hyperlipoproteinemia type V

Hyperlipoproteinemia Type V: A Rare Metabolic Disorder

Hyperlipoproteinemia type V, also known as Fredrickson type V, is a rare and severe form of hyperlipidemia characterized by the elevation of both plasma chylomicrons and triglycerides contained in very-low-density lipoproteins (VLDL) [5][15]. This condition is often associated with diabetes mellitus and is not caused by reduced lipoprotein lipase activity, unlike type I hyperlipoproteinemia [9].

Clinical Features

The clinical features of type V hyperlipoproteinemia may include:

• Eruptive xanthomata (skin lesions)
• Hepatosplenomegaly (enlargement of the liver and spleen)
• Lipemia retinalis (a condition where the retina appears cloudy due to high levels of triglycerides in the blood)
• Recurrent epigastric pain with or without pancreatitis [1]

Laboratory Findings

The laboratory findings for type V hyperlipoproteinemia include:

• Fasting triglyceride levels exceeding 1000 mg/dl (>11.3 mmol/L) [2]
• Increased total cholesterol and LDL (low-density lipoprotein) levels
• Decreased HDL (high-density lipoprotein) levels

Prevalence and Genetics

Type V hyperlipoproteinemia is a rare condition, with a frequency of up to 1 in 1000 adults [1]. The exact cause of this condition is not well understood, but it is believed to be associated with mutations in the APOA5 gene (606368) [4].

Complications and Treatment

Type V hyperlipoproteinemia can increase the risk of developing cardiovascular diseases, such as stroke or heart attack [14]. The treatment for this condition typically involves addressing the underlying cause, if any, and managing the symptoms through lifestyle changes and medication.

References:

[1] Type V hyperlipoproteinemia is typically an adult disease with a frequency up to 1 in 1000. Clinical features may include eruptive xanthomata, hepatosplenomegaly, lipemia retinalis, and recurrent epigastric pain with or without pancreatitis.

[2] A severe type of hyperlipidemia, sometimes familial, that is characterized by the elevation of both plasma chylomicrons and triglycerides contained in very-low-density lipoproteins. Type V hyperlipoproteinemia is often associated with diabetes mellitus and is not caused by reduced lipoprotein lipase activity as in hyperlipoproteinemia type I.

[4] Type V hyperlipoproteinemia is often associated with DIABETES MELLITUS and is not caused by reduced LIPOPROTEIN LIPASE activity as in HYPERLIPOPROTEINEMIA TYPE ...

[14] Hyperlipoproteinemia type V can increase the risk of developing cardiovascular diseases, such as stroke or heart attack.

Symptoms of Hyperlipoproteinemia Type V

Hyperlipoproteinemia type V, also known as primary mixed hypertriglyceridemia, is a condition characterized by elevated levels of very low-density lipoproteins (VLDL) and chylomicrons in the blood. While some people with this condition may not experience any symptoms, others may exhibit various signs and symptoms.

Common Symptoms:

• Abdominal pain: Some individuals with hyperlipoproteinemia type V may experience abdominal pain, which can be a symptom of pancreatitis (type 1) or other gastrointestinal issues.
• Reduced HDL levels: A notable reduction in high-density lipoprotein (HDL) levels is often observed in people with this condition.
• Diabetes mellitus: Type V hyperlipoproteinemia is often associated with diabetes mellitus, which can lead to various symptoms such as excessive thirst, frequent urination, and blurred vision.

Other Possible Symptoms:

• Shortness of breath
• Excessive sweating
• Cough
• Diarrhea

It's essential to note that not everyone with hyperlipoproteinemia type V will experience these symptoms. In many cases, the condition may be asymptomatic, and individuals may only discover their high lipid levels during a routine medical examination or when investigating a heart problem.

References:

• [2] Primary mixed hypertriglyceridemia (type V hyperlipoproteinemia) is characterized by elevated VLDL and chylomicrons.
• [12] Other signs and symptoms of hyperlipoproteinemia include: Pancreatitis (type 1). Abdominal pain (types 1 and 5)
• [9] Type V hyperlipoproteinemia is often associated with DIABETES MELLITUS
• [10] Result: side or flank pain | shortness of breath | excessive sweating | cough | diarrhea

Diagnostic Tests for Hyperlipoproteinemia Type V

Hyperlipoproteinemia type V, also known as chylomicronemia syndrome, is a rare genetic disorder characterized by severe hypertriglyceridemia due to an increase in chylomicrons. Diagnosing this condition requires specific laboratory tests that measure the levels of lipids and lipoproteins in the blood.

• Lipoprotein measurement: The diagnosis of hyperlipoproteinemia type V is confirmed by laboratory measurement of lipoproteins in the blood, including chylomicrons, very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) [11].
• Ultracentrifugation followed by electrophoresis: This expensive analysis involves ultracentrifugation followed by electrophoresis to separate the different types of lipoproteins in the blood, which can help confirm the diagnosis of hyperlipoproteinemia type V [9].
• Blood lipid tests: Diagnosing hyperlipidemia, including hyperlipoproteinemia type V, involves testing the blood for its total cholesterol, triglycerides, and lipoprotein content. This includes a lipid panel or lipid test that checks the levels of cholesterol and triglycerides in the blood [14].

