X-linked hypophosphataemia (XLH) is the most frequent cause of hypophosphataemia-associated rickets of genetic origin and is associated with high levels of the phosphaturic hormone fibroblast growth factor 23 (FGF23). In addition to rickets and osteomalacia, patients with XLH have a heavy disease burden with enthesopathies, osteoarthritis, pseudofractures and dental complications, all of which contribute to reduced quality of life. This Consensus Statement presents the outcomes of a working group of the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases, and provides robust clinical evidence on management in XLH, with an emphasis on patients\' experiences and needs. During growth, conventional treatment with phosphate supplements and active vitamin D metabolites (such as calcitriol) improves growth, ameliorates leg deformities and dental manifestations, and reduces pain. The continuation of conventional treatment in symptom-free adults is still debated. A novel therapeutic approach is the monoclonal anti-FGF23 antibody burosumab. Although promising, further studies are required to clarify its long-term efficacy, particularly in adults. Given the diversity of symptoms and complications, an interdisciplinary approach to management is of paramount importance. The focus of treatment should be not only on the physical manifestations and challenges associated with XLH and other FGF23-mediated hypophosphataemia syndromes, but also on the major psychological and social impact of the disease.

OBJECTIVE: Protein-energy wasting (PEW) is a state of metabolic and nutritional derangements in chronic disease states including chronic kidney disease (CKD). Cumulative evidence suggests that PEW, muscle wasting and cachexia are common and strongly associated with mortality in CKD, which is reviewed here.
RESULTS: The malnutrition-inflammation score (KALANTAR Score) is among the comprehensive and outcome-predicting nutritional scoring tools. The association of obesity with poor outcomes is attenuated across more advanced CKD stages and eventually reverses in the form of obesity paradox. Frailty is closely associated with PEW, muscle wasting and cachexia. Muscle loss shows stronger associations with unfavorable outcomes than fat loss. Adequate energy supplementation combined with low-protein diet for the management of CKD may prevent the development of PEW and can improve adherence to low-protein diet, but dietary protein requirement may increase with aging and is higher under dialysis therapy. Phosphorus burden may lead to poor outcomes. The target serum bicarbonate concentration is normal range and at least 23 mEq/l for nondialysis-dependent and dialysis-dependent CKD patients, respectively. A benefit of exercise is suggested but not yet conclusively proven.
CONCLUSIONS: Prevention and treatment of PEW should involve individualized and integrated approaches to modulate identified risk factors and contributing comorbidities.

Protein-energy wasting (PEW), a term proposed by the International Society of Renal Nutrition and Metabolism (ISRNM), refers to the multiple nutritional and catabolic alterations that occur in chronic kidney disease (CKD) and associate with morbidity and mortality. To increase awareness, identify research needs, and provide the basis for future work to understand therapies and consequences of PEW, ISRNM provides this consensus statement of current knowledge on the etiology of PEW syndrome in CKD. Although insufficient food intake (true undernutrition) due to poor appetite and dietary restrictions contribute, other highly prevalent factors are required for the full syndrome to develop. These include uremia-induced alterations such as increased energy expenditure, persistent inflammation, acidosis, and multiple endocrine disorders that render a state of hypermetabolism leading to excess catabolism of muscle and fat. In addition, comorbid conditions associated with CKD, poor physical activity, frailty, and the dialysis procedure per se further contribute to PEW.

Undernutrition (wasting) is still frequent in patients infected with the human immunodeficiency virus (HIV), despite recent decreases in the prevalence of undernutrition in western countries (as opposed to developing countries) due to the use of highly active antiretroviral treatment. Undernutrition has been shown to have a negative prognostic effect independently of immunodeficiency and viral load. These guidelines are intended to give evidence-based recommendations for the use of enteral nutrition (EN) by means of oral nutritional supplements (ONS) and tube feeding (TF) in HIV-infected patients. They were developed by an interdisciplinary expert group in accordance with officially accepted standards and is based on all relevant publications since 1985. Nutritional therapy is indicated when significant weight loss (>5% in 3 months) or a significant loss of body cell mass (>5% in 3 months) has occurred, and should be considered when the body mass index (BMI) is <18.5 kg/m(2). If normal food intake including nutritional counselling and optimal use of ONS cannot achieve an adequate nutrient intake, TF with standard formulae is indicated. Due to conflicting results from studies investigating the impact of immune-modulating formulae, these are not generally recommended. The results obtained in HIV patients may be extrapolated to other chronic infectious diseases, in the absence of available data.