The number of trichinella larvae in a muscle biopsy can be graded based on the tissue density.
Method:
(1) A muscle biopsy is collected and weighed accurately.
(2) The tissue is digested with enzymes and the number of larvae counted.
Number of Larvae per gram of tissue |
Degree of Tissue Invasion |
< 1 |
very light |
1 - 50 |
light |
51 - 100 |
moderate |
101 - 500 |
severe |
501 - 1,000 |
very severe |
> 1,000 |
lethal |
after Table I, page 135
Limitations:
• The parasitic load may not correlate with clinical symptoms, especially in patients with marked allergic response to the larvae.
• The number of larvae may vary between different muscle groups so that there is sampling bias.
• The size of a biopsy and the number taken in a living patient is limited.
• Patients with high larval density may recover without complications.
Specialty: Infectious Diseases