Campylobacter Colitis as a Trigger for Atypical Hemolytic Uremic Syndrome: About One Case.

We present the case of a 17-year-old Caucasian male whose condition featured acute renal failure, anemia, and deep thrombocytopenia after five consecutive days of diarrhea. Campylobacter coli was identified in stool cultures and, although the direct role of this germ in the pathogenesis of hemolytic uremic syndrome (HUS) remains uncertain to this day, initial presentation was considered broadly consistent with typical HUS. However, the patient showed no signs of spontaneous recovery over time. While secondary investigations showed no abnormalities in ADAMTS13 activity or in the alternate pathway of complement, patient's condition deteriorated. Worsening kidney failure required emergency renal replacement therapy and was followed by cardiac involvement in the form of acute heart failure. Given this unfavorable development, blood samples were drawn to look for mutations in the alternate complement pathway, and eculizumab therapy was initiated without further delay, allowing prompt improvement of cardiac function and recovery of diuresis. Upon discharge, the patient still had to undergo intermittent dialysis, which would later be withdrawn. Genetic analysis ultimately confirmed the presence of a complement factor H mutation associated with a high risk of disease recurrence, indicating long-term continuation of eculizumab therapy.

Membranoproliferative glomerulonephritis after intravitreal vascular growth factor inhibitor injections: A case report and review of the literature.

Systemic administration of agents that inhibit vascular endothelial growth factor (VEGF) and therefore vascular proliferation is often used to treat various cancers. However, these agents are associated with a number of side effects, including proteinuria and renal injury. Intravitreal injection of anti-VEGF agents has become the cornerstone of macular disease treatment. Since these agents cross the blood-retina barrier and enter the circulation, systemic side effects have been reported. We report the novel case of a 57-year-old patient who presented with macular oedema secondary to central retinal vein occlusion, underwent three monthly loading-dose injections with the anti-VEGF agent ranibizumab, and 2 weeks after the second injection presented with biopsy-verified membranoproliferative glomerulonephritis. Twelve weeks after presenting with renal failure and 10 weeks after his last anti-VEGF injection, the patient demonstrated spontaneous recovery of his kidney function. The patient had a history that promoted renal fragility, including hypertension, liver transplantation 6 years earlier for alcohol-related cirrhosis and new-onset diabetes mellitus after transplant. Our literature review and case suggest that although adverse renal events after intravitreal anti-VEGF injections are very rare, ophthalmologists and nephrologists should be aware of this risk.

[A complex case of renal phosphate wasting ]. / Une fuite rénale de phosphates complexe .

We describe here the case report of a young man of 34-years old suffering from a haemorrhagic rectocolitis and presenting with marked hypophosphatemia secondary to an infusion of ferric-carboxymaltose. The renal phosphate wasting was asserted by a very low renal maximal reabsorption rate of phosphate associated with a high plasma FGF-23 level. Three months later we explored the patient and his father since we learnt that both of them had suffered from kidney stones for years with marked hypercalciuria. Kidney stones were composed of weddellite and carbapatite. We suspected a familial phosphate renal wasting syndrome but however no mutation of the renal phosphate carriers could be identified.

A paraneoplastic limbic encephalitis from an anorectal small cell neuroendocrine carcinoma: a case report.

BACKGROUND: Paraneoplastic limbic encephalitis (PLE) is a rare autoimmune neurological syndrome observed in cancer patients. PLE is difficult to diagnose and presents a variable response to treatment, depending on the characteristics of the tumor and neuronal autoantibodies. CASE PRESENTATION: A 64-year-old, Caucasian, non-smoker man presented with a rapidly developing cognitive impairment, personality change, spatial disorientation, and short-term memory loss associated with anorexia and cervical and inguinal lymph nodes. The 18F-FDG PET scan documented intensely hypermetabolic lymph nodes, which histologically corresponded to a metastasis from a small cell neuroendocrine carcinoma. The brain MRI revealed a high T2-weighted FLAIR signal of the hippocamps, consisted with a PLE. The presence of anti-neuronal Hu antibodies confirmed the diagnosis. The patient underwent plasmapheresis, associated to a systemic chemotherapy resulting in a partial and temporary improvement of the neurological symptoms. Four cycles of intravenous immunoglobulins were also necessary. After six cures of chemotherapy, the lymph node metastases regressed. However, a new anorectal lesion was detected and was histologically confirmed as a primary small cell neuroendocrine carcinoma, which was treated with concomitant chemoradiotherapy. At the end of this treatment, the patient showed a rapid tumor progression leading to his death. CONCLUSIONS: This case highlights the rare entity, PLE, which is difficult to diagnose and manage. In addition, this is the first published case of PLE associated with an anorectal small cell neuroendocrine carcinoma, which appeared after completion of systemic chemotherapy.

