Magnesium sulphate in patients with thrombotic thrombocytopenic purpura (MAGMAT): a randomised, double-blind, superiority trial.

PURPOSE: Studies have suggested benefits from magnesium sulphate in thrombotic thrombocytopenic purpura (TTP). We aimed to measure the effects of magnesium sulphate supplementation on TTP recovery. METHODS: In this multicenter, randomised, double-blind, controlled, superiority study, we enrolled adults with a clinical diagnosis of TTP. Patients were randomly allocated to receive magnesium sulphate (6 g intravenously followed by a continuous infusion of 6 g/24 h for 3 days) or placebo, in addition to the standard treatment. The primary outcome was the median time to platelet normalisation (defined as a platelet count ≥ 150 G/L). Efficacy and safety were assessed by intention-to-treat. RESULTS: Overall, we enrolled 74 participants, including one who withdrew his/her consent. Seventy-three patients were further analyzed, 35 (48%) allocated to magnesium sulphate and 38 (52%) to placebo. The median time to platelet normalisation was 4 days (95% confidence interval [CI], 3-4) in the magnesium sulphate group and 4 days (95% CI 3-5) in the placebo group. The cause-specific hazard ratio of response was 0.93 (95% CI 0.58-1.48, p = 0.75). The number of patients with ≥ 1 serious adverse reactions was similar in the two groups. By day 90, four patients in the magnesium sulphate group and two patients in the placebo group had died (p = 0.42). The most frequent adverse event was low blood pressure occurring in 34% in the magnesium sulphate group and 29% in the placebo group (p = 0.80). CONCLUSION: Among patients with TTP, the addition of magnesium sulphate to the standard of care did not result in a significant improvement in time to platelet normalisation.

JAK inhibition for CD3- CD4+ lymphocytic-variant hypereosinophilic syndrome.

Alternatives are urgently needed in patients with CD3- CD4+ lymphocytic-variant hypereosinophilic syndrome (L-HES) requiring high-level steroids or who are unresponsive and/or intolerant to conventional alternative therapies. We report five L-HES patients (44-66 years) with cutaneous involvement (n = 5) and persistent eosinophilia (n = 3) despite conventional therapies, who successfully received JAK inhibitors (tofacitinib n = 1, ruxolitinib n = 4). JAKi led to complete clinical remission in the first 3 months in all (with prednisone withdrawal in four). Absolute eosinophil counts normalized in cases receiving ruxolitinib, while reduction was partial under tofacitinib. After switch from tofacitinib to ruxolitinib, complete clinical response persisted despite prednisone withdrawal. The clone size remained stable in all patients. After 3-13 months of follow-up, no adverse event was reported. Prospective clinical trials are warranted to examine the use of JAKi in L-HES.

Multiple Severe Toxicities of L-Asparaginase and Their Innovative Management during Induction Therapy of Acute Lymphoblastic Leukemia in an Adult Patient.

L-asparaginase is a key chemotherapeutic agent in acute lymphoblastic leukemia (ALL). It is also known for multiple and severe specific toxicities, without consensual management. We report the case of a 51-year-old man treated with L-asparaginase for recently diagnosed T-cell ALL. During the treatment, he developed a coma due to multifactorial diffuse cerebral edema, by hepatic encephalopathy, cerebral venous thrombosis, and hyperammonemia, all linked to toxicity of L-asparaginase. Specific and innovative treatments were employed to manage these toxicities: supplementation with L-carnitine, thiamine, and pyridoxine for hepatic toxicity, perfusion of sodium benzoate to decrease ammonemia, and extrahepatic albumin-based dialysis sessions, along with anticoagulation. The patient improved within two weeks and is currently alive 13 months later, in first complete remission, without sequelae, on an alleviated chemotherapy regimen.

Oxalate nephropathy following vitamin C intake within intensive care unit
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OBJECTIVE: To report a case of acute oxalate nephropathy related to vitamin C intake within the intensive care unit (ICU). DESIGN: Case report. SETTING: ICU and nephrology department of a French university hospital. PATIENT: A 57-year-old woman with septic shock related to Legionella pneumophila pneumonia complicated by acute respiratory distress syndrome and acute kidney injury who required renal replacement therapy for 75 days. MEASUREMENTS AND MAIN RESULTS: A renal biopsy was performed on day 72 because of persistent anuria and because the patient showed characteristic features of severe acute oxalate nephropathy. The only cause identified was vitamin C intake received during hospitalization within the ICU (~ 30 g over 2.5 months). At month 6 after ICU admission, estimated glomerular filtration rate was 24 mL/min/1.73m2. CONCLUSION: Compelling evidence obtained from in-vitro and animal studies suggest that vitamin C, a circulating antioxidant, may be a valuable adjunctive therapy in critically-ill patients. Data from humans are more conflicting. Oxalate, a well-known metabolite of vitamin C, is excreted by the kidneys and can exert a toxic effect on epithelial cells and causes direct tubular damage, and/or it can crystallize within the tubular lumen. This case highlights an under-recognized secondary adverse event from vitamin C given to critically-ill patients. The use of high-dose vitamin C should be prescribed with caution in this population.
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[HNF1B-related disease: paradigm of a developmental gene and unexpected recognition of a new renal disease]. / HNF1B : paradigme d'un gène du développement et émergence inattendue d'une nouvelle maladie génétique rénale.

