Oxalate nephropathy in an elderly patient with newly diagnosed celiac disease - a case report.

Oxalate nephropathy, due to secondary hyperoxaluria has widely been described in gastrointestinal diseases. However, reports of oxalate nephropathy in newly diagnosed celiac disease are rare. A 72-year-old Caucasian male presented to the hospital with abdominal discomfort and acute renal insufficiency with a creatinine of 290 µmol/L. The clinical course, laboratory results and urinalysis were suspect for tubular injury. Renal biopsy showed calcium oxalate depositions. Elevated plasma and urine oxalate levels established the diagnosis oxalate nephropathy. The abdominal complaints with steatorrhea and positive anti-tissue transglutaminase antibodies were diagnosed as celiac disease, which was confirmed after duodenal biopsies. Treatment with prednisone, and gluten-free, low oxalate and normal calcium diet, lowered the plasma oxalate levels and improved his renal function. Decreased absorption of free fatty acids can lead to increased free oxalate in the colon due to the binding of free fatty acids to calcium, preventing the formation of the less absorbable calcium oxalate in the colon. Oxalate dispositions in the kidney can lead to acute tubular injury and chronic renal insufficiency. Celiac disease is therefore one of the intestinal diseases that can lead to hyperoxaluria and oxalate nephropathy.

Pancreatic insufficiency as a complication of type 1 diabetes causing enteric hyperoxaluria in a transplant kidney.

A kidney transplant recipient with a medical history of type 1 diabetes mellitus (T1DM) presents to the clinic with an acute kidney injury (AKI) and diarrhoea. Kidney biopsy found deposition of focal oxalate crystals, and further investigation revealed a raised 24-hour urinary oxalate and reduced faecal elastase. Therefore, we present a case of acute oxalate nephropathy (AON) secondary to enteric hyperoxaluria as a result of pancreatic insufficiency caused by T1DM. T1DM is a common cause of end-stage renal failure and exocrine pancreatic insufficiency. Therefore, AON secondary to enteric hyperoxaluria should be considered in patients with a transplant AKI. Earlier testing of 24-hour urinary oxalate and faecal elastase could generate diagnosis before biopsy results and allow commencement of pancreatic replacement therapy earlier to avoid permanent loss of kidney function.

Oxalate crystal-related acute renal injury caused by orlistat: A case report. / å¥¥åˆ©å¸ä»–è‡´è‰é ¸ç›ç»“æ™¶ç›¸å ³æ€¥æ€§è‚¾æŸä¼¤1例.

We reported a case of oxalate crystal-related acute kidney injury caused by orlistat. The patient was admitted for nephrotic syndrome and acute kidney injury. The pathomorphological assessment of renal biopsy showed intratubular oxalate crystals. The patient reported that she had taken orlistat regularly to loss weight for more than a year. This patient had a habit of drinking vegetable soup and strong herbal tea daily. Orlistat, an intestinal lipase inhibitor, may cause secondary hyperoxaluria, that is, intestinal hyperoxaluria. Dietary habits could be a common precipitating factor for orlistat-relevant hyperoxaluria. It was comprehensively considered to be oxalate crystal-related acute renal injury, and the patient's renal function recovered gradually after drug withdrawal. Clinicians should pay attention to screening drug-related acute kidney injury including orlistat when observing patients with unexplained acute kidney injury, and renal biopsy should be performed if necessary. It is also important to warn people who take the orlistat for weight loss about the side effects of this drug so as to adjust the eating habits.

Secondary oxalate nephropathy in a patient with exocrine pancreatic insufficiency successfully treated, with complete kidney recovery.

INTRODUCTION: Oxalate nephropathy is a relatively rare and under-recognized condition that commonly presents as acute kidney injury (AKI) and often leads to end-stage renal disease. Complete recovery of kidney function is extremely rare even when treatment is instituted early on. CASE PRESENTATION: We present the case of a 68-year-old man with known type 2 diabetes mellitus and an asymptomatic unrecognized exocrine pancreatic insufficiency, who was admitted due to dialysis-dependent AKI. Kidney biopsy revealed oxalate nephropathy. A wide diagnostic assessment and a multi-factorial treatment plan that included a change of diet, therapy for exocrine pancreatic insufficiency and fat malabsorption, sodium bicarbonate and potassium citrate, calcium supplements with meals, and methylprednisolone, resulted in complete recovery of kidney function. CONCLUSION: It is important for physicians to be aware of oxalate nephropathy in cases of prolonged AKI. After confirmation of diagnosis, a wide diagnostic approach is imperative to identify all the causes that have led to oxalosis. A multi-factorial therapeutic approach can lead to complete kidney recovery.

Unusual cause of irreversible acute kidney injury postgastrectomy.

