Tarui Disease (GSD VII)MANAGEMENT

ENDOCRINE AND METABOLIC PRESENTATIONS · 12 SECTIONS

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660 items

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Cardiovascular Presentations71▾

Respiratory Presentations52▾

Neurological Presentations83▾

Gastrointestinal Presentations74▾

Genitourinary and Reproductive Presentations48▾

Infectious Disease Presentations148▾

Trauma Presentations89▾

Toxicologic Presentations80▾

Psychiatric Presentations26▾

Musculoskeletal and Rheumatologic Presentations96▾

Dermatology Presentations23▾

Environmental and Exposure Presentations27▾

Hematologic and Oncologic Presentations36▾

Pediatric-Specific Presentations19▾

Endocrine and Metabolic Presentations45▾

Acute Porphyria Adrenal crisis Adrenal Insufficiency (Addisonian Crisis)Dehydration Diabetes Insipidus Diabetic Ketoacidosis (DKA)Euglycemic DKA (SGLT2 inhibitor)Galactosemia GLP-1 receptor agonist complications (retained gastric contents, aspiration risk)Homocystinuria Hypercalcemia Hyperkalemia Hypermagnesemia Hypernatremia Hyperosmolar Hyperglycemic State (HHS)Hypertensive emergency Hypertensive urgency Hypocalcemia Hypoglycemia Hypogonadism (Acute Presentation)Hypokalemia Hypomagnesemia Hyponatremia Hypoparathyroidism (Tetany)Insulin pump failure Maple Syrup Urine Disease (Crisis)Medium-Chain Acyl-CoA Dehydrogenase Deficiency (MCAD)Metabolic Acidosis Metabolic Alkalosis Myasthenia gravis crisis Myxedema coma Pellagra Pheochromocytoma (Crisis)Pituitary Apoplexy Pompe Disease (GSD II)Respiratory Acidosis Respiratory Alkalosis Scurvy SIADH Starvation Ketosis Tarui Disease (GSD VII)Thyroid storm Tyrosinemia Vitamin D Deficiency (Severe-Rickets)Von Gierke Disease (GSD I)

ENT and Maxillofacial Presentations27▾

Ophthalmologic Presentations19▾

Obstetric Presentations23▾

Systemic and Miscellaneous Presentations17▾

01Approach to the Critical Patient/attcp48

Immediate priorities

›Acute rhabdomyolysis crisis recognition

›Markedly elevated creatine kinase (CK > 10x upper limit of normal)

›Risk of acute kidney injury from myoglobin precipitation

›Hyperkalemia from muscle cell lysis

›Hypocalcemia and hyperphosphatemia secondary to muscle destruction

›Myoglobinuria

›Cola-colored or dark urine on presentation

›Dipstick-positive for blood with no red blood cells on microscopy

›Severe electrolyte derangement

›Hyperkalemia > 6.0 mmol/l

›Cardiac arrhythmia risk with hyperkalemia

›Respiratory threat in severe infantile form

›Hypotonia with respiratory failure requiring ventilatory support

›Presents in neonatal or early infantile period

›Associated cardiomyopathy may compound respiratory compromise

›Intubation and mechanical ventilation if respiratory failure established

›Class I recommendation for airway protection in infantile GSD VII

›Hemolytic crisis recognition

›Jaundice with rapidly falling hemoglobin

›Indirect bilirubin elevation

›Reticulocytosis indicates compensated hemolysis

›If hemoglobin < 70 g/l with hemodynamic instability, transfusion threshold consideration

Monitoring and targets

›Rhabdomyolysis monitoring bundle

›Serial CK every 6-12 hours until trending downward

›CK peak usually within 24-72 hours of event

›Target: CK declining and < 1000 U/l before discharge

02History/hx57

Presenting symptoms

›Exercise intolerance

›Onset typically in childhood or second to third decade of life

›Myalgia, cramping, and stiffness with high-intensity or isometric exercise

›Symptoms provoked by short-duration exertion rather than prolonged activity

›Out-of-wind phenomenon

›Worsening exercise intolerance after carbohydrate-rich meals

›Distinguishes GSD VII from McArdle disease (GSD V)

