Myoglobin clearance by continuous venous-venous haemofiltration in rhabdomyolysis with acute kidney injury: a case series

Kidney replacement and conservative therapies in rhabdomyolysis: a retrospective analysis

BACKGROUND

Toxic renal effects of myoglobin following rhabdomyolysis can cause acute kidney injury (AKI) with the necessity of kidney replacement therapy (KRT). Fast elimination of myoglobin seems notable to save kidney function and intensify kidney repair. Clinical data regarding efficacy of KRT in critical care patients with rhabdomyolysis and AKI are limited. This retrospective analysis aimed to identify differences between conservative therapy and different modalities of KRT regarding myoglobin elimination and clinical outcome.

METHODS

This systematic, retrospective, single-center study analyzed 328 critical care patients with rhabdomyolysis (myoglobin > 1000 µg/l). Median reduction rate of myoglobin after starting KRT was calculated and compared for different modalities. Multivariate logistic regression models were established to identify potential confounder on hospital mortality. Filter lifetime of the various extracorporeal circuits was analyzed by Kaplan-Meier curves.

RESULTS

From 328 included patients 171 required KRT. Health condition at admission of this group was more critical compared to patient with conservative therapy. Myoglobin reduction rate did not differ between the groups (KRT 49% [30.8%; 72.2%] vs. conservative treatment (CT) 61% [38.5%; 73.5%]; p = 0.082). Comparison between various extracorporeal procedures concerning mortality showed no significant differences. Hospital mortality was 55.6% among patients with KRT and 18.5% with CT (p < 0.001). Multivariate logistic regression model identified requirement for KRT (OR: 2.163; CI: 1.061-4.407); p = 0.034) and the SOFA Score (OR: 1.111; CI: 1.004-1.228; p = 0.041) as independent predictive factors for hospital mortality. When comparing specific KRT using multivariate regression, no benefit was demonstrated for any treatment modality. Life span of the extracorporeal circuit was shorter with CVVH compared to that of others (log-Rank p = 0.017).

CONCLUSIONS

This study emphasizes that AKI requiring KRT following rhabdomyolysis is accompanied by high mortality rate. Differences in myoglobin reduction rate between various KRTs could not be confirmed, but CVVH was associated with reduced filter lifetime compared to other KRTs, which enable myoglobin elimination, too.

Tissue Perfusion and Diffusion and Cellular Respiration: Transport and Utilization of Oxygen

This article provides an overview of the journey of inspired oxygen after its uptake across the alveolar-capillary interface, and the interplay among tissue perfusion, diffusion, and cellular respiration in the transport and utilization of oxygen. The critical interactions between oxygen and its facilitative carriers (hemoglobin in red blood cells and myoglobin in muscle cells), and with other respiratory and vasoactive molecules (carbon dioxide, nitric oxide, and carbon monoxide), are emphasized to illustrate how this versatile system dynamically optimizes regional convective transport and diffusive gas exchange. The rates of reciprocal gas exchange in the lung and the periphery must be well-matched and sufficient for meeting the range of energy demands from rest to maximal stress but not excessive as to become toxic. The mobile red blood cells play a vital role in matching tissue perfusion and gas exchange by dynamically regulating the controlled uptake of oxygen and communicating regional metabolic signals across different organs. Intracellular oxygen diffusion and facilitation via myoglobin into the mitochondria, and utilization via electron transport chain and oxidative phosphorylation, are summarized. Physiological and pathophysiological adaptations are briefly described. Dysfunction of any component across this integrated system affects all other components and elicits corresponding structural and functional adaptation aimed at matching the capacities across the entire system and restoring equilibrium under normal and pathological conditions.

Progress in the Diagnostic and Predictive Evaluation of Crush Syndrome

Crush syndrome (CS), also known as traumatic rhabdomyolysis, is a syndrome with a wide clinical spectrum; it is caused by external compression, which often occurs in earthquakes, wars, and traffic accidents, especially in large-scale disasters. Crush syndrome is the second leading cause of death after direct trauma in earthquakes. A series of clinical complications caused by crush syndrome, including hyperkalemia, myoglobinuria, and, in particular, acute kidney injury (AKI), is the main cause of death in crush syndrome. The early diagnosis of crush syndrome, the correct evaluation of its severity, and accurate predictions of a poor prognosis can provide personalized suggestions for rescuers to carry out early treatments and reduce mortality. This review summarizes various methods for the diagnostic and predictive evaluation of crush syndrome, including urine dipstick tests for a large number of victims, traditional and emerging biomarkers, imaging-assisted diagnostic methods, and developed evaluation models, with the aim of providing materials for scholars in this research field.

