Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report on clinicopathological and whole body MRI analyses of the index patient of a large nonconsanguineous German-Ukraine family with homozygous and heterozygous AGL gene mutations at position p.W1327X (c.3980G > A). There are only limited reports on this phenotype with a homozygous genotype. The index patient, a 49-year-old woman presented with hepatomegaly, cardiomyopathy and moderate progressive proximal limb myopathy. Skeletal muscle showed severe vacuolar myopathy with storage of PAS-positive non-membrane-limited glycogen. An increase in glycogen content and completely decrease of debranching enzyme activity was measured in erythrocytes. Mutational analysis of the AGL gene showed a homozygous p.W1327X mutation. In the family, two brothers had been affected by severe infantile onset hepatomegaly and died within their first years of life by fatal liver cirrhosis. Furthermore, another sister severely affected by hepatomegaly, cardiomyopathy and proximal skeletal myopathy died at age 33. Three younger heterozygous sisters and a brother noticed exercise-induced myalgia and weakness since their teens. In sum, a homozygous p.W1327X mutation leads to a severe generalized glycogenosis types 3a and 3b within the same family. Even heterozygous p.W1327X mutation carriers may present with mild non-progressive neuromuscular symptoms, such as exercise-induced myalgia and fatigue.
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PMID:Clinicopathological analysis of the homozygous p.W1327X AGL mutation in glycogen storage disease type 3. 1892 25

Glycogen storage diseases (GSDs) comprise a large, heterogeneous group of disorders characterized by abnormal glycogen deposition. Multiple cases in the literature have demonstrated an association between GSD type I and pulmonary arterial hypertension (PAH). We now also report on two patients with GSD type III and PAH, a novel association. The first patient was a 16-year-old girl of Nicaraguan descent with a history of hepatomegaly and growth retardation. Molecular testing identified a homozygous 17delAG mutation in AGL consistent with GSD type IIIb. At the age of 16, she was found to have PAH and was started on medical therapy. Two years later, she developed acute chest pain and died shortly thereafter. The second patient is a 13-year-old girl of Colombian descent homozygous for the c.3911dupA mutation consistent with GSD IIIa. An echocardiogram at age 2 showed left ventricular hypertrophy, which resolved following the institution of a high protein, moderate carbohydrate diet during the day and continuous gastric-tube feeding overnight. At the age of 12, she was found to have pulmonary hypertension. She was started on sildenafil, and her clinical status has shown marked improvement including normalization of her elevated transaminases. PAH may be a rare association in patients with GSD IIIa and IIIb and should be evaluated with screening echocardiograms for cardiac hypertrophy or if they present with symptoms of right-sided heart failure such as shortness of breath, chest pain, cyanosis, fatigue, dizziness, syncope, or edema. Early diagnosis of PAH is important as increasingly effective treatments are now available.
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PMID:Two Cases of Pulmonary Hypertension Associated with Type III Glycogen Storage Disease. 2343 Aug 32

In glycogen storage disease type III (GSD III), deficiency of the debranching enzyme causes storage of an intermediate glycogen molecule (limit dextrin) in the affected tissues. In subtype IIIa hepatic tissue, skeletal- and cardiac muscle tissue is affected, while in subtype IIIb only hepatic tissue is affected. Cardiac storage of limit dextrin causes a form of cardiomyopathy, which resembles primary hypertrophic cardiomyopathy on cardiac ultrasound. We present a 32-year-old GSD IIIa patient with severe left ventricular hypertrophy (LVH) first diagnosed at the age of 8 years. LVH remained stable and symptomless until the patient presented at age 25 years with increasing dyspnea, fatigue, obesity, and NYHA (New York Heart Association) functional classification two out of four. Dyspnea, fatigue, and obesity progressed, and at age 28 years she was severely symptomatic with NYHA classification 3+ out of 4. On echocardiogram and electrocardiogram, the LVH had progressed as well. Initially, she was rejected for cardiac transplantation because of severe obesity. Therefore, a 900 cal, high protein diet providing 37% of total energy was prescribed during 4 months on which 10 kg weight loss was achieved. However, her symptoms as well as the electrocardiographic and echocardiographic LVH indices had improved dramatically - ultimately deferring cardiac transplantation. Thereafter, the caloric intake was increased to 1,370 cal per day, and the high protein intake was continued providing 43% of total energy. After 3 years of follow-up, the patient remains satisfied with reasonable exercise tolerance and minor symptoms in daily life.
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PMID:Heart Failure Due to Severe Hypertrophic Cardiomyopathy Reversed by Low Calorie, High Protein Dietary Adjustments in a Glycogen Storage Disease Type IIIa Patient. 2343 Sep 11

