Development of spleen and suprarenal glands

Spleen

Origin: Mesodermal cells in dorsal mesogastrium

  • These cells will form stroma and capsule
  • Hematopoietic cells infiltrate spleen
  • Dorsal mesogastrium forms: gastrosplenic ligament and splenorenal ligament

NB: Hematopoietic function lost with embryo development. Lymphoid precursor cells migrate into developing organ

development of spleen

Congenital anomalies:

  1. Accessory spleen
  2. Wandering spleen – lacks one ligament or both
  3. Polysplenia/ Chaudhrey’s disease – multiple small accessory spleens

Suprarenal glands

  • Cortex – Mesodermal cells of intraembryonic coelomic epithelium
  • On either side of mesentery of gut, proliferates to form fetal cortex
  • Medulla – Sympatho – chromaffin cells from neural crest cells (ectoderm)
  • Migrate to enter medial aspect of fetal cortex
  • Second layer of cells develop from coelomic mesothelium and surrounds fetal cortex to form permanent cortex
  • Fetal cortex regresses and disappears after 3rd year of birth
  • Permanent cortex differentiates into 3 zones: zona glomerulosa, zona fasiculata and zona reticularis. Complete histological differentiation attained at puberty.
Image result for development of suprarenal gland

Congenital anomalies:

  1. Agenesis
  2. Ectopic suprarenal gland – below capsule of kidney
  3. Accessory cortical tissue – found on posterior abdominal wall and pelvis
  4. Adrenogenital syndrome – hypertrophy of suprarenal cortex and over production of androgens. Results of pseudohermaphroditism in females and premature enlargement of external genitalia in males