Infectious Disease Factoids Flashcards
Prodrome with then sudden onset pruritic and erythematous swelling of the hands/feet that is well-demarcated at the wrists and ankles; also painful pruritic petechiae, papules on the hands and feet.
What is the name of the disease and what infectious agent causes this?
Papular Purpuric Gloves and Sock Syndrome (PPGSS).
Caused by Parvovirus B19.
Lab finding associated with Bordetella pertussis?
Lymphocytosis
Mosquito-borne illness, summer-time, that can cause meningitis/encephalitis symptoms and fever; CSF with primarily lymphocytosis; a bunch of birds have died in the nearby area.
West Nile Virus (Arbovirus)
Swimmer’s ear, otitis externa. Etiology?
Pseudomonas aeruginosa
Functional or anatomic asplenia in an infant ; what vaccine should you consider?
Meningococcal vaccine- give 4 doses of a quadrivalent vaccine; high incidence of invasive N. meningitidis in infants <1 year of age.
Ocular prophylaxis with erythromycin in infants protects against perinatal transmission of which organism?
N. gonorrhea (does not protect against Chlamydia trachomatis)
Ophthalmia neonatorum within 2-5 days of life etiology? Onset at after that?
First- gonorrhea
Second- chlamydia
If within 24 hours of birth chemical conjunctivitis
Late Lyme disease symptoms
Mono or poly-articular arthritis of the large joints (esp. knees) with swelling larger in proportion compared to actual pain experienced.
How long does it take for Borrelia to transmit from tick to human?
> 36 hours, can just do observation if less than that
What is the most common viral cause of meningitis?
Non-polio enteroviruses (coxsackie, echoviruses, enterovirus); meningitis (nuchal rigidity/photophobia) vs meningoencephalitis (AMS)
How long should patients avoid contact sports after being diagnosed with EBV infection?
Should not be cleared for at least 3 weeks or until splenomegaly has resolved (usually 1-3 months after onset).
Treatment for rabies if animal cannot be captured and observed vs. captured.
Clean wound, need Rabies Ig one dose at and around injection site, vaccine at a different site on same day, day 3/7/14. If can be captured and found not to be rabid, then no need for treatment.
Which group at highest risk for INH associated peripheral neuropathy?
Vegetarian (non-meat/non-dairy) because does not have Vit B6 (pyridoxine).
Treatment of ophthalmia neonatorum if asymptomatic vs symptomatic born to a mother +gonorrhea?
Asymptomatic– Ceftriaxone IM 50mg/kg x1
Symptomatic– CTX 50mg/kg x7 days
How long is someone with Varicella infection contagious?
1-2 days before rash onset until the rash crusts over.
Contagious period for measles?
Four days before and four days after onset of rash. AKA Rubeola.
Varicella post-exposure Ig?
Babies born to MOP diagnosed with VZV 5 days before and 2 days after birth–because less chance of transplacental transfer of maternal Varicella Ig and other immunocompromised (pregnant, pre-term infants)…
Nagayama spots? What disease is this seen with this? What does the rash associated with this disease look like? What are other findings seen in this disease?
Macules/ulcerations at the junction of the soft palate and uvula; Roseola infantum (HHV-6); small raised palpable and blancheable lesions along trunk/proximal extremities/face after high fever breaks; eyelid swelling, conjunctivitis
Infectious mononucleosis pathology finding?
Atypical lymphocytes (basophilic stippling and foamy-appearing cytoplasm)
Infectious Mono clinical signs?
Exudative pharyngitis, conjunctivitis, periorbital and eyelid swelling
Parvovirus rash is called erythema ______? Should a pregnant woman avoid a child with a parvovirus rash?
Infectiosum; CDC does not recommend that pregnant women isolate from parvoB19 b/c of low risk of fetal complications (hydrops?); when rash appears, they are not contagious
Rash with sharply demarcated edges?
Strep toxin mediated erysipelas (usually Strep pyogenes or Group A strep)
Chronic draining lesions with a formed sinus draining tract, not responsive to antibiotics
Non-tuberculous mycobacterium (avium complex for purple pre-auricular LAD; marinum for post water exposure abscesses)
Neonatal Listerosis CSF WBC differential?
Increased # of monocytes (Listeria MONOCYTogenes); usually MOP has a flu-like illness
Vesicles along anterior 2/3 of the tongue, pinna, facial nerve palsy; name of condition and etiology of infection? Do you treat?
