Infectious Disease Flashcards
First Aid and NEJM Knowledge +
Location of abnormal signal for meningitis 2/2
(a) HSV-1
(b) Tb
(a) Temporal lobes
(b) Basilar
Causes of persistent CSF pleocytosis:
lymphocytic vs. neutrophilic
Chronic meningitis most likely to be lymphocytic: weeks duration of elevated CSF white count
Lymphocytic- 40% Tb, atypical mycobacteria, cryptococcus 7% (HIV+ pts get cryptococcus meningitis), coccidio, histo, blasto
Neutrophilic- less common- nocardia, actinomyces, aspergillus, candida, SLE
Causes of persistent CSF eosinophilic pleocytosis
Coccidio, parasites, lymphoma, chemical agents
Mollaret’s syndrome
Recurrent HSV-2 meningitis
Bugs responsible for aseptic meningitis
fall vs. spring
Aseptic meningitis- typically viral w/ benign course
Late summer/early fall: enteroviruses (coxsackie) and arboviruses (arthropod-borne = eastern/western equine, St Louis)
Spring: mumps
What drugs typically can cause medication-induced aseptic meningitis
TMP-SMX, IVIG, NSAIDs, carbamazepine
Most common bugs that cause bacterial meningitis
(a) 18-50 yoa
(b) Over 50 yoa
(c) HIV
(d) Post-neurosurgical
Bacterial meningitis
(a) Typical adults: Strep pneumo and neisseria meningitis
(b) Over 50: S. pneumo, listeria monocytogenes, GN bacilli
(c) HIV: S. pneumo, listeria, GN bacilli (pseudomonas)
(d) Post-neurosurgical: S. pneumo then staph aureus, also GN bacilli
Empiric abx for bacterial meningitis in
(a) Typical adult
(b) Adult over 50
(c) HIV
(d) Post neurosurgical
(a) CTX, vanc
(b) CTX, vanc, ampicillin
(c) Ceftazidime (pseudomonal coverage), Vanc, Ampicillin
(d) Ceftazidime and Vanc
When to use steroids during empiric tx of meningitis
IV Dex 10mg q6h for 2-4 days when bacterial meningitis suspected due to Strep pneumo
CSF findings of traumatic tap
Expect some more cells
Correction factor: expect 800 RBCs per 1 WBC, expect 1mg protein per 1000 RBCs
Causes of CSF studies with
(a) Low glucose
(b) PMNs vs. lymphocytes
CSF studies
a) Low glucose: bacterial, fungal (Tb
(b) PMNs = bacterial
lymphocytic = fungal, viral
Who gets meningitis prophylaxis?
Rifampin for roommates, cellmates, close to respiratory secretions (ET tube, kissing, sharing utensils) within the last 7 days for suspected neisseria meningitis
CSF of bacterial vs. fungal meningitis
Bacterial- neutrophils
Fungal- lymphocytes
Then both w/ low glucose, high protein, high opening pressure (above 20)
List causes of chronic meningitis + cranial nerve palsy
- Lyme disease
- Syphilis
- Sarcoid (CN VII = Bell’s)
- Tb (CN VI)
Encephalitis plus causes
(a) plus flaccid paralysis
(b) plus rash
Encephalitis (headache, fever, nucchal rigidity PLUS focal neurologic sign)
(a) encephalitis preceded by flaccid paralysis in West Nile virus b/c it infects the anterior horn cells
(b) See a rash in VZV encephalitis (zoster rash), Lyme (targetoid), RMSF
Most common causes of encephalitis in the US
(a) Whichcarries the highest mortality
HSV and arboviruses (arthropod aka mosquito-borne): West Nile
(a) HSV encephalitis- mortality of 70%
Typical causes of encephalitis in
(a) Summer
(b) Fall
(c) Winter
Encephalitis bugs
(a) Summer- think tick-borne = Lyme, RMSF, Ehrlichiosis
(b) Fall- think mosquito/arthropod borne (arboviruses) = West Nile, east equine, west equine, St. Louis virus
(c) Winter- measles, mumps
Compare bugs that cause infective endocarditis of
(a) native valve
(b) prosthetic valve
(c) valve in IVDU
Infective endocarditis
(a) Native valve- Strep viridans, other strep. Then S. aureus and enterococcus
(b) Prosthetic valve- Staph epi, Staph aureus
(c) Staph aureus
Bacteremia of which 2 bugs should spark workup for GI pathology (search for colon CA)
Strep bovis
Clostridium septicum
What is marantic endocarditis
Nonbacterial thrombotic endocarditis = Marantic endocarditis = Libman-Sacks endocarditis
- noninfectious endocarditis due to deposition of thrombi on heart valves
- seen mostly in cancer and SLE
Libman-Sacks endocarditis
