|
|
(20 intermediate revisions by 3 users not shown) |
Line 1: |
Line 1: |
− | {{toplink
| + | |
− | |backcolour = FAFAD2
| + | #REDIRECT[[:Category:Pancreas - Pathology]] |
− | |linkpage =Endocrine System - Pathology
| |
− | |linktext =Endocrine System
| |
− | |maplink = Endocrine System (Content Map) - Pathology
| |
− | |pagetype =Pathology
| |
− | }}
| |
− | <br>
| |
− | ==Anatomy and Physiology==
| |
− | Anatomy and Physiology of the pancreas can be found [[Pancreas - Anatomy & Physiology|here]].
| |
− | ==Degenerative pathology==
| |
− | ===Aetiology===
| |
− | *Hypoplasia of [[Pancreas - Anatomy & Physiology#Endocrine|panceatic islets]] where [[Pancreas - Anatomy & Physiology|exocrine]] cells are functional
| |
− | *Degeneration of the [[Pancreas - Anatomy & Physiology#Endocrine|islet]] cells occurs in [[Pancreas Degenerative - Pathology#Acute pancreatic necrosis|acute pancreatic necrosis]] along with acinar tissue necrosis, atrophy occurs during [[Pancreas Inflammatory - Pathology#Chronic interstitial pancreatitis|chronic interstitial pancreatitis]]
| |
− | *Extensive neoplastic destruction may also contribute to [[Pancreas - Anatomy & Physiology#Endocrine|islet]] loss
| |
− | *Causes [[DM|Diabetes mellitus]] (DM)
| |
− | *In cats
| |
− | **'''Amyloidosis''' of the [[Pancreas - Anatomy & Physiology#Endocrine|islets]] is sometimes observed and may be restricted to just them
| |
− | ***May result in signs of [[DM|DM]] or have no symptoms
| |
− | ***[[General Pathology - Degenerations and Infiltrations#Vacuolar Degeneration|Hydropic (vacuolar) degeneration]] of beta cells
| |
− | ***Acumultion of glycogen within the cytoplasm
| |
− | ***Develops in response to long-term overstimulation due to peripheral insulin resistance
| |
− | *In dogs
| |
− | **'''Sclerosis''' of the islets is sometimes observed in dogs with [[DM|DM]] without pancreatic necrosis but also in dogs without DM
| |
− | <br>
| |
− | '''For degeneration of exocrine tissue''' see [[Pancreas Degenerative - Pathology|'degenerative disease of exocrine pancreas in Alimentary section']]
| |
− | ==Neoplasia==
| |
− | [[Image:Islet cell tumour.jpg|right|thumb|100px|<small><center>Islet cell tumour (Image sourced from Bristol Biomed Image Archive with permission)</center></small>]]
| |
− | ===Insulin secreting neoplasms===
| |
− | [http://w3.vet.cornell.edu/nst/nst.asp Images by Professor J.King]
| |
− | *Adenomas and carcinomas deerived from beta cells
| |
− | *Respond rapidly to iv glucose
| |
− | *Can be identified by immunocytochemical means
| |
− | *Dogs 5-12 years of age most commonly affected
| |
− | *Older cattle, associated with periodic convulsions
| |
− | ====Clinical signs====
| |
− | *Hyperinsulinism
| |
− | *Hypoglycaemia - often episodic
| |
− | **Neurologic signs - stupor, confusion, coma, seizures, peripheral neuropathy may also develop
| |
− | ===Adenomas (insulinomas)===
| |
− | *Usually single, or less often multiple, small (1-3cm) spherical nodule, yellow to dark red, in one or more lobes
| |
− | *Thin layer of fibrous tissue separates normal parenchyma
| |
− | *Small islets of acinar tissue are sometimes present within the neoplasm
| |
− | *Well differentiated cells
| |
− | ===Carcinomas===
| |
− | *Larger than adenomas
| |
− | *Multilobular
| |
− | *Invasive into parenchyma and surrounding tissue
| |
− | *Metastasis into [[Lymph Nodes - Anatomy & Physiology|lymph nodes]], [[Liver - Anatomy & Physiology|liver]] mesentery, omentum
| |
− | *Few mitotic figures
| |
− | ===Gastrinoma===
| |
− | [http://w3.vet.cornell.edu/nst/nst.asp Images by Professor J.King]
| |
− | *Described in dogs, cats
| |
− | *Known as Zollinger-Ellison syndrome in humans
| |
− | *Uncommon compared to beta cell neoplasms
| |
− | *Excess gastrin causes hyperacidity in the stomach and mucosal hyperplasia of the antral region causing gastric and [[Duodenum - Anatomy & Physiology|duodenal]] ulceration
| |
− | ====Clinical signs====
| |
− | *Anorexia
| |
− | *Severe weight loss
| |
− | *[[Control of Feeding - Anatomy & Physiology#The Vomit Reflex|Vomiting]]
| |
− | *[[Diarrhoea]]
| |
− | *Dehydration
| |
− | ====Pathology====
| |
− | *Multiple variably sized neoplasms
| |
− | *Increased connective tissue mass - firm
| |
− | *Partiallty encapsulated
| |
− | *Invade locally
| |
− | *Metastases to [[Liver - Anatomy & Physiology|liver]] and local lymph nodes are common
| |
− | ===Glucagonoma===
| |
− | *Very rare
| |
− | *Characterised by
| |
− | **Hyperglycaemia
| |
− | **Vacuolar hepatopathy
| |
− | **Skin erythema with superficial necrotising dermatitis
| |
− | *Diagnosis in dogs is difficult as presents together with [[DM|DM]]
| |
− | <br>
| |
− | '''For hyperplastic and neoplastic disease of exocrine pancreas''' see [[Pancreas - hyperplastic and neoplastic|'hyperplastic and neoplastic disease of exocrine pancreas in Alimentary section']]
| |