Anorexia in hemodialysis patients: an update.

Anorexia, defined as the loss of the desire to eat, is relatively common in hemodialysis (HD) patients, occurring in one-third of cases. The pathogenesis is essentially unknown. It has been proposed that uremic toxins as middle molecules, inflammation, altered amino-acid pattern, leptin, ghrelin, and neuropeptide Y are involved. Anorexia reduces oral energy and protein intakes, thus contributing to the development of malnutrition and cachexia. Unquestionably, it contributes to poor quality of life. The clinical relevance of anorexia as an independent prognostic factor in HD patients is a matter of debated issue. The treatment of this debilitating condition is based on a therapeutic strategy which may include daily dialysis sessions and nutritional counseling. Normalization of plasma branched-chain amino acids through branched-chain amino acids supplementation may decrease anorexia and improve energy and protein intake. The role of megestrol acetate as appetite stimulant needs to be validated through adequate randomized trials. Subcutaneous ghrelin administration and melanocortin-receptor antagonists appear promising therapeutic interventions.

Destructive spondyloarthropathy of the cervical spine in long-term hemodialyzed patients: a five-year clinical radiological prospective study.

OBJECTIVE: To describe the radiographic features and progression of cervical spine destructive spondyloarthropathy (DSA) in hemodialyzed patients, and to evaluate the relationship between this disease and patient characteristics, biochemical values, and hemodialysis duration. DESIGN AND PATIENTS: Standard radiographs, and lateral flexion and extension views of the cervical spine, were performed annually for 5 years in 31 hemodialyzed patients who were divided into three groups at the commencement of the study: those showing (I) DSA, (II) vertebral rim erosions (VRE) without DSA, and (III) absence of DSA and VRE. Magnetic resonance (MR) imaging and computed tomography (CT) were performed in seven and two patients respectively. The imaging features were evaluated for the presence and progression of spondyloarthropathy and correlated with clinical and biochemical variables. Statistical analysis was performed using one-way analysis of variance. RESULTS: The duration of hemodialysis appeared to be the main predictive factor (P=0.0003) for DSA, which was found in six patients (19%). DSA was found to correlate with higher levels of beta2-microglobulin (P<0.00001), parathyroid hormone (P<0.05), and alkaline phosphatase (P<0.05). Clinical symptoms were minimal. In two patients, MR imaging revealed changes mimicking spondylodiscitis. In another patient, CT of the craniocervical junction showed bone resorption due to a pseudotumor, and basilar invagination. CONCLUSIONS: DSA of the cervical spine is often clinically silent. Pathogenesis of DSA may be multifactorial but its progression is most influenced by the duration of hemodialysis. On MR imaging, DSA may mimic spondylodiscitis.

Arterial injuries following diagnostic, therapeutic, and accidental arterial cannulation in haemodialysis patients.

BACKGROUND: Incidence of iatrogenic arterial lesions is currently increasing and patients undergoing dialysis represent a group at high risk since they require repeated cannulation of the vascular access and intermittent heparinization during maintenance haemodialysis. CLINICAL REPORTS: Between 1992 and 1995 we treated four vascular lesions (two pseudoaneurysms and two arteriovenous fistulae) with surgery in three patients undergoing dialysis at our centre. No postoperative morbidity and mortality was observed; in all cases surgery was effective. CONCLUSIONS: Although conservative treatment (US guided compression) of arterial lesions shows promising results, in patients undergoing dialysis combined with heparinization it seems less suitable. In these patients, early detection of post-cannulation pseudoaneurysms or arteriovenous fistulae allows surgical treatment, with low morbidity rate and satisfactory long-term outcome.

Foot alterations in the hemodialyzed patient.

On the basis of their experience, the authors refer to complications observable at the foot level in chronic uremic patients in long-term hemodialytic treatment. These complications, termed renal osteodystrophy, are attributed to alterations in the phosphocalcium metabolism and to hyperparathyroidism. From an anatomopathologic viewpoint, they are characterized by alteration in bone tissue (osteomalacia and/or fibrous osteitis) and by soft tissue alterations. Alterations in the foot are the same as those observed in other osteoarticular regions. They consist of bone subperiosteal reabsorption of the phalanges, vascular calcifications, articular and para-articular calcifications, spontaneous disinsertion of the Achilles tendon and peripheral canalicular neuropathies specifically represented by the tarsal tunnel syndrome. Another complication of this pathology is represented by "Calciphylaxis," characterized by calcifications of the middle tunica of arteries and small arteries, by ulcerations and tissue necrosis at the foot level.

Effects of supine versus sitting bedrest upon blood gas tensions, cardiac output, venous admixture and ventilation-perfusion ratio in man after upper abdominal surgery.

The effects of body position (sitting versus supine) on respiratory and haemodynamic patterns were evaluated in nine patients who have undergone upper abdominal surgery. Posture showed no significant influence upon arterial blood gas tensions, while in the sitting position mean central venous oxygen tension lowers and arterial-venous oxygen content difference rises. In seated patients cardiac output was notably reduced. Pulmonary gas exchange analysis, according to Riley's method, showed that the sitting position allows a higher alveolar ventilation-pulmonary capillaries perfusion ratio, as well as a lower degree of venous admixture.