Complications of chronic kidney disease: anemia, mineral metabolism, and cardiovascular disease

Patient delay in chronic kidney disease: A qualitative study

This study aimed to investigate the reasons for patient delay in chronic kidney disease (CKD) and provide a scientific basis for implementing effective interventions. With the adoption of the phenomenological method in qualitative research, semi-structured, face-to-face interviews were conducted with 14 cases, and the Colaizzi seven-step analysis method was used to analyze the interview data and refine the themes. A total of 4 themes were obtained, namely, a cognitive explanation of illness, negative psychological emotions, socioeconomic levels, and limited medical resources. The current status of patient delay in chronic kidney disease is serious, and there are various reasons for it. Health management departments and healthcare providers at all levels should pay attention to this situation and provide targeted supportive interventions and health education to help patients establish the correct awareness of medical consultation and effectively improve their quality of survival.

Pyrroloquinoline-Quinone Is More Than an Antioxidant: A Vitamin-like Accessory Factor Important in Health and Disease Prevention

Pyrroloquinoline quinone (PQQ) is associated with biological processes such as mitochondriogenesis, reproduction, growth, and aging. In addition, PQQ attenuates clinically relevant dysfunctions (e.g., those associated with ischemia, inflammation and lipotoxicity). PQQ is novel among biofactors that are not currently accepted as vitamins or conditional vitamins. For example, the absence of PQQ in diets produces a response like a vitamin-related deficiency with recovery upon PQQ repletion in a dose-dependent manner. Moreover, potential health benefits, such as improved metabolic flexibility and immuno-and neuroprotection, are associated with PQQ supplementation. Here, we address PQQ's role as an enzymatic cofactor or accessory factor and highlight mechanisms underlying PQQ's actions. We review both large scale and targeted datasets demonstrating that a neonatal or perinatal PQQ deficiency reduces mitochondria content and mitochondrial-related gene expression. Data are reviewed that suggest PQQ's modulation of lactate acid and perhaps other dehydrogenases enhance NAD+-dependent sirtuin activity, along with the sirtuin targets, such as PGC-1α, NRF-1, NRF-2 and TFAM; thus, mediating mitochondrial functions. Taken together, current observations suggest vitamin-like PQQ has strong potential as a potent therapeutic nutraceutical.

Hypertensive emergency and seizures during haemodialysis

Intracranial abscesses are uncommon, serious and life-threatening infections. A brain abscess is caused by inflammation and collection of infected material, coming from local or remote infectious sources. Patients with chronic kidney disease on dialysis are prone to invasive bacterial infections like methicillin-resistant Staphylococcus aureus (MRSA) especially in the presence of central venous catheters or arteriovenous grafts. However, intracranial abscess formation due to MRSA is rare. Here, we present a case of MRSA brain abscess with an atypical clinical presentation in the absence of traditional risk factors.Intracranial abscesses are uncommon, serious, and life-threatening infections. A Brain abscess is caused by inflammation and collection of infected material, coming from local or remote infectious sources. Patients with chronic kidney disease on dialysis are prone to invasive bacterial infections like methicillin-resistant staphylococcus aureus (MRSA) especially in the presence of central venous catheters or arterio-venous grafts. However intracranial abscess formation due to MRSA is rare. Here we present a case of MRSA brain abscess with an atypical clinical presentation in the absence of traditional risk factors. A 46-year-old male with chronic kidney disease (CKD) secondary to chronic glomerulonephritis, on haemodialysis for 4 years through a left brachio-cephalic AVF developed an episode of generalised tonic-clonic seizures lasting 2 min during his scheduled dialysis session. He reported no complaints before entry to the dialysis. On clinical examination, he was drowsy with the absence of any focal motor deficits. His blood pressure was recorded to be 200/120 mm Hg. He was managed in the intensive care unit with mechanical ventilation, intravenous nitroglycerine for blood pressure control, levetiracetam for seizures and empirical vancomycin. Radiological evaluation showed a brain abscess in the midline involving bosth basi-frontal lobes. After medical optimization, the abscess was drained surgically, and the pus cultured. As culture grew Methicillin Resistant Staphylococcus aureus, he was treated with intravenous vancomycin for 6 weeks. On follow up, the abscess had resolved and the patient recovered without any neurological deficits.

