Infectious Disease Flashcards
Tonsillar pharyngitis
Posterior cervical lymphadenopathy
Fever
+maculopapular rash after amoxicillin or ampicillin administration
What is it?
EBV
Not a true allergy! Ok to take drug later
Common pathogens in cystic fibrosis related PNA
Gm - rod
- P. aeruginosa
- Burkholderia cepacia
- Stenotrophomonas
Hib, nontypeable
Strep pneumo
Staph aureus
Child with:
- fever
- rash (maculopapular) starting on face –> trunk and extremities
Prior to rash:
- cough
- coryza
- sneezing
- tearing
What is it?
What has been shown to reduce morbidity and mortality rates of pts w/ this infection?
Measles
– can see leukopenia and thrombocytopenia
Vit A to reduce mortality
- helps immune enhancement
- helps GI and resp epi to regenerate
1 cause otitis media
Treatment?
Strep pneumo (#1)
Then:
Hib
moraxella
Tx w/ amoxicillin x 10d
If tx and doesn’t get better, conclude is HIb or Moraxella and give augment
Acute unilateral lypmhadenitis
Cause?
Most common cause?
Usually bacterial infection
#1 = Staph aureus #2 = Group A strep
Tx = dicloxacillin to cover strep and staph
Prevent neonatal ophthalmic chlamydial infection
ONLY prenatal maternal testing + tx
Erythromycin is only effective for gonococcal conjunctivitis
Infant botulism transmitted by…
Ingesting food contaminated with C botulinum
Germ grows in gut –> makes toxin –> clinical signs
When do pts with genetic B cell deficiency begin to develop recurrent infections?
After 6 mo
No more passive ab from mom
3 most common causes of conjunctivitis in neonates
Chemical (via silver nitrate) - tx supportive management!
Gonococcal
Chlamydial
Gonococcal conjunctivitis (ophthalmia neonatorum)
Present at 2-5 day old
Copious purulent exudates
Eyelid swelling
Eyelid exudates
Dx:
- Gm stain w/ intracellular Gm- diplococci
- Cx on THAYER MARTIN media
Tx:
- IM or IV ceftriaxone or cefotaxime
- hospitalization to assess tx response
Ppx:
- Erythromycin ophthalmic ointment within 1 hr birth
…if untreated –> corneal ulceration, scarring, blindness
Chlamydia vs Gonorrhea conjunctivitis
Chlamydia happens later (5-14 d) vs 2-5 d for gonorrhea
Chalmydia has more chemosis
- less eyelid swelling
- less purulent d/c - it is more mucoid
- blood stained eye discharge is characteristic
Tx:
- oral erythromycin
How do you dx early localized lyme disease?
Based solely on presence of erythema chronicum migrans
Tx lyme disease
Doxycycline
Amoxicillin
Cefuroxime
- Doxy used more b/c can also tx anaplasma phagocytophilum
DO NOT use doxy in kids < 8 yo and preggers
–> Oral amox or cefuroxime for kids < 8 yo and preggers
Disseminated dz –> ceftriaxone or penicillin G
DO NOT use steroids for bells palsy - just use same for erythema migrans
When is it ok to use tetracycline?
> 8 yo kid
What is the incubation period of varicella?
3 weeks
Most pts develop sx within 2 weeks of exposure
How effective is varicella vaccine after exposure?
70-100% 3-5 days of exposure
Not ok for > 5 days after exposure
Potential complications of varicella infection
Children - bacterial superinfection
Adults - pneumonia
Orbital cellulitis features
Pain w/ eye mvmts
Proptosis
Ophthalmoplegia
Diplopia
Most common predisposing factor for orbital cellulitis
Bacterial sinusitis
Use contrast CT to ID abscesses needing surgery
TORCH infections
Toxo CMV Congenital rubella HSV Syphilis
Toxoplasmosis
- risk
- effect on baby
- dx
- tx
- raw meat eating or cat feces
- intracranial calcifications***
- chorioretinits
- hydrocephalus 2/2 aqueductal stenosis
Dx IgM immunosorbent agglutination assay
- -> Tx mom spiramycin for 1st sem, pyrimethamine + sulfonamide afterward
- -> Tx baby pyrimethamine + sulfonamide leucovorin
CMV
- risk
- effect on baby
- dx
- tx
1 congenital infection
- periventricular calcifications*******
- chorioretinitis
- # 1 cause sensorineural hearing loss
- seizures
- IUGR
- hepatosplenomegaly
- microcephaly
Dx culture or PCR
Prognosis poor
Rubella
- risk
- effect on baby
- dx
- tx
If 1st trimester infection –> 80% babies affected
- transmitted via resp droplets
- cataracts*****
- PDA, pulmonary stenosis
- blueberry muffin lesions 2/2 dermal erythropoiesis
- sensorineural hearing loss
Dx IgM titers
Prevent w/ immunizations
HSV
- risk
- effect on baby
- dx
- tx
Usually 2/2 passage through infected canal
Primary dz in mother has high rate of transmission
- Encephalitis
- herpetic (vesicular) lesions
Tx acyclovir
Syphillis
- risk
- effect on baby
- dx
- tx
Transplacental transmission
Often result in stillbirth, hydrops fetalis
Usually asymptomatic
If sx…
Early stage
- appear before 2 yo
- FTT
- maculopapular rash (esp on palms + soles)
- thrombocytopenia
- hepatosplenomegaly
Late stage
- skeletal –> saber shin, hutchinson teeth, saddle nose, clutton joints
Dx:
- VDRL or RPR first
- confirm w/ FTA-ABS
Tx:
- Parenteral PCN G
Causes of neonatal bacterial sepsis + associations
Group B strep & E. coli
- #1 causes of early and late onset sepsis
Staph aureus
- skin, bone, joint infections
Listeria
- early onset sepsis
Enterococcus
- sepsis in preterm
Coag-negative staph
- in intravascular catheters that are indwelling
Other Gm - bacteria (Klebs, Enteriobacter, P. aeruginosa)
- late onset sepsis, esp in infants in ICU
Fever of unknown origin
Lasting > 14 days in child
< 36
> 21 days in adolescent or adult
Fever without a focus
Lasting < 1 week in children < 36 mo old
Occult bacteremia (bacteremia w/o obvious focus) is usually 2/2 to
S pneumo
N meningitidis
H influenzae B
Salmonella
Fever in pts < 3 mo old..should consider what?