›Absence of second wind phenomenon

›Unlike McArdle disease, no symptom relief after brief rest and resumed activity

›Myoglobinuria episodes

›Dark or cola-colored urine after exertion

›Indicates significant rhabdomyolysis

›Risk factor for acute kidney injury

›Nausea and vomiting commonly accompany exercise-induced crises

Key historical features

›Meal and exercise relationship

›Better exercise tolerance in the fasting state

›Increased circulating free fatty acids improve muscle fuel availability

›Paradoxical improvement with fasting distinguishes from most other conditions

›High-fat meal before exercise may improve performance

›Provides free fatty acids as alternative fuel to blocked glycolytic pathway

›Symptom triggers

›Short-duration high-intensity exercise is primary trigger

›Isometric exercise particularly provocative

›Activities relying on anaerobic glycolysis most symptomatic

›Post-prandial exercise significantly worsened after carbohydrate meal

›Hemolytic symptoms

03Physical Exam/exam39

General and vital signs

›Appearance

›Generally normal between episodes in classical form

›Muscle tenderness and swelling during or after acute crises

›No muscle hypertrophy (contrast with some McArdle disease patients)

›Jaundice or scleral icterus

›From compensated hemolysis due to partial red cell PFK deficiency

›Vital signs

›Tachycardia

›During acute rhabdomyolysis or hemolytic crisis

›Blood pressure

›Hypotension if severe dehydration or hemolysis

Musculoskeletal examination

›Muscle strength assessment

›Classical form: normal strength between episodes

›Proximal weakness developing in late-onset form after age 50

›Fixed weakness in late-onset form is progressive

›Infantile form: profound hypotonia from birth

›Associated joint contractures and respiratory muscle weakness

›Muscle tenderness

›Diffuse or focal tenderness during acute episodes

›Limb swelling if compartment syndrome developing

›Compartment pressure assessment if tense swelling present

Neurological examination

›Cranial nerves

›Typically normal in classical form

›Infantile form may have dysphagia

›Peripheral motor examination

04Differential Diagnosis/ddx42

Glycogen storage diseases

›McArdle disease (GSD V) — most important mimic

›ICD-10: E74.04

›Phosphorylase deficiency rather than PFK deficiency

›Key distinguishing feature: second wind phenomenon present in McArdle disease

›Pre-exercise glucose IMPROVES McArdle disease (opposite to GSD VII)

›No hemolytic anemia in McArdle disease

›Forearm ischemic exercise test: no lactate rise in both; ammonia rises normally in McArdle, blunted in GSD VII

›Other glycolytic defects

›Phosphoglycerate kinase deficiency (GSD IX)

›Only other glycogenosis with combined myopathy and hemolytic anemia

›X-linked inheritance distinguishes from autosomal recessive GSD VII

›Phosphoglycerate mutase deficiency (GSD X)

›Myopathy without hemolytic anemia

›Biochemical enzyme assay required for distinction

›Lactate dehydrogenase-A deficiency (GSD XI)

›Exercise intolerance with skin rash

›Enzyme-specific assay diagnostic

Fatty acid oxidation disorders

›Carnitine palmitoyltransferase II (CPT II) deficiency

›ICD-10: E71.314

›Symptoms during prolonged exercise and fasting rather than short intense activity

›No hemolytic anemia

›Urine acylcarnitine profile abnormal

›Plasma acylcarnitine distinguishes from GSD VII

›Very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency

›Prolonged exercise and fasting triggers

›Abnormal acylcarnitine profile on newborn screening or testing

05Laboratory Tests/lt62

Creatine kinase and muscle markers

›Creatine kinase (CK)

