Urine 24 hours for VMA

Sample Urine 24 hours for VMA

1. The test is done in the urine.
2. Collect 24 hours urine samples.
   1. Discard the first urine sample and not the time. Now collect all urine samples in the container containing 6 mL of HCl. Collect the last sample when 24 hours are completed.
   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.

Precautions Urine 24 hours for VMA

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

Purpose of the test (Indications) for Urine 24 hours for VMA

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

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 has 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.

Normal

Source 1

VMA 

Age	mg/day
0 to 10 day	<1.0
10 days to 24 months	<2.0
24 months to 18 years	<5.0
Adult	2.1 to 7.6

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

Test	Urine sample	Plasma
VMA	up to 9 mg/24 hours
VMA Some reference says	2.1 to 7.6 mg/24 hours
Catecholamines total	<100 µg/ 24 hours
Epinephrine	0 to 20 µg/ 24 hours	<50 pg/mL
Metanephrine	74 to 297 µg/ 24 hours
Norepinephrine	15 to 80 µg/ 24 hours	110 to 410 pg/mL
Dopamine	65 to 400 µg/ 24 hours	<87 pg/mL

Neuroblastoma

Definition of 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).

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 an 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.

Diagnosis of Neuroblastoma:

1. Biopsy with immunocytochemistry.
2. Bone marrow for the presence of cancer cells.
3. Increased blood or urine level of catecholamines metabolites like:
   1. VMA.
   2. HVA (homovanilic acid).
   3. Urinary measurement is preferred.
   4. At the time of 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.

Type of the test	Value of the test
Catecholamines	Increased
Vanillylmandelic acid (VMA)	Increased
Homovanilic acid (HVA)	Increased
Dopamine	Increased
Metanephrines	Increased

Treatment of Neuroblastoma:

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

Increased VMA level is seen in:

1. Adrenal glands 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.

Decreased VMA level is seen in:

1. In Diabetes
2. Parkinsonism.

Increased Catecholamine is seen in:

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

Decreased Catecholamine is seen in:

1. Parkinsonism.
2. Diabetic neuropathy.

Normal urine picture:

Physical features	Chemical features	Microscopic findings
Color = Pale yellow or amber Appearance = Clear to slightly hazy pH = 4.5 to 8.0 Specific gravity = 1.015 to 1.025	Blood = Negative Glucose = Negative Ketones= Negative Protein = Negative Bilirubin = Negative Urobilinogen = Negative (±) Leucocyte esterase = Negative Nitrite for bacteria = Negative	RBCs = Rare or Negative WBC = Rare or Negative Epithelial cells = Few Cast = Negative (Occasional hyaline) Crystal = Negative (Depends upon the pH of the urine) Bacteria = Negative

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