Libman-Sacks endocarditis = specific kind of noninfectious endocarditis seen in SLE due to autoantibodies against heart valves
Duke’s criteria
For diagnosing infective carditis: 2 major, 1 major w/ 3 minor, or 5 minor
Major criteria:
- new regurg murmur
- new oscillating vegetation on TTE
- BCx w/ typical organism
Minor criteria:
- Fever
- Predisposing condition: prosthetic valve, IVDU, valvular heart disease
- BCx w/ atypical organism
- Embolic phenomenon: Janeway lesion, pulm or intracranial infarcts, conjunctival hemorrhage
- Immunologic phenomenon: Osler nodes, glomerulonephritis, Roth spots
Indications for surgery in endocarditis
- Vegetation causing conduction abnormality: AV dissociation, new LBBB, PR prolongation (suggestive of abscess)
- Intractable HFrEF
- Fungal
- Recurrence of fever after 5 days of abx
- Persistent bacteremia
- Most cases of prosthetic valve
Empiric abx tx of
(a) native valve endocarditis
(b) prosthetic valve endocarditis
(a) Native valve endocarditis: cover strep viridans, other strep, then staph and enterococcus: vanc!
(then narrow to nafcillin)
(b) Prosthetic valve endocarditis: Staph epi, staph aureus: vanc, gent (used for synergy against enterococci), and cefepime (pseudomonal coverage)
EEG findings of
(a) Encephalitis
(b) Specifically HSV encephalitis
(a) Diffuse slowing of brain waves
(b) Characteristic slow wave (2-3 Hz) complexes classically localizing to temporal lobes
Name the HACEK organisms
Haemophilus Actinobacillus Cardiobacterium Eikenella Kingella
Non-bacterial causes of infective endocarditis in IVDU
Aspergillus, candida
Which populations require abx ppx for dental procedures?
Prosthetic heart valve
H/o infective endocarditis
For ppl w/ history of infective endocarditis, for which procedures are prophylactic abx recommended?
Prosthetic heart valve or history of endocarditis: get ppx abx x1 for dental procedures, infected MSK or skin stuff (abscess I&D), incision into respiratory mucosa (tonsillectomy, transbronchial biopsy)
Potential UA findings in infective endocarditis
Immunologic sequelae = Osler nodes, kidney deposits causing glomerulonephritis
UA with microscopic hematuria and RBC casts
Definition of FUO
Fever of unknown origin: T of at or over 100.9F for 3 or more weeks
-so it’s the fever cuttoff and the duration (3 weeks)
w/ etiology not diagnosed after a certain amount of outpatient visits/hospitalizations
3 buckets for etiology of FUO
- Infectious- Tb, endocarditis, abscess
- Neoplastic- Leukemia, lymphoma
- Autoimmune- Adult Still’s disease, cryoglobulinemia, SLE, polyarteritis nodosa
Mononucleosis
(a) Name 3 indications for steroids in acute mono
(b) Serum test
(c) Characteristic lab finding
Mononucleosis
(a) Tonsillar obstruction of airway, thrombocytopenia, autoimmune hemolytic anemia
(b) Heterophile antibody
(c) Peripheral smear- atypical lymphocytes (reactive T-lymphocytes w/ large eccentric nuclei) seen in 70% of cases
Etiology of osteomyelitis
(a) sternoclavicular joint of an IVDU
(b) HIV pt
(c) Sickle cell disease
(d) Human bite
(e) prosthetic joint
Bug causing osteo- overall most common is staph aureus
(a) in sternoclavicular joint of IVDU- pseudomonas for some reason
(b) HIV pt- Tb, Bartonella
(c) SCD- salmonella
(d) Human bite- eikenella
(e) Prosthetic joint or post-op infection: coagulase negative staph = staph epi and staph saprophyticus
Key ways to distinguish cystitis and pyelo
Fever and WBC casts present in pyelo
Lab descriptors to differentiate staph species
Gram positive cocci
Catalase positive = staph (vs catalase negative strep)
- GPCs, catalase positive, coagulase positive = Staph aureus (errrrything positive)
- GPCs, catalase positive, coagulase negative (‘coag-negative staph’) = staph epi, staph saprophyticus
Plain film findings of osteomyelitis
Osteo on Xray: can initially be normal then developing about 2 weeks after infection: bony erosions or periosteal elevation
What kind of UTI is proteus known for?