Mitochondrial Reactive Oxygen Species and Their Contribution in Chronic Kidney Disease Progression Through Oxidative Stress

Mitochondria are known to generate approximately 90% of cellular reactive oxygen species (ROS). The imbalance between mitochondrial reactive oxygen species (mtROS) production and removal due to overproduction of ROS and/or decreased antioxidants defense activity results in oxidative stress (OS), which leads to oxidative damage that affects several cellular components such as lipids, DNA, and proteins. Since the kidney is a highly energetic organ, it is more vulnerable to damage caused by OS and thus its contribution to the development and progression of chronic kidney disease (CKD). This article aims to review the contribution of mtROS and OS to CKD progression and kidney function deterioration.

Narrative Review of Hyperferritinemia, Iron Deficiency, and the Challenges of Managing Anemia in Aboriginal and Torres Strait Islander Australians With CKD

Aboriginal and Torres Strait Islander Australians (Indigenous Australians) suffer some of the highest rates of chronic kidney disease (CKD) in the world. Among Indigenous Australians in remote areas of the Northern Territory, prevalence rates for renal replacement therapy (RRT) are up to 30 times higher than national prevalence. Anemia among patients with CKD is a common complication. Iron deficiency is one of the major causes. Iron deficiency is also one of the key causes of poor response to the mainstay of anemia therapy with erythropoiesis-stimulating agents (ESAs). Therefore, the effective management of anemia in people with CKD is largely dependent on effective identification and correction of iron deficiency. The current identification of iron deficiency in routine clinical practice is dependent on 2 surrogate markers of iron status: serum ferritin concentration and transferrin saturation (TSAT). However, questions exist regarding the use of serum ferritin concentration in people with CKD because it is an acute-phase reactant that can be raised in the context of acute and chronic inflammation. Serum ferritin concentration among Indigenous Australians receiving RRT is often markedly elevated and falls outside reference ranges within most national and international guidelines for iron therapy for people with CKD. This review explores published data on the challenges of managing anemia in Indigenous people with CKD and the need for future research on the efficacy and safety of treatment of anemia of CKD in patients with high ferritin and evidence iron deficiency.

Complications of Kidney Disease

Understanding the physiology of the kidney and the pathophysiology of common complications of chronic kidney disease (CKD) is essential. The rise of CKD across the United States demands that nurses be prepared to care for these patients. Cardiovascular complications, anemia, and bone formation issues are the most common complications. Approximately 30 million people (15% of adults) are reported to have CKD. By 2020 there will be a 14.4% increase in the prevalence of CKD, and by 2030, the increase will be up by 16.7%. Nurses are integral to providing care that can slow or halt the progression of CKD.

Mineral bone disease in maintenance hemodialysis patients: Association with morbidity and mortality

There is a paucity of data on mineral bone disease in maintenance hemodialysis (MHD) patients from India. This retrospective analysis was undertaken on 858 (males: 599; females: 259) patients from two medical centers on MHD from 1998 to 2010. Age, gender, months on dialysis, hours per session of dialysis, hemoglobin, serum calcium, inorganic phosphorus, intact parathyroid hormone (iPTH), urine output, erythropoietin dosage per week, blood sugar, blood pressure, urea reduction rate, gain in fluid and fluid removed per session, serum albumin, alkaline phosphatase, vitamin D level, supplemental vitamin D and use of phosphate binder for therapy were documented. Overall, 191 patients died (22%) during the observation period. There was an 86% patient survival rate at 1 year on dialysis and an overall predicted 3-year survival rate of 78%. A relatively higher iPTH (P = 0.012), a need for vitamin D supplementation (P = 0.003), less hours on dialysis per session (P = 0.046) and a non-vegetarian diet (P = 0.022) were significantly associated with mortality.

Pulmonary complications of renal disorders

To manage patients with diseases of the lungs and the kidneys, one must first understand the relationship between respiratory and renal function. In treating acute renal failure (ARF), the clinician often must contend with respiratory manifestations of volume overload and metabolic acidosis. Mechanical ventilation in patients with renal failure (RF) can be challenging, particularly with lung protective ventilation and weaning. Patients with chronic renal failure (CRF) experience several respiratory complications. Hypoxaemia during dialysis is now understood to be a predictable effect of the loss of CO(2) into the dialysate. Critical illness of any primary cause predisposes patients not only to acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) but also to the development of ARF. Meanwhile, the potential for ventilator-induced renal injury has increasingly become the subject of active investigation.

