoxaluria exhibited a bilaterally symmetrical retinopathy. The abnormalities were predominantly confined to the posterior pole and ranged from many small (100- to 200-microns) subretinal black ringlets to single large (2- to 3-disc diameter) geographic lesions. In 3 of the 8 patients with oxalate retinopathy, diffuse optic disc pallor was evident. Five patients with both normal-appearing optic discs and oxalate retinopathy had relatively good visual acuities. The maculopathy of primary hyperoxaluria caused mild visual impairment while optic nerve dysfunction associated with this disease appeared to be much visually debilitating. Also, the presence of oxalate maculopathy was associated with a more severe systemic course for the disease.

Acute Kidney Injury↗
PubMed1988

Further studies on the activity and subcellular distribution of alanine:glyoxylate aminotransferase in the livers of patients with primary hyperoxaluria type 1.

1. The activity of alanine:glyoxylate aminotransferase (AGT; EC 2.6.1.44) has been measured in the unfractionated livers of 20 patients with primary hyperoxaluria type 1 (PH1), three patients with other forms of primary hyperoxaluria and one PH1 heterozygote. The subcellular distribution of AGT activity was examined in four of the PH1 livers and in the liver of the PH1 heterozygote. 2. The mean AGT activity in the unfractionated PH1 livers was 12.6% of the mean control value. The activities of other aminotransferases and the peroxisomal marker enzymes were normal. When corrected for cross-over from glutamate:glyoxylate aminotransferase (GGT; EC 2.6.1.4), the mean AGT activity in the PH1 livers was reduced to 3.3% of the control values. 3. The livers from a patient with primary hyperoxaluria type 2 (D-glycerate dehydrogenase deficiency) and one with an undefined form of primary hyperoxaluria (possibly oxalate hyperabsorption) had normal AGT levels. The livers of a very mild PH1-type variant and a PH1 heterozygote had intermediate levels of AGT activity. 4. Subcellular fractionation of four PH1 livers by sucrose gradient isopycnic centrifugation demonstrated a complete absence of peroxisomal AGT activity. The subcellular distribution of the residual AGT activity was very similar to that of GGT activity (i.e. mainly cytosolic with a small amount mitochondrial). There were no alterations in the subcellular distributions of any of the peroxisomal marker enzymes. The subcellular distribution of AGT activity in the PH1 heterozygote liver was similar to that of the control (i.e. mainly peroxisomal).

Adolescent↗