A 56-year-old male was diagnosed to have carcinoma stomach following evaluation of lack of appetite and weight loss. He underwent neoadjuvant chemotherapy and gastrectomy. Following surgery he developed progressive renal failure. A renal biopsy led to the diagnosis of oxalate nephropathy. Despite treatment his renal functions never recovered. Oxalate nephropathy is an underappreciated cause of renal failure postgastrectomy. It can cause irreversible renal failure unless detected and treated early.

Collapsing Focal Segmental Glomerulosclerosis and Acute Oxalate Nephropathy in a Patient With COVID-19: A Double Whammy.

As COVID-19 (coronavirus disease 2019) spreads across the world multiple therapeutic interventions have been tried to reduce morbidity and mortality. We describe a case of collapsing focal sclerosing glomerulosclerosis (FSGS) and acute oxalate nephropathy in a patient treated with high-dose intravenous vitamin C for severe COVID-19 infection. Collapsing FSGS has been described in patients with COVID-19 infection associated with APOL-1; however, this case had collapsing FSGS developing in low-risk heterozygous APOL-1 variant, and we postulate that the intensity of the COVID-19 cytokine storm overwhelmed the protective state of APOL-1 heterozygosity. This case illustrates the importance of assessing the risk and benefit of planned therapeutic interventions on a case-by-case basis especially when there are still so many unknowns in the management of COVID-19 infection. Strong consideration should be given for performing a renal biopsy in patients who develop multifactorial acute kidney injury.

Calcium oxalate crystal deposition in the kidney: identification, causes and consequences.

Calcium oxalate (CaOx) crystal deposition within the tubules is often a perplexing finding on renal biopsy of both native and transplanted kidneys. Understanding the underlying causes may help diagnosis and future management. The most frequent cause of CaOx crystal deposition within the kidney is hyperoxaluria. When this is seen in native kidney biopsy, primary hyperoxaluria must be considered and investigated further with biochemical and genetic tests. Secondary hyperoxaluria, for example due to enteric hyperoxaluria following bariatric surgery, ingested ethylene glycol or vitamin C overdose may also cause CaOx deposition in native kidneys. CaOx deposition is a frequent finding in renal transplant biopsy, often as a consequence of acute tubular necrosis and is associated with poorer long-term graft outcomes. CaOx crystal deposition in the renal transplant may also be secondary to any of the causes associated with this phenotype in the native kidney. The pathophysiology underlying CaOx deposition is complex but this histological phenotype may indicate serious underlying pathology and should always warrant further investigation.

Educational review: role of the pediatric nephrologists in the work-up and management of kidney stones.

BACKGROUND: The incidence of nephrolithiasis in children and adolescents is increasing and appears to double every 10 years. The most important role of the pediatric nephrologist is to diagnose and modify various metabolic and non-metabolic risk factors, as well as prevent long-term complications especially in the case of recurrent nephrolithiasis. OBJECTIVE: The purpose of this review is to summarize the existing literature on the etiology and management of pediatric nephrolithiasis. RESULTS: The incidence of kidney stones is increasing; dietary and environmental factors are probably the main causes for this increased incidence. In most pediatric patients, the etiology for the kidney stones can be identified. Metabolic factors, such as hypercalciuria and hypocitraturia, urinary tract infection, and urinary stasis, constitute leading causes. Herein, we review the etiologies, diagnostic work-up, and treatment options for the most prevalent causes of kidney stones. The detrimental effects of excessive dietary sodium, reduced fluid intake, and the benefits of plant-based over animal-based protein consumption on urinary crystal formation are discussed. We also review the long-term complications. CONCLUSIONS: Pediatric nephrologists have an important role in the diagnostic work-up and prevention of recurring nephrolithiasis.

Bone oxaloma-a localized manifestation of bone oxalosis.

Oxalosis is a metabolic disorder characterized by the accumulation of calcium oxalate deposits in various organ systems. Bone oxalosis is a systemic manifestation of oxalosis, in which calcium oxalate deposits accumulate in the skeletal system. This report describes a 69-year-old female patient who presented with right hip pain and was later found to have an osseous mass-like lesion in the right proximal femur, with radiographic findings resembling those of a benign bone tumor. CT-guided biopsy and surgical biopsy showed that the mass had pathologic findings typical of bone oxalosis. Because the patient had no predisposing factors for systemic oxalosis and had no hyperoxalemia or hyperoxaluria, she could be diagnosed with localized bone oxalate deposition disease or bone oxaloma rather than bone oxalosis. This is the first report of this clinical entity to present as a benign-appearing bone mass and without any predisposing systemic causes.

Secondary hyperoxaluria due to pancreatic insufficiency.