Ramsay-Hunt syndrome; VZV reactivation of the geniculate ganglion (manifestation called herpes zoster); treat with glucocorticoids and acyclovir because of risk of permanent facial nerve palsy or impairment
Etiologies of bacterial meningitis per age group?
1-3 months of age?
3 mo - 10 years of age?
Older children - adolescents?
1 - 3 months– GBS (S. agalactiae) and E. coli
3 mo - 10 years– Strep pneumo, N. meningitidis
Older children/adolescents– N. meningitidis
Lemierre’s disease? What is a complication?
Suppurative thrombophlebitis of the jugular vein due to extension of an oropharyngeal or dental infection (manifest as trismus, neck pain/stiffness); complications include septic emboli
Causes of epiglottitis and empiric therapy?
Use to be H. influenza, but now more commonly GAS, S. pneumoniae and S. aureus; so empiric therapy would be Vancomycin (S. aureus, resistant-strep) and CTX (H. influenza)
Etiologies of osteomyelitis/discitis?
S. aureus- most common cause (you may only have a positive blood culture 50% of the time)
Kingella (<5 years old)
Treatment of Staph osteomyelitis?
IV therapy 1-2 weeks, followed by oral therapy for 5-6 weeks.
Creeping eruption on lower extremities after playing in the sand/soil or at the beach? What is the treatment for this?
Ancylostoma braziliense (dog and cat hookworm)– albendazole)
Blistering dactylitis of volar fat pads (large tense blisters?)
Group A Strep most common, then Staph
Congenital varicella syndrome features?
Shortened limbs, micro-ophthalmia, cataracts/chorioretinitis, scarring over previous cuts in a dermatomal distribution– infection in the first trimester
Neonate exposed to pertussis; post-exp prophylaxis?
Azithromycin 10mg/kg BID x5 days; other people who received vaccine should not have an issue
Subacute bacterial endocarditis vs. acute bacterial endocarditis etiology? Different presenting symptoms?
SBE- strep viridans
ABE- staph
Signs- Osler nodes, Janeway lesions, Roth spots (retinal exudative hemorrhages), splinter hemorrhages (nailbeds)
Usually history of a valve/cardiac issue
N. meningitidis sepsis most common in which patient population?
Terminal complement deficiency
N. meningitidis PEP?
Rifampin 10mg/kg PO BID or
CTX single IM injection (125mg if <15y/o; 250mg if >15 y/o)
Cipro 20mg/kg x1 dose > or = 18 yrs old
Eradicate nasopharyngeal Neisseria
Congenital Rubella Syndrome Features?
Sensorineural hearing loss; blueberry muffin rash; congenital cataracts; PDA murmur if infected within the first 8 weeks?
Staph associated Toxic Shock Syndrome acquisition?
Can occur in boys AND girls; Staph infection through a wound, tampons, complication of surgical wound/packing
Features of SSSS?
Labile vitals (hypotension) due to toxin;
erythroderma/mucosal involvement;
respiratory (SHOB)/GI (vomiting/diarrhea)/ DIC/ heart or renal failure
Treatment of SSSS?
Clindamycin (slow down toxin production) + Vanc (MRSA)/Nafcillin (MSSA)
Granulomatosis infantiseptica etiology?
Listeria monocytogenes
Common medications (2) for malaria prophylaxis?
Chloroquine or Doxycycline if travel to area with high resistance to chloroquine (start 1-2 days before once daily, continue through travel and then 28 days after travel complete).
Papular acrodermatitis of childhood?
Commonly caused by viruses during acute infection or after vaccines; EBV common cause; flesh-colored non-umbilicated papules over face and extensor surfaces of arms and legs (spares the trunk)
PANDAS- features and etiology?
Pediatric Autoimmune Neuropsych Disorders associated with Strep infection; increase OCD/tic disorder and other neuro symptoms after strep infection
Multinucleated giant cells on Wright stain; what infectious agent causes this?
Herpes Simplex (AKA Tzanck smear)
Treatment for primary vs latent or tertiary syphilis?
Primary syphilis: pencillin G benzathine 2.4 million units IM x 1 dose
Tertiary/latent syphilis: Pen G Benzathine 2.4 million Units IM once q week x3 weeks
Haemophilus ducreyi presentation?
Painful/tender ulcer with a gray, fibrinous membrane with buboes (painful swollen LAD in groin/arm pits)
How do you diagnose HIV in an infant?