Proteus = urase-producing (so is pseudomonas) so it causes struvite stone obstruction causing pyelo
Management of intrarenal abscess vs. perinephric abscess
Intrarenal abscesses comes from infection of a renal cyst- typically are small (below 5cm) and can be management w/ abx alone
while perinephric abscesses require perc or surgical drainage
Lab descriptors to differentiate strep species
Gram positive cocci
Catalase negative = strep (vs. catalase positive staph)
- Beta-hemolytic = GAS (strep pyogenes) and GBS (Strep agalactiae)
- Alpha-hemolytic = Strep pneumo (optochin pos) and Strep viridians (optochin neg)
- Non-hemolytic, catalase negative GPCs = E. fecalis, E fecium
24 y/oF returned 2 weeks ago from Thailand, now has fever and night sweats x4 days. No GI complaints, rashes, freshwater exposure
Most likely diagnosis
(a) Malaria! Most dangerous species is plasmodium falciparum- most likely here b/c of rapid onset (about 1 week after travel, while other plasmodium species have dormant liver stages
- Ddx given fast onset also includes dengue but would expect prominent myalgias/arthralgias
Malaria
(a) Lab results that support the diagnosis
(b) Lab test to confirm
(a) Low H/H b/c of RBC lysis
(b) Thick and thin smear showing P falciparum “banana shaped gametocytes” inside RBCs
Malaria treatment
Malaria tx depends on species
- P. malariae: chloroquine only
- P. vivax and P. Ovale are “very old”: have dormant liver stage (hypnozoites) that can present months of years after exposure: tx with chloroquine then also primaquine to eradicate chronic liver stage
-Plasmodium falciparum is the most dangerous- assume chloroquine resistance and tx w/ quinine plus doxy (or atovaquone/proguanil)
Places that travelers should get malaria ppx for travel to
SE Asia (Thai-Cambodia), sub-Saharan Africa
Central America, Haiti, parts of Middle East
Primaquine
(a) Main use
(b) Main contraindication
(a) Antimalarial
Primaquine- add to chloroquine for eradication of dormant liver stage of Plasmodium vivax and ovale
(b) G6PD deficiency- b/c can lead to severe hemolytic anemia
Primaquine
(a) Main use
(b) Main contraindication
(a) Antimalarial
Primaquine- add to chloroquine for eradication of dormant liver stage of Plasmodium vivax and ovale
(b) G6PD deficiency- b/c can lead to severe hemolytic anemia
Drug ppx for malaria
Chloroquine for central America, Haiti, parts of Middle East
SE Asia (Thai/Cambodia border): doxy or atorvaquone/proguanil b/c resistance is common
Mefloquine or atovaquone/proguanil for everywhere else
Why bactrim alone is sufficient for an abscess post I&D but isn’t sufficient for cellulitis
Abscess- really staph
But when cellulitic (surrounding erythema): need to also cover for strep pyogenes => need a beta-lactam (PCN or cephalosporin) => add keflex
Illness script for pertussis
(a) Treatment
Pertussis: severe and persistent paroxysmal coughing episodes after initial fever and nasal congestion
-can be prolonged cough in vaccinated
(a) Azithro
2 MC pathogens causing post-influenzal PNA
Strep pneumo and staph aureus
Centor criteria
For diagnosing strep throat
4 things: 3 or more means should test
- fever
- tender cervical lymphadenopathy
- tonsillar exudate
- absence of cough
34 y/o w/
atypical PNA
targetoid lesion rash
mild hemolytic anemia
(a) Dx
(b) Tx
(a) Mycoplasma PNA
causes IgM cold agglutinin hemolytic anemia
Targetoid lesion rash- erythema migrans that can even involve hands and feet
(b) Tx w/ azithro
49 y/o w/ chlamydial urethritis
Tx
Tx for nongonococcal urethritis = azithro (1g PO x1)
While if have gonorrohea: that’s when treat for co-existing: so if have gonorrhea give CTX x1 and azithro x1
What degree of induration is considered positive for a TST?
