Hypoplasia
Hypoplasia is a term used in medicine for the underdevelopment or incomplete development of an organ or tissue – usually during the embryonic stage – that becomes too small as a result. In practice, hypoplasia comes down to a too small amount of cells present in the organ or tissue concerned. A very rare form of hypoplasia where the cerebellum remains underdeveloped is known as pontocerebellar hypoplasia type 2.
(from Ancient Greek ὑπo- hypo- ‘under’ + πλάσις plasis ‘formation’; adjective form hypoplastic)
Hypoplasia is in fact a mild form of aplasia. Unlike hyperplasia, hypoplasia is a hereditary condition.
Hypoplasia can be present in any tissue or organ. It is descriptive of many medical conditions, including underdevelopment of organs such as:
- Breasts during puberty
- Testes in Klinefelter’s syndrome
- Ovaries in Fanconi anemia, gonadal dysgenesis, trisomy X
- Thymus in DiGeorge syndrome
- Labia majora in popliteal pterygium syndrome
- Corpus callosum, connecting the two sides of the brain, in Agenesis of the corpus callosum
- Cerebellum caused by mutation in the Reelin gene
- Tooth caused by oral pathology, such as Turner’s hypoplasia
- Chambers of the heart in hypoplastic left heart syndrome and hypoplastic right heart syndrome
- Optic nerve in optic nerve hypoplasia
- Sacrum in sacral agenesis
- Facial muscle in asymmetric crying facies
- Thumb from birth
- Lungs, often as a result of oligohydramnios during gestation or the existence of congenital diaphragmatic hernia
- Small bowel in coeliac disease
- Fingers and ears in Harlequin type ichthyosis
- Mandible in congenital hypothyroidism
Pontocerebellar hypoplasia type 2
It is a rare condition that affects the development of the brain.
Pontocerebellar hypoplasia type 2 ( PCH-2 ) is a subtype of the Pontocerebellar Hypoplasia group which contains seven subtypes (PCH1-7). PCH2 an autosomal recessive disease in which the small brains (the cerebellum) are severely underdeveloped. The disease is also known in the Netherlands as the Volendam disease . The disease is characterized by severe problems with movement and cognitive problems.
The brains of patients with PCH-2 are characterized by short cerebellar folia (folds) with little branching (hypoplasia), with the vermis being least affected. In addition, sharply defined areas where the cerebral cortex is missing over the entire thickness, segmental loss of the dentati nuclei with spared islets, segmental loss of the inferior olivarius nucleus , loss of the pontis ventral nuclei with almost completely missing transverse fibers through the pons. In general, it can be said that the cerebellum is much smaller than average. The anterior horn cells of the spinal cord are unaffected.
Symptoms
For most diseases, symptoms will vary from person to person.
Patients have severe intellectual disabilities. Due to the damage to the cerebellum, which controls the execution of movements, patients with PCH-2 have major problems with the control of their muscles. Often they can perform little or no conscious movements, and there are problems with swallowing. They also show all kinds of uncontrolled movements such as dyskinesia or chorea (these are called extrapyramidal symptoms ). There is no cure. Most patients die before age 10.
Hyperplasia
Hyperplasia is the general term in medicine for the enlargement of a particular organ or tissue as a result of abnormally high cell division . Hyperplasia is a response to a specific stimulus and differs from hypertrophy in that the cellular adaptation does not consist in increasing the size of the cells. Only the number of cells increases.
Hyperplasia affects both the parenchyma and the interstitium . Furthermore, it can have both physiological and pathological causes, such as inflammation or endocrine disease . It can also compensate for a deformity or injury elsewhere in the body.
Neoplasia
Neoplasia is a word that new formation means, and that includes both benign and malignant tumors to the extent caused by cell proliferation, and not by edema or hematoma .
In medicine, however, it is often used for cancer , especially in terms that are (too) literal translations of English upright expressions, such as MEN ( multiple endocrine neoplasia , multiple endocrine neoplasia ) and CIN ( cervical intraepithelial neoplasia , cervical intra-epithelial neoplasia ). epithelial neoplasia ). Strictly speaking, CIN is not about cancer, but about a preliminary stage of cancer.
Dysplasia
Dysplasia Ancient Greek : dys = bad [here = mis], puddle sein = shapes, [here = formation]) means, in the human medicine and veterinary medicine a deviation of the mold; it can be a congenital or not hereditary, but also an acquired defect.
Dysplasia in an organ or tissue is an abnormality growth of the tissue structure. Some forms of dysplasia can progress to or indicate an early stage of cancer.
Anaplasia
The Anaplasia means the advancement of higher differentiated cells in less differentiated cells. There is a strongly displaced nuclear-plasma relation, nuclear hyperchromasia and nucleoli enlargement.
Retroplasia
That state of cell or tissue in which activity is decreased below that considered normal; associated with retrogressive changes (for example, injury, degeneration, death, necrosis).
Biological development disorders (cellular, tissue and organic)
This is the progress changes in size, shape, and function during the life of an organism by which its genetic potentials (genotype) are translated into functioning mature systems (phenotype).
- Absence: Agenesis, Aplasia, anaplasia, Aplastia, Atrophy, Atrophic, Atypia
- Deficit (underdevelopment): Dysgenics, Hypoplasia, dysplasia, retroplasia, Displastia, Hypotrophy, Dystrophy, Hypotrophic, dystrophic, Microsoma
- Increase: Hyperplasia, neoplasia, proplasia, prosoplasia, Hypertrophy, pseudohypertrophy, Hypertrophic, Macrosomy, macrosoma
- Transformation: Heteroplasia, metaplasia, desmoplasia, Heteroplastia,
| Feature | Absence | Deficit (underdevelopment) |
Increase | Transformation | Normal |
|---|---|---|---|---|---|
| Primordium (congenital development) In embryology, is an organ or tissue in its earliest recognizable stage of development |
Agenesis
Failure of an organ to develop during embryonic growth and development due to the absence of primordial tissue. |
Dysgenics
The study of things that cause the accumulation and spread of defective and unfavorable genes in the offspring of a population or species |
– | – | (c.f. Eugenics) set of beliefs and practices that aim to improve the genetic quality of a human population |
| Plasia (cell formation) |
Aplasia, anaplasia | Hypoplasia, dysplasia, retroplasia | Hyperplasia, neoplasia, proplasia, prosoplasia | Heteroplasia, metaplasia, desmoplasia | Euplasia |
| Plastia (remodeling) |
Aplastia | Displastia | – | Heteroplastia | – |
| Trophy (growth rates) |
Atrophy | Hypotrophy, Dystrophy | Hypertrophy, pseudohypertrophy | – | Eutrophy |
| Trophic (stimulates growth) |
Atrophic | Hypotrophic, dystrophic | Hypertrophic | – | Eutrophic |
| Typia (quality or peculiarity) |
Atypia | – | – | – | Ortotypia |
| Soma (body living matter) |
– | Microsoma | Macrosomy, macrosoma | – | – |
Sources: PinterPandai, Top Doctors, Radboud University, Washington University in St. Louis