Module 5 Part 2 - Chronic and System Disease Flashcards
Systemic Lupus Erythematosus (SLE)
Auto immune disease Acute or insidious onset Chronic often febrile (fever) illness characterised by injury to the skin, joints, kidney and serosal membranes More common in females Example of symptoms: - discoid skin rash - oral ulceration - skin photosensitivity - serosal inflammation - arthritis - haematological disorder
Immunological Diagnosis of Suspected SLE
There is a cluster of antibodies that are aimed against the nuclei (antinuclear antibodies - ANAs) that can be used for diagnosis
These are not specific for SLE and can occur in some of the lupus-overlap syndromes with other connective tissue diseases
Anti-dsDNA (antibody against dsDNA) - is the most frequently detected and specific autoantibody
Anti-ssDNA (antibody against ssDNA) - may be found in SLE, but is also found in other diseases
Anti-DNA histone - found commonly in drug-induced SLE
Musculoskeletal Symptoms of SLE
Arthritis - fingers, wrists and knees, evidence of avascular bone necrosis
Bone disease - severe osteoporosis (might be related to corticosteroid therapy)
Myalgia - pain in the skeletal muscles associated with a lymphocytic vasculitis
Diabetes Mellitus
It is a multisystem disease with both biochemical and structural consequences
It is a chronic disease of carbohydrate, fat and protein metabolism, resulting from inadequate action of the hormone insulin
Common underlying feature is hyperglycemia
Differences between Type 1 and Type 2 Diabetes Mellitus
Type 1 - childhood and adolescence onset - thin people - ketoacidosis common - severe insulin deficiency - islet-cell antibodies - autoimmune mechanism - genetic predisposition associated with HLA-DR genotype Type 2 - late to middle age onset - obese - ketoacidosis rare - relative deficiency and end-organ resistance - no islet-cell antibodies - no autoimmune mechanism - polygenic inheritance
Pathology of Hyperglycemia (HGC)
Increasing insulin resistance i.e. loss of cell surface receptors for insulin results in HGC
HGC leads to glycosylation of proteins, LDL-AGE’s (advances glycosylation end products)
Results in increased cell damage e.g. microvasculature
Major Complications of Diabetes
Predisposition to infection
Increased severity of atherosclerosis and its complications
Extensive small vessel disease (arteriolosclerosis)
Renal glomerular diseases
Retinal vascular damage
Peripheral nerve damage
Gall Bladder
Muscular sac lined with simple columnar epithelium
Stores 50-100 ml of bile from the liver via the hepatic and cystic duct
Attached to the Glisson’s capsule of the liver
Lumen is covered by the mucosa (simple columnar epithelium overlying the lamina propria)
Epithelial cells have microvilli, and look like absorptive cells in the intestine
Wall of the bladder doesn’t have a muscularis mucosa or submucosa
Muscularis externa contains bundles of smooth muscle cells, collagen and elastic fibres
In the adventitia, thick layer of connective tissue with blood vessels, nerves and lymphatic network
How does the Gall Bladder Work?
The gall bladder is stimulated to contract and expel bile into the duodenum by the hormone cholecystokinin pancreozymin (CCK)
CCK is produced by the enteroendocrine cells of the duodenal mucosa
The production of this enzyme is stimulated by the presence of fat in the proximal duodenum
The contractions expel bile into the common bile duct, and the bile is then carried to the duodenum
Cholelithiasis (Gallstones)
Affect 10-20% of adult population in developed countries
Vast majority of gallstones are silent and most individuals remain free of biliary pain or stone complications for decades
Two main types:
1. Cholesterol stones
- about 80%
- contains more than 50% of crystalline cholesterol monohydrate
2. Pigment stones
- composed mainly of bilirubin calcium salts
Pathological Effects of Gallstones
Cholestasis and abscess formation in the liver
Carcinoma
Pancreatitis
Inflammation of path due to blockage
Examples of Chronic Liver Disease
Common - alcoholic liver disease - cryptogenic - chronic hepatitis Uncommon - autoimmune chronic hepatitis - chronic biliary obstruction - cystic fibrosis Treatable but rare - hemochromatosis - Wilson's disease
