Technetium Tc 99m Albumin Colloid (Systemic)


VA CLASSIFICATION
Primary: DX201

Commonly used brand name(s): Microlite.

Note: For a listing of dosage forms and brand names by country availability, see Dosage Forms section(s).

Not commercially available in Canada.



Category:


Diagnostic aid, radioactive (hepatic disease; hematologic disease; splenic disease)—

Indications

Accepted

Liver imaging, radionuclide—Technetium Tc 99m albumin colloid, administered intravenously, is indicated for imaging the functioning reticuloendothelial cells of the liver in the evaluation of metastatic disease, primary liver tumors, abscesses, and other focal hepatic lesions. It is also indicated in the evaluation of patients with cirrhosis, hepatitis, and other hepatic disorders. {01} {02} {16} {19} {20}

Spleen imaging, radionuclide—Technetium Tc 99m albumin colloid, administered intravenously, is indicated for imaging the functioning reticuloendothelial cells of the spleen, thus serving to demonstrate clinically significant splenomegaly, and for evaluating splenic infarct or splenic rupture. {01} {02} {16} {19} {20}

Bone marrow imaging, radionuclide—Technetium Tc 99m albumin colloid, administered intravenously, is indicated for imaging the functioning reticuloendothelial cells of the bone marrow to complement other hematological studies for the evaluation of hematopoiesis in hematological diseases, such as leukemia, polycythemia, anemias, and myelofibrosis. Also, imaging with technetium Tc 99m albumin colloid helps localize sites for bone marrow biopsy and helps demonstrate or define areas of marrow invasion by metastatic disease and areas of decreased marrow function secondary to radiation therapy. {01} {02} {16}


Physical Properties

Nuclear data {01}:



Radionuclide
(half-life)
Decay
constant
Mode
of
decay
Principal
photon
emissions
(keV)
Mean
number of
emissions/
disintegration
(³0.01)
Tc 99m
(6.0 hr)
0.1151 h -1
Isomeric transition to Tc 99
Gamma
(18)
0.062
Gamma
(140.5)
0.891


Pharmacology/Pharmacokinetics

Mechanism of action/Effect:

Diagnostic aid (hepatic disease; hematologic disease; splenic disease)—Radioactive colloids are phagocytized by the reticuloendothelial system of the liver, spleen, and bone marrow, and remain there long enough for scintillation scans of their distribution to be obtained. {16}

Distribution:

The colloid particles are rapidly phagocytized by the reticuloendothelial system after intravenous administration. Distribution is dependent upon blood flow rates and the functional capacity of the phagocytic cells. In the average normal patient, 80 to 90% of the administered activity localizes in the liver, 5 to 10% in the spleen, and the remainder in bone marrow. Levels of activity in the liver and spleen remain constant for at least 4 hours. {01} {04} {16}

Uptake in the lungs and other soft tissues is possible in the presence of a wide variety of disorders, usually inflammatory or neoplastic. {01} {16}

Note: In progressively severe hepatic dysfunction (e.g., hepatic cirrhosis), greater amounts of the colloid appear in the spleen, bone marrow, and sometimes, in the lungs. {18}


Half-life:

Elimination from the blood pool—2 to 3 minutes. {16}

Time to radioactivity visualization:

Liver and spleen imaging—10 to 15 minutes. {16}

Note: In patients with severe hepatic disease, onset of visualization may be delayed because of slower blood clearance of the colloid. {16}



Bone marrow imaging—15 minutes. {16}


Radiation dosimetry:
{11}

Organ
Estimated absorbed radiation dose*
With normal
hepatic function


With parenchymal
liver disease
(intermediate/advanced)

mGy/
MBq
rad/
mCi
mGy/
MBq
rad/
mCi
Spleen
0.077
0.29
0.14
0.52
Liver
0.074
0.27
0.042
0.16
Pancreas
0.012
0.044
0.018
0.066
Red marrow
0.011
0.041
0.023
0.085
Adrenals
0.01
0.037
0.0098
0.036
Kidneys
0.0097
0.036
0.011
0.041
Bone surfaces
0.0064
0.024
0.012
0.044
Stomach wall
0.0062
0.023
0.0098
0.036
Large intestine
wall (upper)

0.0056

0.021

0.0049

0.018
Lungs
0.0055
0.20
0.0048
0.018
Small intestine
0.0043
0.016
0.0046
0.017
Breast
0.0027
0.01
0.0024
0.0089
Ovaries
0.0022
0.0081
0.0033
0.012
Uterus
0.0019
0.0070
0.0028
0.01
Large intestine
wall (lower)

