HISTOLOGICAL COMPARISON OF HUMAN THYMUS GLANDS BETWEEN GROUPS OF DIFFERENT AGES

Histological Comparison of Human Thymus Gland

Abstract

Objective: To compare the thickness of the capsule and interlobular connective tissue, and number and diameter of Hassal's corpuscles in human thymus between two groups of young and old patients.

Study Design: Comparative study.

Place and Duration of Study: The study was carried out in the Anatomy Department at Army Medical College Rawalpindi from Sep 2007 to Oct 2007.

Material and Methods: Forty specimens of human thymus were separated into two groups: Group A included 20 specimens from patients between 1-25 years while Group B had same number of specimens of more than 40 years of age. These specimens were fixed in 10% formalin solution and then processed for paraffin embedding. Five micron thick sections were made. Haematoxylin and eosin stain, and PAS stain were used. The thickness of thymic capsule and interlobular connective tissue, number and diameter of Hassal's corpuscles in both groups were noted.

Results: Statistically significant differences were found in the thickness of capsule and interlobular connective tissue, number and size of Hassal's corpuscles in specimens of different age groups.

Conclusion: In old age, there is definite increase in the thicknesses of capsule and interlobular connective tissue with Hassal's corpuscles decreasing in number but increasing in diameter.