The effect of cytosorb® application on kidney recovery in critically ill patients with severe rhabdomyolysis: a propensity score matching analysis

Severe rhabdomyolysis frequently results in acute kidney injury (AKI) due to myoglobin accumulation with the need of kidney replacement therapy (KRT). The present study investigated whether the application of Cytosorb® (CS) led to an increased rate of kidney recovery in patients with KRT due to severe rhabdomyolysis. Adult patients with a myoglobin-concentration >10,000 ng/ml and KRT were included from 2014 to 2021. Exclusion criteria were chronic kidney disease and CS-treatment before study inclusion. Groups 1 and 2 were defined as KRT with and without CS, respectively. The primary outcome parameter was independence from KRT after 30 days. Propensity score (PS) matching was performed (predictors: myoglobin, SAPS-II, and age), and the chi2-test was used. 35 pairings could be matched (mean age: 57 vs. 56 years; mean myoglobin: 27,218 vs. 26,872 ng/ml; mean SAPS-II: 77 vs. 76). The probability of kidney recovery was significantly (p = .04) higher in group 1 (31.4 vs. 11.4%, mean difference: 20.0%, odds ratio (OR): 3.6). Considering patients who survived 30 days, kidney recovery was also significantly (p = .03) higher in patients treated with CS (61.1 vs. 23.5%, mean difference: 37.6%, OR: 5.1). In conclusion, the use of CS might positively affect renal recovery in patients with severe rhabdomyolysis. A prospective randomized controlled trial is needed to confirm this hypothesis.

Therapeutic Plasma Exchange in Severe Rhabdomyolysis: A Case-Control Study

INTRODUCTION

 Rhabdomyolysis is a serious condition that can cause acute kidney injury (AKI), compartment syndrome, severe metabolic and electrolyte derangement leading to arrhythmias, and even death. Total plasma exchange (TPE) has been used as a treatment modality to clear myoglobin, but the evidence is limited. In this study, we aim to investigate the use of TPE in critically ill rhabdomyolysis patients.

METHODS

 We retrospectively chart reviewed adult patients admitted to the intensive care unit (ICU) with a diagnosis of rhabdomyolysis between 2012 and 2021. We dichotomized patients into two groups based on whether TPE was used or not in addition to standard care. PRISMA machines with TPE2000 filters and either 5% albumin or fresh frozen plasma were used in the TPE group.

RESULTS

 The patients' age ranged from 23 years to 87 years (mean 49.4, SD 18.1), and 51% were male. Initial creatinine ranged from 0.6 to 16mg/dL (mean 3.4, SD 2.7), creatinine phosphokinase (CPK) from 403-93,232 U/L, and myoglobin from 934 to >20,000. The Sequential Organ Failure Assessment (SOFA)scores on admission ranged from 6 to 17 (mean 7.23, SD 3.40). Overall, 28.78% (N=19) of the patients received therapeutic plasma exchange. The overall mortality in our study was 31.9%, with the length of ICU stay ranging from 1-25 days (mean 7.10, SD 5.91) among survivors. Older age and the presence of shock were predictive of mortality in univariate and multivariate analyses. There was no statistically significant association in mortality between the TPE and non-TPE groups (36.84% in TPE vs. 36.17% in the non-TPE group, OR 0.7209, p=0.959). Only two patients in the non-TPE group developed CKD/ESRD on long-term follow-up.

CONCLUSION

Our study showed that TPE administration in critically ill patients with rhabdomyolysis did not improve mortality or length of ICU stay. Further studies are required to elucidate its indication and effect on long-term renal outcomes.

Earlier continuous renal replacement therapy is associated with reduced mortality in rhabdomyolysis patients

Background

Continuous renal replacement therapy (CRRT) is commonly employed for rhabdomyolysis (RM) patients. However, the optimal initiation timing of CRRT and prognostic factors were not well evaluated for patients with RM. We aimed to investigate the efficacy of CRRT timing on mortality and the risk factors for death in RM patients who received CRRT.