0.0018

0.0067

0.0031

0.011
Bladder wall
0.0011
0.0041
0.0016
0.0059
Thyroid
0.00079
0.0029
0.0011
0.0041
Testes
0.00062
0.0023
0.00095
0.0035
Other tissue
0.0028
0.01
0.0031
0.011


Radionuclide
Effective dose*
With normal
hepatic function


With parenchymal
liver disease
(intermediate/advanced)

mSv/
MBq
rem/
mCi
mSv/
MBq
rem/
mCi
Tc 99m
0.014
0.052
0.017
0.063
* For adults; intravenous injection of technetium Tc 99m–labeled large colloids. Data based on the International Commission on Radiological Protection (ICRP) Publication 53—Radiation dose to patients from radiopharmaceuticals. {11}

Elimination:
    Renal, 4 to 30% of the administered activity is eliminated by 24 hours after injection. {01} {16}


Precautions to Consider

Cross-sensitivity and/or related problems

Patients sensitive to human serum albumin products may be sensitive to this radiopharmaceutical also. {01}

Carcinogenicity/Mutagenicity

Long-term animal studies to evaluate carcinogenic or mutagenic potential of technetium Tc 99m albumin colloid have not been performed. {01}

Pregnancy/Reproduction

Pregnancy—
Tc 99m (as free pertechnetate) crosses the placenta. Studies with technetium Tc 99m albumin colloid have not been done in humans.

The possibility of pregnancy should be assessed in women of child-bearing potential. Clinical situations exist in which the benefit to the patient and fetus, based on information derived from radiopharmaceutical use, outweighs the risks from fetal exposure to radiation. In these situations, the physician should use discretion and reduce the radiopharmaceutical dose to the lowest possible amount. {07} {08}

Studies have not been done in animals.

FDA Pregnancy Category C. {01}

Breast-feeding

Although it is not known whether technetium Tc 99m albumin colloid is distributed into breast milk, it is known that Tc 99m as free pertechnetate is distributed into breast milk. Based on the assumption that the Tc 99m in breast milk is in the form of pertechnetate and based on the effective half-life of the radionuclide in breast milk, the daily volume of milk, a dose factor relating the radionuclide to its critical organ (thyroid) in the nursing infant, and the maximum permissible dose to that organ, a guideline has been proposed. According to this guideline, it has been calculated that nursing can be safely resumed when the concentration in breast milk reaches 30.3 × 10 -4 megabecquerels (8.2 × 10 -2 microcuries) per mL. This level of activity is probably reached, in the majority of patients, within 12 to 24 hours after administration of technetium Tc 99m–labeled radiopharmaceuticals. {10} {13}

Pediatrics

Diagnostic studies performed to date using technetium Tc 99 albumin colloid have not demonstrated pediatrics-specific problems that would limit the usefulness of technetium Tc 99m albumin colloid in children. However, when this radiopharmaceutical is used in children, the diagnostic benefit should be judged to outweigh the potential risk of radiation. {08}


Geriatrics


Appropriate studies on the relationship of age to the effects of technetium Tc 99m albumin colloid have not been performed in the geriatric population. However, no geriatrics-specific problems have been documented to date.

Drug interactions and/or related problems
See Diagnostic interference.

Diagnostic interference
The following have been selected on the basis of their potential clinical significance (possible effect in parentheses where appropriate)—not necessarily inclusive (» = major clinical significance):

With results of this test

Due to other medications
Anesthetics, inhalation, such as halothane    (recent administration of general anesthetics may increase splenic uptake of technetium Tc 99m albumin colloid, probably because the reduced hepatic flow and hepatotoxicity associated with general anesthetics may alter the hepatic radiocolloid extraction efficiency, resulting in an alteration of the normal liver-spleen colloid distribution pattern {15})


Chemotherapy, especially with nitrosoureas    (use of technetium Tc 99m albumin colloid in patients who are undergoing or have recently undergone chemotherapy may result in nonhomogeneous or irregular hepatic uptake, shift of activity from the liver to the bone marrow and spleen, and hepatomegaly; irregular hepatic distribution of radiopharmaceutical may be misinterpreted as malignancy; thus, it is recommended that liver and/or spleen imaging be done prior to initiating chemotherapy with these agents or several weeks after discontinuing therapy {03} {05} {09} {12} {16})


Reticuloendothelial system stimulators, such as:
Dextrose{15}
Heparin{15}
Steroid hormones (including estrogen){16}
Thyroid hormones{15}
Vitamin B 12{15}    (use of technetium Tc 99m albumin colloid in patients using these medications may result in lung uptake of technetium Tc 99m albumin colloid, probably due to a drug-induced increase in number of free intravascular macrophages, which may migrate to the pulmonary capillary bed and phagocytize colloidal particles there {15} {16})


Due to medical problems or conditions
Viral infections    (decreased function of the reticuloendothelial system caused by the viral infection may result in prolonged appearance of the technetium Tc 99m albumin colloid in the blood {16})


Medical considerations/Contraindications
The medical considerations/contraindications included have been selected on the basis of their potential clinical significance (reasons given in parentheses where appropriate)— not necessarily inclusive (» = major clinical significance).