Tuberculin skin test
5mm or more in immunocompromised (HIV) or recently exposed
10mm or more if recently (within 5 yrs) immigrated from Tb endemic area
15mm or more positive for everyone else
Ways to reduce risk of C. Diff recurrence
No antacids
Take probiotics if need another course of non-C. Diff abx
Tx regimens for first recurrence of C. Diff
If treated w/ flagyl- give PO vanc
If first one treated w/ vanc- give prolonged and tapered course of pulsed PO vanc or fidoxomicin
Presentation of strongyloides
(a) Normal
(b) Immunocompromised
Strongyloides = parasitic worm
(a) In immunocompetent: vague epigastric pain, nausea, bloating, diarrhea (vague GI complaints)
(b) HIV, chronic steroids, organ transplant: hyperinfection (autoinfection) = dissemination
worms leave GI tract and invade lungs (=> cough/hemoptysis) etc
Places where strongyloides is endemic
Warm climates
SE US
Africa, Asia
Carribean
Central America
Explain mechanisms of complications of strongyloides
(a) SBO/ileus
(b) bacteremia/meningitis
(c) hemoptysis
Strongyloides = parasitic worm
(a) Can reproduce in the small intestines => high worm burden which can lead to SBO/ileus
(b) Tracking of enteric bacteria (gram negative rods, enterococci) => bacteremia/meningitis
(c) Disseminated/hyperinfection (in immunocompromised): worms leave GI tract to lungs
How to diagnose strongyloides?
(a) Who to expect eosinophilia in?
Strongyloides = parasitic worm that reproduces in small intestines and can spread to lungs
Diagnose with stool O&P
Serology if needed
(a) See eosinophilia in immunocompetent (not in the immunocompromised who get the hyperinfection)
Tx for strongyloides
Strongyloides = parasitic worm that replicates in small intestines and can spread to lungs
Treat with anti-helmiths = thiabendazole, albendazole, ivermectin
Lab tests for evaluation of traveler w/ eosinophilia
- Thick and thin blood smear for malaria
- BCx for typhoid fever (salmonella typhi) and meningococcus
- Stool culture and O&P
Entameoba histolytica
(a) Clinical presentation
(b) Dx
(c) Tx
Entameoba histolytica = amebiasis
(a) Presents w/ bloody diarrhea
(b) Diagnose w/ stool microscopy
(c) Tx flagyl then paromomycin to eradicate stool cysts
- Don’t need to drain liver abscess!!!