Methods

RM patients who received CRRT between 1 May 2010 and 31 May 2021 in our center were retrospectively included. Univariate and multivariate logistic analyses were performed to identify the risk factors for primary outcome (90-day mortality).

Results

A total of 134 patients were included in our study. The 90-day mortality rate was 38.06%. The median time from CRRT initiation to peak CK occurrence was 4.8 h (IQR −16, 14), 67 patients received CRRT before 4.8 h after peak CK occurrence (early CRRT), and 67 patients received CRRT beyond 4.8 h after peak CK occurrence (late CRRT). Multivariate logistic regression analysis showed that the time from CRRT initiation to the peak CK (per 1 h, OR 1.026, 95% CI 1.004–1.049, p = 0.023), late CRRT (OR 3.082, 95% CI 1.072–8.859, p = 0.037), elevated serum cardiac troponin I (cTnI) (per 1 ng/mL, OR 1.218, 95% CI 1.011–1.468, p = 0.038), older age (per 1 year, OR 1.042, 95% CI 1.003–1.081, p = 0.032), and need of mechanical ventilation support (OR 4.632, 95% CI 1.292–16.61, p = 0.019) were independent risk factors for 90-day mortality.

Conclusions

Earlier CRRT initiation before 4.8 h after peak CK occurrence was associated with lower 90-day patient mortality.

Serum creatine kinase levels are not associated with an increased need for continuous renal replacement therapy in patients with acute kidney injury following rhabdomyolysis

Severe rhabdomyolysis can lead to acute kidney injury (AKI). Previous studies have reported a benefit from continuous renal replacement therapy (CRRT) for rhabdomyolysis-associated AKI. Here, we investigated the potential for serum creatine kinase (CK) levels to be used as a marker for CRRT termination in patients with AKI following rhabdomyolysis. We compared different CK levels in patients after CRRT termination and observed their clinical outcomes. We retrospectively collected 86 cases with confirmed rhabdomyolysis-associated AKI, who were receiving CRRT in Tongji Hospital. Patients’ renal functions were assessed within 24 h of intermission, patients with urine output ≥ 1,000 mL and serum creatinine ≤ 265 umol/L were considered for CRRT termination. After termination, 33 patients with a CK > 5,000 U/L were included in an experimental group, and 53 patients with a CK < 5,000 U/L were included in a control group. Clinical outcomes were compared between the two groups. Higher CK levels, as well as worse renal functions, predicted the necessity of CRRT. After CRRT termination, the in-hospital mortality (p = 0.389) and Multiple Organ Dysfunction Syndrome (MODS) incidence (p = 0.064) were similar between the two groups, while the experimental group showed a significantly shorter in-hospital length of stay (p = 0.026) and Intensive Care Unit (ICU) length of stay (p = 0.038). CRRT termination may be independent of CK levels for patients with rhabdomyolysis-associated AKI, and this is contingent on their renal functions having recovered to an appropriate level.

Pervitin Intoxication with Two-peak Massive Myoglobinemia, Acute Kidney Injury and Marked Procalcitonin Increase Not Associated with Sepsis

Patients intoxicated with methamphetamine-like substances may present with myoglobinuria but rarely require admission. An 18-year-old female was admitted due to intoxication with pervitin, a methamphetamine derivative. She presented with an altered mental status, fever, and increased heart and respiratory rates. Biomarkers showed leukocytosis and markedly increased procalcitonin levels, suggestive of sepsis. However, blood cultures and infectious disease workup were unrevealing. Clinical course was heralded by rhabdomyolysis and myoglobinuria resulting in multi-organ failure including respiratory failure necessitating mechanical ventilation, hemodynamic compromise with need for inotropic support, and an acute renal failure requiring renal replacement therapy. Surprisingly, after a transient improvement, an unexpected second peak of myoglobin was observed on hospital day 5, controlled by intensifying the elimination methods, and administration of dantrolene. Acute kidney injury resolved by hospital day 15, and the patient could be discharged on day 22. While most patients with intoxications are discharged within 24 hours from emergency departments without being admitted, our case report highlights that the organ injury may evolve beyond the usual observation period, traditional renal-replacement therapies may not be sufficient to mitigate myoglobinemia with resulting acute kidney injury, and that procalcitonin may not be a reliable biomarker of infection in the setting of drug-induced rhabdomyolysis.