[Renal hemosiderosis following mechanical hemolysis: An original case report]. / Hémosidérose rénale consécutive à une hémolyse mécanique : un cas original.

Renal hemosiderosis is a rare cause of acute kidney injury, but it can also lead to chronic kidney failure. We report here the case of a 73-year-old patient with acute kidney caused by a massive hemosiderosis following the proximal disinsertion of a prosthesis of the ascendant aorta with chronic aortic dissection. The kidney biopsy revealed the diagnosis, showing massive iron deposits inside the proximal tubules, especially with Perls staining and also diffuse hematic casts in the lumen of the tubules. Pathophysiology of hemosiderosis is well described, as well as protective mechanisms. This case report is one of the numerous different causes of renal hemosiderosis that can be related to genetic, infectious or mechanical hemolysis.

Neutralizing Anti-Rituximab Antibodies and Relapse in Membranous Nephropathy Treated With Rituximab.

Membranous Nephropathy (MN) is an autoimmune disease associated with antibodies against podocyte proteins: M-type phospholipase A2 receptor (PLA2R1) or thrombospondin type-1 domain-containing 7A (THSD7A) in 70 and 3% of patients, respectively. Antibody titer is correlated with disease activity: rising during active disease and decreasing before remission. Therefore, decreasing PLA2R1-Antibodies titer has become an important goal of therapy. Rituximab a chimeric monoclonal antibody induces remission in 60-80% of primary MN patients. All monoclonal antibodies such as rituximab can elicit antidrug antibodies, which may interfere with therapeutic response. We aim to analyze the relevance of anti-rituximab antibodies on the outcome of MN after a first course of rituximab. Forty-four MN patients were included and treated with two 1 g infusions of rituximab at 2-weeks interval. Anti-rituximab antibodies, CD19 count, and clinical response were analyzed. Then, we (i) analyzed the association of anti-rituximab antibodies at month-6 with response to treatment: remission, relapse and the need for another rituximab course; (ii) confirmed if anti-rituximab antibodies could neutralize rituximab B-cells depletion; and (iii) tested whether anti-rituximab antibodies could cross-inhibit new humanized anti-CD20 therapies. Anti-rituximab antibodies were detected in 10 patients (23%). Seventeen patients received a second rituximab course after a median time of 12 months (7-12), following nine cases of resistance and eight relapses. Anti-rituximab antibodies were significantly associated with faster B-cell reconstitution at month-6 (75 [57-89] vs. 2 [0-41] cells/µl, p = 0.006), higher proteinuria 12 months after rituximab infusion (1.7 [0.7; 5.8] vs. 0.6 [0.2; 3.4], p = 0.03) and before treatment modification (3.5 [1.6; 7.1] vs. 1.7 [0.2; 1.7] p = 0.0004). Remission rate 6 months after rituximab was not different according to anti-rituximab status (p > 0.99) but the rate of relapse was significantly higher for patients with anti-rituximab antibodies (p < 0.001). These patients required more frequently a second course of rituximab infusions (7/10 vs. 10/34, p = 0.03). Anti-rituximab antibodies neutralized rituximab activity in 8/10 patients and cross-reacted with other humanized monoclonal antibodies in only two patients. Three patients with anti-rituximab antibodies were successfully treated with ofatumumab. Anti-rituximab antibodies could neutralize rituximab B cells cytotoxicity and impact clinical outcome of MN patients. Humanized anti-CD20 seems to be a satisfying therapeutic alternative for patients with anti-rituximab antibodies and resistant or relapsing MN.

[Icodextrin: What arguments for and against its use as an osmotic agent in peritoneal dialysis]. / Icodextrine : quels arguments pour et contre son utilisation comme agent osmotique en dialyse péritonéale ?

