Urine 24 hours for VMA

What sample is needed for Urine 24 hours for VMA?

1. The test is done in the urine.
2. Collect 24-hour urine samples.
   1. Discard the first urine sample and note the time. Now, collect all urine samples in the container containing 6 mL of HCl. Collect the last sample when 24 hours have passed.
   2. Or add 20 mL of HCL (6 mol/L)
3. Refrigerate the urine during collection, and it is stable for 2 weeks.
4. The sample is stable for 2 weeks at 2 to 4 °C.

What are the precautions for Urine 24-hour VMA?

1. Following foods and drugs cause the false raised level of VMA.
   1. Avoid chocolate, coffee, tea, and cocoa for 2 to 3 days before the test is performed.
   2. Avoid foods like citrus fruits, bananas, and vanilla food.
   3. Avoid beer and red wine.
   4. Avoid drugs like aspirin and antihypertensive medicines.
2. Vigorous exercise and stress may increase the VMA level.
3. Decreased VMA levels may be seen in patients with uremia, alkaline urine, and radiographic contrast media.
4. Drugs that may increase the level are levodopa, lithium, nitroglycerine, epinephrine, and caffeine.
5. Drugs that may decrease the level are phenothiazine, reserpine, guanethidine, monoamine oxidase inhibitor, and disulfiram.

What are the Indications for Urine 24 hours for VMA?

1. To diagnose pheochromocytoma.
2. For Tumors of the adrenal medulla.
3. To diagnose neuroblastoma.
4. In patients with hypertension.

How will you discuss the pathophysiology of Urine 24 hours for VMA?

1. The catecholamines are formed from the precursor Tyrosine with the action of different enzymes.

2. The Adrenal Gland makes a lot of catecholamines as a reaction to stress.
3. The end product of catecholamines is VMA excreted in the urine.
4. 3-methoxy-4-hydroxymandelic acid is also called VMA.
5. The main catecholamines are:
   1. Epinephrine.
   2. Adrenaline.
   3. Norepinephrine (Noradrenaline).
   4. Dopamine.

6. Catecholamines break down into VMA + Metanephrine, which is excreted in the urine.

7. VMA is 10 to 100 times more concentrated in the urine than other amines.
8. Increased catecholamine is found in the patient with:
   1. Fall in blood pressure (Decreased blood volume).
   2. Thyroid hormone deficiency.
   3. Congestive heart failure.
   4. Arrhythmias.
9. Decreased level of catecholamines seen in a patient with idiopathic postural hypotension.

What are the normal values of the VMA?

Source 1

VMA 

Source 2

• Adult/elderly = <6.8 mg/24 hours
• Adolescent = 1 to 5 mg/24 hours
• Child     =  1 to 3 mg/24 hours
• Infants = <2 mg/24 hours
• Newborn = <1 mg/24 hours

Other sources

Neuroblastoma

How will you define Neuroblastoma?

1. Neuroblastoma is a neural crest tumor like pheochromocytoma arising from the adrenal gland or sympathetic chain.
2. Neuroblastoma is the second most common extracranial, nonhematological neoplasm of childhood between the ages of 1 to 4 years.
3. Neuroblastoma is the most common abdominal malignant mass except Wilm’s tumor.
4. Catecholamines include norepinephrine, normetanephrine, dopamine, VMA, and HVA (all are increased).

What are the signs and symptoms of Neuroblastoma?

1. Most common tumors of children under the age of 5 years.
2. It arises anywhere along with the sympathetic nervous system.
3. A common site is the adrenal medulla.
4. Neuroblastoma diagnosed in the first year of life has a better prognosis.
5. Due to increased catecholamines from the adrenal medulla, there are:
   1. Hypertension.
   2. Rapid heartbeat.
   3. Diarrhea.
6. Before the tumor is diagnosed, there is already spread to lymph nodes, liver, lungs, bone, and bone marrow.
7. 70% of the cases have metastasis at the time of diagnosis.

How will you diagnose Neuroblastoma?

1. Biopsy with immunocytochemistry.
2. Bone marrow for the presence of cancer cells.
3. Increased blood or urine levels of catecholamine metabolites like:
   1. VMA.
   2. HVA (homovanilic acid).
   3. Urinary measurement is preferred.
   4. At diagnosis, 90% have increased HVA, and 75% have increased VMA.
   5. Screening for catecholamines at 6 months can diagnose Neuroblastoma.
4. Radiology like CT or MRI.

How will you summarize the diagnostic tests for Neuroblastoma?

How will you treat Neuroblastoma?

1. Surgery.
2. Radiation.
3. Chemotherapy.
4. Bone marrow transplantation.
5. Treatment by a combination of radiation and chemotherapy gives good results.

What are the causes of increased VMA levels?

1. Adrenal gland tumor (Pheochromocytoma)
2. It May be seen in any major stress like:
   1. Burns.
   2. Body infections ( sepsis).
   3. Surgery or traumatic injury.
3. Many blood pressure drugs.
4. Neuroblastoma.
5. Ganglioblastoma.
6. Ganglioneuroma.
7. Carcinoid tumors.

What are the causes of decreased VMA levels?

1. In Diabetes
2. Parkinsonism.

What are the causes of increased Catecholamine?

1. Pheochromocytoma.
2. Neuroblastoma.
3. Ganglioneuroma.
4. Diabetic acidosis.
5. Hypothyroidism.
6. Myocardial infarction.

What are the causes of decreased Catecholamine?

1. Parkinsonism.
2. Diabetic neuropathy.

What is the difference between Neuroblastoma and Pheochromocytoma?

Questions and answers?