Week 9 Chronic Diseases and Infection Flashcards
name some general causes of chronic disease- congenital and acquired?
congenital- genetic, developmental
acquired- vascular, infective, traumatic, autoimmune, metabolic, inflammatory, neurological, neoplastic, degenerative, environmental, idiopathic
what is the pathogenesis of CF?
autosomal recessive
mutation of CFTR gene- defect in cystic fibrosis conductance regulator gene in exocrine glands
range of mutations- most frequent deletion of phenylalanine at position 508
what are the clinical consequences of CF?
defect in CFTR= defect in Cl- transmembrane transport
- mucus becomes dehydrated- viscous and thick causing blockages in small ducts
- lung colonisation and infection with a precession of different organisms
- lung damage, AB and steroid treatment
name some of the infections associated with CF?
H influenzae
Staph aureus
pseudomonas aeruginosa, burkholderia capecia
atypical mycobacteria, candida albicals, asperillus fumigatus
what is the pathogenesis of COPD?
chronic inflammatory responser to inhaled irritant, primarily mediated by neutrophils and macrophage
= chronic bronchitis (small airway disease- obstructive) and emphysema (breakdown of lung tissue- merging of alveoli- less SA)
- also increased mucus production
what microorganisms are associated with acute exacerbations of COPD?
bacterial:
- ps aeruginosa, H influenza, moraxella catarrhalis, , E coli, s pneumoniae
viral:
- respiratory syncytial virus, rhinovirus, parainfluenza virus, human metapneumovirus, coronavirus, adenovirus, influenza A virus
how is DM and its possible complications associated with infection?
hyperglycaemia and acidemia impair- humoral immunity and polymorphonuclear leukocyte and lymphocyte functions
- diabetic micro and macrovascular disease (atherosclerosis)= poor tissue perfusion= increased risk of infection
- diabetic neuropathy= diminished sensation= unnoticed skin
how is DM associated with ENT (ear, nose, throat) infections and what are the common causative micro-organisms?
compromised immune system = malignant or necrotising otitis externa- infection caused by pseudomonas aeruginosa
- infections start in external auditory canal and spread to adjacent soft tissue, cartilage and bone- pts present with severe ear pain and otorrhoea (discharge)
what is rhinocerebral mucormycosis, and how is it associated with DM?
opportunistic infection of sinuses, nasal passages, oral cavity, brain caused by saphrophytic fungi
poorly controlled DM- diabetic ketoacidosis and weakened immune system= infection with mould fungi
- organisms colonise in nose and paranasal sinuses spreading to adjacent tissues by invading blood vessels and causing soft tissue necrosis and bone erosion
how is DM associated with UTIs and what are the usual causative organisms?
neurogenic bladder- dysfunction- overflow incontinence, frequency, urge, retention- due to diabetic neuropathy leads to defects in bladder emptying
- increased risk of asymptomatic bacteriuria and pyuria (puss in urine), cystitis and upper UTIs
- caused by enterobacteriaceae - e.col, psudomonas earoginosa
how is DM and its complications associated with skin and soft tissue infections and what are the usual causative organisms?
hyperglycaemia, sensory neuropathy, atherosclerotic vascular disease all predispose to increased risk of skin or soft tissue infections
- staph aureus (folliculitis, cellulitis)
- group A B-haemolytic streptococcus (cellulitis)
- polymicrobial including staph aureus, B- haemolytic streptococci, enterobacteriaeace and various anaerobes - diabetic foot ulcers and fascilitis
what affect does chronic disease have on structures and how can this relate to infection?
chronic disease alters the structure and function of the affected tissue/organ
- this can potentially alter the interaction between a pt and micro-organism
- may be further affected by the consequences of treatment- Abs and steroids
what infections is downs syndrome associated with and what are the causes of this?
resp infections- bacterial and viral- more common in young
- due to immunodeficiency or other factors- altered mucus secretion or structures of the mouth and airways
- if otherwise healthy will probably not get any more infections than healthy sibling and will respond well to vaccinations
what neurological disorders (CNS and PNS diseases) may affect bladder control?
CNS diseases- alzheimers, cerebral palsy, MS, parkinsons, spinal cord injury, stroke
PNS diseases- nerve damage (neuropathy), neuropathy due to long term alcohol use or DM, vit B12 deficiency
