ID Flashcards
4 main types of lung/respiratory infections
PNA
Lung abcess
TB
Influenze
Bugs cause
typical CAP
atypical CAP
HCAP
typical CAP = Strep pneumo (#1), H. influenzae (#2), aerobic GNR
atypical: Mycoplasma (#1), Chlamydia, Legionella
HCAP: Staph aureus (#1), Pseudomonas, aerobic GNR
PNA × alcoholics, bug?
klebsiella
PNA + immigrant, bug?
TB
PNA + nursing home, bug?
HCAP (Staph aureus (#1), Pseudomonas, aerobic GNR)
PNA + AIDS, bug?
Pneumocystis carinii (PCP), TB
complications of PNA
pleural effusions, empyema, acute respiratory failure
presentation of typical PNA vs atypical PNA
Typical CAP: sudden-onset fever/chills, productive cough, pleuritic chest pain
Atypical CAP: insidious-onset sore throat, headache, nonproductive cough, dyspnea
Special Dx test when suspect…
TB…
legionella
HIV
suspect TB → acid-fast stain
suspect Legionella → urinary ag
HIV+ → silver stain (fungi, PCP)
When do you admit a person with PNA?
2/5 of CURB-65 – Confusion Uremia, RR ≥30, BP <90/60 age ≥65
outpateint tx of PNA vs inpt tx of PNA
outpatient → Tx azithromycin (<60 y/o), ceftriaxone (≥60 y/o)
inpatient → Tx azithromycin + either ceftriaxone or fluoroquinolone
who gets pneumovax?
> /= 65
aspiration → cough w/ foul-smelling sputum, SOB, fever/chills
how to make Dx?
tx?
lung abcess
Dx CXR (cavitation w/ air-fluid levels, most commonly in right lower lobe)
Tx IV abx
what bugs cause lung abcess?
oral anaerobes (Prevotella, Peptostreptococcus, Fusobacterium, Bacteroides)
1/1 vs 2/2 TB smx
1° TB: granulomatous inflammation in lower lobes → infx contained → usually asx
2° TB: reactivation in upper lobes → fever/chills, night sweats, weight loss, cough w/ hemoptysis
how to dx TB?
Dx
- screen w/ tuberculin skin test (≥15 mm, ≥10 mm if high-risk, ≥5 mm if HIV+ or CXR+)
- confirm w/ CXR (cavitation in upper lobe)
Treatment for active vs latent TB
active TB →
2 mos of RIPES (rifampin, INH, pyrazinamide, ethambutol, streptomyin then
4 mos of INH + rifampin
latent TB → INH only
tamiflu is
oseltamivir
triad of fever, nuchal rigidity, ∆MS
tx? tx?
Dx head CT to check for ↑ICP, then lumbar puncture + CSF analysis
Tx IV abx
Kerning sing vs brudzinski sing
Kerning sign: inability to fully extend knees when lying supine w/ hips flexed
Brudzinski sign: flexion of head causes flexion of hips/knees when lying supine
meningitis, purpura fulminans, bilateral adrenal hemorrhage (W-F syndrome) =
disseminated miningococcal infx
bugs that cause..
Meningitis × neonates:
Meningitis × kids:
Meningitis × adults:
Meningitis × elderly:
Meningitis × neonates: GBS > E. coli > Listeria
Meningitis × kids: MC > Strep pneumo > H. influenzae
Meningitis × adults: Strep pneumo > MC > H. influenzae
Meningitis × elderly: Strep pneumo > MC > Listeria
∆MS, focal neuro sx, s/sx of meningitis
dx?
tx?
encephalitis
*meningitis = triad of fever, nuchal rigidity, ∆MS
Dx head CT to check for ↑ICP, then lumbar puncture + CSF PCR
Tx admit + ACV (for HSV), GCV (for CMV)
bugs that cause encephalitis
- viruses: HSV-1 in temporal lobe, arbovirus, enterovirus
- toxoplasmosis
- aspergillosis
headache, ∆MS, seizures,
nausea/vomiting, focal neuro sx
dx?
tx?
brain abcess
Dx head CT or MRI
Tx IV abx, surgical drainage, ±steroids
bugs that cause brain abcesses
Staph, Strep, anaerobes
Abscess × AIDS: bugs?
Abscess × DKA: bugs?