Successful Treatment of Rhabdomyolysis-Associated Acute Kidney Injury with Haemoadsorption and Continuous Renal Replacement Therapy

We report two children with rhabdomyolysis-associated acute kidney injury who were successfully treated with a haemoadsorption column CytoSorb® in addition to continuous renal replacement therapy (CRRT). A 14-year-old girl with multiorgan failure requiring extracorporeal membrane oxygenation developed rhabdomyolysis due to reperfusion injury. Her creatine kinase (CK) and lactate levels continued to escalate despite high-dose CRRT. A haemoadsorption column was therefore added post-CRRT filter, which brought down the CK level from 264,500 IU/L to 97,436 IU/L after 8 hours of therapy. Another 4-year-old boy with epilepsy and cerebral palsy who was admitted for gastroenteritis with dehydration developed acute kidney injury and rhabdomyolysis with a peak CK level of 946,060 IU/L. He was initially treated with CRRT for 40 hours, which reduced his CK level to 147,580 IU/L. Two sessions of haemoadsorption were then performed in addition to the CRRT, which further lowered his CK level to 32,306 IU/L in 48 hours. Both patients demonstrated enhanced reduction of CK levels when the haemoadsorption column was used in addition to the CRRT, and no specific complication related to the haemoadsorption therapy was reported. Our cases showed that haemoadsorption can be considered as an adjunctive therapy for children with severe rhabdomyolysis-associated acute kidney injury.

Development and validation of a model for the early prediction of the RRT requirement in patients with rhabdomyolysis

INTRODUCTION

Rhabdomyolysis (RM) is a complex set of clinical syndromes involving the rapid dissolution of skeletal muscles. The early detection of patients who need renal replacement therapy (RRT) is very important and may aid in delivering proper care and optimizing the use of limited resources.

METHODS

Retrospective analyses of the following three databases were performed: the eICU Collaborative Research Database (eICU-CRD), the Medical Information Mart for Intensive Care III (MIMIC-III) database and electronic medical records from the First Medical Centre of the Chinese People's Liberation Army General Hospital (PLAGH). The data from the eICU-CRD and MIMIC-III datasets were merged to form the derivation cohort. The data collected from the Chinese PLAGH were used for external validation. The factors predictive of the need for RRT were selected using a LASSO regression analysis. A logistic regression was selected as the algorithm. The model was built in Python using the ML library scikit-learn. The accuracy of the model was measured by the area under the receiver operating characteristic curve (AUC). R software was used for the LASSO regression analysis, nomogram, concordance index, calibration, and decision and clinical impact curves.

RESULTS

In total, 1259 patients with RM (614 patients from eICU-CRD, 324 patients from the MIMIC-III database and 321 patients from the Chinese PLAGH) were eligible for this analysis. The rate of RRT was 15.0% (92/614) in the eICU-CRD database, 17.6% (57/324) in the MIMIC-III database and 5.6% in the Chinese PLAGH (18/321). After the LASSO regression selection, eight variables were included in the RRT prediction model. The AUC of the model in the training dataset was 0.818 (95% CI 0.78-0.87), the AUC in the test dataset was 0.794 (95% CI 0.72-0.86), and the AUC in the Chinese PLAGH dataset (external validation dataset) was 0.820 (95% CI 0.70-0.86).

CONCLUSIONS

We developed and validated a model for the early prediction of the RRT requirement among patients with RM based on 8 variables commonly measured during the first 24 h after admission. Predicting the need for RRT could help ensure appropriate treatment and facilitate the optimization of the use of medical resources.

Rhabdomyolysis with acute anuria renal failure caused by surgical injection-induced tetanus in an adult

Tetanus is a rapidly progressive infection characterised by painful spasms and muscular rigidity with a series of complications including airway obstruction, respiratory failure, pulmonary infection, heart arrhythmias and acute kidney injury. Rhabdomyolysis with acute anuria renal failure is rarely reported as a complication in tetanus. We present a case of an adult who suffered from rhabdomyolysis combined with acute anuria renal failure caused by surgical injection-induced tetanus. This patient was treated with tetanus immunoglobulin, control of muscle spasm, mechanical ventilation and haemoperfusion plus continuous veno-venous haemofiltration (CVVH). The patient fully recovered and was discharged from hospital 5 weeks after admission. Good bowel preparation is an important prerequisite for preventing tetanus in a haemorrhoids operation. Effective control of muscle spasms with neuromuscular blockers and early administration of haemoperfusion plus CVVH are vital to the treatment of tetanus-induced rhabdomyolysis with acute renal failure.

