CF, Non CF bronchiectasis, and atypical infections Flashcards
Two most common filamentous bacteria to pulmonology
Actinomyces and nocardia
Bacteria ubiquitous in soil and is a endogenous in mucus membranes. Causes infection with damaged epithelial barriers.
Nocardia
Aytpical bacteria that favors immunocompetent hosts
Actinomyces
Atypical bacteria that favors immunocompromised hosts
Nocardia
Atypical bacteria that appear like fungal organisms but are thinner and lack septations
Actinomyces and nocardia
Difference in appearance between nocardia and actinomyces on staining
Nocardia more delicate and has right angle branching compared to actinomyces
Staining preferred in nocardia
Romanowsky
Most common species of nocardia in humans
Asteroides
Stain preferred in actinomyces
Papanicolaou
Classic feature of actinomyces slide presentation
macroscopically visible sulfur granule comprised of bacteria and proteinaceous material. IF NOT PRESENT, SUSPECT CONTAMINATION
CD4 count in HIV associated with nocardia
< 100
Finding highly suggestive of actinomyces infection
Bronchocutaneous fistula
Classification of actinomyces and nocardia
acid fast bacilli that are gram negative
NOCARDIA CAN ALSO BE GRAM POSITIVE
Radiographic findings of adenopathy, bronchiectasis, and pleural disease suggest what infection
Actinomyces
Bacteria suggested by rib osteomyelitis and/or empyema or chest wall sinus tract
Actinomyces
Preferred agent in nocardia infection
Sulfonamides, 2 drug regimen until resistance pattern is known
Treatment of nocardia infection in sulfa allergic patient
Minocycline
Treatment of refractory nocardia infection
Zyvox
Duration of treatment for nocardia infection
6-12 months
Drug of choice in actinomyces infection
PCN
Drug of choice in actinomyces infection if PCN allergic
Tetracyclines, erythromcyin, clinda
Clinical presentation of bronchiectasis
cough
sputum production
recurrent respiratory infections
Permanent dilation of the bronchi
3 etiologies of focal bronchiectasis
Mechanical obstruction
Congenital bronchial atresia
Necrotizing pneumonia
Causes of diffuse central bronchiectasis
ABPA
Cartilage syndromes
Inheritance pattern of cystic fibrosis
autosomal recessive with variable penetrance
Gene associated with cystic bronchiectasis
CF gene on the long arm of chromosome 7
Protein malfunction in cystic fibrosis
CF transmembrane regulator protein (CFTR)
Ion channel that regulates liquid volume on epithelial surfaces by secreting chloride and inhibiting sodium absorption
CF transmembrane regulator
Most common CFTR mutation that accounts for 90% of cases of European descent
F508
deletion of single phenylalanine at position 508
Diagnostic criteria for cystic fibrosis
Elevated sweat chloride on 2 occasions OR
ID of mutation known to cause CF on BOTH genes OR
In vivo ion transport abnormalities in nasal epithelium AND
At least one phenotypical feature of CF, sinopulmonary disease, characteristic GI disorders, obstructive azoospermia, salt loss syndrome, OR
Sibling with CF OR
Positive newborn screening
Level of sweat chloride considered normal
< 30
Disease with only 1 CFTR mutation and symptoms of CF
CFTR related disorder
3 most common bacteria in bronchiectasis
H. Influenza
P. Aeruginosa
S. Pneumniae
**S. Aureus atypical
Simplified diagnostic criteria for CF in adult
- Classic symptoms with 1 of the following
- Sweat chloride > 60
- 2 CF mutations
- Sweat chloride 40-60 with strong family history or 1 mutation
Therapy for all CF patients > 6 years old
rhDNase (dornase alpha)
3 drugs that are CFTR modulators for select patients with CF
Ivacaftor
Tezacaftor-ivacaftor
Lumacaftor-ivacaftor
Airway clearance agent in CF indicated for those refractory to dornase alpha or hypertonic saline
Inhaled mannitol
Treatment of CF with antibiotic guidelines
- Don’t cover for staph aureus
- Attempt to eradicate pseudomonas on 1st detection
- Chronic suppression of gram negatives once colonized
Antibiotics used in CF
Inhaled tobramycine or aztreonam
Azithromycin 3x per week
2 drug classes NOT recommended in CF
Leukotriene modifiers Systemic steroids (unless asthma or ABPA)
5 indications for referral for lung transplant regardless of FEV1
- 6MWT < 400 meters
- Hypoxemia at rest or exertion < 88% or Po2 < 55
- Hypercarbia PCO2 > 50
- PA systolic pressure > 50 on echo or evidence of RV dysfunction without tricuspid regurg
- Any exacerbation requiring PPV (CF patients)
Mucolytic agent NOT recommend in Non-CF bronchiectasis
dornase alpha
Only chronic bacteria to be treated with abx in non-CF bronchiectasis
Pseudomonas
Length of time required for symptoms of cough and sputum increase to be considered exacerbation in CF
48 hours
Drug used in the G551-D mutation of CF
Ivacaftor
Drug used in the F508 mutation of CF
Lumacavtor-ivacaftor
Condition with situs inversus, recurrent sinus infections, and pneumonias
Primary ciliary dyskinesia (kartagener’s syndrome)
Genetic abnormality in kartagener’s syndrome
DNAH5 or DNAI1
Diagnostic testing for kartagener’s syndrome
nasal nitric oxide levels
Confirm with microscopy of nasal ciliary brushings
Drug injected into mild tracheal stenosis areas to treat without dilation
Mytomycin C