Abscess × AIDS: toxo, fungi
Abscess × DKA: zygomycosis
Tx for pyelo
uncomplicated → Tx Bactrim or Cipro
complicated → Tx admit + IV amp/gent
fever/chills, dysuria, frequency, urgency, low back pain + boggy, tender prostate
dx? tx?
Dx DRE (boggy tender prostate) + UA/UCx
Tx Bactrim or Cipro
** Chronic prostatitis: usually asx Dx prostatic secretion analysis (↑WBC) and Tx long-term Cipro
usually asx, jaundice, dark-colored urine, RUQ pain, n/v, daycare, travel
bug? ow to dx? tx?
HAV
Dx HAV IgM = acute infx
HAV IgG = previous infx or immunity
Tx supportive care
jaundice, dark-colored urine, RUQ pain, n/v, polyarteritis nodosa, MGN
tx?
HBV
Tx IFN-α
Dx HBsAg = ?
Dx HBsAb = ?
Dx HBeAg = ?
Dx HBcAb IgM = ?
Dx HBsAg = acute/chronic infx
Dx HBsAb = previous infx or immunity
Dx HBeAg = infectivity
Dx HBcAb IgM = window period
jaundice, dark-colored urine, RUQ
Cryoglobulinemia, Chronic infx,
Cirrhosis, Carcinoma, Carriers, IVDA, MPGN
Dx? Tx?
HCV
Dx HCV RNA
Tx IFN-α + ribavarin, liver txp if severe
jaundice, dark-colored urine, RUQ, Deadly, HBV co-infection
dx? tx?
HDV
Dx HDV Ab
Tx IFN-α
jaundice, dark-colored urine, RUQ, cruise ships, fatal in pregnancy
dx?
tx?
HEV
- Dx HEV Ab
- Tx supportive care
viral hep strains that are
- sexually transmitted
- parentally transmitted
- fecal oral route
sex: B and D
parental: B, C, D
fecal-oral: A and E
symmetric, descending flaccid paralysis + canned food or wound infx
C botulism
how to dx and tx botulism
Dx toxin assay
Tx admit + antitoxin
Diarrhea × n/v: viral Diarrhea × fever/blood: Diarrhea × mayonnaise: Diarrhea × raw chicken: Diarrhea × raw seafood: Diarrhea × abx: Diarrhea × travel: Diarrhea × daycare: Diarrhea × AIDS:
Diarrhea × n/v: viral gastroenteritis or food poisoning
Diarrhea × fever/blood: Shigella, Salmonella, Campy, EHEC
Diarrhea × mayonnaise: Staph aureus (
Tx for bacterial gastroenteritis
Tx ciprofloxacin x5 days
C. diff → Tx Flagyl or PO vancomycin
Cellulitis × fight bite:
Eikenella
tx for cellulitis
Tx Keflex or Bactrim, consult ophtho if orbital involvement
“fiery red”, painful skin lesion on face or extremities
Dx? bug? tx?
Erysipelas
Strep pyogenes
Tx w. PCN or erythromycin
bugs that caise nec fasc
strep pyogeneis and C perfringens
tx id debriedment + broad specturm abx
infx of LN → tender LN w/ local cellulitis
bug? dx? tx?
lymphadenitis
skin forlar/strp pyogenes, staph aureus
Tx Keflex or Bactrim, warm compresses
trismus (lockjaw), opisthotonos (spastic back), risus sardonicus (spastic smile)
bug? pathophys? tx?
Tetanus
c. tetani exotoxin = blocks GABA and glycine relase
tx: Tx tetanus antitoxin (TIG) in one site, Td immunization in a different site
OM × IV catheter: OM × prosthetic joint: OM × diabetic foot: OM × nosocomial: OM × IVDA: OM × sickle cell: OM × vertebra: OM × cat/dog bite:
OM × IV catheter: Staph aureus
OM × prosthetic joint: coagneg Staph epidermidis
OM × diabetic foot: polymicrobial
OM × nosocomial: Pseudomonas
OM × IVDA: Pseudomonas
OM × sickle cell: Salmonella
OM × vertebra: TB (Pott dz)
OM × cat/dog bite: Pasturella multocida
how to monitor for resolution of osteomyelitis
serial ESR/CRP
Arthritis × sexually-active young adults:
Arthritis × IVDA:
Arthritis × sickle cell:
Arthritis × sexually-active young adults: N. gonorrhoeae
Arthritis × IVDA: Pseudomonas
Arthritis × sickle cell: Salmonella
erythema chronicum migrans
target shaped lesion in lyme dz
how to dx lyme dz
Dx screen w/ ELISA, confirm w/ WB
Tx doxycycline
triad of HA + fever + rash (vasculitis that starts on extremities and comes inward)
tx?
