Summary about Disease
Insulinoma is a rare tumor of the pancreas that causes it to produce too much insulin. This excess insulin leads to hypoglycemia (low blood sugar), which can cause a variety of symptoms. Insulinomas are usually benign (non-cancerous), but they can cause significant health problems if left untreated.
Symptoms
Symptoms of insulinoma are primarily related to hypoglycemia and can vary in severity. They may include:
Sweating
Tremors
Palpitations (rapid heartbeat)
Anxiety
Hunger
Confusion
Blurred vision
Dizziness
Weakness
Seizures
Loss of consciousness Symptoms often occur after fasting, exercise, or when meals are delayed.
Causes
The cause of insulinoma is generally unknown. It develops when pancreatic beta cells, which produce insulin, develop into a tumor. This tumor then secretes excessive amounts of insulin, leading to hypoglycemia. Insulinomas are typically sporadic, meaning they occur randomly and are not inherited. Rare genetic syndromes, such as Multiple Endocrine Neoplasia type 1 (MEN1), can increase the risk of developing insulinoma.
Medicine Used
Diazoxide: This medication inhibits insulin release from the tumor. It is often used to manage symptoms while awaiting surgery or if surgery is not an option.
Octreotide: A somatostatin analog that can suppress insulin secretion in some cases. It is more effective in specific types of insulinomas.
Glucose: Administered intravenously or orally to raise blood sugar levels during hypoglycemic episodes.
Chemotherapy: In rare cases where the insulinoma is malignant and has spread, chemotherapy may be used.
Everolimus: In cases of unresectable or metastatic insulinoma, this mTOR inhibitor may be considered.
Is Communicable
No, insulinoma is not a communicable disease. It is not caused by an infection and cannot be spread from person to person.
Precautions
Precautions focus on managing hypoglycemia and include:
Frequent meals and snacks: Eating regularly, especially before exercise or long intervals between meals, helps prevent low blood sugar.
Carry a source of fast-acting glucose: Glucose tablets, hard candy, or juice can quickly raise blood sugar levels during a hypoglycemic episode.
Medical alert identification: Wear a medical alert bracelet or necklace to inform others of your condition in case of an emergency.
Monitor blood sugar levels: Regular blood glucose monitoring helps identify and manage hypoglycemia.
Inform family and friends: Educate close contacts about the symptoms of hypoglycemia and how to administer glucagon if you become unconscious.
How long does an outbreak last?
Insulinoma doesn't have "outbreaks" in the traditional sense like an infectious disease. The symptoms related to hypoglycemia will continue as long as the tumor continues to produce excessive insulin. Without treatment (usually surgery), symptoms will persist.
How is it diagnosed?
Fasting Blood Glucose Test: This test measures blood glucose levels after a period of fasting (typically overnight or longer). In individuals with insulinoma, blood glucose levels will be low during fasting.
Insulin and Proinsulin Levels: Blood tests to measure insulin and proinsulin levels. Insulinomas often cause elevated insulin and proinsulin levels, even when blood glucose is low.
C-peptide Level: A blood test to measure C-peptide, a substance produced when insulin is made. Elevated C-peptide levels indicate that the body is producing too much insulin.
Imaging Studies: CT scans, MRI scans, or endoscopic ultrasound (EUS) can help locate the tumor in the pancreas.
Calcium Stimulation Test: In some cases, a calcium stimulation test may be performed. Calcium is injected into a vein, and insulin levels are measured. Insulinomas typically respond to calcium stimulation with a significant increase in insulin release.
Timeline of Symptoms
The timeline of symptoms varies greatly from person to person.
Early Stages: Mild symptoms like sweating, tremors, and anxiety might be infrequent and easily dismissed.
Progression: As the tumor grows, symptoms become more frequent and severe, including confusion, blurred vision, and dizziness. These episodes are triggered by low blood sugar.
Late Stages: If untreated, severe hypoglycemia can lead to seizures, loss of consciousness, and brain damage. The frequency and severity of these episodes increase over time.
Important Considerations
Surgery is the primary treatment: Surgical removal of the insulinoma is often curative, especially if the tumor is benign and localized.
Hypoglycemia unawareness: Some people with insulinoma may develop hypoglycemia unawareness, where they no longer experience the early warning signs of low blood sugar. This can be dangerous.
Differential Diagnosis: It's essential to rule out other causes of hypoglycemia, such as diabetes medications, other medical conditions, or reactive hypoglycemia.
Malignant Insulinoma: Although rare, insulinomas can be malignant (cancerous). Regular follow-up is necessary to monitor for recurrence or metastasis.
Specialist Care: Management of insulinoma requires the expertise of endocrinologists and surgeons experienced in pancreatic disorders.