ICD-10: E74.1

Disorders of fructose metabolism, classified under ICD-10 code E74.1, encompass a range of metabolic conditions that affect the body's ability to process fructose, a simple sugar found in many fruits and sweeteners. This condition primarily includes hereditary fructose intolerance (HFI), which is the most notable disorder in this category.

Clinical Description

Hereditary Fructose Intolerance (HFI)

HFI is a genetic disorder caused by a deficiency of the enzyme aldolase B, which is crucial for the metabolism of fructose. When individuals with HFI consume fructose, sucrose, or sorbitol, they experience a toxic accumulation of fructose-1-phosphate in the liver, leading to severe hypoglycemia and other metabolic disturbances.

Symptoms

The symptoms of HFI typically manifest after the introduction of fructose or sucrose into the diet, often during weaning when fruits and sweet foods are introduced. Common symptoms include:

• Hypoglycemia: Low blood sugar levels can lead to symptoms such as dizziness, sweating, irritability, and fainting.
• Abdominal Pain: Patients may experience severe abdominal discomfort, often accompanied by nausea and vomiting.
• Failure to Thrive: In infants and young children, the inability to metabolize fructose can lead to poor growth and development.
• Liver Damage: Chronic exposure to fructose can result in liver dysfunction, which may be indicated by elevated liver enzymes.

Diagnosis

Diagnosis of HFI typically involves a combination of clinical evaluation, dietary history, and biochemical tests. Key diagnostic methods include:

• Genetic Testing: Identification of mutations in the ALDOB gene, which encodes the aldolase B enzyme.
• Biochemical Tests: Measurement of fructose and fructose-1-phosphate levels in the blood and urine can help confirm the diagnosis.
• Dietary Challenge: In some cases, a controlled dietary challenge may be conducted under medical supervision to observe the metabolic response to fructose.

Management

The primary management strategy for individuals with HFI is strict dietary restriction of fructose, sucrose, and sorbitol. This involves:

• Dietary Education: Patients and families must be educated about reading food labels and avoiding foods that contain fructose or sucrose.
• Nutritional Support: Ensuring adequate nutrition through alternative sources of carbohydrates that do not contain fructose.

Other Disorders of Fructose Metabolism

While HFI is the most prominent disorder under E74.1, other less common conditions may also be classified here, including:

• Fructose Malabsorption: A condition where the intestines cannot absorb fructose properly, leading to gastrointestinal symptoms such as bloating, diarrhea, and abdominal pain.
• Fructose-1,6-bisphosphatase deficiency: A rare metabolic disorder that affects gluconeogenesis, leading to hypoglycemia and metabolic acidosis.

Conclusion

Disorders of fructose metabolism, particularly hereditary fructose intolerance, represent significant metabolic challenges that require careful management and dietary modifications. Early diagnosis and intervention are crucial to prevent serious complications associated with the accumulation of toxic metabolites. Individuals diagnosed with these disorders must work closely with healthcare providers to ensure a balanced diet while avoiding harmful sugars.

Disorders of fructose metabolism, classified under ICD-10 code E74.1, encompass a range of genetic conditions that affect the body's ability to metabolize fructose, a sugar found in many fruits and sweeteners. The most notable of these disorders include hereditary fructose intolerance (HFI) and fructose-1,6-bisphosphatase deficiency. Understanding the clinical presentation, signs, symptoms, and patient characteristics associated with these disorders is crucial for diagnosis and management.

Clinical Presentation

Hereditary Fructose Intolerance (HFI)

HFI is a genetic disorder caused by a deficiency of the enzyme aldolase B, which is essential for the metabolism of fructose. The clinical presentation typically occurs after the introduction of fructose or sucrose into the diet, often during weaning when fruits and sweet foods are introduced.

Signs and Symptoms

• Acute Symptoms: After ingestion of fructose, patients may experience severe abdominal pain, vomiting, and hypoglycemia. These symptoms can occur within hours of consuming fructose-containing foods.
• Chronic Symptoms: If fructose is consumed repeatedly, chronic symptoms may develop, including:
• Failure to thrive: In infants and young children, this can manifest as poor growth and weight gain.
• Liver dysfunction: Symptoms may include jaundice and hepatomegaly due to liver damage.
• Renal issues: Prolonged exposure to fructose can lead to renal tubular dysfunction.
• Behavioral Changes: Some patients may exhibit irritability or lethargy due to hypoglycemia.

Fructose-1,6-Bisphosphatase Deficiency

This is a rarer disorder characterized by a deficiency in the enzyme fructose-1,6-bisphosphatase, which plays a critical role in gluconeogenesis.

