PANCE Prep- Infectious Disease Flashcards
Anti-pseudomonal PCNs
- Piperacillin/Tazobactam (Zosyn)
2. Ticarcillin/Clavulante (Timentin)
Describe examples and reasons for different cephalosporins
1st gen: skin, soft tissue: Cephalexin
2nd gen: skin, resp./ENT, UTI, anaerobes: Cefuroximen, cefoxitin
3rd gen: PNA, CNS, gram neg: Ceftriazone, Ceftazidimine
4th gen: Cefepime (broad coverage including pseudomonas)
5th gen: ceftaroline (broadest)
Common SE of penicillins and ampicillin
- hypersensitivity rxn
- interstital nephritis
-amp: maculopapular rash in patients w/ infectious mononucleosis
Common SE of cephalosporins
10% cross reactivity in pts allergic to PCN
- Disulfiram raction
Common SE of vancomycin
Red man syndrome (Histamine release)
-Ototoxic (reversible)
Common SE of macrolides
- GI upset
- prolonged QT
- muscle toxicity fo those on niacin or statins
Common SE of fluroquinolones
- tendon rupture
- exacerbate myasthenia gravis
- prolonged QT
Common SE of Clindamycin
- c. difficiles colitis
Common SE of tetracycline
- deposition in teeth, teeth discoloration
- photosensitivity
Common SE of sulfonamides
- kernicterus
- sulfa allergy
- hemolysis if G6PD def.
Common SE of Metronidazole
- Avoid ETOH during and 48 hr after
- Disulfiram-like rxn
- Neurotoxicity
What PCN has the highest occurrence of diarrhea
augmentin
TX of:
- Esophagitis
- Vaginal Candidiasis
- Fungemia, Endocarditis
- Esophagitis: Fluconazole PO
- Vaginal Candidiasis: Miconazole, Clotriamazole
- Fungemia, Endocarditis: IV AmphotericinB
MC cause of fungal meningitits
Cryptococcosis neoformans (encapsulated
*Transmission: inhalation of pigeon/bird droppings
- DX: India Ink stain shows encapsulated yeast
- Cryptooccal antigen in CSF
TX: Amphotericin B + Flucytosin
AIDS-defining illness associated w/ soil containing bird/bat droppings in the Mississippi and Ohio River Valleys
Histoplasmosis
DX: Increased ALP, LDH, pancytopenia
TX: mild-mod: Itraconazole
Severe: Amphotericin B
MC opportunisitc infection in HIV
-O2 desaturation w/ ambulation
CXR: bilateral diffuse interstital infiltrates
Pneumocystis (PCP Pneumonia)
TX: Trimethoprim-sulfamethoxazole**
+/- Prednisone if hypoxic
PCP Prophylaxis: trimethoprime-sulfamethoxazole if CD4 200 or less
This fungus is commonly found in garden and houseplant soil and compost. It MC affects lungs, sinuses, and CNS. it produces Aflatoxin which is associated with an increased risk of hepatocellular carcinoma
Aspergillosis
MC overall bacterial cause of STDs in US
Chlamydia
- Urethritis
- PID, abdominal pain, + cervical motion tenderness
- (urethritis, uveitis, arthritis)
Chlamydia
DX: Nucleic acid amplification (test of choice for C and G)
TX: azithro. 1g x1 dose or doxy 100mg BID x 10 days
*retest in 3 weeks
*Tx w/ ceftriazone 250mg IM x 1 dose for G infection too
gram-neg diplocci
- MC cause of urethritis in men
- urethritis and cervicitis: anal, vaginal, penile or phargyngeal discharge
Gonorrhea
DX:DX: Nucleic acid amplification (test of choice for C and G)
TX: ceftriazone 250mg IM x 1 dose
*tx w/ azithro. 1g x1 dose or doxy 100mg BID x 10 days for additional C. coverage
Cause and Tx of Cat Scratch Disease
Bartonella henselae
TX:
mild- symptomatic tx** (resolves in 7-21 days)
mod: azithro or doxy
Empiric tx, tx of choice, and prophylaxic for Meningococcal meningitis
*Neisseria meningitidis
Empiric:
adults- Ceftriaxone + Vanco
infants- Cefotaxime + ampicillin
if susceptible: Penicillin G
Prophylaxis/exposure: Cipro 500mg x 1 dose or Rifampin
Describe Kernigs sign and Brudzinskis sign
Kernigs: inability to straighten leg when hip is flexed 90
Brudzinski: neck flexion causes involuntary hip/knee flexion
Chancroid causes painful genital ulcers–> bubo formation (enlarged lymph nodes)
what organism is it caused by and how do you tx
Haemophilus ducreyi
TX: azithro 1g x 1 dose