HIV DNA/RNA PCR at 14-21 days, 1-2 months, 4-6 months of age (need at least 2 virologic tests on separate occasions) if <18 months old; if 18mos or older, HIV antibody tests (by this time, MOP’s antibodies will have cleared from infant)
Contraindications to breast-feeding?
Active TB, HIV, chemotherapy or radiation therapy, anti-retroviral therapy
Toxic Shock Syndrome etiologies and mechanisms of infection? Difference between two different etiologies?
Toxin-mediated reaction due to Staph or GAS– effect on at least three or more organ systems (CNS- AMS, CV-hypotension/vital sign changes, GI- nausea, vomiting, diarrhea; skin/mucosa– erythroderma/straetc..)
Mechanisms: burn, wound from environment, nasal packing, tampons, indwelling catheters, surgical wounds.
Differences between two etiologies: Staph–significant erythroderma (usually don’t see that with GAS)
Retinal lesions you see in bacterial endocarditis?
Roth spots (fibrin deposits in the center of retinal hemorrhages)
Source of sore throat, fever and pruritic rash, rapid strep and throat culture negative, rapid mono negative. Culture shows gram-positive rod that grows only in blood-enriched media. Identify the bacteria.
Arcanobacterium haemolyticum (not an obvious etiology–often missed because hard to grow on culture). Treat with erythromycin (PCN won’t work). No long term effects of non-treatment.
“Alice in Wonderland Syndrome” is associated with which infectious etiology?
Infectious Mononucleosis– distortion of shapes, sizes, colors, spatial relationships; can also have AMS, seizures, ataxia, meningitis/encephalitis, transverse myelitis.
Pre-auricular LAD, bulbar and palpebral conjunctivitis, tonsillar swelling, URI symptoms, hemorrhagic cystitis. Name the virus.
Adenovirus.
What does a double disc diffusion test check for?
Inducible resistance of staph to clindamycin (identification of MRSA). Sensitivity testing of staph aureus. Place discs of clindamycin and erythromycin right next to each other. Forms a D shape (clearing in a circular fashion around Clindamycin disc, except for front between C and E, because E induces Clindamycin resistance in MRSA).
Chemoprophylaxis for meningococcal meningitis?
Single dose- Ciprofloxacin orally, Ceftriaxone IM
Over two days- Rifampin BID for TWO days
Calcifications throughout the brain–etiologies? Also difference between two etiologies based on location of calcifications in the brain?
CMV- CircuMVent the ventricles (periventricular), in a linear fashion
Toxoplasmosis- scattered throughout the brain, especially in the caudate nucleus and basal ganglion
Spiral-shaped gram-negative bacteria that can cause bloody stools?
Campylobacter
True or False. Obtain a blood culture prior to starting antibiotics for bloody diarrhea.
True, want to make sure you are not inadvertently treating and missing a bacteremia, especially if showing systemic symptoms.
Interdigital rash as a result of excessive water exposure–what infectious etiology? If you have a history of seasonal allergies/atopic eczema with an interdigital rash with itchy, fluid-filled blisters, what do you think of instead?
Cutaneous candidal infection
Dyshidrotic eczema
HbsAg+ mother, what do you do for the baby?
<2kg: give vaccine at birth and HBIG, but you DO NOT count it as part of the HepB vaccine series.
>2kg: give vaccine at birth and it counts towards HepB series
If you don’t know mom’s HepBsAg status, give HepB vaccine and can wait to give HBIG within 7 days of birth (when MOP’s HepBsAg results).
Post-exposure prophylaxis for pertussis in a 3 week old that has been exposed?
Can use azithromycin (less risk of idiopathic infantile pyloric stenosis); important to start prophylactic meds as soon as you have exposure, because not effective when in the paroxysmal phase (developed whooping cough).
MMR post-exposure prophylaxis
If greater than or equal to 12 months old, give vaccine within 72 hours of exposure (can count towards vaccine schedule).
If within 6- <12mo, can give vaccine, but will not count towards vaccination series.
Only give measles Ig for very high risk individuals (pregnant women, immunocompromised).
Measles course
Contagious four days before and four days after rash; 3 C’s (cough, coryza, conjunctivitis), Koplik spots on uvula/soft palate 2-3 days prior to rash, then rash starting at head and spreading caudally
Fine pink, papular and somewhat pruritic rash that spares the circumoral area, as well as the palms and soles; name of rash and associated infectious etiology?
Scarlet fever associated with Strep pyogenes (group A strep)
Patients with cochlear implants are at high risk for which bacterial infection? Prophylaxis?
