Plasma and Muscle Carnitine Levels in Haemodialysis Patients with Morphological-Ultrastructural Examination of Muscle Samples

Abstract

The present study investigates 14 patients on intermittent haemodialysis. Pre-dialysis blood and muscle samples were taken for determining plasma free- and acetylcarnitine levels. The tissue fragments were used for light and electron microscopy studies. Our results support the findings of other investigators that patients on haemodialysis generally display decreased free- and acetylcarnitine levels both in plasma and skeletal muscle when compared with control values. Muscle carnitine deficiency was apparently more severe in the longer-term haemodialysis patients. Moreover, a significant correlation (p < 0.05) between plasma and muscle free-carnitine values was found. Morphologically no pathological alterations were observed in the muscle fibres in 13 of the patients. Light and electron microscopic studies of the muscle fibre of the 14th patient showed a typical nemaline myopathy with rod bodies in the cytoplasm. The muscle free-carnitine concentration in this patient was among the lowest of the group.

Avaliação das pressões respiratórias máximas em pacientes renais crônicos nos momentos pré e pós-hemodiálise

“…Muscle weakness is a complication of CKD 7,24,25 and muscle mass loss is the most significant predictor of mortality in HD patients. 26 The cause is unknown, but has been related to carnitine deficiency 25 , vitamin D deficiency 27 , excessive amount of parathyroid hormone 28 , aluminum toxicity 29 , and other uremic toxins.…”

“…26 The cause is unknown, but has been related to carnitine deficiency 25 , vitamin D deficiency 27 , excessive amount of parathyroid hormone 28 , aluminum toxicity 29 , and other uremic toxins. 30,31 Uremia causes atrophy of type II muscle fibers 29 and alterations in myofibrillar ATPase, with an important reduction in energy use by the muscle, in creatine phosphorylation, and its contractility.…”

31P-magnetic resonance spectroscopy assessment of subnormal oxidative metabolism in skeletal muscle of renal failure patients.

“…Deltoid, gastrocnemius, rectus femoris, and quadriceps femoris muscles have shown reduced oxidative enzyme activity, increased type II fiber percentage, fiber atrophy, low capillary density, mitochondrial inclusions, and low carnitine content (34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44); also, pallor ofrectus femoris biopsy specimens implies low myoglobin content (personal observation of G. E. Moore). Each of these abnormalities would favor oxygen-independent energy metabolism (45)(46)(47)(48).…”

A nemaline myopathy mutation in α-tropomyosin causes defective regulation of striated muscle force production

“…This hypothesis is supported clinically, as many patients with NM show clinical phenotypes (e.g., hypotonia) before nemaline rods are visible, and rods are seen only when a subsequent, second muscle biopsy is analyzed (1). In addition, other unrelated conditions, such as HIV infection and hemodialysis in the absence of mutant sarcomeric protein expression, have been shown to induce nemaline rods in muscle fibers (26,27). Further, nemaline rods are also seen in combination with other types of skeletal muscle myopathies such as central core disease and mitochondrial myopathies (1).…”