Haemophilus influenza MC causes what diseases
MC cause of epiglottitis
2nd MC cause of CAP
*often associated w/ sinusitis and AOM
how do you t H. influenza infection
amoxicillin
IV ceftriaxone for epilottitits, PNA or meningitis
Cause and tx of hot tub foliculitis
Cause: pseudomonas aeruginosa
TX: resolves spontaneously in 7-14 days w/o tx
-Ciprofloxacin orally if persists
how do you dx and treat Q fever
*Coxiella burnetii- exposure to sheep, goats, cattle, and their products (wool)
DX: immunofluorescence IFA
TX: doxycycline
Cause of the plague, Dx, and TX
Cause: Yersinia pestis (gram neg rod)
DX: gram stain from tissue- “saftey pin appearance of organisms”
TX: streptomycin or gentamicin
*respiratory isolation for at least 48 hours
MC cause of necrotizing fasciitis (flesh eating bacteria) and tx
GABHS (often polymicrobial)
TX: surgical debridement + broad spectrum Abx (ampicillin/sulbactam- unasyn)
Tonsillopharyngitis or laryngtitis
- pseudomembranes: friable gray/white membrane on pharyns taht bleeds if scaped
- Bull neck*- neck swelling due to enlarged cervical LAD
- myocarditis
Diptheria
(Corynecbacterium diphtheriae) gram positive rod
How do you dx and tx diptheria
DX: clinical- PCR- culture to confirm
TX: Diphtheria antitoxin (horse serum) most important + Erythromycin or PCN x 2 weeks
Prophylaxis: erythromycin x7-10 days
DTaP
severe muscle spasm
- neck/jaw stiffness, trismus= lockjaw
- Opisthotonus (arched back)
- increased deep tendon reflexes
Tetanus
TX:
- Tetanus immune globulin immediately
- Tetanus toxoid given by standard schedule
- Penicllin
- benzo to reduce spasms
Prophylaxis: Tdapq 10 yrs
Systemic toxicity
-brown to blood tinged watery exudates w/ skin discoloration of the surrounding area
- Creptius/gas in the tissue palpated on PE
XRAY: air in soft tissues
Gas Grangrene (myonecrosis)
TX: IV pencillin + IV clindamycin (debridement)
Ingestion of toxin in canned/smoked/vacuum packaged foods
or infant ingests honey
-weakness, flaccid paralysis, resp. arrest
or get “Floppy baby syndrome”
Botulism
*Clostridium botulinum
TX: Antitoxins in all gases
What are the 8 D’s of botulism?
- Diplopia
- Dilated, fixed pupils
- Dry mouth
- Dysphagia
- Dysarthria
- Dysphonia
- Descending 8. Decreased muscle strength
endotoxin-producing, gram positive bacilli
MC found in contaminated foods (cold deli meats, unpasteurized dairy products (soft cheese, milk)
Listeriosis
*Listeria monocytogenes
TX: IV ampicillin
- Gram-positive , spore-forming rod
- Naturally found in livestock: cattle, horses, goats, sheeps
- PAINLESS BLACK ESCHAR
- hypoxia, flu like sx
- GI bleeding, abdominal pain
- Gram stain: boxcar-shaped encapsulated rods in chains
Anthrax
TX: ciprofloxacin (use for exposure too)
What organism cause syphilis
Treponema pallidum (“the great imitator”)
Describe primary, secondary, and tertiary syphilis
Primary: chancre: PAINLESS ulcer at/near inoculation site
Secondary (1-2 months after primary):
- maculopapular rash (involves palms and soles)***
- Condyloma lata: wart like
- HA, fever, malaise generalized LAD
Tertiary: gumma- noncancerous granulomas on skin and tissue
- neurosyphilis w/ Tabes dorsalis
- Argyll-Robertson pups
- CV: aortitis
s/s of congenital syphilis
Hutchinson teeth: notches on teeth, sensorineural hearing loss
-Saddle nose deformity
TORCH syndrome
How do you dx and tx syphilis
DX:
- darkfield microscopy (use w/ chancre or condyloma lata)
- RPR screening-
- FTA-ABS confirmation test***
- VDRL
TX: penicillin G (used in all stages)
-Erythema migrans
-expanding, warm, annualr, erythematous rash w/ central clearing or bulls eye appearance
-Rheumatologic arthritis
CN VII/facial nerve palsy
Lyme disease (Borrelia burgdorferi)
DX: Clinical
-Serologic testing: ELISA follwed by western blot if positive
TX: Doxy BID 10-21 days or amox. if <8y/o or preg.
