Hyaline change (hyalinosis)
Why some tissues turn glassy and pink: hyaline as an appearance, not one substance, and its main forms, from thickened arterioles in hypertension and diabetes to hyaline membranes in injured lungs, with the harm each does.
By the end, you can
- Explain why "hyaline" describes an appearance shared by different materials, inside and outside cells.
- Describe how long-standing hypertension and diabetes produce hyaline arteriolosclerosis, and its effect on the kidney.
- Relate the hyaline nodules and thick basement membranes of diabetic glomeruli to albumin in the urine.
- Explain how hyaline membranes form in injured alveoli and why they impair gas exchange.
- Distinguish hyaline change from amyloid and fibrinoid necrosis.
- Recognise the classic forms of intracellular and extracellular hyaline and the tests that reveal them, and explain how blood pressure and glucose control, angiotensin blockade, surfactant and lung-protective ventilation act on the mechanism.
What it is
Hyaline describes any material that looks homogeneous, glassy and pink with haematoxylin and eosin. It is a descriptive term, not one substance: plasma proteins, basement membrane material, fibrin, dense collagen and some intracellular proteins can all look hyaline. Hyalinosis usually means extracellular hyaline in the walls of small vessels and in connective tissue; intracellular hyaline includes Russell bodies, reabsorption droplets and Mallory–Denk bodies.
4 types to tell apart
- Vascular hyalinosis
- Hyaline arteriolosclerosis: glassy thickening of arteriole walls in long-standing hypertension, diabetes and older age.
- Connective tissue hyalinisation
- Old scars, obsolete glomeruli, pleural plaques and degenerating fibroids, where dense collagen fuses into glassy bands.
- Hyaline membranes
- Fibrin and plasma proteins lining the alveoli in diffuse alveolar damage (ARDS) and neonatal respiratory distress syndrome.
- Intracellular hyaline
- Protein droplets in kidney tubule cells, immunoglobulin in plasma cells (Russell bodies) and tangled filaments in liver cells (Mallory–Denk bodies).
US spelling: haematoxylin → hematoxylin, fibres → fibers.
Normal function
Arterioles and their walls
Arterioles are the last muscular vessels before the capillaries, and they set how much blood reaches each capillary bed. In the kidney, the brings blood to the and the carries it away.
An arteriole wall has a lining of endothelial cells on a thin basement membrane, then one or two layers of smooth muscle. The endothelium keeps plasma proteins in the lumen, and the smooth muscle contracts or relaxes to match flow to need.
Connective tissue elsewhere is made of collagen fibres in ground substance. In both places, the structure under the microscope is fine and varied; in hyaline change it becomes uniform and glassy.
Underlying change · Step 1 of 5
One look, many materials
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Disrupted function · Step 2 of 5
Hyaline arteriolosclerosis
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Disrupted function · Step 3 of 5
Hyaline in the diabetic glomerulus
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Disrupted function · Step 4 of 5
Hyaline membranes in injured lungs
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Consequences · Step 5 of 5
Hyaline in scars and cells, and its look-alikes
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Symptoms and signs
Symptoms, signs and findings
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Exam detail
Exam detail
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Treatment
How treatment works
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Recap
Recap
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .
Self-check
Check your understanding
The full lesson is part of Student Pro
It takes you through all 5 steps of the mechanism, explains the symptoms, signs and findings each step causes, adds the exam detail and how treatment works where the lesson has them, then recaps it and lets you check yourself with 10 self-check questions. The full pathophysiology library: guided lessons with self-check questions comes with Student Pro, with 100 tutor answers a month and the full available catalogue.
Free to read: the introduction and .