RMSF
doxy
cyclic fever/chills, headache, anemia, splenomegaly
how to dx? tx?
blood smear w/ giemsa stain
cholorquine (mefloquine if resistent) +/- primaquine for p. vivax/ovale hypnozoites
pain at bite location → fever, malaise →
agitation, photophobia, hydrophobia
(foaming) → paralysis, coma → death
how to dx? tx?
Dx viral cx, Negri bodies on Purkinje cell bx
Tx emergent passive + active immunization
Plasmodium falciparum (24h),
P. vivax and ovale (48h),
P. malariae (72h) via
malaria
vector for malaria
Anopheles mosquito
vector for RMSF
tick
vector for lymes disease
ixodes tick
Rickettsia rickettsii
RMDF
pseudohyphae
candidia
air-crescent sign on CXR
+ hemoptysis
aspergillosis
tx for…
aspergilloma vs invasive aspergillosis
lung lobectomy (aspergilloma)
IV ampho B (invasiveaspergillosis)
need what to get aspergilloma
prior lung caviation
meningitis/encephalitis in HIV+ pts
cryptococcus
vector for crytococcus
via pigeon droppings
vector for histo
bat/bird droppings in caves
how does histo present?
tx?
usually asx, mild respiratory virus
itraconazole
tx for cryptococcis
IV amp B + flucytosine
inflammatory lung dz, granulomatous
nodules in skin and bone
tx?
Blastomycosis
itraconazole
gardener local ulcer + ascending LN-opathy
tx?
Sporotrichosis (“rose gardener disease”)
itraconazole or potassium iodide
usually asx, mild respiratory sx after earthquakes in SW US
tx?
Coccidioidomycosis
itraconazole
- huge spherule w/ endospores
- Broad Based Buds
- macrophage-filled spores
- India ink stain (thick capsules)
- cigar-shaped yeasts
huge spherule w/ endospores = Coccidioidomycosis
Broad Based Buds = Blastomycosis
macrophage-filled spores = Histoplasmosis
India ink stain (thick capsules) = Cryptococcosis
cigar-shaped yeasts = Sporotrichosis
bloating, flatulence, foul-smelling fatty diarrhea?
bug? dx? tx?
Giardia lambii
• Dx stool sample
• Tx metronidazole
flask-shaped ulcers in ascending colon → bloody diarrhea; “anchovy paste” abscess in liver → RUQ pain
bug? dx? tx?
Entamoeba histolytica
- Dx stool sample
- Tx metronidazole (for diarrhea and abscess)
usually asx, can cause bowel obstruction
bug? dx? tx?
Ascaris lumbricoides
• Dx stool sample
• Tx mebendazole
mild diarrhea, severe diarrhea in HIV+ pts
bug? dx? tx?
Cryptosporidium parvum
• Dx acid-fast stain
• (no tx exists
hooks onto bowel walls and sucks blood → iron-deficiency anemia
bug? dx? tx?
Ancylostoma duodenale (old),
Necator americanus (new)
• Dx stool sample
• Tx mebendazole
perianal pruritus, worse at night
bug? dx? tx?
Enterobius vermicularis
scotch tape test
mebendazole
usually asx `→ macrocytic anemia
bug?
Taenia saginata (beef), Taenia solium (pork), Diphyllobothrium latum (fish)
eats vitamin B12 → macrocytic anemia
stool sample
praziquantel
cause fibrosis of liver and spleen
bug? tx?
Schistosomiasis = S. mansoni/japonicum
praziquantel
causes bladder infx → dysuria, bladder SCC
Schistosomiasis = S. haematobium
bugs that cause catheter related sepsis (when left in > __ days)
> 3 days
Staph aureus (#1),
coag-neg Staph epidermidis (#2)
fever/chills, sore throat, malaise, myalgias, severe cervical LN-opathy
dx? tx?
mono
EBV, CMV
monospot test (heterophile agglutination) test
supportive care + avoid contact sports to prevent splenic rupture