- blanching, erythematous macular rash first on wrists/ankles==> palms/soles characteristic and spreading centrally over 2-3 days
- petechiae
- spread by ticks
- potentially fatal if left untreated- CNS or resp. failure
Rocky Mountain Spotted Fever
*Rickettsia ricketsii
DX: clinical dx–> serologies
TX: *start treatment empirically before serologies come back (takes days) doxycycline**
Tx of amebiasis
colitis: metronidazole
- RBC disease caused by Plasmodium*
- Cyclical fever, leukopenia, hemolytic anemia, thromboyctopenia, N/V,
- Recent travel to Africa
Malaria
DX: Giemsa stain peripheral smear (thin and thick)
TX:
- uncomplicated cases when resistance is unknown: atovaquone-proguanil
- those who are sensitive:Chloroquine
blueberry muffin rash, hepatosplenomegaly, hearing loss, mental deveopment delay
- common in immunocompromised pts CD4<100
- MRI: ring-enhancing lesions
Toxoplasmosis
TX: sulfadiazene (or clindamycin) + Pyrimethamine (w/ folinic acid/leucovorin)
Prophylaxis for CD4=100, trimethoprime-sulfamethoxazole
- leading cause of CHF in Latin America
- unilateral periorbital edema (Romana’s sign)
- CHF, cardiomyopathy, Megacolon
Chagas disease (American Trypanosomiasis) *protozoa Trypanosoma cruzi
Transmitted by raw or undercooked meat (esp. PORK, wild boar or bear)
-GI upset
-Muslce phase: myositis, palpebral/circumorbital edema
DX: **Eosinophilia hallmark: increased creatine kinase and LDH
Trichinosis (Trichenellosis)
TX: mild- self limited
severe- Alendazole
Periorbital edema, myositits, and eosinophilia
Trichinosis (Trichenellosis)
prodromal sx 24 hr prior (burning, paresthesias, tingling)–> painful grouped vesicles on an erythematous base
herpes simplex virus 1 and 2
DX: PCR most sensitive and specific
2. Tzanck smear
TX: acyclovir (IV for encephalitis)
genital herpes is most commonly caused by ___
herpes labialis is most commonly caused by ___
HSV2
2ndary infection most often
- Present in most people in the US–> clinical disease only in immunocompromised patients
- Primary disease: asymptomatic or Mono-like illness
- Congenital: **sensorineural hearing loss, TTP blueberry rash, petechaie
CMV
DX: serologies, PCR
TX: Ganciclovir
- vesicles on an erythematous base “dew drops on a rose petal” in different stages*
- itchy
varicella (chicken pox)
TX: symptomatic tx
-vesicles along dermatome
herpes zoster (shingles)
TX: acyclovir if given w/in 72 hours to prevent PHN
lesion on nose usually heralding ocular involvement, dendritic lesion seen on slit lamp
Herpes Zoster ophthalmicus
TX: PO antivirals
otalgia, lesions on the ear, auditory canal and tympanic membrnae, facial palsy, auditory sx
herpes zoster oticus (Ramsay-Hunt Syndrome)
TX: oral acyclovir + corticosteroids
Fever
Sore throat
Posterior cervical lymphadenopahty
splenomegaly
EBV (mono- HHV4)
DX: heterophile (monospot) Ab test
-peripheral smear w/ >10% atypical lymphocytes
TX: supportive- avoid trauma/sports
You may develop a petechial rash if you have mono and are given ____
ampicillin
what animals do you typically get rabies from
raccoons, bats, skunks, foxes, wolves
*not rodents
How do you dx and tx rabies
DX: Negri bodies in brain of dead animal
TX: *once sx occurs pts rarely survive
Post exposure prophylaxis:
- HDCV (rabies vaccine x 4) days 0, 3, 7, 14 + rabies immune globulin
- if immunocompromised include day 28 into vx schedule