Identification and management of chronic kidney disease complications by internal medicine residents: a national survey

Many patients with chronic kidney disease (CKD) receive care from primary care physicians. Identification and management of CKD complications in primary care is suboptimal. It is not known if current residency curriculum adequately prepares a future internist in this aspect of CKD care. We performed an online questionnaire survey of internal medicine residents in the United States to determine knowledge of CKD complications and their management. Four hundred seventy-nine residents completed the survey with postgraduate year (PGY) distribution 166 PGY1, 187 PGY2, and 126 PGY3. Most of the residents correctly recognized anemia (91%) and bone disease (82%) as complications at estimated glomerular filtration rate less than 60 mL/min/1.73 m; however, only half of the residents identified coronary artery disease (54%) as a CKD complication. For a patient with estimated glomerular filtration rate less than 60 mL/min/1.73 m, two thirds of the residents would workup for anemia (62%), whereas half of them would check for mineral and bone disorder (56%). With regard to anemia of CKD, less than half of the residents knew the CKD goal hemoglobin level of 11 to 12 g/dL (44%); most would supplement iron stores (86%), whereas fewer would consider nephrology referral (28%). For mineral and bone disorders, many residents would recommend dietary phosphorus restriction (68%) and check 25-hydroxyvitamin D (62%); fewer residents would start 1,25-dihydroxyvitamin D (40%) or refer to the nephrologist (45%). Residents chose to discontinue angiotensin-converting enzyme inhibitor for medication-related complication of greater than 50% decline in estimated glomerular filtration rate (68%) and potassium greater than 5.5 mEq/L (93%). Mean performance score improved with increasing PGY (PGY1 59.4% ± 17.6%, PGY2 63.6% ± 15.6%, and PGY3 66.2% ± 16.5%; P = 0.002). Our study identified specific gaps in knowledge of CKD complications and management among internal medicine residents. Educational efforts such as instruction on use of CKD clinical practice guidelines may help raise awareness of CKD complications, benefits of early intervention, and improve CKD management.

Associations between changes in hemoglobin and administered erythropoiesis-stimulating agent and survival in hemodialysis patients

Although treating anemia of chronic kidney disease by erythropoiesis-stimulating agents (ESA) may improve survival, most studies have examined associations between baseline hemoglobin values and survival and ignored variations in clinical and laboratory measures over time. It is not clear whether longitudinal changes in hemoglobin or administered ESA have meaningful associations with survival after adjustment for time-varying confounders. With the use of time-dependent Cox regression models, longitudinal associations were examined between survival and quarterly (13-wk averaged) hemoglobin values and administered ESA dose in a 2-yr (July 2001 to June 2003) cohort of 58,058 maintenance hemodialysis patients from a large dialysis organization (DaVita) in the United States. After time-dependent and multivariate adjustment for case mix, quarterly varying administered intravenous iron and ESA doses, iron markers, and nutritional status, hemoglobin levels between 12 and 13 g/dl were associated with the greatest survival. Among prevalent patients, the lower range of the recommended Kidney Disease Quality Outcomes Initiative hemoglobin target (11 to 11.5 g/dl) was associated with a higher death risk compared with the 11.5- to 12-g/dl range. A decrease or increase in hemoglobin over time was associated with higher or lower death risk, respectively, independent of baseline hemoglobin. Administration of any dose of ESA was associated with better survival, whereas among those who received ESA, requiring higher doses were surrogates of higher death risk. In this observational study, greater survival was associated with a baseline hemoglobin between 12 and 13 g/dl, treatment with ESA, and rising hemoglobin. Falling hemoglobin and requiring higher ESA doses were associated with decreased survival. Randomized clinical trials are required to examine these associations.

Survival predictability of time-varying indicators of bone disease in maintenance hemodialysis patients

Although renal osteodystrophy and vitamin D analogs may be related to survival in maintenance hemodialysis (MHD) patients, most studies have examined associations between baseline values and survival without accounting for variations in clinical and laboratory measures over time. We examined associations between survival and quarterly laboratory values and administered paricalcitol in a 2-year (July 2001-June 2003) cohort of 58,058 MHD patients from all DaVita dialysis clinics in USA using both time-dependent Cox models with repeated measures and fixed-covariate Cox models with only baseline values. Whereas hypercalcemia and hyperphosphatemia were robust predictors of higher death risk in all models, the association between serum calcium and mortality was different in time-varying models. Changes in baseline calcium and phosphorus values beyond the Kidney Disease Outcome Quality Initiative recommended targets were associated with increased mortality. Associations between high serum parathyroid hormone and increased death risk were masked by case-mix characteristics of MHD patients. Time-varying serum alkaline phosphatase had an incremental association with mortality. Administration of any dose of paricalcitol was associated with improved survival in time-varying models. Controlling for nutritional markers may introduce overadjustment bias owing to their strong collinearity with osteodystrophy surrogates. Whereas both time-dependent and fixed-covariate Cox models result in similar associations between osteodystrophy indicators and survival, subtle but potentially clinically relevant differences between the two models exist, probably because fixed models do not account for variations of osteodystrophy indices and changes in medication dose over time.