Strep pneumo; PPSV23 at least 8 weeks after receiving all of their PCV13 vaccines (needs only one if immunocompetent)
What type of patients require two PPSV23 vaccines?
HIV, malignancies, asplenia, immunodeficiencies, chronic kidney disease
EBV antibodies and when they rise?
EBV viral capsid antigen IgM- evidence of acute EBV infection (usually peaks within the first 1-2 weeks of acute infection and then becomes undetectable
EBV viral capsid antigen IgG- peaks in the late acute phase of infection and plateaus at low but detectable levels for a while
EBV Early Antigen- not very specific, can be positive in acute primary, recent past, chronic, reactive, EBV-activated malignancies. Often not included in the panels.
Anti-EBNA (nuclear antigen) Igs- evidence of infection from >6 months ago.
Ring abscess in the eye–which bacteria should you think of?
Bacillus cereus (foreign body injury to the eye, especially if has soil or vegetative matter). Also pseudomonas and Proteus.
Rapid mono testing is less reliable in which age group?
Children <4 years old (often do not produce heterophiles antibodies); heterophile antibodies are antibodies to EBV produced by the body that cross-reacts with RBCs of goats/sheep, etc.
Pertussis exposure prophylaxis?
Exposed fully-immunized contacts should receive prophylaxis with azithromycin
Prophylaxis for a newborn of a woman exposed to active Varicella?
Varicella Ig given to infant of a mother who was exposed within five days before or two days after delivery
Argyll-Robertson pupils are seen in which infectious disease?
Neurosyphilis– small pupils that are poorly responsive to light, but react with accommodation
Saddle-nose deformity, periostitis, osteochondritis in an infant is associated with what infection?
Syphilis
What peripheral blood smear finding would you see in a neonate Chlamydia trachomatis pneumonia?
Eosinophilia
Name the infection: retroauricular, posterior cervical and occipital lymphadenopathy in an unimmunized patient with erythematous and petechial spots on the soft palate.
Rubella (Forschheimer spots)
Name the disorder: fever and rash that starts off in the creases (axilla, antecubital fossa, groin).
GAS (Scarlet fever)
Propofol can cause what side effect during use for sedation?
Central/Obstructive sleep apnea.
Need for N. meningitidis post-exposure prophylaxis in what population?
Prolonged exposure ( >8 hours) where contact was within 3 feet of the patient, within 7 days of onset of symptoms and 24 hours after the start of the start of PEP antibiotics.
Also anyone who has come in direct contact with the oral secretions of the patient (intubation or other aerosolizing procedures).
True or False. Measles is an airborne disease.
True– you need N95 respirators and negative pressure ventilation in the patient’s room.
True or False. Rash induced by amoxicillin admin while having infectious mono is due to a hypersensitivity reaction.
False. It is due to amoxicillin-antibody complexes formed after B-cell activation.
Patent PDA and peripheral pulmonic stenosis is associated with which congenital TORCH infection?
Rubella
HiB PEP is indicated for which population?
Children exposed to a positive kid with invasive infection who are:
<12 months old and did not complete their primary Hib series
<48 months old and unimmunized/partially immunized
Any child that is immunocompromised regardless of age
Also any child-care/household contact when 2 or more cases of invasive HiB infections have occurred within 60 days.
Most common cause of recreational water-borne GI illness? What is the treatment?
Cryptosporidium. Nitazoxanide.
Name the disease: premature infant (<35 wks) born within 24 hours of life, respiratory distress with CXR showing streaking infiltrates, maternal flu-like illness preceding birth, born through green/brown tinged fluid.
Neonatal listerosis (early– because it presented within the first week of life), sepsis-like picture of infant, skin manifestation (granulomatosis infantisepticum)
How does late neonatal listerosis present?
Term infant, usually after second week of life
Non-specific illness syptoms– usually presents as a meningitis
How does neonatal E. coli infection usually present?
Bacteremia
Latent TB in mothers and management of infant?
Latent TB for mother– start INH for mother for at least 9 mo and breast feed baby, no need to treat baby or separate baby from mother
Active TB in mother and management of infant?
Separate mother and baby until both have been started on treatment, at about 3-4 month mark, reassess baby’s PPD–> (1) if negative PPD, okay to finish off INH x9 months; (2) if positive PPD, need to reassess for active TB disease; hold off on breast-feeding until at least 2 weeks of INH treatment