- flu like prodrome: abrupt onset of high fever and severe head/back pain*
- skin eruptions in the same stage simultaneously*
- palmar and plantar lesions common
smallpox (variola)
What causes West nile fever and how do you tx
Flavivirus
TX: intense supportive
What causes SARS and how do you dx
(non-specific flu-like sx
-atypical pneumonia*)
coronavirus
DX: PCR, stool is the 1st to be positive w/in 14 days
tx: supportive
rapidly progressive dementia
creutzfeldt-jaob disease (prion mediated)
what type of virus is HIV
retrovirus (changes viral RNA into DNA via reverse transcriptase)
AIDS is defined as
CD4 count <200 or the development of an AIDS defining illness
(TB, kaposi sarcoma, Thrush, lymphoma, zoster, PCP, Histoplasmosis, Toxoplasmosis, cryptococcus, MAC, CMV retinitis)
how do you DX HIV
- ELISA (screening)- if reactive confirmed by western blot
- western blot
- HIV RNA viral load
What opporunistic infections are susceptible with different CD4 counts 700-1500 >500 500-200 200 or less 150 or less 100 or less 50 or less
700-1500: normal >500: LAD 500-200: TB, kaposi sarcoma, thrush, lymphoma, zoster 200 or less: PCP, 150 or less: histoplasmosis 100 or less: toxoplasmosis, cryptococcus 50 or less: MAC, CMV retinitis
HAART regimens for treatment naive patients w/ HIV
- NNRTI (non-nucleoside reverse transcriptase inhibitor) + 2 NRTIs (nucleostide reverse transcriptase inhibitor)
OR - Protease inhibitor + 2 NRTIs
OR - Integrase strand transfer inhibitor + 2 NRTIs
3Cs of rubeola
(measles)
Cough, coryza, conjunctivitis
- Koplik spots on buccal mucosa
- maculopapular BRICK RED rash beginning at hair line/face–> extremities. (last 7 days)
- cough, rhinitis, conjunctivitis
Rubeola (measles)
- maculopapular pink-light red spotted rash on face–> extremities (lasts 3 days)
- post cervicla and postauricular LAD
- photosensitivity and arthralgias
Rubella (German measles)
- Pink maculopapular blanchable rash
- only childhood viral exanthema that starts n trunk/extremitites then goes to face
- high fevers but appears well
Roseola (6th disease)
- red flushed face slapped cheeks w/ circumoral pallor–> lacy reticular rash on body
- aplastic crisis in sickle cell disease
erythema infectiosum (6th disease) *parvovirus B19
- Flushed face, hearing loss (CN8), conjunctivitis
- maculopapular rash trunk and axilla
endemic typhus
- fluid filled blisters w/ positive Nikolsky sign: sloughing of skin with gentle pressure
- painful diffuse red rash begins centrally
- seen in kids <6
Scalded skin syndrome
- White and clumpy itchy vaginal discharge s/p antibiotic treatment for something else
- No hx of STD nor does partner have one
-What is the Dx and how do you tx?
DX: vulvovaginal candidiasis
-confirmed by 10% KOH wet mount
TX: topical or oral antifungal (Fluconazole 150mg 1 tablet once)
How do you treat:
- Bacterial vaginosis
- Trichomoniasis
- vulvovaginal candidiasis
- chlamydia
- gonoccal infection
- BV: metronidazole
- Trichomoniasis: metronidazole
- vulvovaginal candidiasis: antifungal (topical or oral fluconazole/difulcan)
- chlamydia: azithromycin
- gonoccal infection: Ceftriaxone
HIV patient w/ SOB, cough and feeling of “catch” on inspiration
- PPD negative
- CXR: lobar infiltrates
- CD4 count is 500
What is the most likely etiology?
Streptococcus pneumoniae
What is the prophylaxic treatment for the following opportunistic infections and when do you initiate them?