Signs and Symptoms

• Hypoglycemia: Similar to HFI, patients may experience episodes of hypoglycemia, particularly during fasting or illness.
• Metabolic Acidosis: Patients may present with metabolic acidosis due to the accumulation of lactate and other metabolites.
• Failure to Thrive: Infants may show poor growth and developmental delays.
• Liver Enlargement: Hepatomegaly can also be a feature, although it may be less pronounced than in HFI.

Patient Characteristics

Demographics

• Age of Onset: Symptoms of HFI typically present in infancy or early childhood, often after dietary changes. Fructose-1,6-bisphosphatase deficiency may also present in infancy but can sometimes be diagnosed later in childhood.
• Genetic Background: Both disorders are inherited in an autosomal recessive manner, meaning that both parents must carry the gene mutation for a child to be affected. HFI is more common in certain populations, such as those of Northern European descent.

Family History

• A positive family history of metabolic disorders may be present, as these conditions are genetic. Parents may report similar symptoms in siblings or other family members.

Dietary Habits

• Patients often have a history of consuming foods high in fructose or sucrose, which can trigger symptoms. Dietary restrictions are crucial for managing these conditions.

Conclusion

Disorders of fructose metabolism, particularly hereditary fructose intolerance and fructose-1,6-bisphosphatase deficiency, present with a range of symptoms primarily related to gastrointestinal distress, metabolic disturbances, and growth issues. Early recognition and dietary management are essential to prevent serious complications associated with these conditions. If you suspect a patient may have a disorder of fructose metabolism, a thorough clinical evaluation, including dietary history and genetic testing, is recommended to confirm the diagnosis and guide treatment.

Disorders of fructose metabolism, classified under ICD-10 code E74.1, encompass a range of conditions primarily related to the body's inability to properly metabolize fructose, a sugar found in many fruits and sweeteners. Below are alternative names and related terms associated with this condition.

Alternative Names

1. Hereditary Fructose Intolerance (HFI): This is the most common condition associated with E74.1, where individuals lack the enzyme aldolase B, leading to severe reactions to fructose ingestion.

2. Fructose Malabsorption: This term refers to the inability to absorb fructose in the intestines, which can lead to gastrointestinal symptoms but is distinct from hereditary fructose intolerance.

3. Fructose-1,6-bisphosphate Aldolase Deficiency: A rare genetic disorder that affects the metabolism of fructose and can lead to various metabolic issues.

4. Fructose-1-Phosphate Aldolase Deficiency: Another rare condition that can affect fructose metabolism, though it is less commonly referenced.

Related Terms

1. Carbohydrate Metabolism Disorders: A broader category that includes various disorders affecting the metabolism of carbohydrates, including fructose.

2. Metabolic Disorders: This term encompasses a wide range of conditions that disrupt normal metabolism, including those affecting fructose.

3. Enzyme Deficiencies: Refers to the lack of specific enzymes necessary for the metabolism of fructose, such as aldolase B in hereditary fructose intolerance.

4. Dietary Fructose Intolerance: A term that may be used to describe symptoms related to the ingestion of fructose, though it is not a formal diagnosis like HFI.

5. Fructose Toxicity: This term may be used to describe the adverse effects that occur when individuals with fructose metabolism disorders consume fructose.

Conclusion

Understanding the various names and related terms for disorders of fructose metabolism is crucial for accurate diagnosis and treatment. Hereditary fructose intolerance is the most recognized condition under ICD-10 code E74.1, but other related terms highlight the complexity of fructose metabolism disorders. If you have further questions or need more specific information, feel free to ask!

The diagnosis of disorders of fructose metabolism, specifically coded as ICD-10 code E74.1, involves a combination of clinical evaluation, biochemical testing, and genetic analysis. Here’s a detailed overview of the criteria used for diagnosing this condition.

Overview of Disorders of Fructose Metabolism

Disorders of fructose metabolism primarily include hereditary fructose intolerance (HFI), which is a genetic condition that affects the body's ability to metabolize fructose, a sugar found in many fruits and sweeteners. The inability to properly process fructose can lead to serious health issues, particularly after the consumption of fructose-containing foods.

Diagnostic Criteria

1. Clinical History

• Symptoms: Patients often present with symptoms such as abdominal pain, vomiting, hypoglycemia, and failure to thrive in infants after the introduction of fructose or sucrose into their diet. A detailed dietary history is crucial to identify any correlation between symptoms and fructose intake.
• Family History: A family history of similar symptoms or confirmed cases of fructose metabolism disorders can support the diagnosis, as these conditions are typically inherited in an autosomal recessive manner.

