Changes

==Introduction==

==Introduction==

Haemorrhagic diseases can be categorised by two different causal mechanisms:

Haemorrhagic diseases can be categorised by two different causal mechanisms:

*Increased vessel fragility which leads to a non-thrombocytopenic [[Haemorrhage_-_Pathology#Purpura|purpura]].

*Increased vessel fragility which leads to a non-thrombocytopenic [[Haemorrhage#Purpura|purpura]].

*Inadequate haemostatic response. This may be caused by [[Platelet Abnormalities|platelet dysfunction or deficiency]], which leads to a primary or secondary thrombocytopenic purpura, or [[Coagulation Factor Deficiency|deficiencies/derangements of clotting factors]].

*Inadequate haemostatic response. This may be caused by [[Platelet Abnormalities|platelet dysfunction or deficiency]], which leads to a primary or secondary thrombocytopenic purpura, or [[Coagulation Factor Deficiency|deficiencies/derangements of clotting factors]].

Drug-induced and heavy metal damage to the vascular system does occur, although the mechanisms are not clearly understood. Examples include lead, bismuth, mercury, iodides, fluorides, chlorinated hydrocarbon pesticides and salicylates.

Drug-induced and heavy metal damage to the vascular system does occur, although the mechanisms are not clearly understood. Examples include lead, bismuth, mercury, iodides, fluorides, chlorinated hydrocarbon pesticides and salicylates.

Vascular fragility can occur as a consequence of an underlying disease state, which is seen in [[Type III Hypersensitivity|allergy]] or anaphylactic reactions, connective tissue diseases such as Ehlers-Danlos syndrome in dogs, [[DM|diabetes mellitus]] and [[:Category:Antibody Mediated Autoimmune Diseases|antibody-antigen complex reactions]].

Vascular fragility can occur as a consequence of an underlying disease state, which is seen in allergy or [[Type I Hypersensitivity|anaphylactic reactions]], connective tissue diseases such as Ehlers-Danlos syndrome in dogs, [[DM|diabetes mellitus]] and [[Type III Hypersensitivity|antibody-antigen complex reactions]].

==Platelet dysfunction==

==Platelet dysfunction==

==Clotting Factor Abnormalities==

==Clotting Factor Abnormalities==

[[Coagulation Factor Deficiency|Deficiencies]] in clotting factors are often the result of congenital deficiency in one or more of the coagulation factors and can lead to ineffective blood clotting and development of a disease syndrome characterized by excessive bleeding - deficiencies are often detected following trauma or surgery. Occasionally bleeding may be spontaneous (e.g. into alimentary or urinary tracts). Deficiencies are often seen as familial inherited problems; [[Coagulation_Factor_Deficiency#Factor_VIII|Haemophilia (factor VIII deficiency)]] is probably the best understood condition.  

[[Coagulation Factor Deficiency|Deficiencies]] in clotting factors are often the result of congenital deficiency in one or more of the coagulation factors and can lead to ineffective blood clotting and development of a disease syndrome characterized by excessive bleeding - deficiencies are often detected following trauma or surgery. Occasionally bleeding may be spontaneous (e.g. into alimentary or urinary tracts). Deficiencies are often seen as familial inherited problems; [[Coagulation_Factor_Deficiency#Factor_VIII|Haemophilia (factor VIII deficiency)]] is probably the best understood condition.  

[[Category:Haemorrhagic Diseases|A]]

[[Category:Haemorrhagic Diseases|A]]

[[Category:To Do - Blood]]

[[Category:To Do - Blood]]