- PCP:
- Toxoplasma:
- Mycobacterium avium:
- CMV:
- Mycobacterium tuberculosis:
- PCP: trimethoprim/sulfamethoxazole (when CD4 below 200 or recurrent thrush)
- Toxoplasma: trimethoprim/sulfamethoxazole when CD4 <100
- Mycobacterium avium: azithro or clarithro
- CMV: below 50-75
- Mycobacterium tuberculosis: Rifampin
- Immunocompromised patient with fever, general malaise lymphadenopathy, productive cough, chest pain, weight loss
- CXR: Solitary or multiple nodules on
Cryptococcosis
Dx confirmed w/ India ink prep or histologic tissue stain
TX: oral or parenteral antifungals
presents w/ productive (yellow) cough and SOB and low grade fever but otherwise healthy
- Works in bat caves
- CXR: cavitary lung lesions
What is the most likely diagnossi
Histoplasmosis
*Caught/found in soil, decaying wood, bird droppings, bats
- Fever, abdominal cramps, diarrhea (sometimes with blood)
- consumed raw eggs
salmonella enteritidis
TX: supportive- self limiting
- Fever, abdominal cramps, bloody diarrhea,
- High fever causing a seizure
Shigella
TX: supportive care
(Shigella and salmonella poisonings include same sx but salmonella does not cause seizures)*
How can you differentiate shigella from salmonella poisoning?
*both poisonings have Fever, abdominal cramps, bloody diarrhea
Shigella and salmonella poisonings include same sx but salmonella does not cause seizures
How is Vibrio cholerae transmitted? what are the sx? how is it tx?
- through wounds
- eating undercooked shellfish
- drinking contaminated water
sx: profuse, watery (non-bloody) diarrhea that can lead to dehydration, low grade fever, abdominal cramps
TX: Azitho or doxycycline
- Gray pseudomembranes on tonsils**
- congestion, sore throat, low grade fever, (TMs clear, lungs clear)
- H/o Lack of medical care (missed childhood vaccines)
Corynebacterium diphtheriae
TX: parenteral PCN or erythromycin
Causes of bloody diarrhea
- Salmonella
- Shigella (can cause febrile seizures)
- Entamoeba histolytica (sexually transmitted)
This organism enters the skin and travels to the lungs. It then migrates into the mouth, are swallowed, and reproduce in the gut. They cause bleeding and subsequent anemia. Can also cause absorption problems
What is this organism? How do you dx and tx?
Hookworms
DX: microscopic analysis of stool
TX: albendazole
- Fever, coryza, conunctival involvment
- prodrome dissipates as the characteristic rash develops first on HEAD and face and then on trunk
- white spots on buccal mucosa
measles
*white spots= Koplik spots
another name for roseola and what is it caused by
erythema subitum
HHV-6
Tx of an abscess in a diabetic
I&D + Abx (clindamycin, bactrim, doxycycline, or linezolid)
How do you Dx and TX H. pylori and how would you test for successful treatment
DX: urease breath, fecal Ag, serology
TX: CAP
- clindamycin
- Amoxicillin
- PPI
Test of cure: stop PPI 1-2 weeks prior to fecal Ag or breath tests
*PPIs are less likely to interfere with serology test
What is the drug of choice for TB prophylaxis
Isonizide daily for 9 months
*risk of hepatitis so check LFTs during coarse
mycoplasma pneumoniae can only be diagnosed by
PCR
treatment of Legionnaire’s disease (Legionella PNA)
Gram neg.
In immunocompetent host: azitho 500mg daily or clarithromycin 500mg BID or levofloxacin 750mg daily for 10-14days
- SOB and cough
- fever 4-5 days, malaise, muscle aches, HA
- h/o working or being around RODENTS
- CXR: Pulmonary edema
- Labs: increased WBC, elevated hematocrit,, LDH, ALT and AST
Hantavirus
*rodent vector and usually manifest in hemorrhagice fever or Hantavirus pulmomary syndrome (rapidly progresses to resp. distress syndrome)
What are Dengue and yellow fever caused by
Flaviviridae (Carried by mosquitos)
Filoviruses causes ___
Ebola fever and Marburg fever
What is typhoid fever caused by
salmonella typhus (contracted by contaminated food or water)
Abdominal distention, constipation followed by diarrhea, splenomegaly, blanchable pink papular rash over the trunk and fever
+ blood cultures
typhoid fever
Begins w/ fever and constitutional sx and in its more advanced form includes bradycardia, hypotension and jaundice
yellow fever (Flaviviridae)
Presents w/ episodic bouts of high fever, chills, and sweats, separated by relatively asymptomatic periods
-infection progressed, other body systems may be involved including possible seizures
Malaria
Brucellosis can be caused by exposure to ____
hogs, cattle or goats
- Exposure to parakeets*****
- fever, chills, HA, deep dry cough, atypical pneumonia sx
psittacosis
TX: tetracycline
