Urine 24 hours for VMA (Vanillylmandelic acid), Catecholamines (24 hours urine), Neuroblastoma

Sample

1. The test is done in the urine.
2. Collect 24 hours urine sample.
   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 is stable for 2 weeks.
4. The sample is stable for 2 weeks at 2 to 4 °C.

Precautions

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)

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

Pathophysiology

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 concentration 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.

Neuroblastoma

1. Signs and symptoms:
   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.
2. Due to increased catecholamines from the adrenal medulla, there are:
   1. Hypertension.
   2. Rapid heartbeat.
   3. Diarrhea.
   4. Before the tumor is diagnosed, there is already spread to lymph nodes, liver, lungs, bone, and bone marrow.
3. Diagnosed by:
   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. Radiology like CT or MRI.
4. Treatment:
   1. Surgery.
   2. Radiation.
   3. Chemotherapy.
   4. Bone marrow transplantation.

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

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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