Management of amebiasis w/ liver abscess
Don’t need to drain! good enough to treat entameoba histolytica with flagyl then paromomycin to eradicate stool cysts
Illness script for Dengue fever
Dengue fever = “break-bone” fever: acute onset (5-7 days within travel) fever, myalgias, arthralgias, retroorbital ehadache followed by several weeks of fatigue
Illness script for Typhoid fever
Typhoid fever = enteric fever
step wise onset of high fever (over 3 weeks) and fatigue, vague abd pain
typical rose spot rash
Typhoid fever
(a) How to diagnose
(b) Tx
Typhoid fever
(a) Diagnose with blood cultures growing salmonella typhi, but often empirically treated
- high suspicion in traveler returning 5-21 days ago w/ fever for more than 3 days and GI symptoms
(b) Floroquinolones- Cipro, levofloxacin
Feared complication of typhoid fever
Intestinal perf => secondary bacteremia => overwhelming bacteremia causing death
Swimmer’s Itch
Swimmer’s itch = itchy/pruritic rash at site of acute schistosomiasis infection where fluke entered the body
hypersensitivity rxn to blood fluke at site of entry
itchy rash after swimming in fresh water
What is Katayama fever?
Katayama fever = acute schistosomiasis syndrome
immunologic rxn to the organism occurring 4-8 weeks after exposure
fever, myalgias, dry cough, diarrhea, diffuse lymphadenopathy and HSM
Infectious diseases to consider for fever after
a) Travel within 21 days
(b) Longer incubation periods (fever onset after 21 days from travel
Fever in traveler
(a) Short incubation period: typhoid fever, plasmodium falciparum (worst species of malaria), dengue fever
Leptospirosis, rickettsial illness, meningococcemia
(b) Longer incubation period: non-falciparum malaria, Tb, hepatitis, amebic liver abscess, acute HIV, brucellosis
Tx of
(a) Dengue fever
(b) Typhoid fever
Tx of
(a) Dengue fever- acute onset fever few days after travel with myalgias/arthralgias and headache (break-bone fever)
supportive tx
(b) Typhoid fever due to salmonella typhi => treat with floroquinolones (cipro, levaquin)
Asplenic pateints
(a) What vaccines do they need?
(b) When to give these vaccines
Asplenia- at risk for infection w/ encapsulated organisms = S. pneumo, N. meningitis, H. influenza B
(a) S. pneumo, meningitis, and HIB vaccines
(b) Either 2 weeks before elective splenectomy or 2 weeks after procedure
Who gets abx ppx post-splenectomy?
(a) With what?
Children post-splenectomy get ppx PCN or amoxicilin until age 5 or for at least one year post-splenectomy
When does acute HIV present?
(a) When do Ab turn positive?
Acute HIV presents 2-6 weeks after exposure
(a) Takes 1-3 months (really 3 months to be sure) for Ab to be positive
2 approved tests for diagnosis of acute HIV
Diagnosing acute HIV (before 3 months where antibodies aren’t reliably positive)
- HIV viral load
- p24 antigen
Name all ppx drugs someone with HIV and CD4 under 50 should be on
HIV pt ppx:
bactrim under 200 for PCP ppx, also bactrim when under 100 and +toxo IgG for toxoplasma encephalitis ppx (but should already be on it)
then add azithro when under 50 for MAC ppx
Describe the three drug regimen for HAART
3 drug regimen: 2 nucleoside analogs (AZT, abacavir, tenofovir, emtricitabine) then plus one of the following
- non-nucleoside analog: nevirapine, efavirenz
- protease inhibitor = fosamprenavir
- integrase inhibitor = raltegravir
Clinical manifestations of MAC
(a) Expected CT findings of disseminated MAC
MAC: fevers, weight loss, lymphadenopathy
can have diarrhea/abd pain, splenomegaly
(a) See mesenteric lymph node enlargement
First line antimicrobial regimen for MAC infection in HIV+ pt
MAC tx: macrolide (clarithromycin or azithro) plus ethambutol
then also plus rifambutin if failing ART
Diagnostic tests for MAC infection
Diagnosing MAC- need to get biopsy, typically negative in blood in non-disseminated infection, get lymph node biopsy or BAL wash
HIV+ pt with CD4 count 82 p/w fever, headache, AMS
(a) Suspected diagnosis
(b) What further testing?
