Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023380 (lethargy)
 5,697 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The D(-) isomer of lactic acid appears to cause a form of metabolic encephalopathy experienced by patients who have had jejunoileal bypass for morbid obesity. However, analysis for D(-)-lactate is not routinely available in clinical or reference laboratories. We describe an enzymic centrifugal-analyzer assay for D(-)-lactate in plasma or serum, with use of D(-)-lactate dehydrogenase. The method involves two-point kinetic calibration and preincubation of specimen and NAD+, thus eliminating the need for specimen-blanking or protein-precipitating pretreatment. This rapid, accurate, and precise assay should be helpful in evaluating patients with "short-bowel syndrome" who display confusion, lethargy, ataxia, or other central nervous-system disturbances that may be ascribable to D(-)-lactic acidosis.
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PMID:Kinetic enzymic assay for D(-)-lactate, with use of a centrifugal analyzer. 661 31

Although disorders of thyroid function may cause a wide range of muscle disturbances, an overt myopathy has been rarely reported as an isolated clinical presentation of hypothyroidism. We observed 10 patients (5 males and 5 females) who had been referred to the department of neurology because of muscular fatigability, myalgia, cramps, or proximal weakness. Laboratory investigation showed that all patients had hypothyroidism due to Hashimoto's thyroiditis (atrophic variant in 9/10). Classic symptoms/signs of hypothyroidism such as lethargy, constipation, cold intolerance, myxedematous facies, and/or bradycardia were absent, as assessed independently by the three coauthoring thyroidologists. Muscular complaints improved greatly and then disappeared after substitutive levothyroxine treatment. Muscle biopsy revealed nonspecific changes. Nicotinamide adenine dinucleotide reductase (NADH-TR)-hyporeactive cores were present in two patients (10% and 90% of type 1 fibers). On electron microscopy, the core areas showed disorganized myofibrils, Z-band streaming, rod formation, and paucity of mitochondria and glycogen granules. Desmin intermediate filaments were overexpressed only in some cores. The similarity of the pattern of desmin expression between hypothyroid cores and target lesions of denervated fibers supports the hypothesis that, at least in some of our patients, myopathy was the result of an impaired nerve-mediated action of thyroid hormones on skeletal muscle. Our observations suggest that an isolated myopathy as the sole manifestation of hypothyroidism is not a rare event. We postulate that our cases may constitute a peculiar subgroup of Hashimoto's thyroiditis patients: (1) the strikingly abnormal F/M ratio of 1:1; (2) the relatively younger age; (3) the rarity of the goitrous variant; (4) the unusual finding of antithyroglobulin (Tg-Ab) > antithyroid peroxidase (TPO-Ab). Thorough evaluation of thyroid function is appropriate in patients with myopathy of uncertain origin.
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PMID:Myopathy as the persistently isolated symptomatology of primary autoimmune hypothyroidism. 984 19

Metabolism is a tightly regulated sequence of events, supported by key reactions between enzymes and enzyme-specific substrates. These reactions have the potential to produce metabolic side products that can have deleterious effects to further key metabolic reactions. The nicotinamide repair system consists of two partner enzymes, NAD(P)HX epimerase (NAXE) and NAD(P)HX dehydratase (NAXD). These enzymes regulate the levels of metabolic side products. Here we present a case of an 11-month old child who presented to our paediatric department with pyrexia, lethargy and multiple cutaneous lesions on the background of NAXD deficiency, a lethal neurometabolic disorder of early childhood. Despite early intervention with intravenous antibiotics, the patient failed to improve and subsequently passed away. The skin lesions were thought to be a consequence of systemic disease rather than a propagator of infection. Clinicians should be aware of this incredibly rare metabolic disease, its potential to cause widespread systemic dysfunction and the developing avenues for management.
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PMID:Cutaneous manifestations of NAXD deficiency - A case report. 3322 89