Acute kidney injury induced by thrombotic microangiopathy in a patient with hemophagocytic lymphohistiocytosis.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a fatal clinical syndrome characterized by excessive immune activation and inflammation. It is frequently complicated by acute kidney injury (AKI) that often develops as acute tubular necrosis (ATN). Meanwhile, renal thrombotic microangiopathy (TMA) is a rare pathologic finding that mostly occurs in hemolytic uremic syndrome or thrombotic thrombocytopenic purpura. There are only few reports on TMA developing in patients with HLH. We present here a rare case of TMA associated HLH. CASE PRESENTATION: A 60-year-old woman was admitted for a fever of unknown origin that had persisted for several weeks. She presented with AKI and pancytopenia. Clinical, laboratory and bone marrow biopsy findings met the criteria of HLH. Kidney biopsy showed TMA and minimal ATN, which suggested that the primary cause of AKI was TMA in this case. Because of sustained oliguria, we initiated hemodialysis (HD) and also decided to use chemotherapy composed of dexamethasone, etoposide and cyclosporine for treatment of HLH. Six months after the initiation of chemotherapy, pancytopenia was completely resolved, indicating the resolution of HLH. At the same time, serum creatinine decreased to a normal range without the need for HD, suggesting the resolution of TMA. CONCLUSION: We report a case of renal TMA associated HLH. This case suggests that renal TMA should be considered as a primary cause of AKI in patients with underlying HLH.

Association of Erythropoietin-Stimulating Agent Responsiveness with Mortality in Hemodialysis and Peritoneal Dialysis Patients.

Erythropoiesis-stimulating agent (ESA) responsiveness has been reported to be associated with increased mortality in hemodialysis (HD) patients. ESA requirement to obtain the same hemoglobin (Hb) level is different between HD and peritoneal dialysis (PD) patients. In this study, we investigated the impact of ESA responsiveness on mortality between both HD and PD patients. Prevalent HD and PD patients were selected from the Clinical Research Center registry for end-stage renal disease, a prospective cohort study in Korea. ESA responsiveness was estimated using an erythropoietin resistant index (ERI) (U/kg/week/g/dL). Patients were divided into three groups by tertiles of ERI. ESA responsiveness was also assessed based on a combination of ESA dosage and hemoglobin (Hb) levels. The primary outcome was all-cause mortality. A total of 1,594 HD and 876 PD patients were included. The median ESA dose and ERI were lower in PD patients compared with HD patients (ESA dose: 4000 U/week vs 6000 U/week, respectively. P<0.001, ERI: 7.0 vs 10.4 U/kg/week/g/dl, respectively. P<0.001). The median follow-up period was 40 months. In HD patients, the highest ERI tertile was significantly associated with higher risk for all-cause mortality (HR 1.96, 95% CI, 1.07 to 3.59, P = 0.029). HD patients with high-dose ESA and low Hb levels (ESA hypo-responsiveness) had a significantly higher risk of all-cause mortality (HR 2.24, 95% CI, 1.16 to 4.31, P = 0.016). In PD patients, there was no significant difference in all-cause mortality among the ERI groups (P = 0.247, log-rank test). ESA hypo-responsiveness was not associated with all-cause mortality (HR = 1.75, 95% CI, 0.58 to 5.28, P = 0.319). Our data showed that ESA hypo-responsiveness was associated with an increased risk of all-cause mortality in HD patients. However, in PD patients, ESA hypo-responsiveness was not related to all-cause mortality. These finding suggest the different prognostic value of ESA responsiveness between HD and PD patients.

The impact of kidney transplantation on 24-hour ambulatory blood pressure in end-stage renal disease patients.

In this study, we prospectively investigated the impact of kidney transplantation (KT) on the status of hypertension, including circadian rhythm in end-stage renal disease (ESRD) patients. We performed 24-hour ambulatory blood pressure (BP) monitoring and office BP measurement in 48 patients before and 1 year after KT. According to the nocturnal reduction in systolic BP (ΔSBP), the patients were divided into dippers, non-dippers, and reverse dippers. After KT, the mean BP value in office BP and 24-hour ambulatory BP monitoring did not change, but the proportion of patients taking anti-hypertensive drugs and the pill number significantly decreased. In contrast, the mean ΔSBP significantly decreased, and the proportion of non-dippers and reverse dippers did not decrease. Decrease in ΔSBP after KT was associated with inferior allograft function during follow-up. Our study suggests that KT improved the overall BP level, but it did not affect abnormal circadian rhythm in ESRD patients.