Myopathic symptoms in Glycogen Storage Disease Type IIIa (GSD IIIa) are generally ascribed to the muscle wasting that these patients suffer in adult life, but an inability to debranch glycogen likely also has an impact on muscle energy metabolism. We hypothesized that patients with GSD IIIa can experience exercise intolerance due to insufficient carbohydrate oxidation in skeletal muscle. Six patients aged 17-36-years were studied. We determined VO 2peak (peak oxygen consumption), the response to forearm exercise, and the metabolic and cardiovascular responses to cycle exercise at 70% of VO 2peak with either a saline or a glucose infusion. VO 2peak was below normal. Glucose improved the work capacity by lowering the heart rate, and increasing the peak work rate by 30% (108 W with glucose vs. 83 W with placebo, p=0.018). The block in muscle glycogenolytic capacity, combined with the liver involvement caused exercise intolerance with dynamic skeletal muscle symptoms (excessive fatigue and muscle pain), and hypoglycemia in 4 subjects. In this study we combined anaerobic and aerobic exercise to systematically study skeletal muscle metabolism and exercise tolerance in patients with GSD IIIa. Exercise capacity was significantly reduced, and our results indicate that this was due to a block in muscle glycogenolytic capacity. Our findings suggest that the general classification of GSD III as a glycogenosis characterized by fixed symptoms related to muscle wasting should be modified to include dynamic exercise-related symptoms of muscle fatigue. A proportion of the skeletal muscle symptoms in GSD IIIa, i.e. weakness and fatigue, may be related to insufficient energy production in muscle.
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PMID:Exercise intolerance in Glycogen Storage Disease Type III: weakness or energy deficiency? 2350 72

Glycogen storage disease type III (GSDIII) is an autosomal recessive disorder caused by mutations in the AGL gene coding for the glycogen debranching enzyme. Current therapy is based on dietary adaptations but new preclinical therapies are emerging. The identification of outcome measures which are sensitive to disease progression becomes critical to assess the efficacy of new treatments in upcoming clinical trials. In order to prepare future longitudinal studies or therapeutic trials with large cohorts, information about disease progression is required. In this study we present preliminary longitudinal data of Motor Function Measure (MFM), timed tests, Purdue pegboard test, and handgrip strength collected over 5 to 9years of follow-up in 13 patients with GSDIII aged between 13 and 56years old. Follow-up for nine of the 13 patients was up to 9years. Similarly to our previous cross-sectional retrospective study, handgrip strength significantly decreased with age in patients older than 37years. MFM scores started to decline after the age of 35. The Purdue pegboard score also significantly reduced with increasing age (from 13years of age) but with large inter-visit variations. The time to stand up from a chair or to climb 4 stairs increased dramatically in some but not all patients older than 30years old. In conclusion, this preliminary longitudinal study suggests that MFM and handgrip strength are the most sensitive muscle function outcome measures in GSDIII patients from the end of their third decade. Sensitive muscle outcome measures remain to be identified in younger GSDIII patients but is challenging as muscle symptoms remain discrete and often present as accumulated fatigue.
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PMID:Long term longitudinal study of muscle function in patients with glycogen storage disease type IIIa. 2888 51