A Case of Methyl Ethyl Ketone Peroxide Ingestion Complicated by Rhabdomyolysis

Methyl ethyl ketone peroxide (MEKP) is a colorless-to-faintly-yellow liquid that is used as a cross-linking to harden plastics or resins in various industries. It is also an ingredient of paints, varnishes, and paint removers. Because of the high reactivity of MEKP, it is available only as a 40% to 60% solution in dimethyl phthalate or other phthalates. Post-ingestion, the spectrum of complications is vast, ranging from corrosive injury in the oral cavity and gastrointestinal tract to fulminant hepatic toxicity, sepsis, multi-organ failure, and disseminated intravascular coagulation. We report the case of a 40-year-old, self-employed, male worker in a lamination workshop, who presented with accidental ingestion of MEKP from an unlabeled container. He subsequently developed a multitude of complications, most noteworthy being rhabdomyolysis and in turn acute kidney injury. The patient was managed in the intensive care unit with supportive management and hemodialysis sessions; however, the patient succumbed to his illness, despite aggressive measures.

Trauma-associated acute kidney injury

PURPOSE OF REVIEW

A summary of recent research into the epidemiology, cause, management and outcomes of trauma-associated acute kidney injury (AKI). There is an increasing focus on subtypes of AKI to better target clinical management and future research.

RECENT FINDINGS

AKI associated with trauma occurs in 20-24% of patients admitted to ICU. On the basis of creatinine and/or urine output, AKI occurs in the first few days of traumatic illness. Although various associations have been identified, shock and high-volume blood transfusion are the most consistent risks for development of trauma-associated AKI. Short-term outcomes appear worse for patients with AKI, but extent of longer term kidney function recovery remains unknown. Recent research in the general critical care population is beginning to better inform AKI management; however, currently, preventive and supportive strategies remain the mainstay of AKI management after trauma.

SUMMARY

Well-designed, prospective research is required to better understand the phenotype, pathophysiology and recovery trajectory of trauma-associated AKI. Only then can potentially unique therapeutic targets be developed for this common subtype of AKI.

Opioid-related compartment syndrome and associated morbidity

INTRODUCTION

Opioid-related compartment syndrome (ORCS) is an understudied complication related to opioid overdose. We hypothesized that ORCS would be associated with worse clinical outcomes, including higher amputation rates, need for multiple surgical procedures, and rhabdomyolysis on admission, compared with nonopioid-related compartment syndrome (NORCS).

METHODS

We used Current Procedural Terminology codes for fasciotomy as a proxy marker for cases of compartment syndrome treated at 1 health system from January 1, 2016, to December 21, 2018. We excluded patients younger than 18 years, those treated for exertional compartment syndrome, and those who underwent elective fasciotomies. Seventy-four patients met our inclusion criteria. Data reviewed included patient characteristics, cause of compartment syndrome, time until evaluation for compartment syndrome, peak creatinine kinase levels, number of surgical procedures required, duration of hospital stay, and postoperative inpatient morbidity and death. Patients were categorized as having ORCS (n = 8) or NORCS (n = 66). Alpha = .05.

RESULTS

All cases of ORCS occurred in men. Opioid use was the third most common cause of compartment syndrome. Two patients underwent amputation, both in the ORCS group (p <  0.01). The median number of debridements was significantly higher for the ORCS group (median, 4; interquartile range [IQR]: 3-6) than for the NORCS group (median, 3; IQR 2-4) (p =  0.03). Duration of hospital stay was longer for the ORCS group (median, 27 days; IQR 16-38) compared with the NORCS group (median, 9 days; IQR: 5-13) (p <  0.001). Mean (± standard deviation) peak creatinine kinase level was significantly higher in the ORCS group (224,000 ± 225,052 U/L) compared with the NORCS group (7550 ± 32,500) (p <  0.001). The proportion of patients who underwent hemodialysis was higher in the ORCS group (88%) than in the NORCS group (35%) (p <  0.001). All ORCS patients presented >8 h after immobilization in a dependent position.

CONCLUSION

Patients in the ORCS group had delayed presentations and significantly more morbidity compared with patients in the NORCS group.