Meningitis
UTI
PNA
Tx bacteremia in children
< 1 mo old
- admit
- ppx abx for group B strep, listeria, e coli
Ceftriaxone if:
- look ok
- no source of fever
- WBC > 15,000
Causes of meningitis
< 3 mo old
- Group B strep
- Listeria
- E. coli
> 3 mo
- N. meningitides
- S. pneumo
- H. influenzae B
Sickle cell
- pneumococcal
CSF shunt infection
- Staph epi
Physical signs of meningitis
Bulging fontanelle in infants
+ Brudzinski (involuntary flexion of knees + hips after flexion of neck while supine)
+ Kernig (flexion of hip 90 deg w/ subsequent pain on extension of leg)
When does aseptic meningitis usually happen?
Summer
Fall
Origin usual viral
ppx for family contacts of pts w/ what meningitis causing organisms?
Give rifampin for contacts of:
H. influenza
N. meningitides
What are causes of arboviral encephalitis? Which one has worst prognosis?
St louis encephalitis (birds)
California encephalitis (rodents –> mosquitoes –> baby)
Western equine encephalitis (mosquitoes + birds)
Eastern equine encephalitis (mosquitoes + birds) –> poor prognosis
Colorado tick fever
1 pathogen
Most common days osteo spreads in kids
Acute hematogenous spread
Staph aureus
Associations of osteo…
Sickle cell - Staph aureus, salmonella
Dog or cat bites - pasteurella
puncture wounds of foot through sneaker - pseudomonas
Dx osteo
Periosteal bone culture
Radiographs are only + 10-14 days after showing soft tissue swelling and periosteal elevation
MRI if radiographs neg but strong suspicion
How to determine response to therapy in osteo?
ESR
CRP
Hip pathology refers pain to..
the knee!
Dx septic arthritis
Arthrocentesis
WBC and ESR will be elevated
US good for septic arthritis of hip!
Reading ppd
> =5 mm —> + if exposed to TB or immunocompromised
> =10 mm –> + if high risk (health care, homeless)
> =15 mm —> + if low risk
prior BCG vaccine never contraindication for ppd
Side effects of Tb drugs
INH Rifampin Pyrazinamide Streptomycin Ethambutol Ethionamide
INH
- hepatotoxicity
- neuritis
Rifampin
- hepatotoxicity
- thrombocytopenia
Pyrazinamide
- Hepatotoxicity
Streptomycin
- ototoxicity
- nephrotoxicity
Ethambutol
- ocular toxicity
Ethionamide
- hepatitis
Stages of pertussis infection
Stage 1 - catarrhal
- last 1-2 wks
- rhinorrhea, conj injection, cough
Stage 2 - paroxysmal stage
- 2-4 wks
- coughing spasms, inspiratory whoop, facial petechiae
Stage 3 - convalescent stage
- 1-2 weeks
- dec freq of sx
Dx pertussis
1st 4 weeks:
- Culture from nasopharyngeal secretions** of B. pertussis is gold standard
After 4 wks:
- serology
Tx pertussis
Suppportive
Severe dz –> hospitalize
Erythromycin to shorten period of communicability but does not affect paroxysmal stage
Ppx ALL close contacts w/ erythromycin, even if immunized
Bartonella hensalae
Small red papules at site of inoculation appearing in LINEAR fashion
Chronic regional lymphadenitis
- start enlarging in 1-4 weeks and stay that way for 2 months
Parinaus oculoglandular syndrome happens after rubbing eye with hands after cat contact sometimes happen
- unilateral conjunctivitis
- preauricular lymphadenopathy
- cervical lymphadenopathy
How do you dx Bartonella hensalae?
Usually hx
Warthin Starry stain can see the gram negative bacilli
Tx bartonella hensalae
No tx usually resolves spontaneously
Complications of parvovirus B19
Aplastic crisis, esp if sickle cell +
Fetuses –> can develop fetal hydrops and death
Tx measles
Supporive
Vitamin A
Isolation
Complications w/ measles
Otitis media #1
PNA
Subacute sclerosing panencephalitis (1/1000 get this after measles)
Tx rocky mountain spotted fever
Rickettsia rickettsii
Pale rose-red maculopapular rash
Starts and palms and soels and spreads to entire body
Tetracycline
Doxycycline
–> ok in kids < 8 yo since only 1 dose
Chloramphenicol for tetracycline allergic
Complications of rocky mountain spotted fever
Rickettsial vasculitis causing gangrene fo digits, ear lobes, nose, scrotum, entire limbs
Neuro sequelae
Complications of varicella
2/2 infection w/ group A strep and staph aureus
PNA
Guillain Barre
encephalitis
Cerebellar ataxia
Tx scarlet fever
Penicillin
Erythromycin
Clindamycin
1st gen cephalosporins
Mumps
Viral infection
Painful enlargement of salivary glands (mainly parotid)
- can have erythema and swelling around Stenson’s duct
Dx with hx; serum amylase elevation common
Tx - supportive
Complications
- menigoencephalitis
- orchitis (infertility rare)
- mild pancreatitis
- sensorineural deafness (very common with infection)