Necrotizing fasciitis of thigh associated with Escherichia Coli bacteremia in a patient on chronic hemodialysis

Necrotizing fasciitis is a lethal soft tissue infection for its rapid progression to septic shock. We present a 59‐year‐old male on chronic hemodialysis (HD). We made the diagnosis of necrotizing fasciitis of the right thigh due to the crepitus from physical examination and subcutaneous emphysema from an X film. He was successfully treated with antibiotics and surgical debridement. The blood and surgical drainage cultures showed Escherichia coli, which is less commonly seen in cutaneous infection. The colonoscopic finding revealed adenomatous polyps. Necrotizing fasciitis in patients on HD requires early diagnosis and aggressive treatment to ensure the favorable clinical outcomes.     

Catheter‐related fungal endocarditis caused by Candida parapsilosis in a hemodialysis patient

Fungal endocarditis (FE) is commonly regarded as a rare but fatal disease. The incidence of infective endocarditis (IE) in hemodialysis (HD) patients is thought to be obviously higher than that in the general population. Moreover, IE occurs more likely in HD patients with catheters. With the increase of HD population and extensive use of catheters in HD patients, FE, as a special form of IE, may increase and bring new challenges to clinicians. We reported a case of FE associated with catheter infection in a 44‐year‐old woman on HD. The risk factors and treatment strategies of FE in HD patients were discussed.     

Case report of Capnocytophaga canimorsus septicemia with infective endocarditis in a hemodialysis patient: A not widely known dog pathogen

Keeping pets as a companion is a global phenomenon. This relationship, however, is not entirely free of risk as some diseases can be transmitted to human beings. It is important to emphasize safety among pet owners, particularly in people with chronic illness as they may have increased vulnerability to infection which could arise from an intimate relationship. We report an uncommon etiology of sepsis complicated with infective endocarditis in a 63-year old dog-owner who was on hemodialysis. To the best of our knowledge, this is the first case of Capnocytophaga canimorsus infective endocarditis (IE) ever reported in a patient undergoing hemodialysis.     

Infective endocarditis in a hemodialysis patient: a dreaded complication

Infection is the most common cause of death in hemodialysis patients, after cardiovascular disease. Dialysis access infections, with secondary septicemia, contribute significantly to patient mortality. The most common source is temporary catheterization. Bacteremia occurs commonly in patients receiving hemodialysis, with infective endocarditis being a relatively uncommon, but potentially lethal complication. Valvular calcification is the most significant risk factor. The diagnosis of infective endocarditis is made clinically and confirmed with the echocardiographic modified Duke's criteria. The most common pathogen is Staphylococcus aureus and the mitral valve is the most common site. Staphylococcus aureus infective endocarditis is commonly associated with embolic phenomenon. A high index of suspicion is critical in the early recognition and management of infective endocarditis. However, prevention of bacteremia is undoubtedly the best strategy with the early placement of arteriovenous fistulae. In the case of temporary catheterization, the use of topical mupirocin or polysporin and gentamicin and/or citrate locking is beneficial. Although catheter salvage has not been studied in randomized trials, catheter removal remains standard therapy during bacteremia.     

Iliopsoas abscess as a complication of tunneled jugular vein catheterization in a hemodialysis patient

Iliopsoas abscess is a rare complication in hemodialysis patients that is mainly due to adjacent catheterization, local acupuncture, discitis, and bacteremia. Herein, we report a 47‐year‐old woman undergoing regular hemodialysis via a catheter in the internal jugular vein who presented with low back pain and dyspnea. A heart murmur suggested the presence of catheter‐related endocarditis, and this was confirmed by an echocardiogram and a blood culture of methicillin‐resistant Staphylococcus aureus. A computed tomography indicated a pulmonary embolism and an incidental finding of iliopsoas abscess. Following surgical intervention and intravenous daptomycin, the patient experienced full recovery and a return to usual activities. This case indicates that an iliopsoas abscess can be related to a jugular vein catheter, which is apparently facilitated by infective endocarditis. The possibility of iliopsoas abscess should be considered when a hemodialysis patient presents with severe low back pain, even when there is no history of adjacent mechanical intervention.     