Acute kidney injury in a Tanzanian boy following multiple bee stings in resource-limited setting: a case report

Bee sting has been identified as among causative agents of nephrotoxic acute tubular necrosis which may lead to acute kidney injury. Bee envenomation has medicinal properties but when a higher dose is inoculated may cause severe anaphylaxis with very poor prognosis. We report a 12-year-old boy with acute kidney injury following multiple bee stings who recovered well after hemodialysis.

Rhabdomyolysis in a Tertiary PICU: A 10-Year Study

OBJECTIVES

Rhabdomyolysis is a disorder of muscle breakdown. The aim of this study was to describe the epidemiology of rhabdomyolysis in children admitted to a PICU and to assess the relationship between peak creatinine kinase and mortality.

DESIGN

Retrospective cohort study in children admitted to the PICU with rhabdomyolysis between January 1, 2005, and December 31, 2014. Demographic, clinical, and outcome data were recorded. Outcomes were analyzed by level of peak creatinine kinase value (0-10,000, 10,001-50,000, > 50,000IU/L). Long-term renal outcomes were reported for PICU survivors.

SETTING

A single-centre academic tertiary PICU.

PATIENTS

Children admitted to the PICU with serum creatinine kinase level greater than 1,000 IU/L.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

There were 182 children with rhabdomyolysis. The median peak creatinine kinase value was 3,583 IU/L (1,554-9,608). The primary diagnostic categories included sepsis, trauma, and cardiac arrest. Mortality for peak creatinine kinase values 0-10,000, 10,001-50,000, and > 50,000 IU/L were 24/138 (17%), 6/28 (21%), and 3/16 (19%), respectively (p = 0.87). Children with a peak creatinine kinase greater than 10,000 IU/L had a longer duration of mechanical ventilation and ICU length of stay than children with peak creatinine kinase less than 10,000. Renal replacement therapy was administered in 29/182 (16%). There was longer duration of mechanical ventilation (273 [141-548] vs. 73 [17-206] hr [p < 0.001]) and ICU length of stay (334 [147-618] vs. 100 [37-232] hr (p < 0.001)] in children receiving renal replacement therapy. Continuous veno-venous hemofiltration was the most common modality 23/29 (79%). Only one child required renal replacement therapy postintensive care stay, and adverse long-term renal outcomes were uncommon.

CONCLUSIONS

In children with rhabdomyolysis requiring intensive care, peak creatinine kinase was not associated with mortality but is associated with greater use of intensive care resources. Chronic kidney disease is an uncommon sequelae of rhabdomyolysis in children requiring intensive care.

High Cut-off Membranes in Acute Kidney Injury and Continuous Renal Replacement Therapy

Innovation in continuous renal replacement therapies (CRRT) utilized to treat acute kidney injury (AKI) and sepsis, has brought new machines and techniques. Part of these new advances are due to the availability of innovative biomaterials and the construction of membranes with larger pores and wide distribution of pore sizes. This includes the creation of a new generation of high cut-off membranes whose utilization in clinical practice is promising for the wide spectrum of solutes that are removed during extracorporeal therapies.

However, the enlargement of pore diameters brings some loss of albumin during treatment and this effect is still under evaluation, since there is a possibility that this is detrimental for the patient. A thorough review of the available clinical literature is reported in this paper with a reappraisal of the potential application of these new technologies.

What Do We Know about Opioids and the Kidney?

Evidence suggests a link between opioid use and kidney disease. This review summarizes the known renal manifestations of opioid use including its role in acute and chronic kidney injury. Both the direct and indirect effects of the drug, and the context which leads to the development of renal failure, are explored. While commonly used safely for pain control and anesthesia in those with kidney disease, the concerns with respect to side effects and toxicity of opioids are addressed. This is especially relevant with the worldwide increase in the use of opioids for medical and recreational use.

Acute kidney injury due to tropical infectious diseases and animal venoms: a tale of 2 continents

South and Southeast Asia and Latin American together comprise 46 countries and are home to approximately 40% of the world population. The sociopolitical and economic heterogeneity, tropical climate, and malady transitions characteristic of the region strongly influence disease behavior and health care delivery. Acute kidney injury epidemiology mirrors these inequalities. In addition to hospital-acquired acute kidney injury in tertiary care centers, these countries face a large preventable burden of community-acquired acute kidney injury secondary to tropical infectious diseases or animal venoms, affecting previously healthy young individuals. This article reviews the epidemiology, clinical picture, prevention, risk factors, and pathophysiology of acute kidney injury associated with tropical diseases (malaria, dengue, leptospirosis, scrub typhus, and yellow fever) and animal venom (snakes, bees, caterpillars, spiders, and scorpions) in tropical regions of Asia and Latin America, and discusses the potential future challenges due to emerging issues.