(a) Toxoplasma gondii encephalitis
(b) LP and send for toxo antibodies
Then also NCHCT for multiple ring-enhancing lesions
Imaging findings of toxoplasma gondii encephalitis
Multiple ring enhancing lesions
2 clinical presentations of cryptococcus neoformans in HIV+ pts
Cryptococcus neoformans =>
- meningitis: often subacute
- pneumonia
First line treatment regimen for cryptococcus meningitis
Cryptococcus neoformans tx:
induction w/ amphotericin B and flucytosine
consolidation w/ fluconazole
maintenance w/ fluconazole
HIV+ with CD count 60 w/ persistent watery diarrhea
First line diagnosis?
Persist watery diarrhea in immunocompromised (typically CD4 under 100) = cryptosporidiosis
3 main clinical syndromes that CMV causes in HIV+ pts
- Retinitis
- Esophagitis
- Colitis
Tx of CMV
(a) Side effects of tx
Ganciclovir
(a) Risk of bone marrow suppression
MC bugs causing catheter-related infections
(a) Empiric tx
Catheter related infections: MC is coag negative staph (staph epi), then staph aureus, enterococcus, candida
(a) Empiric tx w/ vanc
Complications of catheter-related infections
Complications:
septic thrombophlebitis
septic emboli (ex: pulmonary)
infective endocarditis
Do you have to remove all devices when there is concern for device related infection?
No- if uncomplicated infection of tunneled catheter or implantable device can first try to get away with just abx
Unless there’s candidemia- then need to remove
What do we use to test for C. Diff?
Don’t test the stool for the bacteria itself, but for the toxin it produces
82 y/oF on CTX for UTI who develops diarrhea
Why likely not C. Diff?
C. diff diarrhea typically develops about 1 week after abx exposure
Distinguish airborne from droplet precautions
Airborne = negative-pressure room with N-95 respirators for staff
protects against droplet (tiny) nuclei
Tb, measles, SARS, vesicular rashes (VZV, chicken pox)
vs.
Droplet = private room, facemask for staph
protects against large particles that can suspend in air for 3 feet
Meningococcus and H. influenza meningitis, influenza, pertussis
What diseases warrant the following
(a) airborne precautions
(b) droplet precautions
(c) contact precautions
Everyone gets standard- duh wash your hands, wear PPE for splashes duh
(a) Airborne (negative pressure room and N-95 respirators) for Tb, VSV, chicken pox, measles, SARS
(b) Droplet (private room, wear mask) for meningococcal/H. influenza meningitis, influenza, pertussis
(c) Contact precautions (wear gown and gloves always) for C. Diff, vesicular rash (VSV, chicken pox), SARS
Describe shape of staph vs. strep
Staph like grapes come in clusters
‘Gram positive cocci in clusters’ = staph
Strep- in chains and pairs
Buzzwords
(a) lancet-shaped pairs
(b) coagulase negative GPC
(c) GPCs
(a) lancet-shaped pairs of GPCs = strep pneumo (ex: as seen in pneumococcal pneumonia sputum Cx)
(b) coag negative staph = staph epidermidis and staph saprophyticus
(c) gram positive cocci = staph and strep
How to differentiate the two gram positive branching rods
Abnormal gram positive bacteria shaped in branching rods = actinomyces and nocardia
Nocardia- partially/weakly AFB positive, can grow under aerobic conditions (neither of which actinomyces are)
Lumpy jaw or draining fistula with sulfur granules on pathology
Actinomyces- gram positive bracing rod that presents as draining fistula/sinus in the mandible, lung, or abdomen/pelvis
How does nocardia present clinically?