BACKGROUND: In this article, we present two cases of patients with acute renal insufficiency with a history of exocrine pancreatic insufficiency. In one case, this was caused by pancreaticoduodenectomy; in the other, by alcohol abuse. Neither patient had considerable proteinuria or haematuria. Their renal biopsies showed tubulopathy with widespread oxalate crystals, characterised by their birefringence in light microscopy. Restricting oxalate intake and prescribing oxalate binding agents reduced serum oxalate levels. Renal function partially recovered in both patients. Oxalate nephropathy is associated with exocrine pancreatic insufficiency, gastric and pancreatic surgery, and inflammatory bowel disease. Normally, dietary calcium binds oxalate to form calcium oxalate, which is excreted in the stool. In patients with pancreatic insufficiency, fatty acids bind calcium instead, allowing oxalate to be absorbed in the colon. The resulting hyperoxaluria can cause oxalate crystal formation, tubulopathy, and renal insufficiency. Treatment relies on decreasing the amount of absorbable oxalate in the intestinal lumen, as well as lowering urinary oxalate concentrations. CONCLUSION: Secondary hyperoxaluria is a common cause of renal insufficiency and should be considered in patients with a medical history of pancreatic insufficiency and progressive kidney injury.

Acute oxalate nephropathy associated with C lostridium difficile infection.

Acute oxalate nephropathy has been associated with chronic diarrheal illness and only one case has been reported due to acute diarrhea secondary to Clostridium difficile colitis. To the best of our knowledge, this is the second case report of acute oxalate nephropathy due to C . difficile colitis. A 75-year-old man with a medical history of hypertension, type 2 diabetes mellitus, chronic kidney disease stage IV, recent C . difficile colitis was admitted for acute kidney injury with a creatinine (Cr) of 8.54 mg/dL (baseline Cr, 2.3-2.6 mg/dL). His urinalysis did not show any eosinophils, casts or crystals. Antinuclear antibody, antineutrophil cytoplasmic antibody, complement levels (C3 and C4) and hepatitis screen were negative; a renal ultrasound visualized no hydronephrosis. A kidney biopsy showed widespread tubular oxalate crystal deposition suggestive of hyperoxaluria as the cause of acute kidney injury. In conclusion, an acute diarrheal illness like C . difficile colitis can cause acute oxalate nephropathy.

"Green Smoothie Cleanse" Causing Acute Oxalate Nephropathy.

Oxalate nephropathy is an uncommon condition that causes acute kidney injury with the potential for progression to end-stage renal disease. Diagnosis is based on the kidney biopsy findings of abundant polarizable calcium oxalate crystals in the epithelium and lumen of renal tubules. We report a case of acute oxalate nephropathy in a 65-year-old woman, temporally associated with the consumption of an oxalate-rich green smoothie juice "cleanse" prepared from juicing oxalate-rich green leafy vegetables and fruits. Predisposing factors included a remote history of gastric bypass and recent prolonged antibiotic therapy. She had normal kidney function before using the cleanse and developed acute kidney injury that progressed to end-stage renal disease. Consumption of such juice cleanses increases oxalate absorption, causing hyperoxaluria and acute oxalate nephropathy in patients with predisposing risk factors. Given the increasing popularity of juice cleanses, it is important that both patients and physicians have greater awareness of the potential for acute oxalate nephropathy in susceptible individuals with risk factors such as chronic kidney disease, gastric bypass, and antibiotic use.

[The Hyperoxalurias]. / Le iperossalurie.

Oxalate (Ox) is an end-product of metabolism, important for poor solubility of its calcium salt in biological fluids. Ox can therefore be found in about 70% of urinary calculi. Hyperoxaluria (HOx) defined as Ox exceeding 0.5 mmol)/day, may cause nephrolithiasis/nephrocalcinosis and may be classified as dietary (DH), enteric (EH) or primary (PH). Fractional intestinal absorption of Ox is less than 10%, but increases to over 20% at calcium intakes below 200 mg/day. DH is often related to low-calcium diets. EH is caused by non-absorbed fatty acids which bind to calcium and lower its concentration in the intestinal lumen. Ox forms more soluble complexes with other cations and results in HOx. Similar mechanisms may cause HOx following bariatric surgery. PHs are the most severe causes of HOx. Three types have so far been described, all being autosomic recessive. PH1 is due to mutations of AGXT gene encoding liver alanine-glyoxylate aminotransferase, PH2 is caused by mutations of GR-HPR gene encoding glyoxylate reductase and PH3 by mutations of HOGA1 encoding for hydroxyl-oxoglutarate aldolase. HOx results from deficient detoxification from glyoxylate, which is oxidized to Ox. The three PHs have different severity, though not always clinically distinguishable. They are identified through genetics and, in PH1, good genotype/phenotype correlations have been established. Thanks to early biochemical and genetic diagnosis, which are crucial to either prevent progression to ESRF or choose adequate transplantation strategies, the outlook of PH patients has dramatically improved in the last decades and will furtherly do in view of new therapeutic strategies.