一种蛋白质纯化流程用于提纯大肠杆菌表达的蛋白片段

用一种新的蛋白质纯化流程提纯由大肠杆菌表达的夏氏疟原虫AMA1片段。大肠杆菌表达的片段首先用镍柱提纯，提纯后的蛋白用DTT还原，对盐酸胍透析，再对空气氧化。用RP－HPLC对片段二次提纯，通过冻干转换缓冲液。SDS－PAGE、RP－HPLC和质谱分析都显示，经这种纯化流程提纯的蛋白有很高的纯度，且二硫键已完全正确形成。提示这一蛋白质纯化流程可用于由大肠杆菌表达的低分子量寡二硫键的蛋白。     

Catheter-related bacteremia caused by Comamonas testosteroni in a hemodialysis patient

Comamonas testosteroni has rarely been implicated as a human pathogen. In general, the outcome of C. testosteroni infections is favorable. We report a case of fatal bacteremia caused by C. testosteroni in a 64-year-old woman on hemodialysis.     

枯草芽孢杆菌植酸酶基因在大肠杆菌中的表达及其对酶热稳定性的影响

采用PCR法,获得不含有信号肽序列的来源于枯草芽孢杆菌的植酸酶phyC基因的非融合和融合表达片段,分别构建带有T7lac启动子的大肠杆菌的植酸酶pET30NFphyC和pET30FphyC表达载体,并转入大肠杆菌BL21(DE3)。大肠杆菌分别在30℃和25℃经IPTG诱导后实现了植酸酶的表达,非融合和融合植酸酶的表达量分别约占菌体总蛋白的13％和15％,分子量分别为40．13kDa和43．27kDa。表达产物具有植酸酶的生物学活性,非融合植酸酶和融合植酸酶的最适反应温度分别为50℃和75℃,经90℃处理10min,残留酶活性分别为37℃时的31．9％和75．7％。分析表明,含13个氨基酸残基的融合片段有助于植酸酶的表达和酶热稳定性的提高。     

Cerebral microbleeds and cognitive decline in a hemodialysis patient: Case report and review of literature

Cerebral microbleeds (CMBs) are small hemosiderin deposits indicative of prior cerebral microscopic hemorrhage and previously thought to be clinically silent. Recent population‐based cross‐sectional studies and prospective longitudinal cohort studies have revealed association between CMB and cognitive dysfunction. In the general population, CMBs are associated with age, hypertension, and cerebral amyloid angiopathy. In the chronic kidney disease (CKD) population, diminished estimated glomerular filtration rate has been found to be an independent risk factor for CMB, raising the possibility that a uremic milieu may predispose to microbleeds. In the end‐stage renal disease (ESRD) population on hemodialysis, the incidence of microbleeds is significantly higher compared with a control group without history of CKD or stroke. We present an ESRD patient on chronic hemodialysis with a history of gradual cognitive decline and progressive CMBs. Through this case and literature review, we illustrate the need to develop detection and prediction models to treat this frequent development in ESRD patients.     

Bilateral quadriceps and triceps tendon rupture in a hemodialysis patient

This paper presented a 58‐year‐old hemodialysis patient who had bilateral quadriceps and triceps tendon rupture, whereby the role of rehabilitation in functional parameters has been highlighted.     

Lactic acidosis induced by metformin in a chronic hemodialysis patient with diabetes mellitus type 2

Metformin is a biguanide group oral antidiabetic drug used for the treatment of type 2 diabetes mellitus. Nausea, vomiting, diarrhea, abdominal pain, and anorexia are the most common adverse effects encountered during treatment. Lactic acidosis is a serious side effect seen with metformin use, and while the incidence of lactic acidosis is similar to other oral antidiabetics, metformin is not recommended to patients with certain risk factors, such as cardiovascular, pulmonary, and renal and liver failure. We describe a chronic hemodialysis patient treated with metformin, presenting to the nephrology department with altered mental status.     

大肠杆菌热敏肠毒素和耐热肠毒素基因融合及其免疫原性研究

采用基因工程技术将编码大肠杆菌热敏肠毒素亚单位（ＬＴＢ）基因和耐热肠毒素（ＳＴ）基因进行体外重组,得到的融合基因能在大肠杆菌中表达。重组菌株免疫动物后,均能诱发产生抗ＬＴ和ＳＴ抗体。实验结果表明,ＬＴ／ＳＴ融合蛋白不仅保持了ＬＴＢ的免疫原性和与神经节甙酯ＧＭ１的结合能力,而且也赋予本来没有免疫原性的ＳＴ免疫原性,并极大地降低了ＳＴ的生物毒性,为构建理想的致腹泻大肠菌苗奠定了基础。     

Acquired reactive perforating collagenosis and pseudoporphyric bullous dermatosis in a hemodialysis patient

Hemodialysis patients present with a broad spectrum of specific and nonspecific skin disorders, which rarely coexist. We report an exceptional case of a hemodialysis patient that developed acquired reactive perforating collagenosis and pseudoporphyric bullous dermatosis on the basis of common skin disorders which include hyperpigmentation, pruritus, xerosis cutis, and Linsday's nails. Interestingly, our patient presented with two unusual but distinctive cutaneous dermopathies on the background of other commonly seen skin alterations. The patient was successfully treated with allopurinol and N‐acetylcysteine. Avoidance of potentially triggering factors such as alcohol, sunlight exposure and certain medication was recommended. Thus, increasing clinical awareness, assiduous investigation and early treatment of skin disorders are required to improve the prognosis and quality of life in this patient population.     