›Baseline elevation in most GSD VII patients

›Typically 500-3000 U/l at rest

›Markedly elevated during rhabdomyolysis, > 10,000 U/l

›Serial CK monitoring during acute episodes

›Peak within 24-72 hours

›Declining CK indicates resolving rhabdomyolysis

›CK-MM isoform predominates in rhabdomyolysis

Hemolysis markers

›Reticulocyte count

›Elevated reticulocyte count indicates compensated hemolysis

›Typical range 2-5% (upper normal)

›Compensated state explains why anemia may be absent

›Elevated in nearly all classical GSD VII patients

›Indirect bilirubin

›Elevated from hemoglobin catabolism

›Differentiates from direct bilirubin elevation (hepatic disease)

›Combination of elevated indirect bilirubin and reticulocytosis is hallmark

›Lactate dehydrogenase (LDH)

›Elevated from hemolysis and muscle cell lysis

›Cannot distinguish source without CK and bilirubin correlation

Metabolic and renal panel

›Uric acid

›Elevated (hyperuricemia) from myogenic purine degradation

›Myogenic hyperuricemia distinguishes from dietary gout

›Allopurinol indicated if symptomatic gout or significantly elevated levels

›Risk of acute urate nephropathy during rhabdomyolysis

06Diagnostic Tests/dt65

Scoring Systems

›Clinical classification of GSD VII subtypes

›Classical subtype

›Onset childhood to young adulthood

›Exercise intolerance with myoglobinuria episodes

›Compensated hemolytic anemia

›Most common subtype; compatible with normal lifespan

›Severe infantile subtype

›Hypotonia at birth

›Cardiomyopathy and respiratory failure

›Fatal within first year of life in most reported cases

›Late-onset subtype

›Progressive fixed proximal weakness after age 50

›Minimal or absent hemolytic anemia

›Hemolytic subtype

›Hemolysis without myopathy

›Rare; incomplete muscle PFK deficiency

›Rhabdomyolysis severity scoring

›Mild: CK < 5x ULN without myoglobinuria

›Outpatient monitoring may be appropriate

›Moderate: CK 5-50x ULN with myoglobinuria

›Hospital admission for IV fluids and monitoring

›Severe: CK > 50x ULN with AKI or hyperkalemia

›ICU-level monitoring required

MRI

›Muscle MRI in GSD VII

›Utility in late-onset form with fixed weakness

›T1-weighted imaging: fatty replacement of affected muscles

07Disposition/dispo45

Admission criteria

›Indications for hospital admission

›Significant rhabdomyolysis

›CK > 5x upper limit of normal with myoglobinuria

›Rising creatinine or oliguria suggesting AKI

›Electrolyte derangements

›Hyperkalemia > 5.5 mmol/l or with ECG changes

›Hypocalcemia with symptoms

›Hemolytic crisis

›Falling hemoglobin with symptomatic anemia

›Hemodynamic instability

›Infantile form with respiratory distress or cardiomyopathy

›PICU admission for mechanical ventilatory support

›ICU admission indications

›Severe AKI requiring renal replacement therapy consideration

›Hyperkalemia unresponsive to medical management

›Respiratory failure in infantile form

›Mechanical ventilation requirement

›Hemodynamic instability from severe hemolysis

Discharge criteria

›Safe discharge parameters

›CK trending downward and < 1000 U/l or at patient baseline

›No myoglobinuria on repeat urinalysis

›Creatinine at or near baseline

›Electrolytes within normal range

›Potassium < 5.0 mmol/l

›Adequate oral hydration achievable

›Tolerating oral fluids

08Treatment/t76

Acute rhabdomyolysis management

›IV fluid resuscitation

›Normal saline (0.9% NaCl) preferred initial fluid

›Initial bolus 1-2 L over 30-60 minutes

›Target urine output > 200 mL/hour during myoglobinuric phase

›Maintenance rate 200-400 mL/hour until myoglobinuria clears

›Titrate to urine output and fluid balance

›Avoid glucose-containing IV fluids

›Glucose worsens glycolytic block symptoms and increases metabolic demand

›Urinary alkalinization

›Sodium bicarbonate 1-1.5 mEq/kg IV

›Target urine pH > 6.5 to reduce myoglobin cast formation

›Reduces tubular precipitation of myoglobin in acidic environment

›Monitor urine pH every 2-4 hours

›Avoid over-alkalinization; serum pH target < 7.50

›Evidence base: expert consensus; no high-level RCT data

Electrolyte management

›Hyperkalemia treatment

›Mild hyperkalemia (5.5-6.0 mmol/l without ECG changes)

