pulmonary MAC, Resp Influenza Flashcards
How do you diagnose NTM lung disease?
(1) Clinical criteria (pulmonary symptoms, nodular or cavitary opacities on cxr, high rest CT showing multifoccal bronchiectasis with multiple small nodules AND exclusion of other diagnoses. (2) microbiologic - positive culture from 2 separate exported samples (or AFB smears/cultures) OR BAL positive culture (3) histo features on biopsy + 1 sputum/bal positive for NTM
what are the 2 radiographic types of pulmonary NTM?
fibrocavitary disease (cavities, fibrosis, plueral involvement) or nodular bronchiectatic disease (multifocal bronchiectasis with small<5mm nodules)
what is the general initial treatment of MAC lung disease?
macrolide (azithromycin/clarifthromycin), rifamycin (rifampin or if hepatoxocitiy, rifabutin), and ethambutol
what is the general treatment for MAC in mild to moderate nodular bronchiectatic disease?
azithromycin (500mg 3x/week), rifampin 600mg 3x/week, and ethambutol (25mg/kg 3x/week)
what is the general treatment for MAC fibrocavitary disease/severe disease
azithromycin (250-500mg) daily, rifampin 600mg daily, ethambutol (15mg/kg daily) + amikacin (10-15mg/kg 3x week for the first 8-16 weeks of therapy provided MIC<64)
how would you treat a macrolide resistant infection based on american guidelines?
ethambutol, rifampin, clofazimine (synergy with amkiacin) with 2-6 months of amikacin 3x/week
what are the British thoracic guidelines for severe MAC treatment?
rifampin, ethambutol, aminoglycoside, + FQ/isoniazid
what do you need to test for prior to initiating therapy in MAC infection?
CBC, CMP, EKG (QT interval), audiogram (macrolide/aminoglycoside), opthomalogy (ethambutol), baseline CT scan
how long do you treat MAC lung infection?
until all sputum cultures negative for at least 12 months. Sputum conversion takes 3-6 months for conversion, so typical treatment time is 15-18 months
what agent can you use if intolerant to rifampin in MAC infection?
clofazimine
when is surgery useful for NTM lung disease?
localized disease (especially upper lobe cavity disease), drugs fail to convert sputum cultures after 6 months of treatment, cannot tolerate medical therapy and macrolide-resistant MAC lung disease
MAC patient has GI intolerance tox? ?
macroline, ethambutol, rifampin products, FQ or clofazimine
MAC patient with abnormal LFTs tox?
macroline, FQ, rifampin products
MAC patient with low WBC tox?
rifampin product
MAC patient with decreased auditory function tox?
amingolycosides/azithromycin
MAC patient with decreased renal function tox?
aminoglycoside
what are the most common MAC species to cause lung disease?
m.avium, M. intracelulae, M. chimaera
what are the 5 typical cxr patterns in a pneumonia?
lobar pattern (strep pneumo, HIb, legionella), bronchopneumonia pattern (staph aureus, gram negatives, mycoplasma, chlamydophilia, viral), interstitial pattern (influenza, CMV, pneumocystis, miliary Tb), lung abscess (anaerobes, S.Aureus), and nodular (right sided endocarditis, histo, coccidio, cryptococcus)
what is considered a poor sputum sample?
More than 10 squamous epithelial cells per lower power field (more from nasopharynx)
what is considered a good sputum sample?
More than 25 PMNs per lower power field (tracheobronchial tree)
what does a predominance of mononuclear cells on sputum gram stain indicate/
mycoplasma, chlamydophilia or a viral infection
what viral influenza disease associated with poultry from china?
H7N9
Illness script associated with H5N1
poultry, 2-8 day incubation, with respiratory failure, bilateral infiltrates, and diarrhea. Clues: Egypt, vietnam, indonesia
how is influenza transmitted?
1-4 day incubation, with shedding 5-7 days after illness onset, with large droplets up to 6 feet.