Type I (sporadic) porphyria cutanea tarda in a hemodialysis patient: a case report

A hemodialysis patient with hepatitis C virus infection developed painful blisters on her hands that burst spontaneously. She was found to have serum porphyrin levels >2000 nmol/L. A punch biopsy revealed subepidermal blistering with festooning of dermal papillae associated with a mixed inflammatory infiltrate. Based on the clinical, biochemical, and histologic findings, a diagnosis of porphyria cutanea tarda was made. Treatment was started with twice-weekly phlebotomy and oral hydroxychloroquine and significant clinical improvement resulted.     

Beneficial effects of nocturnal hemodialysis in a hemodynamically unstable patient with AL‐amyloidosis

We present a patient with primary systemic AL‐amyloidosis, who stabilized hemodynamically on nocturnal hemodialysis (NHD). The NHD allowed a significant reduction in ultrafiltration rates which likely underlies the procedural tolerability. It also provided an increase in urea clearance, better control of serum phosphorus levels without the use of any binders, and normalization of blood pressure despite the discontinuation of all antihypertensive agents. Given the autonomic derangements associated with AL‐amyloidosis pathophysiology and the clinical benefits of NHD on hemodynamic stability, the use of intensive hemodialysis may be considered for the management of patients with unstable hemodynamic profiles.     

Polycythemia due to obstructive sleep apnea in a patient on hemodialysis

Both anemia and sleep disordered breathing are common in patients with dialysis‐dependent stage 5 chronic kidney disease. Erythrocytosis resulting from obstructive sleep apnea (OSA) is rare in the general population and has never been described in the hemodialysis population. We present a case of asymptomatic isolated erythrocytosis and elevated serum erythropoietin level in an otherwise well and previously erythropoietin‐dependent chronic hemodialysis patient with chronic kidney disease secondary to ischemic nephropathy. There was no history or symptoms of cardio‐pulmonary or hepatic diseases nor any relevant family history. Screening work‐up for malignancies was negative. The clinical history was highly suggestive of OSA and severe OSA (respiratory disturbance index of 59) was confirmed by polysomnographic studies. Successful treatment of the OSA with continuous positive airway pressure resulted in permanent stabilization of the hemoglobin to levels below 13 g/dL without the need for repeated phlebotomies and in dramatic lowering of serum erythropoietin levels. To our knowledge, this is the first case of OSA mediated erythrocytosis in a dialysis patient documented in the literature.     

Heparin‐induced thrombocytopenia due to heparin lock in a hemodialysis patient: A case report

Heparin‐induced thrombocytopenia (HIT) is a potentially fatal clinical condition which can develop after exposure to unfractionated or low‐molecular‐weight heparins. Even small doses of heparin such as heparin flushes in hemodialysis catheter can induce the development of HIT. However, the true incidence of heparin lock‐related HIT is unknown. We report a 58‐year‐old woman with acute kidney injury because of obstructive uropathy who developed HIT after heparin‐free hemodialysis. She was found to have severe thrombocytopenia with deep vein thrombosis of left lower limb and arterial thrombosis of the right anterior and middle cerebral arteries. The heparin‐platelet factor 4 antibody was positive and she was put on plasmapharesis. However, her condition further deteriorated and succumbed shortly. Heparin lock solution in the hemodialysis catheter was believed to be the cause of HIT in our patient.     

Secondary sternal Aspergillus osteomyelitis in a diabetic hemodialysis patient with previous allograft rejection

A 29-year-old diabetic woman who had a previously failed renal allograft on maintenance hemodialysis developed sternal aspergillosis with Aspergillus terreus following a pericardiectomy. She was successfully treated with surgical debridement and a combination of antifungal agents including amphotericin B, caspofungin, and voriconizole. The diagnostic difficulties and management are discussed.     

Digital infarction in a hemodialysis patient due to embolism from a thrombosed brachial arteriovenous fistula

Acute onset of digital ischemia and infarction is an unusual complication in patients undergoing hemodialysis. This is a report of a patient on regular hemodialysis who presented with acute distal extremity ischemia, progressing to digital infarction and on evaluation was found to have thrombosis of brachial arteriovenous fistula with embolization to the distal arteries causing digital artery occlusion.