See also Diagnostic interference .

Risk-benefit should be considered when the following medical problem exists
» Sensitivity to human serum albumin or to the radiopharmaceutical preparation{01}


Side/Adverse Effects
The following side/adverse effects have been selected on the basis of their potential clinical significance and/or frequency of occurrence (possible signs and symptoms in parentheses where appropriate)—not necessarily inclusive:

Those indicating need for medical attention
Incidence less frequent or rare
    
Allergic reaction{01}{14} (coughing or choking; flushing or redness of face; skin rash, hives, or itching; swelling of throat, hands, or feet; wheezing, tightness in chest, or troubled breathing)
Note: The allergic reaction may be the initial manifestation of a more severe anaphylactic reaction. {01} {14}





Those indicating need for medical attention only if they continue or are bothersome
Incidence less frequent
    
Abdominal pain {01}
    
dizziness {01}
    
fever {01}
    
flushing of skin {01}
    
increased sweating {01}
    
nausea {01}





Patient Consultation
As an aid to patient consultation, refer to Advice for the Patient, Radiopharmaceuticals (Diagnostic).

In providing consultation, consider emphasizing the following selected information (» = major clinical significance):

Description of use
Action in the body: Accumulation of radioactive colloid particles in liver, spleen, and bone marrow

Retention of radioactivity in these organs allows visualization

Small amounts of radioactivity used in diagnosis; radiation received is low and considered safe

Before having this test
»   Conditions affecting use, especially:
Sensitivity to albumin products or to the radiopharmaceutical preparation

Pregnancy—Technetium Tc 99m (as free pertechnetate) crosses placenta; risk to fetus from radiation exposure as opposed to benefit derived from use should be considered





Breast-feeding—Not known if technetium Tc 99m albumin colloid is distributed into breast milk, but Tc 99m as free pertechnetate is distributed into breast milk; temporary discontinuation of nursing may be recommended because of risk to infant from radiation exposure





Use in children—Risk from radiation exposure as opposed to benefit derived from use should be considered


Preparation for this test
Special preparatory instructions may be given; patient should inquire in advance

Precautions after having this test
No special precautions


Side/adverse effects
Signs of potential side effects, especially allergic reaction


General Dosing Information
Radiopharmaceuticals are to be administered only by or under the supervision of physicians who have had extensive training in the safe use and handling of radioactive materials and who are authorized by the Nuclear Regulatory Commission (NRC) or the appropriate Agreement State agency if required, or, outside the U.S., the appropriate authority.

Technetium Tc 99m albumin colloid should be administered by intravenous injection and, preferably, with the patient in a recumbent position (in the erect position the liver may appear larger). During injection, the aspiration of blood into the syringe should be avoided since this can cause the formation of blood clots (containing the radioactive material) in the syringe, which may result in focal areas of increased radioactivity during lung imaging. {06} {16}

Epinephrine, antihistamines, and corticosteroids should be available during the administration of technetium Tc 99m albumin colloid because of the possibility of allergic reactions. {01}

Safety considerations for handling this radiopharmaceutical
Improper handling of this radiopharmaceutical may cause radioactive contamination. Guidelines for handling radioactive material have been prepared by scientific, professional, state, federal, and international bodies and are available to the specially qualified and authorized users who have access to radiopharmaceuticals. {21}


Parenteral Dosage Forms

TECHNETIUM Tc 99m ALBUMIN COLLOID INJECTION

Usual adult and adolescent administered activity
Liver, spleen, and/or bone marrow imaging
Intravenous, 37 to 296 megabecquerels (1 to 8 millicuries). {01}

Note: For bone marrow imaging, 370 to 444 megabecquerels (10 to 12 millicuries) are usually required. {16}



Usual pediatric administered activity
Dosage must be individualized by physician.


Liver and spleen imaging:
Activity administered has ranged between 0.55 and 2.75 megabecquerels (15 to 75 microcuries) per kg of body weight, with a usual administered activity of 1.8 megabecquerels (50 microcuries) per kg of body weight. {16}

Note: In newborns, the total minimum administered activity recommended for liver and spleen imaging is 11.1 to 18.5 megabecquerels (300 to 500 microcuries). {16}




Bone marrow imaging:
A dosage of 5.18 megabecquerels (140 microcuries) per kg of body weight is recommended. {17}


Usual geriatric administered activity
See Usual adult and adolescent administered activity .