Immunocompromised (HIV, chronic steroids, leukemia) pt w/ lung, CNS, or ski abscesses
Two clinical presentations of bartonella
- cat-scratch disease = fever, regional lymphadenopathy around catch bite
- bacillary angiomatosis = FUO in AIDS pt w/ purple lesions
Bacillary angiomatosis clinical presentation
AIDS pt w/ purple skin lesions that resemble (but are not…) Caposis sarcoma
Fever- cause of FUO in AIDS pt
Blood filled cystic lesions in liver and spleen
Tx for cat-scratch disease
Cat-scratch disease = fever, regional lymphadenopathy around cat bite 2/2 bartonella hensilae
Tx = macrocodes (azithro)
Next step for any pt with
(a) Candidemia
(b) Candiduria
(a) Any candida in blood: need optho exam to r/o candida endopthalmitis
(b) Candida in urine can be a frequent colonizer => look for WBCs and symptoms
No oral antifungals needed if asymptomatic
Clinical hint to candida vs. CMV esophagitis
CMV esophagitis typically CD4 under 50
So candida higher CD4
Lab findings seen in ABPA
Allergic bronchopulmonary aspergillosis
-galactomannan positive
Allergic bronchopulmonary aspergillosis
(a) Imaging findings
(b) Tx
ABPA
(a) CXR: patchy, fleeting infiltrates and lobar consolidation
Late finding/complication of bronchiectasis
(b) Tx = prednisone (systemic ‘roids) + fluconazole
Clinical features of ABPA
Pt w/ known asthma or CF p/w episodic bronchospasm, fever, brown-flecked sputum
Risk factors for aspergilloma
Fungus ball needs an existing pulmonary cavity to grow in => RF include prior Tb, sarcoid, emphysema, or PCP
When to be clinically suspicious for invasive aspergillosis
New pulmonary nodules or persistent fever w/ dry cough despite broad spectrum abx
Severely ill/septic despite broad abx
Invasive aspergillosis
(a) Imaging findings
(b) Serum tests
(c) Tx
Invasive aspergillosis
(a) Air-cresent sign (cavitation of a necrotic nodule) and halo sign (necrotic nodule w/ surrounding hemorrhage)
(b) Galactomannan positive
(c) Tx- surgically remove any fungal balls. Meds- voriconazole, amphotericin, or caspofungin
42 y/oM w/ AIDS (CD4 55) p/w headache and fever, opening pressure of 25 mmHg on LP
Dx?
Cyptococcus neoformans (encapsulated budding yeast) - RF is immunocompromised (vs. coccidioidomycosis which is endemic to SW US and central cali and in immunocompetent)
Buzzword: India ink prep of CSF w/ budding yeast
India ink prep- think cryptococcus neoformans (immunocompromised)
Elderly non-smoker F p/w cough, malaise
CXR w/ middling nodular bronchiectasis
Dx?
Lady Windermere syndrome seen in MAC (mycobacterium avium)
42 y/oF s/p lung transplant 1 yer ago p/w new lung nodule. Biopsy of nodule grows weakly acid-fast bacteria in branching rod pattern
(a) Dx
(b) Tx
(a) Nocardia = gram positive branching rod, weakly acid fast
(b) Tx = TMP-SMX
35 y/oF who immigrated from India 10 yrs ago has routine PPD at 20mm induration.
Denies fever, cough, wt loss, had BCG vaccine as a child
Next step?
BCG vaccine does not affect decision to treat so r/o active disease w/ CXR, then treat for LTBI
**do not consider previous BCG vaccination status when interpreting reactive PPD b/c persistent reactivity is unlikely after 10 yrs
What percent of LTBI develop active disease?
10% total
5% in the first 2 years of infection, then 5% over the rest of their lifetime
Type of isolation required for MTb
Respiratory isolation = negative pressure room, N-95 masks
vs. droplet which is for flu and is just private room w/ face mask
What changes in the 4 drug regimen for Tb are required for its on methadone?
Rifampin is a cyt p450 inducer => use rifaxamin instead when have another cyt p450 med (methadone, protease inhibitor, NNRTI, OCPs)
Name medications that should be taken in caution w/ rifampin
Meds metabolized by cyt p450
Methadone, OCPs, itraconazole, NNRTIs, protease inhibitors
(hence why difficult to treat ppl on HAART for LTBI- so use rifabutin instead of rifampin)
How to distinguish dermatologic manifestations of chickenpox from
(a) Smallpox
(b) HSV
(c) Meningococcemia
(a) Smallpox- all the same stage (while chickenpox are present at multiple stages simultaneously). Also chickenpox relatively spares the extremities
(b) HZV- similar appearing, need to differentiate by Tzank smear
(c) Meningococcus- petechiae, purpura, sepsis
Tzank smear used to diagnose what?