Icodextrin is a glucose polymer derived from starch that is used as an osmotic agent in peritoneal dialysis. Its high molecular weight limits blood absorption and is useful for long dwell since there is few osmotic gradient dispersal. Its benefits are numerous: ltrafiltration optimization and better salt and water control especially in anuric patients with a high peritoneal permeability and also in case of infectious peritonitis, glucose sparing with less metabolic complications and a better preservation of peritoneal membrane, better biocompatibility. However it should not be forgotten that icodextrin has also side effects that must be known: allergies, cases of aseptic peritonitis, overintense water and salt depletion, lymphatic absorption of icodextrin and its metabolites (including maltose) with a risk of false capillary glucose rate estimation and a moderate increase in plasma osmolality. That is why it is not recommended now to use more than one daily icodextrin dwell. Nevertheless, several dialysis units use icodextrin in more than one daily dwell, especially in patients with an important ultrafiltration loss or in those in whom glucose sparing is essential. It seems to profit them with no more side effects. A large multicenter trial is in progress to test the efficacy and safety of icodextrin dwell twice a day in elder incident patients in peritoneal dialysis (DIDo). Moreover, icodextrin is also used combined with glucose in a long dwell (bimodal ultrafiltration) with encouraging results in terms of ultrafiltration and glucose sparing.

Plasma cell neoplasia after kidney transplantation: French cohort series and review of the literature.

Although post-transplant lymphoproliferative disorder (PTLD) is the second most common type of cancer in kidney transplantation (KT), plasma cell neoplasia (PCN) occurs only rarely after KT, and little is known about its characteristics and evolution. We included twenty-two cases of post-transplant PCN occurring between 1991 and 2013. These included 12 symptomatic multiple myeloma, eight indolent myeloma and two plasmacytomas. The median age at diagnosis was 56.5 years and the median onset after transplantation was 66.7 months (2-252). Four of the eight indolent myelomas evolved into symptomatic myeloma after a median time of 33 months (6-72). PCN-related kidney graft dysfunction was observed in nine patients, including six cast nephropathies, two light chain deposition disease and one amyloidosis. Serum creatinine was higher at the time of PCN diagnosis than before, increasing from 135.7 (±71.6) to 195.9 (±123.7) µmol/l (p = 0.008). Following transplantation, the annual rate of bacterial infections was significantly higher after the diagnosis of PCN, increasing from 0.16 (±0.37) to 1.09 (±1.30) (p = 0.0005). No difference was found regarding viral infections before and after PCN. Acute rejection risk was decreased after the diagnosis of PCN (36% before versus 0% after, p = 0.004), suggesting a decreased allogeneic response. Thirteen patients (59%) died, including twelve directly related to the hematologic disease. Median graft and patient survival was 31.7 and 49.4 months, respectively. PCN after KT occurs in younger patients compared to the general population, shares the same clinical characteristics, but is associated with frequent bacterial infections and relapses of the hematologic disease that severely impact the survival of grafts and patients.

A de novo monoclonal immunoglobulin deposition disease in a kidney transplant recipient: a case report.

INTRODUCTION: Myeloma following kidney transplantation is a rare entity. It can be divided into two groups: relapse of a previous myeloma and de novo myeloma. Some of these myelomas can be complicated by a monoclonal immunoglobulin deposition disease, which is even less common. Less than ten cases of monoclonal immunoglobulin deposition disease after renal graft have been reported in the literature. The treatment of these patients is not well codified. CASE PRESENTATION: We report the case of a 43-year-old white European man who received a renal transplant for a nephropathy of unknown etiology and developed a nephrotic syndrome with kidney failure at 2-years follow-up. We diagnosed a de novo monoclonal immunoglobulin deposition disease associated with a kappa light chain multiple myeloma, which is a very uncommon presentation for this disease. Three risk factors were identified in this patient: Epstein-Barr virus reactivation with cytomegalovirus co-infection; intensified immunosuppressive therapy during two previous rejection episodes; and human leukocyte antigen-B mismatches. Chemotherapy treatment and decrease in the immunosuppressive therapy were followed by remission and slight improvement of renal function. A relapse occurred 8 months later and his renal function worsened rapidly requiring hemodialysis. He died from septic shock 4 years after the diagnosis of monoclonal immunoglobulin deposition disease. CONCLUSIONS: This rare case of post-transplant lymphoproliferative disorder with an uncommon presentation illustrates the fact that treatment in such a situation is very difficult to manage because of a small number of patients reported and a lack of information on this disease. There are no guidelines, especially concerning the immunosuppressive therapy management.