Fatal Breakthrough Mucormycosis in an Acute Myelogenous Leukemia Patient while on Posaconazole Prophylaxis.

Posaconazole is a new oral triazole with broad-spectrum antifungal activity. Posaconazole has also shown a significant advantage of preventing invasive fungal infection compared to fluconazole or itraconazole in patients with prolonged neutropenia. Indeed, posaconazole has been commonly used for antifungal prophylaxis in patients undergoing remission induction chemotherapy for acute myelogenous leukemia or myelodysplastic syndrome. We experienced a case of fatal mucormycosis despite posaconazole prophylaxis. To our knowledge, this is the first reported case of fatal breakthrough mucormycosis in a patient receiving posaconazole prophylaxis during remission induction chemotherapy in Korea. This case demonstrated that breakthrough fungal infection can occurs in patients receiving posaconazole prophylaxis because of its limited activity against some mucorales.

Mucosal schwann-cell hamartoma diagnosed by using an endoscopic snare polypectomy.

Colorectal polyps of mesenchymal origin are a rare group of colorectal disorders. A "mucosal Schwann-cell hamartoma," which is one type of polypoid lesion that originates from the mesenchyme, is a newly-proposed disease entity to be distinguished from the neurofibromas found in type-1 neurofibromatosis. This lesion is composed of pure Schwann-cell proliferation in the lamina propria and shows diffuse immunoreactivity for the S-100 protein. We report a case of a polypoid lesion of the colon with the features of this recently-proposed disease entity.

Successful percutaneous aspiration thrombectomy for acute mesenteric ischemia in a patient with atrial fibrillation despite optimal anticoagulation therapy.

This report describes a case of acute mesenteric ischemia due to acute superior mesenteric artery (SMA) thromboembolism in a patient with chronic atrial fibrillation despite optimal anticoagulation therapy. The patient underwent SMA angiography and endovascular revascularization for acute mesenteric ischemia. We initially tried endovascular thrombolytic therapy for the thromboembolism of SMA, but it did not achieve complete revascularization. Therefore, we performed a percutaneous aspiration thrombectomy, which led to complete revascularization and successful treatment of acute mesenteric ischemia without any additional procedures.

Successful treatment of protein-losing enteropathy due to AA amyloidosis with octreotide in a patient with rheumatoid arthritis.

Protein-losing enteropathy (PLE) is a rare syndrome of gastrointestinal protein loss that may complicate a variety of diseases. This excessive protein loss across the gut epithelium can be explained by several mechanisms, such as augmentation of the intestinal mucosal capillary permeability, mucosal disruption, intestinal or mesenteric vasculitis, and lymphangiectasia. However, these pathophysiologic alterations of the gut are closely linked to the underlying cause, and primary treatment for PLE should be directed at the underlying condition. Here, we report a female patient with rheumatoid arthritis who developed severe PLE due to AA amyloidosis and was successfully treated with octreotide. She had been suffered from rheumatoid arthritis for 18 years, and her arthritic symptoms at the time of presentation were not definite but manifested as severe diarrhea and general edema with hypoalbuminemia. PLE due to gastrointestinal amyloidosis was confirmed by increased fecal α1-antitrypsin clearance and a colonoscopic biopsy that was positive for amyloid deposits. The diarrhea dissipated with conventional treatment, but the general edema resolved only after introducing a long-acting somatostatin analog (octreotide), along with a gradual recovery of the serum albumin level. This case teaches us that in the case of PLE due to AA amyloidosis that is refractory to conventional treatment, the administration of octreotide should be considered.

Recurrent Insulin Autoimmune Syndrome Caused by α-Lipoic Acid in Type 2 Diabetes.

Insulin autoimmune syndrome (IAS) is characterized by spontaneous hypoglycemia caused by insulin autoantibodies in the absence of exogenous insulin administration. Some drugs containing sulfhydryl compounds are known to initiate the onset of IAS. A 67-year-old female who had diabetes for 5 years visited the outpatient clinic at our institution due to diabetic peripheral polyneuropathy. She was prescribed α-lipoic acid (ALA), which contains two sulfur atoms. Two weeks later, she complained of recurrent hypoglycemic symptoms. We detected a high level of insulin and high titers of insulin autoantibodies. Her human leukocyte antigen (HLA) genotype included the DRB1*0406 allele, which indicates a high level of susceptibility to IAS. She was treated with prednisolone. After this episode, she experienced two more hypoglycemic events after taking ALA for diabetic neuropathy in other hospitals. As ALA can be used to treat diabetic peripheral polyneuropathy, physician discretion is advised based on the possibility of IAS due to ALA in diabetic patients.