Thank smear of base of vesicle to differentiate VZV (chicken pox/shingles) from HSV
Ramsay Hunt Syndrome
(a) Cause
(b) Clinical triad
Ramsay Hunt syndrome = (a) Herpes zoster opticus (VZV)
(b) Thought to be a polycranial neuropathy from VZV reactivation
1. ipsilateral facial paralysis
2. ear pain
3. vesicles in ear
- can also see hearing problems, lacrimation issues
Ramsay Hunt Syndrome
(a) Cause
(b) Clinical triad
Ramsay Hunt syndrome = (a) Herpes zoster opticus (VZV)
(b) Thought to be a polycranial neuropathy from VZV reactivation
1. ipsilateral facial paralysis
2. ear pain
3. vesicles in ear
- can also see hearing problems, lacrimation issues
Meds to continue when CSF gram stain grows strep pneumo
Continue vanc/CTX until sensitivities return given risk of CTX-resistant strep pneuma
Then of course IV dex x4 days
Tx for 65 y/oM w/ indwelling foley, no urinary symptoms.
UCx growing >100,000 CFU pan-sensitive E. Coli
No tx
Only treat asymptomatic bacteuria in pregnant F
Abx therapy for culture proven listeria meningitis
Ampicillin (or PCN) w/ aminoglycoside (gentamicin) for synergy
Amp + gent
68 y/oF w/ dysuria, foamy vaginal discharge, and punctate-appearing cervix
(a) Dx
(b) Diagnostic test
(a) vaginitis, foamy vaginal discharge, ‘strawberry’ cervix = trichomonads
(b) Vaginal fluid microscopy for motile trichomonads
Prosthetic joint infection bugs
Early vs. late
Early (within 3 months of surgery): MC is staph aureus
After 3 months: MC is coag. negative staph (staph epi)
Bactrim ppx use in AIDs its for PCP vs. toxo ppx
PCP- can be one DS or SS tab daily
Toxo with positive toxo IgG - one DS tab daily once CD4 reaches under 100
When to start HAART on HIV+ pt w/ CD4 350-500
NOT once drops below 350, new guidelines say start HAART on everyone, regardless of cd4 count
Starting it despite CD4 count decreased sexual transmission and HIV-related complications (ex: extra pulmonary Tb)
Odynophagia and dysphagia
(a) immunocompromised
(b) immunocompetent
(a) Candida esophagitis- empiric tx w/ fluconazole, can proceed to endoscopy if inadequate response
(b) Immuncompetent- these are warning signs! straight to endoscopy w/ biopsy and test for HIV
Empiric abx for community-acquired diverticulitis complicated by abcess
Zosyn (pip-tazo) given good coverage for gram negative aerobes, gram positive strep species, and anaerobes
Don’t need vanc (MRSA) or fluconazole (candida) for community acquired
Herpes zoster ophthalmicus
(a) Etiology
(b) Treatment
(a) Reactivation of VZV in the ophthalmic division of the trigeminal nerve- vesicles on tip of nose, periorbital
(b) Tx: oral valacyclovir or famcyclovir, better absorbed and not 5x daily like acyclovir
but IV acyclovir if immunocompromised
Abx of choice for dental procedure ppx
(a) If PCN allergy
First line- PO amoxicillin (strep coverage)
(a) PCN allergy- use clinda
Vaccine/immune globulin choice for 18 y/o w/ dirty wound and unknown immunization history
- TDap (preferred over TD)
2. tetanus immune globulin given dirty wound
Abx ppx to offer adult F victims of sexual assault
CTX, flagyl, azithro cover gonorrhea, trichomonas, and chlamydia respectively
And then HIV PEP
- CTX can cover syphilis, benzaprine/PCN not indicated given low prevalence syphilis
- no acyclovir