›Calcium resonium (sodium polystyrene sulfonate) 15-30 g orally

›Low-potassium diet and IV fluid dilution

›Moderate-severe hyperkalemia (> 6.0 mmol/l or ECG changes)

›Calcium gluconate 1-2 g IV over 5-10 minutes for cardiac membrane stabilization

›Regular insulin 10 units IV with 50 mL of 50% dextrose (glucose) only if hypoglycemic risk outweighs benefit

›Salbutamol (albuterol) 10-20 mg nebulized to shift potassium intracellularly

›Renal replacement therapy if refractory

›Repeat potassium every 2-4 hours until stable

›Hypocalcemia management

›Calcium gluconate 10 mL of 10% solution IV over 10 minutes

›For symptomatic hypocalcemia or severe depletion

›Cardiac monitoring during IV calcium administration

›Oral calcium carbonate for mild asymptomatic hypocalcemia

Long-term dietary management

›Avoidance of pre-exercise carbohydrates

›Single most important dietary intervention in GSD VII

›Glucose inhibits lipolysis, depriving muscle of fatty acid fuel

›Worsens exercise tolerance via out-of-wind mechanism

›Haller and Lewis (NEJM, 1991) demonstrated glucose infusion markedly impairs maximal work intensity and oxygen uptake compared to fasting conditions

›Ketogenic or modified Atkins diet

›Provides alternative fuel (free fatty acids and ketones) bypassing glycolytic block

›5-year case study showed improved exercise tolerance and normalized ammonia levels

›Improved oxygen uptake and ventilatory parameters on ketogenic diet

›Implementation under medical and nutritional supervision mandatory

›Modified Atkins diet (less restrictive) preferred for long-term adherence

›Ketones provide alternative fuel at the level of entry into Krebs cycle

›Timing: high-fat, low-carbohydrate meal 2-3 hours before planned exercise

›Fasting state before exercise may paradoxically improve performance

›Hydration

›Adequate fluid intake before, during, and after exercise

›Reduces risk of myoglobinuria and rhabdomyolysis

›Minimum 2-3 L daily oral fluid intake

Activity modification

›Exercise prescription

›Avoid high-intensity and isometric exercise

›Triggers anaerobic glycolysis reliant on blocked PFK pathway

›Gradual progressive aerobic exercise recommended

›Aerobic low-intensity exercise uses fatty acid oxidation

›Start at 40-50% maximal heart rate and slowly progress

›Warm-up protocol

›Slow warm-up to allow fatty acid oxidation to engage before intensity increases

›Pause at symptom onset and allow brief rest to allow metabolic switch

›Stop immediately if myalgia escalates or dark urine noted

Pharmacologic interventions

›Hyperuricemia management

›Allopurinol 300 mg orally once daily

›For symptomatic gout or significantly elevated uric acid

›Reduces xanthine oxidase-mediated urate production

›Ensure adequate hydration with allopurinol to prevent xanthine nephropathy

›Avoidance of myotoxic medications

›Cyclosporine

›Documented to worsen GSD VII myopathy severely

›Avoid in transplant patients if alternative immunosuppression possible

›Amiodarone

›Reported to cause late and severe myopathy in GSD VII

›Use alternative antiarrhythmics when possible

›Statins

›Use with extreme caution; myotoxic risk compounded by existing myopathy

›No established pharmacotherapy for underlying PFK deficiency

›Enzyme replacement therapy not available for GSD VII

›Gene therapy under research; no approved treatment as of 2024

›Creatine monohydrate: established benefit in McArdle disease; not validated for GSD VII