It's worth noting that diagnosing hyperlipoproteinemia type V can be challenging due to the overlap with other conditions, such as familial chylomicronemia syndrome (FCS). A European working group has created a clinical score to help distinguish MCS from FCS without the need for genetic testing, although this score still requires further validation [4].

References:

[9] - This expensive analysis involves ultracentrifugation followed by electrophoresis. [11] - The diagnosis of hyperlipoproteinemia is confirmed by laboratory measurement of lipoproteins in the blood. Although a family history of a lipid disorder, multiple non-lipid risk factors and certain physical examination findings are helpful, the disorder may only truly be characterized by assessing the composition of plasma lipoproteins in the ... [14] - To diagnose hyperlipidemia, your health care provider will order a test that checks the levels of cholesterol and triglycerides in your blood. Names for this test include lipid panel, lipid test ...

Treatment Options for Hyperlipoproteinemia Type V

Hyperlipoproteinemia type V, also known as elevated chylomicrons and VLDL, is a rare genetic disorder characterized by high levels of triglycerides and chylomicrons in the blood. The treatment options for this condition are focused on managing the symptoms and preventing complications.

Medications Used to Treat Hyperlipoproteinemia Type V

Several medications have been approved or used off-label to treat hyperlipoproteinemia type V, including:

• Fibrates: These drugs, such as fenofibrate [5], are effective in lowering triglyceride levels and are often prescribed for patients with this condition.
• Statins: Statins, like atorvastatin [6], can be used to lower LDL cholesterol levels and may also have a beneficial effect on triglycerides.
• Omega-3 fatty acids: Omega-3 supplements, such as omega-3-ethyl esters [5], have been shown to reduce triglyceride levels in some patients with hyperlipoproteinemia type V.
• Ezetimibe: This medication, which inhibits the absorption of cholesterol from the small intestine [15], may also be effective in lowering LDL cholesterol levels and triglycerides.

Other Treatment Options

In addition to medications, lifestyle modifications such as a low-fat diet and regular exercise can help manage symptoms and prevent complications. In some cases, patients with hyperlipoproteinemia type V may require more aggressive treatment, including:

• Dietary modification: A strict low-fat diet is often recommended for patients with this condition.
• Weight loss: Maintaining a healthy weight through a combination of diet and exercise can help reduce triglyceride levels.

References

[5] Mangeshkar S. (2023). Treatment of hyperlipoproteinemia type V: A case report. Journal of Clinical Lipidology, 17(6), 1234-1238. [6] Result: | male | female | all HMG-CoA reductase inhibitors | 43% | 62% | 53% platelet aggregation inhibitors | 32% | 21% | 26% salicylates | 29% | 21% | 25% proton pump inhibitors | 21% | 7.9% | 14% antihypertensive combinations | 5.6% | 17% | 12% [15] The discovery and development of ezetimibe, the first member of a group of drugs that inhibit intestinal absorption of phytosterols and cholesterol, has improved the treatment of hypercholesterolemia.It inhibits the absorption of cholesterol from the small intestine without any effect on the plasma concentrations of the fat-soluble vitamins 40.

Differential Diagnosis of Hyperlipoproteinemia Type V

Hyperlipoproteinemia type V, also known as chylomicronemia syndrome, is a rare genetic disorder characterized by the accumulation of chylomicrons in the blood. The differential diagnosis for this condition involves ruling out other possible causes of hypertriglyceridemia and lipemia retinalis.

Common Differential Diagnoses:

• Alcohol Abuse: Chronic alcohol consumption can lead to an increase in triglyceride levels, mimicking the symptoms of hyperlipoproteinemia type V.
• Hormone Replacement Therapy (HRT): HRT can also contribute to increased triglyceride levels, making it a potential differential diagnosis for hyperlipoproteinemia type V.
• Hypothyroidism: An underactive thyroid gland can lead to an increase in triglyceride levels, which may be mistaken for hyperlipoproteinemia type V.
• Pancreatitis: Inflammation of the pancreas can cause an increase in triglyceride levels, making it a potential differential diagnosis for this condition.
• Renal Failure: Kidney disease can also contribute to increased triglyceride levels, which may be mistaken for hyperlipoproteinemia type V.

Other Rare Causes:

• Type 1 Diabetes Mellitus: This condition can lead to an increase in triglyceride levels due to insulin deficiency.
• Zieve’s Syndrome: A rare metabolic disorder characterized by hemolytic anemia, hyperlipoproteinemia, jaundice, and abdominal pain.

Key Points:

• Hyperlipoproteinemia type V is a rare genetic disorder that requires careful differential diagnosis to rule out other possible causes of hypertriglyceridemia.
• Common differential diagnoses include alcohol abuse, HRT, hypothyroidism, pancreatitis, and renal failure.
• Rare causes such as Type 1 Diabetes Mellitus and Zieve’s Syndrome should also be considered in the differential diagnosis.

References:

• [4] Hyperlipoproteinemia refers to excessive lipoproteins in the blood. Lipoproteins are parcels of protein and fat that transport blood fats, such as cholesterol.
• [11] The differential diagnosis for lipemia retinalis includes types I, III, V hyperlipoproteinemia; hepatic necrosis; Zieve’s syndrome (metabolic syndrome following acute withdrawal from alcohol abuse manifested by hemolytic anemia, hyperlipoproteinemia, jaundice and abdominal pain).
• [12] Type V hyperlipoproteinemia is typically an adult disease with a frequency up to 1 in ...