Association of anemia with outcomes in men with moderate and severe chronic kidney disease

Anemia is a common complication of chronic kidney disease (CKD), but the outcomes associated with lower hemoglobin (Hgb) levels in patients with CKD not yet on dialysis are not well characterized. Analyses exploring outcomes associated with a single baseline Hgb value also do not account for the longitudinal variation of this measure. After collecting all Hgb measurements (N=17 194, median (range): 12 (1-168)) over a median follow-up period of 2.1 years in a historical prospective cohort of 853 male US veterans with CKD Stages 3-5 not yet on dialysis, we examined the association of time-averaged Hgb levels with predialysis all-cause mortality, end-stage renal disease (ESRD), and a composite end point of both. Kaplan-Meier survival analysis and Cox models adjusted for age, race, body mass index, smoking status, blood pressure, diabetes mellitus, cardiovascular disease, categories of estimated glomerular filtration rate, serum concentrations of albumin and cholesterol, and proteinuria were examined. Lower time-averaged Hgb was associated with significantly higher hazard of the composite end point (hazard ratio (95% confidence interval) in the adjusted model for time-averaged Hgb of <110, 111-120 and 121-130, compared to >130 g/l: 2.57 (1.85-3.58), 1.97 (1.45-2.66), 1.19 (0.86-1.63), P(trend)<0.001). Lower time-averaged Hgb was associated with both significantly higher pre-dialysis mortality and higher risk of ESRD, when analyzed separately. Anemia (especially time-averaged Hgb <120 g/l) is associated with both higher mortality and increased risk of ESRD in male patients with CKD not yet on dialysis.

Time-dependent associations between iron and mortality in hemodialysis patients

The independent association between the indices of iron stores or administered intravenous iron, both of which vary over time, and survival in patients who are on maintenance hemodialysis (MHD) is not clear. It was hypothesized that the observed associations between moderately high levels of three iron markers (serum ferritin, iron, and iron saturation ratio) or administered intravenous iron and all-cause and cardiovascular death is due to the time-varying confounding effect of malnutrition-inflammation-cachexia syndrome (MICS). Time-dependent Cox regression models were examined using prospectively collected data of the 2-yr (July 2001 to June 2003) historical cohort of 58,058 MHD patients from virtually all DaVita dialysis clinics in the United States. After time-dependent and multivariate adjustment for case mix, administered intravenous iron and erythropoietin doses, and available surrogates of MICS, serum ferritin levels between 200 and 1200 ng/ml (reference 100 to 199 ng/ml), serum iron levels between 60 and 120 microg/ml (reference 50 to 59 microg/ml), and iron saturation ratio between 30 and 50% (reference 45 to 50%) were associated with the lowest all-cause and cardiovascular death risks. Compared with those who did not receive intravenous iron, administered intravenous iron up to 400 mg/mo was associated with improved survival, whereas doses >400 mg/mo tended to be associated with higher death rates. The association between serum ferritin levels >800 ng/ml and mortality in MHD patients seems to be due mostly to the confounding effects of MICS. For ascertaining whether the observed associations between moderate doses of administered intravenous iron and improved survival are causal or due to selection bias by indication, clinical trials are warranted.

How to interpret and pursue an abnormal complete blood cell count in adults

A complete blood cell count (CBC) is one of the most common laboratory tests in medicine. For example, at our institution alone, approximately 1800 CBCs are ordered every day, and 10% to 20% of results are reported as abnormal. Therefore, it is in every clinician's interest to have some understanding of the specific test basics as well as a structured action plan when confronted with abnormal CBC results. In this article, we provide practical diagnostic algorithms that address frequently encountered conditions associated with CBC abnormalities including anemia, thrombocytopenia, leukopenia, polycythemia, thrombocytosis, and leukocytosis. The objective is to help the nonhematologist recognize when a subspecialty consultation is reasonable and when it may be circumvented, thus allowing a cost-effective and intellectually rewarding practice.