09Special Populations/sp74

Pregnancy

›Physiological considerations

›Increased metabolic demands of pregnancy

›Growing fetus increases glycolytic demand on maternal tissues

›Weight gain increases exercise intensity for equivalent activity

›Hyperemesis and dietary restrictions may limit fat intake

›Reduced fatty acid availability during severe nausea

›Maternal risks

›Increased risk of rhabdomyolysis during labor and delivery

›Uterine muscle is PFK-deficient in GSD VII

›Prolonged or difficult labor may precipitate rhabdomyolysis

›Myoglobinuria in pregnancy carries AKI risk

›Aggressive hydration and monitoring required during labor

›Renal function monitoring throughout pregnancy

›Creatinine at each trimester

›Dietary management in pregnancy

›Ketogenic diet NOT recommended in pregnancy

›Potential teratogenicity and nutritional concerns

›High-fat balanced diet may be substituted

›Nutritional counseling with maternal-fetal medicine input

›Avoid prolonged pre-exercise carbohydrate loading

›Fetal considerations

›Autosomal recessive inheritance: 25% risk of affected fetus if both parents carry PFKM mutation

›Prenatal genetic testing available

›Carrier testing of partner if index case diagnosed

›Peripartum management plan with obstetrics and metabolism team

Geriatric

›Late-onset subtype predominates

›Progressive fixed proximal weakness after age 50

›Distinguishable from classical form by progressive nature

›Falls risk with proximal lower limb weakness

›Reduced compensatory capacity for rhabdomyolysis

›Age-related decline in renal reserve increases AKI risk

›Comorbidity considerations

›Polypharmacy risk with myotoxic medications

›Statin use common in elderly; requires careful benefit-risk assessment

›Cyclosporine and amiodarone use in cardiac or transplant patients

›Reduced cardiac reserve if hypertrophic cardiomyopathy present

›Geriatric patients may have established cardiovascular disease

›Dietary challenges

›Ketogenic diet implementation more challenging in elderly

›Renal function may limit protein intake adjustments

›Bone health concerns with prolonged ketogenic diet

›Adequate protein intake to prevent sarcopenia alongside low-carbohydrate diet

›Activity and rehabilitation

›Physical therapy consultation for fall prevention

›Resistance training at low intensity to maintain muscle mass

›Supervised aerobic exercise program

Pediatrics

›Classical form in children

›Exercise intolerance onset typically in school-age years

›May present as reluctance to participate in physical education

›Myalgia and cramping with playground activities or sports

›Hemolytic anemia may be more apparent before exercise limitation recognized

›Jaundice and pallor may be presenting features in infants and toddlers

›Severe infantile form

›Hypotonia from birth with cardiomyopathy and respiratory failure

›Typically fatal within first year of life

›Mechanical ventilation and cardiac support measures

›Neonatal screening does not routinely include GSD VII

›Diagnosis often delayed until symptomatic presentation

›Diagnostic considerations in children

›Non-ischemic forearm exercise test adaptable for children > 5 years

›Requires cooperation for reliable lactate and ammonia response

›Genetic testing preferred for definitive diagnosis avoiding muscle biopsy in young children

›PFKM gene panel on blood sample

›Dietary management in children

›Low-carbohydrate, high-fat diet requires careful nutritional planning

›Growth monitoring mandatory with dietary restrictions

›Adequate calcium, vitamin D, and micronutrient supplementation

›School accommodation plans for exercise limitation

›Modified physical education participation

›Medical alert documentation for school staff

›Genetic counseling for families

›Sibling screening recommended when index case identified

›Genetic testing of parents to confirm carrier status

›25% recurrence risk with each pregnancy

10Background/b73

Epidemiology

›Prevalence and incidence

›Incidence estimated at < 1 per 1,000,000 live births

›Exact prevalence unknown due to underdiagnosis

›Rare disease classification in all jurisdictions

›Population clustering

›Higher prevalence in Ashkenazi Jewish population due to founder effect

›Higher prevalence in Japanese population due to distinct founder mutations

›Age and sex distribution

›Classical form: symptoms emerge in childhood, often school age

›Diagnosis often delayed by 10-15 years from symptom onset

›Both sexes equally affected (autosomal recessive)