Strength(s) usually available
U.S.—


1 mg albumin colloid, 10 mg normal human serum albumin, 0.0054 mg stannous chloride (minimum), 0.17 mg total tin (maximum), 1.1 mg poloxamer 188, 0.12 mg medronate disodium, and 10 mg sodium phosphate (anhydrous), per reaction vial (Rx) [Microlite]

Canada—
Not commercially available.

Packaging and storage:
Store between 2 and 8 °C (36 and 46 °F). Protect from freezing. Protect from light. {01}

Preparation of dosage form:
To prepare injection, an oxidant-free sodium pertechnetate Tc 99m solution is used. See manufacturer's package insert for instructions. {01}

Stability:
Preparations in which clumping of contents are observed should not be used. {01}

Injection should be administered within 6 hours after preparation. {01}

Incompatibilities:
If oxidants such as peroxides and hypochlorites are present in the sodium pertechnetate Tc 99m used for labeling, the final preparation may be adversely affected and should be discarded. {01}

Note: Caution—Radioactive material.
Agitate gently before using.




Developed: 08/17/1994



References
  1. Microlite package insert (Du Pont—US), Rev 11/91.
  1. Chilton HM, Witcofski RL. Nuclear pharmacy—An introduction to the clinical application of radiopharmaceuticals. Philadelphia: Lea & Febiger, 1986: 103-4.
  1. Geronemus RG, Auerbach R, Tobias H. Liver biopsies vs liver scans in methotrexate-treated patients with psoriasis. Arch Dermatol 1982; 118: 649-51.
  1. Saba TM. Physiology and physiopathology of the reticuloendothelial system. Arch Intern Med 1970; 126: 1031-50.
  1. Kaplan WD, Drum DE, Lockich JJ. The effect of cancer chemotherapy agents on the liver-spleen scan. J Nucl Med 1980; 21: 84-7.
  1. Jackson ML, Zuckier L, Goldfarb CR, et al. Effect of patient positioning on liver size. J Nucl Med 1986; 27: 1632-4.
  1. USP Radiopharmaceutical Advisory Panel meeting, 1/88.
  1. USP Radiopharmaceuticals Advisory Panel meeting, 8/4/92.
  1. Hladik WB, Saha GB, Study KT. Essentials of nuclear medicine science. Baltimore: Williams & Wilkins, 1987: 190.
  1. Mountford PJ, Coakley AJ. A review of the secretion of radioactivity in human breast milk: data, quantitative analysis and recommendations. Nucl Med Commun 1989; 10: 15-27.
  1. Task Group of Committee 2 of the International Commission on Radiological Protection. Annals of the ICRP. ICRP Publication 53—Radiation dose to patients from radiopharmaceuticals. New York: Pergamon Press, 1988: 43.
  1. Reviewers' responses to technetium Tc 99m sulfur colloid monograph revision of 5/94.
  1. Ahlgren L, Ivarsson S, Johansson L, et al. Excretion of radionuclides in human breast milk after the administration of radiopharmaceuticals. J Nucl Med 1985; 26(9): 1085-90.
  1. Gals BJ, Erstad BL. Adverse reactions to human serum albumin. Ann Pharmacother 1993; 27: 87-94.
  1. Laven DL, Clanton JA, Hladik WB, et al. Pharmacologic alterations in the biorouting/performance of radiopharmaceuticals used in nuclear medicine adrenal, cerebral, hepatobiliary, pulmonary and renal scintigraphic studies. Bay Pines, FL: Gammascan Consultants.
  1. Swanson DP, Chilton HM, Thrall JH, editors. Pharmaceuticals in medical imaging. New York: Macmillan Publishing Company, 1990: 464-70; 555.
  1. Pediatric dosages recommended by USP Radiopharmaceuticals Advisory panelists 1992.
  1. Reviewers' comments per 5/9/94 monograph revision.
  1. Klingensmith WC, Spitzer VM, Fritzberg AR, et al. Normal appearance and reproducibility of liver-spleen studies with Tc 99m sulfur colloid and Tc 99m microalbumin colloid. J Nucl Med 1983; 24: 8-13.
  1. Saha GB, Feiglin DHI, O'Donnell JK, et al. Experience with technetium Tc 99m albumin colloid kit for reticuloendothelial system imaging. J Nucl Med Technol 1986; 14: 149-51.
  1. Reviewers' responses to Radiopharmaceuticals Advisory Panel Ballot of 5/11/94.
Hide
(web1)