Automated Fluid Management for Treatment of Rhabdomyolysis

Purpose. Fluid therapy aimed at increasing urine output is a commonly employed strategy to prevent acute kidney injury (AKI) in critically ill patients with rhabdomyolysis. Automated fluid management has the potential to optimise urine output while avoiding fluid accumulation in rhabdomyolysis patients. Methods. In a single centre clinical service evaluation we compared a convenience sample of critically ill adults with rhabdomyolysis treated with automated fluid management using the RenalGuard® device to patients managed with manual fluid adjustment following our standard rhabdomyolysis protocol. Primary outcome was number of hours with urine output >2 mL/kg during first 48 h of therapy. Results. Eight patients treated with RenalGuard were compared to 28 patients treated with manual fluid management. Number of hours of target urine output was greater in the RenalGuard versus the Standard group (176/312 (56.4%) versus 534/1305 (40.9%); p < 0.01). Urine output was significantly higher in the first 24 h in the RenalGuard group (median (IQR) 4033 mL (3682–7363) versus 2913 mL (2263–4188 mL); p < 0.01). Fluid balance, electrolyte, diuretics, and bicarbonate use were comparable between groups. Conclusions. Automated fluid management resulted in a higher urine output more quickly in the treatment of rhabdomyolysis. Further research is needed to analyse the effect of diuresis-matched hydration for the prevention of AKI in rhabdomyolysis.

Continuous renal replacement therapy (CRRT) for rhabdomyolysis

BACKGROUND

Rhabdomyolysis is a condition that is characterised by the breakdown of skeletal muscle tissue and leakage of intracellular myocyte contents into circulating blood. Rhabdomyolysis can lead to acute kidney injury (AKI) and is a potentially life-threatening condition. Studies have indicated that continuous renal replacement therapy (CRRT) may provide benefits for people with rhabdomyolysis by removing potentially damaging myoglobin and stabilising haemodynamic and metabolic status.

OBJECTIVES

We aimed to: i) assess the efficacy of CRRT in removing myoglobin; ii) investigate the influence of CRRT on mortality and kidney-related outcomes; and iii) evaluate the safety of CRRT for the treatment of people with rhabdomyolysis.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 6 January 2014 through contact with the Trials' Search Co-ordinator using search terms relevant to this review. We also searched China National Knowledge Infrastructure (from 1 January 1979 to 16 April 2013) and the Chinese Clinical Trials Register (to 16 April 2013).

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs that investigated clinical outcomes of CRRT for people with rhabdomyolysis were included.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for inclusion and extracted data. We derived risk ratios (RR) for dichotomous data and mean differences (MD) for continuous data with 95% confidence intervals (CI). Methodological risk of bias was assessed using the Cochrane risk of bias tool.

MAIN RESULTS

Of the three included studies (101 participants), one evaluated continuous arteriovenous haemodialysis and two investigated continuous venovenous haemofiltration; all included conventional therapy as control.We found significant decreases in myoglobin in patients among whom CRRT therapy was initiated on days four, eight, and 10 (day 4: MD -11.00 (μg/L), 95% CI -20.65 to -1.35; Day 8: MD -23.00 (μg/L), 95% CI -30.92 to -15.08; day 10: MD -341.87 (μg/L), 95% CI -626.15 to -57.59) compared with those who underwent conventional therapy.Although CRRT was associated with improved serum creatinine, blood urea nitrogen, and potassium levels; reduced duration of the oliguria phase; and was associated with reduced time in hospital, no significant differences were found in mortality rates compared with conventional therapy (RR 0.17, 95% CI 0.02 to 1.37). The included studies did not report on long-term outcomes or prevention of AKI.Overall, we found that study quality was suboptimal: blinding and randomisation allocation were not reported by any of the included studies, leading to the possibility of selection, performance and detection bias.

AUTHORS' CONCLUSIONS

Although CRRT may provide some benefits for people with rhabdomyolysis, the poor methodological quality of the included studies and lack of data relating to clinically important outcomes limited our findings about the effectiveness of CRRT for people with rhabdomyolysis.There was insufficient evidence to discern any likely benefits of CRRT over conventional therapy for people with rhabdomyolysis and prevention of rhabdomyolysis-induced AKI.