2. Biochemical Testing

• Fructose Tolerance Test: This test involves administering a fructose load and measuring blood glucose levels. In individuals with HFI, there is typically a significant drop in blood glucose levels due to the inability to metabolize fructose properly.
• Urine Analysis: The presence of fructose in the urine can be indicative of a fructose metabolism disorder. In HFI, urine tests may show elevated levels of fructose and other metabolites.
• Blood Tests: Testing for elevated levels of fructose and other related metabolites in the blood can help confirm the diagnosis.

3. Genetic Testing

• Molecular Genetic Testing: Identification of mutations in the ALDOB gene, which encodes the enzyme aldolase B, is definitive for diagnosing hereditary fructose intolerance. Genetic testing can confirm the presence of pathogenic variants associated with the disorder.

4. Exclusion of Other Conditions

• Differential Diagnosis: It is essential to rule out other metabolic disorders that may present with similar symptoms, such as galactosemia or other carbohydrate metabolism disorders. This may involve additional metabolic testing and consultations with specialists in metabolic diseases.

Conclusion

The diagnosis of disorders of fructose metabolism, particularly hereditary fructose intolerance, relies on a comprehensive approach that includes clinical evaluation, biochemical testing, and genetic analysis. Early diagnosis is crucial to prevent severe complications associated with the ingestion of fructose, and management typically involves dietary restrictions to avoid fructose and sucrose. If you suspect a fructose metabolism disorder, consulting a healthcare provider for appropriate testing and diagnosis is essential.

Disorders of fructose metabolism, specifically classified under ICD-10 code E74.1, encompass a range of metabolic conditions that affect the body's ability to process fructose, a simple sugar found in many fruits and sweeteners. The most notable disorders in this category include hereditary fructose intolerance (HFI) and fructose malabsorption. Understanding the standard treatment approaches for these conditions is crucial for managing symptoms and preventing complications.

Overview of Disorders of Fructose Metabolism

Hereditary Fructose Intolerance (HFI)

HFI is a genetic disorder caused by a deficiency of the enzyme aldolase B, which is essential for the metabolism of fructose. Individuals with HFI cannot properly break down fructose, leading to toxic accumulation in the liver, kidneys, and small intestine. Symptoms often manifest after the introduction of fructose into the diet, typically through fruits, sweeteners, or certain vegetables.

Fructose Malabsorption

Fructose malabsorption, on the other hand, is characterized by the inability to absorb fructose efficiently in the intestines, leading to gastrointestinal symptoms such as bloating, diarrhea, and abdominal pain. This condition is not inherited but can be influenced by other gastrointestinal disorders.

Standard Treatment Approaches

Dietary Management

The cornerstone of treatment for both HFI and fructose malabsorption is dietary modification:

1. Elimination of Fructose:
   - For individuals with HFI, strict avoidance of fructose and sucrose (which breaks down into fructose and glucose) is essential. This includes avoiding foods such as:

   • Fruits (especially high-fructose varieties like apples, pears, and cherries)
   • Sweeteners (like honey, high-fructose corn syrup, and table sugar)
   • Certain vegetables (like asparagus and sugar snap peas) that contain fructose.
   • Patients are often advised to read food labels carefully to avoid hidden sources of fructose and sucrose[1].

2. Low Fructose Diet:
   - In cases of fructose malabsorption, a low-fructose diet may be recommended. This involves limiting foods high in fructose while allowing for some tolerance, as individuals may still be able to consume small amounts without significant symptoms[2].

Nutritional Counseling

• Professional Guidance: Consulting with a registered dietitian or nutritionist is beneficial for individuals with these disorders. They can provide personalized meal plans, educate patients about safe food choices, and ensure nutritional adequacy despite dietary restrictions[3].

Monitoring and Support

• Regular Follow-ups: Continuous monitoring of symptoms and dietary adherence is important. Patients may need periodic assessments to adjust their diets based on tolerance levels and nutritional needs[4].
• Support Groups: Joining support groups can provide emotional support and practical advice from others facing similar dietary challenges.

Medical Management

• Symptomatic Treatment: For individuals with fructose malabsorption, over-the-counter medications such as antacids or anti-diarrheal agents may be used to manage gastrointestinal symptoms. However, these should be used under the guidance of a healthcare provider[5].

Genetic Counseling

• Family Planning: For families affected by HFI, genetic counseling may be recommended to understand the inheritance patterns and implications for future children. This can help in making informed decisions regarding family planning[6].

Conclusion

In summary, the management of disorders of fructose metabolism, particularly hereditary fructose intolerance and fructose malabsorption, primarily revolves around dietary modifications to eliminate or reduce fructose intake. Nutritional counseling and ongoing support are vital for ensuring that individuals maintain a balanced diet while avoiding trigger foods. Regular follow-ups with healthcare providers can help manage symptoms effectively and improve the quality of life for those affected by these metabolic disorders.