ID Flashcards
2 places to ignore candida
Sputum and urine
Treatment of Malaria
IV artesunate or IV quinidine
Exchange transfusion in severe cases
Contact + airbone precautions
VZV, ebola, smallpox, covid, MERS-COV
Dx of Blastomyces dermaitidis
Culture or antigen detection
Sx: Anaplasmosis
Intracellular:
Febrile illness
Granulocytes
Filamentous, branching Gram-positive rods
Note the long filaments as well as the beaded, “cocco-bacilli” appearance
- Modified acid-fast stain-positive
- On regular AFB stain, Nocardia is at best weakly positive
Meningititis with petechiae and palpable purpura
N meningititis
Coccidiodomycosis
Spherules with multiple endospores
____ isolation indicated for patients with suspected N meningitides
respiratory
Histoplasmosis
Small pink dots!
Small yeasts with narrow based budding grouped in clusters inside macrophages
Dx of Histoplasma
Culture or antigen detection
Empiric antibiotics for post neurosurgical brain abscesses:
Cefepime + metronidazole (or CNS penetrating carbapenem)
+ vancomycin
Risk factors for mucor (in addition to risk factors for aspergillus and candida)
Iron overload
Diabetes mellitus
Deferoxamine
3 diseases caused by Yernia pestis
Bubonic, septicemic or pneumonic plague
Coccidiodes in soil
Filamentous mycelia
Thin septate hyphae
Gas gangrene/ clostridial myonecrosis
Etiology
Necrotizing infection of muscles with gas formation
Traumatic from penetrating trauma/surgery or spontaneous (hematogenous spread) from GI tract
Tx of Histoplasma
Mild: none or itraconazole
Severe: ampho B then itraconazole
CSF WBC in encephalitis
Typically 5-1000 cells/uL
Endemic fungi + pneuomonia, fibrosing mediastinitis
Histoplasma
Posaconazole covers
Second line agent for most things
Spectrum of Cryptococcus in lung
Where does it spread?
Focal pneumonitis to ARDS
Brain to lead to meningitis
Round encapsulated yeast on India ink
Cryptococcosis
Nocardia
Starts in lungs then disseminates to other organs, most common is brain
Itraconazole AE
Heart failure, QTc prolongation, liver toxicity, pseudohyperaldosteronism, adrenal insufficiency
which endemic fungi has infectious cultures?
Coccidiodes
Alert lab!
Treatment of Invasive Aspergillus
- Voriconazole
Alt:
Posavuconazole if neuro tox or skin issues
Isavuconazole if prolonged QT
Second line agents: echinocandins (caspo, micafungin) or amphotericin B
Aspergillus
Dicotimous branching (equally split)
Septated hyphae that branch at 45 degrees, and is visualized best with periodic acid-Schiff (PAS) or Gomori methenamine silver (GMS) staining
Intra-abdominal abscess treatment duration after drainage if uncomplicated
5 days
Pneumocystis pneumonia
Non-budding cyst
Oval, crescentric, collapsed or helmet shaped
(crushed ping-pong balls)
Giardiasis tx
Metronidazole
Endemic Fungi + broad-based budding yeast
Blastomyces dermaitidis
Tx of CMV esophagitis
Ganciclovir
(large, solitary, shallow ulcers)
Two things that are treated by Echninocandins
- Candida!
- Adjuvent therapy for aspergillus
Deep neck infection
Unasyn
If immunocompromised: cefepime + flagyl
Work-up for patient’s with Nocardia
Brain imaging due to frequency of CNS involvement
Which endemic fungi can act like sarcoid
HIstoplasma
COVID tx
1. no oxygen
2. oxygen
3. NIV/HFNC
- Remdesivir if high risk of progression
- Dexamethasone + Remdes
- Dexamethasone + toci or baricitinib + Remdez if immunoc
No Remdez if eGFR<30
Listeria meningitis is associated with increase rate of ___
Seizure, FND, papilledema
Endemic Fungi
Pneumonia + skin lesions + arthralgias + bone involvement + meningitis
Coccidiodes
Sx of Lyme disease
First stage: fever, erythema migrans (rash)
Second stage: multiple skin lesions, conjunctivitis, arthralgias, myalgias, headache, CN palsies
Third stage: arthritis, encephalopathy, peripheral neuropathy
Tx of coccidiodes
Mild: none
Mod: fluconazole
Severe: ampho-B-> fluconazole
Mucormycosis
Broad, ribbon-like with non-parallel cell walls
Hyphae may brand at obtuse angle
Tx Yersinia pestis
3 options for first line tx
1. Doxycycline
2. Aminoglycoside (streptomycin or gentamicin)
3. Fluoroquinolone (levofloxacin, cipro or moxi)
Monotherapy is fine unless bioterriosim, then use 2 or ask CDC
If pneumonia or plague, don’t use doxycycline (option 2 or 3 instead)
AE of echinocandins
Overall fine
Some drug interactions, LFTs, anaphylaxis, hypoK
What can form sulfur granules as it invades through tissue planes, causing cutaneous fistulas throughout the thoracic cage?
Actinomyces
Treatment of invasive candida
Echninocandins (caspo, mica or anidulafungin)
Droplet precautions
1. precaution
2. which bugs
- Private room preferred, surgical mask within 1 meter of patient, mask during patient transport
Vaxxed: Diphtheria, mumps, rubella, B pertussis
Influenza
H flu, N meningitidis, RSV
No vax: M pneumoniae, pneumonic plague, adenovirus, parvovirus B12, rhinovirus
2 abx with AE of cytopenias
Linezolid (thrombocytopenia)
TMP/SMX
Tx Lyme disease
3 options + one option if can’t take doxy or beta-lactams
Doxycycline, amoxicillin, or cefuroxime
Azithromycin is 2nd line for patients
Voriconazole
AE 4
QTc prolongation
Active hepatitis or severe liver dz
Skin/bone
Visual disturbances
Neurotoxicity
Tx of mucor
Surgical debridement is the mainstay of treatment along with adjuvant antifungal therapy.
Liposomal amphotericin-B is preferred; posaconazole and isavuconazole are second-line or step-down
Blastomycosis
Broad-based budding yeast