HNF1B encodes for a transcription factor involved in the early development of the kidney, pancreas, liver and genital tract. Mutations in HNF1B are dominantly inherited and consist of whole-gene deletion, or small mutation. De novo mutation occurs in half of tested kindreds. HNF1B-related disease combines renal and non-renal manifestations. Renal involvement is heterogeneous and may escape early recognition. During fetal life and childhood, it mostly consists of hyperechogenic kidneys or bilateral renal cystic hypodysplasia. The adult phenotype encompasses tubulointerstitial profile at presentation and slowly progressive renal decline (-2 ml/min/year). Renal involvement includes renal cysts (mostly few cortical cysts), a solitary kidney, pelvi-caliceal abnormalities, hypokalemia and hypomagnesemia related to tubular leak, and more rarely, Fanconi syndrome and chromophobe renal carcinoma. The latter warrants ultrasound screening. Extrarenal phenotype consists of diabetes mellitus (MODY-5), exocrine pancreas failure and pancreas atrophy; fluctuation liver tests abnormalities; diverse genital tract abnormalities in females or infertility in males; and mild mental retardation in rare individuals. Phenotype heterogeneity within families is striking. Individuals progressing to end-stage renal disease are eligible for kidney transplantation (or combined pancreas and kidney transplantation for diabetic individuals). While HNF1B disease was still unknown one decade ago, it has emerged as the second most prevalent dominantly inherited kidney disease. Data available pave the way for early recognition and improved specific management, including genetic counselling.

Oxalate nephropathy associated with chronic pancreatitis.

BACKGROUND AND OBJECTIVES: Enteric overabsorption of oxalate may lead to hyperoxaluria and subsequent acute oxalate nephritis (AON). AON related to chronic pancreatitis is a rare and poorly described condition precluding early recognition and treatment. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We collected the clinical characteristics, treatment, and renal outcome of 12 patients with chronic pancreatitis-associated AON followed in four French renal units. RESULTS: Before AON, mild to moderate chronic kidney disease was present in all patients, diabetes mellitus in eight (insulin [n = 6]; oral antidiabetic drugs [n = 2]), and known chronic pancreatitis in only eight. At presentation, pancreas imaging showed gland atrophy/heterogeneity, Wirsung duct dilation, calcification, or pseudocyst. Renal findings consisted of rapidly progressive renal failure with tubulointerstitial profile. Acute modification of glomerular filtration preceded the AON (i.e., diarrhea and diuretics). Increase in urinary oxalate excretion was found in all tested patients and hypocalcemia in nine (<1.5 mmol/L in four patients). Renal biopsy showed diffuse crystal deposits, highly suggestive of oxalate crystals, with tubular necrosis and interstitial inflammatory cell infiltrates. Treatment consisted of pancreatic enzyme supplementation, oral calcium intake, and an oxalate-free diet in all patients and renal replacement therapy in five patients. After a median follow-up of 7 months, three of 12 patients reached end-stage renal disease. CONCLUSION: AON is an under-recognized severe crystal-induced renal disease with features of tubulointerstitial nephritis that may occur in patients with a long history of chronic pancreatitis or reveal the pancreatic disease. Extrinsic triggering factors should be prevented.

Renal, ocular, and neuromuscular involvements in patients with CLDN19 mutations.

BACKGROUND AND OBJECTIVES: The objective of this study was to describe the renal and extrarenal findings in patients with recessively inherited familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) associated with CLDN19 mutations. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Medical records of three patients from two French unrelated families with CLDN19 mutations were retrospectively examined. RESULTS: Direct sequencing of CLDN19 identified a known variant (p.Gly20Asp) in all patients and a new missense mutation (p.Val44Met) in one (compound heterozygous). The patients' renal phenotype closely mimicked CLDN16-related nephropathy: low serum Mg2+ (<0.65 mmol/L) despite oral supplementation, hypercalciuria partly thiazide-sensitive, and progressive renal decline with ESRD reached at age 16 and 22 years in two individuals. Primary characteristics (failure to thrive, recurrent urinary tract infections, or abdominal pain), age at onset (0.8 to 16 years), and rate of renal decline were highly heterogeneous. Ocular involvement was identified in all patients, although two patients did not have visual loss. Additionally, exercise intolerance with pain, weakness, and electromyographical alterations mimicking a Ca2+/K+ channelopathy (pattern V) were observed in two of three individuals. These features persisted despite the normalization of serum K+ and Mg2+ after renal transplantation. CONCLUSIONS: Ocular manifestations, even subtle, and exercise intolerance mimicking mild to moderate periodic paralysis are two symptoms that need to be searched for in patients with FHHNC and may indicate CLDN19 mutations.