Kinetic modelling of haemodialysis removal of myoglobin in rhabdomyolysis patients

An extended two compartment model is proposed to describe the dynamics of myoglobin in rhabdomyolysis patients undergoing dialysis. Before using clinical data to estimate the model's unknown parameters, structural identifiability analysis was performed to determine the parameters uniqueness given certain clinical observations. A Taylor series expansion method was implemented which found that the model was structurally globally/uniquely identifiable for both on- and off-dialysis phases. The fitted model was then used in a predictive capacity showing that the use of Theralite high cut-off (HCO) or HCO 1100 dialyser gave a significant reduction in myoglobin renal exposure compared to standard haemodialysis (HD).

Clearance of myoglobin by high cutoff continuous veno-venous hemodialysis in a patient with rhabdomyolysis: a case report

Continuous veno-venous hemodialysis using high cutoff filters (HCO-CVVHD) is a promising technique, which may be effective to decrease the extremely high level of circulating myoglobin in patients with rhabdomyolysis (RM). Here, we report a patient with RM caused by heat stroke who was successfully treated by HCO-CVVHD. A male patient received HCO-CVVHD with 4 L/h dialysate for 5 days and then pre-dilution continuous veno-venous hemofiltration (CVVH) at a dose of 4 L/h until recovery of renal function. The clearance of myoglobin and albumin at 5 minutes, and at 4, 12, and 24 hours were calculated. The serum myoglobin level decreased from a peak of 25,400 ng/mL on admission to 133 ng/mL at discharge. During HCO-CVVHD, the mean clearances of serum myoglobin at four timepoints were 61.3 (range, 61.0-61.6), 52.3 (38.9-65.8), 47.3 (46.8-47.9), and 43.7 (39.5-48.0) mL/min, respectively, and the mean clearances of albumin were 12.4 (range, 11.8-13.1), 3.1 (2.5-3.8), 1.2 (1.0-1.4), and 0.8 (0.6-1.0) mL/min, respectively. During CVVH, the clearance rates of myoglobin at 5 minutes and 24 hours were 17.0 and 3.8 mL/min, respectively, with a negligible clearance of albumin. HCO-CVVHD can effectively decrease serum myoglobin in patients with RM because of much higher clearance of myoglobin than CVVH. However, attention should be paid to albumin loss during HCO-CVVHD.

Recovery from AKI following multiple wasp stings: a case series

BACKGROUND AND OBJECTIVE

To observe the outcomes of AKI following multiple wasp stings.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Eighty-one patients (mean age ± SD, 45.5 ± 14.7 years; 55 men and 26 women; mean Acute Physiology and Chronic Health Evaluation II score, 16.85 ± 2.78) with AKI following multiple wasp stings between 1997 and 2011 were retrospectively analyzed. Data on their demographic characteristics, initial modalities of renal replacement therapy (RRT), urine output, serum creatinine, bilirubin, myoglobin, and other variables were collected. Renal outcomes included complete recovery of kidney function, CKD, and death. Subgroup analysis was performed according to initial modality of RRT in the first 48 hours, including continuous veno-venous hemofiltration (CVVH), intermittent hemodialysis (IHD), and CVVH plus plasma exchange (PE).

RESULTS

Of the 75 patients available for follow-up, 7 (9.3%) died, and 8 (10.7%, all in the IHD group) developed CKD. The average RRT time was 18.2 ± 8.4 days, and the average kidney function recovery time was 36.0 (29.0, 41.0) days. Subgroup analysis showed no difference in the mortality rates between the CVVH, CVVH + PE, and IHD groups (8.0%, 7.1%, and 11.1%, respectively; P>0.99). The recovery time for kidney function was significantly shorter in the CVVH and CVVH + PE groups than in the IHD group (31.9 ± 8.5 days, 28.6 ± 9.4 days, and 41.6 ± 8.1 days, respectively; P<0.001).

CONCLUSIONS

This is a large case series report on the outcomes of patients with AKI following multiple wasp stings. Most patients survived with complete recovery of their kidney function. Despite the lack of difference in mortality rates, the patients who began RRT with CVVH and CVVH + PE experienced a better and more rapid recovery of kidney function than those initiated with IHD.