›Late-onset form: progressive weakness after age 50

›Disease subtype distribution

›Classical form is the most common subtype

›Severe infantile and hemolytic subtypes are rare

›Late-onset form increasingly recognized in older patients

›ICD-10 coding

›ICD-10: E74.09 — Other glycogen storage disorders

›Also classified under E74.0 — Glycogen storage disease

Pathophysiology

›Enzymatic defect

›PFKM gene mutation on chromosome 1q32

›Encodes muscle isoform of phosphofructokinase (PFK-M)

›Autosomal recessive inheritance; biallelic mutations required for disease

›PFK catalyzes rate-limiting step of glycolysis

›Converts fructose-6-phosphate to fructose-1,6-bisphosphate

›Complete block in muscle glycolysis

›Tissue-specific isoforms explain dual phenotype

›Muscle: PFK is homotetrameric (M4); complete PFK absence causes myopathy

›No alternative isoforms in skeletal muscle to compensate

›Red blood cells: PFK is heterotetramer (M2L2 and L4); 50% residual activity

›Partial PFK deficiency in red cells causes compensated hemolytic anemia

›Explains why hemolysis is compensated and anemia often absent

›Out-of-wind phenomenon mechanism

›Glucose ingestion raises plasma glucose and insulin

›Insulin suppresses lipolysis, reducing circulating free fatty acids

›Muscle denied alternative fuel substrate

›PFK block prevents glycolysis; no fatty acids available

›Severe energy deficit during exercise after carbohydrate meal

›Fasting state promotes lipolysis

›Free fatty acids and ketones bypass glycolytic block

›Exercise tolerance paradoxically improved when fasting

›Myogenic hyperuricemia

›Failure of glycolysis leads to AMP accumulation

›AMP degraded to inosine and then to uric acid

›Purine nucleotide catabolism accelerated during exercise

›Hyperuricemia and gout result from chronic purine overproduction

›Glycogen and polyglucosan accumulation

›Blocked glycogen utilization leads to glycogen accumulation in muscle

›Subsarcolemmal polysaccharide deposits on biopsy

›Polyglucosan bodies may form from abnormal glycogen structure

Therapeutic Considerations

›Dietary bypass of glycolytic block

›Ketogenic diet and modified Atkins diet

›Ketone bodies enter Krebs cycle without requiring glycolysis

›Free fatty acids oxidized via beta-oxidation, bypassing PFK step

›Similä et al. (Frontiers in Neurology, 2020): 5-year ketogenic diet case study showed improved exercise tolerance, normalized ammonia, improved VO2

›Evidence base: case reports and case series; no RCTs available for rare disease

›Avoidance principle

›Carbohydrate restriction before exercise is cornerstone of management

›Haller and Lewis (NEJM, 1991): landmark study demonstrating glucose infusion worsens exercise capacity in GSD VII

›Level C evidence for dietary modification as primary intervention

›Medication avoidance

›Cyclosporine and amiodarone reported to cause severe myopathy worsening

›Mechanism: additional mitochondrial and metabolic toxicity compounding energy deficit

›Future therapeutic directions

›Gene therapy

›AAV-mediated PFKM gene delivery in animal models

›No approved human gene therapy for GSD VII as of 2024

›Substrate reduction therapy

›Theoretical potential for reducing glycogen accumulation

›Enzyme replacement therapy

›Not feasible for intracellular enzyme delivered to muscle

›Genetic counseling as therapeutic tool

›Prenatal diagnosis and family cascade testing prevent delayed diagnosis

11Patient Discharge Instructions/pdi43

copy discharge instructions

›Diagnosis and explanation

›You have been diagnosed with Tarui disease (glycogen storage disease type VII)

›This is a rare inherited condition where your muscles cannot use glucose for energy properly

