BackgroundThe anabolic response to progressive resistance exercise training (PRET) in haemodialysis patients is unclear. This pilot efficacy study aimed to determine whether high-intensity intradialytic PRET could reverse atrophy and consequently improve strength and physical function in haemodialysis patients. A second aim was to compare any anabolic response to that of healthy participants completing the same program.MethodsIn a single blind controlled study, 23 haemodialysis patients and 9 healthy individuals were randomly allocated to PRET or an attention control (SHAM) group. PRET completed high-intensity exercise leg extensions using novel equipment. SHAM completed low-intensity lower body stretching activities using ultra light resistance bands. Exercises were completed thrice weekly for 12 weeks, during dialysis in the haemodialysis patients. Outcomes included knee extensor muscle volume by magnetic resonance imaging, knee extensor strength by isometric dynamometer and lower body tests of physical function. Data were analysed by a per protocol method using between-group comparisons.ResultsPRET elicited a statistically and clinically significant anabolic response in haemodialysis patients (PRET—SHAM, mean difference [95 % CI]: 193[63 to 324] cm3) that was very similar to the response in healthy participants (PRET—SHAM, 169[−41 to 379] cm3). PRET increased strength in both haemodialysis patients and healthy participants. In contrast, PRET only enhanced lower body functional capacity in the healthy participants.ConclusionsIntradialytic PRET elicited a normal anabolic and strength response in haemodialysis patients. The lack of a change in functional capacity was surprising and warrants further investigation.

Unaccustomed strenuous physical exertion in hot environments can result in heat stroke and acute kidney injury (AKI). Both exercise-induced muscle damage and AKI are associated with the release of interleukin-6, but whether muscle damage causes AKI in the heat is unknown. We hypothesized that muscle-damaging exercise, before exercise in the heat, would increase kidney stress. Ten healthy euhydrated men underwent a randomized, crossover trial involving both a 60-min downhill muscle-damaging run (exercise-induced muscle damage; EIMD), and an exercise intensity-matched non-muscle-damaging flat run (CON), in random order separated by 2 wk. Both treatments were followed by heat stress elicited by a 40-min run at 33°C. Urine and blood were sampled at baseline, after treatment, and after subjects ran in the heat. By design, EIMD induced higher plasma creatine kinase and interleukin-6 than CON. EIMD elevated kidney injury biomarkers (e.g., urinary neutrophil gelatinase-associated lipocalin (NGAL) after a run in the heat: EIMD-CON, mean difference [95% CI]: 12 [5, 19] ng/ml) and reduced kidney function (e.g., plasma creatinine after a run in the heat: EIMD-CON, mean difference [95% CI]: 0.2 [0.1, 0.3] mg/dl), where CI is the confidence interval. Plasma interleukin-6 was positively correlated with plasma NGAL (r = 0.9, P = 0.001). Moreover, following EIMD, 5 of 10 participants met AKIN criteria for AKI. Thus for the first time we demonstrate that muscle-damaging exercise before running in the heat results in a greater inflammatory state and kidney stress compared with non-muscle-damaging exercise. Muscle damage should therefore be considered a risk factor for AKI when performing exercise in hot environments.

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Heat strain was increased during endurance exercise in the heat conducted 30 min after and, to a much lesser extent, 24 h after muscle-damaging exercise. These data indicate that EIMD is a likely risk factor for exertional heat illness particularly during exercise heat stress when behavioral thermoregulation cues are ignored.

Aim: We sought to determine if an acute kidney injury biomarker, neutrophil gelatinaseassociated lipocalin (NGAL), would be up-regulated by high-intensity proteinuria-inducing exercise. Methods: A prospective cohort design was utilised. 100 healthy, active adults (mean age 24 ± 4 (SD) years) were screened for post-exercise proteinuria (PeP); 10 PeP positive and 10 PeP negative participants then completed a high-intensity exercise protocol involving an 800 meter sprint. Plasma and urinary NGAL, urinary creatinine, urinary albumin and urine volume were obtained at the following time points: pre-run, immediately post-, 25 minutes, one hour and two hours post-run. Results: Following high-intensity exercise, 64% of participants had urinary NGAL concentrations above the normal range, particularly at 25 minutes post (P = 0.002). However, there was no difference in NGAL response between PeP positive and negative groups and plasma NGAL was decreased, not elevated, following exercise (P = 0.002). In some individuals normalizing urinary NGAL for urinary creatinine attenuated elevations. Urinary NGAL was also negatively correlated with urine volume (r = -0.701, P = 0.005). Conclusion: Proteinuria susceptibility did not influence an acute injury biomarker response to exercise. Nevertheless, urinary NGAL was elevated by exercise, possibly due to increased production by the proximal tubule, increased plasma clearance (given the decrease in plasma NGAL) and/or a concentrating effect of exercise-induced oliguria. Until correct normalisation of urinary biomarkers is determined, NGAL should be interpreted cautiously in exercise and acute kidney injury-induced oliguria. The inter-individual NGAL response to exercise also warrants further investigation.

Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy (TMA) which encompasses hemolytic anemia, thrombocytopenia, and organ impairment. Around 10% of cases are atypical HUS (aHUS), a rare disease with poor outcomes caused by uncontrolled activation of the alternative complement pathway. This case describes a young woman with clinical manifestations compatible with TMA during childhood and adolescence who was formally diagnosed with aHUS at the age of 21. She was managed with intensive plasma exchange and hemodialysis, which failed to improve her severe acute kidney injury and other hematological manifestations of aHUS. This was further compounded by several episodes of flash pulmonary edema and the posterior reversible encephalopathy syndrome (PRES). Treatment with the monoclonal anti-C5 inhibitor, eculizumab, improved all hematological parameters with almost full renal recovery following 3.5 months of dialysis. So far, long-term use of eculizumab (> 11 months) continues to be effective and without complication. Our case illustrates the difficulty but importance of early consideration of aHUS in patients presenting with TMA. More importantly, we highlight that near-normal renal recovery may be attained with eculizumab in adults even after a long dependence on dialysis - an observation that has not been reported in the literature so far.

Pheochromocytoma is rare in pregnancy, with an estimated incidence of 0.007%. Diagnosis is difficult owing to the variety of presentations and nonspecific symptoms. Nevertheless, unsuspected disease accounts for a significant proportion of morbidity and mortality. Currently, there appears to be no consensus on management with regard to the need for and timing of medical vs. surgical management. In this case report, we describe two patients who underwent different modes of treatment based on careful consideration of disease-related and nondisease-related factors. We emphasise that good outcomes can be achieved through individualized management within the context of a multidisciplinary team, involving close collaboration among physicians, surgeons, obstetricians, and anesthetists. We also illustrate the importance of genetic testing in all patients with pheochromocytoma in pregnancy, especially with the emergence of new predisposing genes (succinate dehydrogenase B and D) and the recognition that germline mutations in these and more established genes (VHL and RET) account for over a quarter of all apparently sporadic cases.

Duodenal varices are a rare complication of portal hypertension secondary to liver cirrhosis. Compared to oesophageal varices, they bleed less often but are also more difficult to diagnose and treat. There is no established treatment for bleeding duodenal varices and different treatment strategies have been employed with variable results. The authors present a case of 52-year-old male who was admitted with melaena. Upper gastrointestinal endoscopy was performed which identified bleeding varices in the second part of duodenum. The varices were injected with cyanoacrylate and the outcome was favourable. Subsequent endoscopies showed complete resolution of the varices. The authors conclude that cyanoacrylate injection is an effective first-line treatment for bleeding duodenal varices.