growth disorders

Question 1

what are 3 developmental disorders due to too little growth?

Answer 1

agenesis, aplasia, hypoplasia

Question 2

what is agenesis?

Answer 2

organ doesn’t develop at all, foetus usually doesn’t survive, eg no salivary glands

Question 3

what is aplasia?

Answer 3

an organ fails to develop normal structure from primitive embryonic development

Question 4

what is hypoplasia?

Answer 4

less tissue formed, but normal structure, eg enamel

Question 5

what is a developmental disorder based on too much growth?

Answer 5

hamartoma- tumour like
only in patients growth period, but excessive
not benign
eg. moles, haemangioma, lymphangioma

Question 6

what is a haemangioma?

Answer 6

b.v
present at birth
or
vascular malformation- appears later in life, common

Question 7

what is a lymphangioma?

Answer 7

mostly cavernous, tongue, cystic hygroma

Question 8

what is a developmental disorder in the wrong place?

Answer 8

ectopia-normal tissue abnormal site
eg mickel’s diverticulum-s.i pouch
ectopic tooth

Question 9

what is an acquired growth disorder?

Answer 9

adaptation of cells to environmental stresses

Question 10

what is atrophy?

Answer 10

reduction in size and number of cells
physiological- hormonal influence
pathological

Question 11

give examples of localised atrophy?

Answer 11

ischaemic, pressure, disuse/denervation, autoimmune, idiopathic

Question 12

give examples of generalised atrophy

Answer 12

nutritional, senile, endocrine

Question 13

describe osteoporosis

Answer 13

related to exercise, ageing, hormones- oestrogen has inhibitory effect on osteoclasts

Question 14

what is hyperplasia?

Answer 14

increase in cell numbers
can result in response to stimulus and regression
cells must be capable of division

Question 15

what are 2 causes of pathologic hyperplasia?

Answer 15

endocrine

chronic injury and inflammation

Question 16

what are 3 mechanisms of hyperplasia?

Answer 16

GF driven proliferation of cells
increased output of cells from stem cells
liver regeneration

Question 17

what is hypertrophy?

Answer 17

increase in cell size due to increased production of cellular proteins
often occurs with hyperplasia

Question 18

what is goitre?

Answer 18

result of dietary iodine deficiency
decreased synthesis of thyroid hormone
compensatory increase in TSH
thyroid follicular cell hypertrophy and hyperplasia together

Question 19

what is metaplasia?

Answer 19

change from one differentiated form of a tissue to another
adaptive response
results from changes in environmental demand
reprogramming of stem cells or undifferentiated mesenchymal cells

Question 20

give 2 examples of metaplasia/

Answer 20

in smokers: ciliated columnar epithelium to squamous metaplasia
barrett’s oesophagus: squamous to columnar

Question 21

what is dysplasia?

Answer 21

disordered growth
can occur in metaplastic tissue
mostly seen in epithelia
severity may indicate that there is the potential for malignant change

Question 22

what is neoplasia?

Answer 22

abnormal mass of tissue
excessive growth
uncoordinated with normal tissue
persists after provoking stimulus is removed
includes benign and malignant tumours