›Your muscles must rely on fats and ketones for fuel instead of sugar

›This condition affects both your muscles and your red blood cells

›You may notice jaundice (yellow skin or eyes) and dark urine after exercise

›Diet instructions

›Do NOT eat carbohydrate-rich or sugary foods before exercise

›Eating carbohydrates before exercise worsens your muscle symptoms

›Bread, pasta, rice, sweets, and sports drinks before exercise should be avoided

›A high-fat, low-carbohydrate diet may improve your exercise tolerance

›Discuss a ketogenic or modified Atkins diet with your metabolic team

›Stay well-hydrated at all times

›Drink at least 2-3 litres of water daily

›Increase fluid intake before, during, and after exercise

›Activity instructions

›Avoid intense or isometric (straining) exercise

›Heavy weightlifting, sprinting, and sustained isometric holds are most likely to trigger symptoms

›Warm up slowly before any physical activity

›Allow your body to switch to fat-burning mode before increasing intensity

›Stop activity immediately if you notice severe muscle pain, cramping, or dark urine

›Medications and medical alert

›Carry a medical alert card or bracelet identifying your diagnosis

›List Tarui disease (GSD VII, PFK deficiency) on your medical alert

›Inform all healthcare providers of your diagnosis before any procedure or new medication

›Certain medications (cyclosporine, amiodarone, statins) can worsen your condition

›Do NOT take glucose or carbohydrate supplements before exercise as these worsen symptoms

12References/r36

Guidelines and key sources

›Beecher G, Fleming MD, Liewluck T. Hereditary myopathies associated with hematological abnormalities. Muscle and Nerve. 2022

›Comprehensive review of GSD VII with hemolytic anemia phenotype

›PMID: onlinelibrary.wiley.com/doi/10.1002/mus.27474

›DiMauro S, Lamperti C. Muscle glycogenoses. Muscle and Nerve. 2001

›Foundational classification and clinical description of GSD subtypes

›PMID: onlinelibrary.wiley.com/doi/10.1002/mus.1103

›Haller RG, Lewis SF. Glucose-Induced Exertional Fatigue in Muscle Phosphofructokinase Deficiency. New England Journal of Medicine. 1991

›Landmark clinical trial demonstrating out-of-wind mechanism

›NEJM 1991;324:364-369

›Similä ME, Auranen M, Piirilä PL. Beneficial Effects of Ketogenic Diet on Phosphofructokinase Deficiency (GSD VII). Frontiers in Neurology. 2020

›5-year case study supporting ketogenic diet as long-term intervention

›PMID: 32117019

›Filosto M et al. Late and Severe Myopathy in a Patient With Glycogenosis VII Worsened by Cyclosporine and Amiodarone. Frontiers in Neurology. 2018

›Case report establishing myotoxic drug interactions in GSD VII

›PMID: 30792690

›Musumeci O, Bruno C, Mongini T et al. Clinical Features and New Molecular Findings in Muscle Phosphofructokinase Deficiency (GSD Type VII). Neuromuscular Disorders. 2012

›Largest case series of GSD VII with molecular and clinical correlation

›PMID: 22133655

›Piirilä P, Similä ME, Palmio J et al. Unique Exercise Lactate Profile in Muscle Phosphofructokinase Deficiency (Tarui Disease). Frontiers in Neurology. 2016

›Forearm exercise test profile distinguishing GSD VII from McArdle disease

›PMID: 27303362

›Hannah WB, Derks TGJ, Drumm ML et al. Glycogen Storage Diseases. Nature Reviews Disease Primers. 2023

›Current comprehensive review of all glycogen storage diseases

›PMID: 37679331

›Tarnopolsky MA. Myopathies Related to Glycogen Metabolism Disorders. Neurotherapeutics. 2018

›Evidence-based management review including dietary therapies

›PMID: 30397902

Learn More: Tarui Disease (GSD VII)→

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Reviewed by SymptomDx Medical Team · Last reviewed August 18, 2026

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