Long Cases Flashcards
Most common CF infections in younger children
- Staph
- Pseudomonas
- Haemophilus
- E.Coli
- Strep pneumoniae
Most common CF infections in older children/adolescents
- Burkholderia cepacia
- Achromobacter Xylosoxidans
- Stenotrophomonas maltophilia
- Klebsiella
- Enterobacter
- Fungal - aspergillus fumigatus
- Non TB mycobacteria
What is the CFTR protein
Cyclic-AMP regulated chloride channel on the apical surface of epithelial cells - lack of this leads to dehydration of both mucous and airway surface liquid, and disturbance of mucociliary clearance
CFTR modulator drugs
- Lumacaftor and Ivacaftor (Orkambi) used in F508del patients - helps with protein folding
Which CF mutation is associated with pancreatic insufficiency in 99%?
Phe508del (F508del)
Discuss the different CF class mutations
- Class I (3%) - no protein e.g. G542X. Stop mutation, nonsense, short protein which is deleted, therefore no function.
- Class II (90%) - no trafficking e.e F508del. Abnormal folding, trafficking defect, therefore no traffic to cell membrane.
- Class III (5%) - no function. e.g. G551D. Gating defect, protein can get to cell wall but Cl- cannot get out of cell.
- Class IV - less function
- Class V - less protein
- Class VI - less stable
CF monitoring of disease progression
- Infants usually seen weekly
- As get older usually review 3 monthly, and annual review for disease progression with:
- Sputum culture, CXR, nutritional assessment, lung function tests, LFTs, FBC, vitamin levels, total IgE (ABPA)
- Oral glucose tolerance test from age 10yrs or earlier if symptoms or decline in lung function tests
- High res CT scan in primary/secondary school to look for bronchiectasis
Treatment of pseudomonas infection in CF
Ciprofloxacin (but develop rapid resistance) + nebulised antibiotics e.g. tobramycin or colistin (usually alternating month on and off neb antibiotics in chronic pseudomonas to avoid AB resistance). IV = tazocin or ceftazidime
3 significant factors for poor outcome post lung transplant for CF:
repeat transplant, mechanical ventilation at time of transplant, co-existing congenital heart disease
3 main causes of death post lung transplant for CF:
early graft dysfunction, infection, bronchiolitis obliterans
Treatment of DIOS
Nasogastric decompression, IV hydration, enema. If incomplete obstruction then paraffin oil, stool softeners, osmotic laxatives, low residue diet, enema. Can also use NAC, gastrografin.
Predisposing factors for DIOS
Pancreatic insufficiency, under replacement of PERT, meconium ileus, dehydration
Causes of weight loss in CF
Non compliance, insufficient calories, insufficient PERT, CF related diabetes, chest infection, coeliac disease/IBD
Risks of indomethicin treatment
Renal impairment and NEC
Risks of TPN therapy in premature infants
- Extravasation
- Line infections
- Thrombosis
- Conjugated hyperbilirubinaemia (TPN associated liver disease)
Risk of infections in nephrotic syndrome
- Due to loss of immunoglobulins and complement in urine, and steroid treatment
- Especially pneumococcal and streptococcal infections
- Peritonitis and septicaemia
- Treat with oral penicillin prophylaxis while have proteinuria
- Remember immunisations including pneumococcal and influenza
- High dose steroids may mask signs of infection
- Risk of chickenpox and measles
Risk of thrombosis in nephrotic syndrome
- Due to renal loss of antithrombin 3, hyperviscosity, and hypovolaemia
- Can present as macrosopic haematuria (renal vein thrombosis)
- Decreased risk with being well hydrated and mobilsing
High risk groups for subacute bacterial endocarditis?
- Patients with multiple interventions e.g. chronic line placements
- Immunocompromised (immunodeficiency, sickle cell, chemotherapy etc)
- Unrepaired congenital cyanotic heart disease and those with prosthetic materials
- Older patients with CHD
What is appropriate SBE prophylaxis?
Amoxycillin 1hr prior to procedure (1.5g <10y, 3g 10y). If allergic then cephalosporin. May add aminoglycoside if prosthetic heart valve.
How do ACE inhibitors work in cardiac failure?
Reduce afterload (mainly) and preload
What are the important side effects of ACE inhibitors?
Hypotension, renal impairment, hyperkalaemia
When should T21 children have ECHOs?
After diagnosis/birth and again at 6 weeks of age
Down Syndrome adolescents have increased risk of what cardiac diseases?
- 50% develop mitral valve prolapse
- Can also get aortic incompetence
- Hypertension and atheroma risk is low despite obesity and unfavourable lipids
Rates of hearing loss in T21 children and adults?
- 50-80% children
- 90% of adults
- Conductive, sensorineural, or mixed
- Small pinna, narrow canals, impacted ear wax, middle-ear fluid