Infectious Disease Flashcards
(70 cards)
1
Q
Fever without source
A
fever of one week or less
history, physical, labs don’t show source
2
Q
Fever of Unknown Origin (FUO)
A
Fever for at least 8 days
history, physical, labs don’t show source
3
Q
PNA triad
A
tachypnea + high fever+ cough
4
Q
Rigors
A
sudden feeling of cold, shivering, rise in temp, sweating
-higher probability of SBI
-can indicate serious non-bacterial
-dengue, malaria, chikungunya
5
Q
Localizing signs of SBI in Children
A
- lethargy, irritability, change in mental status
- tachycardia disproportinate to degree of temp elevation
- tachypnea or labored respirations
- bulging or depressed anterior fontanel
- nuchal rigidity
- petechiae
- localized erythema, tenderness, or swelling
- abdominal or flank tenderness
- fever
6
Q
risk factors for occult bacteremia
A
- 36 mts or younger
- > 39.5 C or 103.1F
- WBC ≥ 15,000 or ≤ 5,000
- total band cells ≥1500
- ESR ≥ 30 mm/hr
- underlying chronic disease (malignancy, immunodefeciency, sickle cell, malnutrition)
- clinial appearance (irritability, lethargy, toxic appearance)
7
Q
Diagnostic work up: ≤90 days
A
Fever criteria- 100.4 or higher
CBC w/ diff, cath urine, blood/urine culture, CRP, procalcitonin
if ≤29 days or if concerns- lumbar puncture
stool studies/ culture- if diarrhea
WBC alone not reliable, viral PCR can be helpful but don’t stand alone
chest x ray if respiratory sysmptoms- tachypnea, hypoxia, rales, wheezes, increased WOB
8
Q
Diagnostic work up: 3-36 mts
A
3-24 mts- 102.2 w/o clear source
24-36 mts- 103.1 w/o clear source
- if not at increased risk, at least 2 doses of prevnar PCV12- do not need blood testing
- if at increased risk because unimmunized, unknown vaccine status, or 1 dose prenar- may need screen eval w/ CBC, blood and urine cx
infants w/ temp >102.2
- urine testing- females < 2, uncircumcised < 1 yr, circumcised < 6 mts
infants w/ temp >103.1 & WBC > 20,000- chest x ray to detect occult pna
9
Q
Diagnostic work up: > 36 mts
A
- lab eval dependent on H&P
- work up for chronic disease - sickle cell, cancer, immunodeficiency, nephrotic syndrome, cardiac transplant
- children w/ CP- higher chance of UTI
- chidlren w/ CF- increased risk of respiratory infection
- cognitive impairment- higher chance of LRT d/t decreased ability to clear airway
10
Q
Common organisms for SBI/ Occult Bacteremia- ≤ 3 mts
A
E coli
Group B strep
streptococcus pneumoniae
listeria monocytogenes
salmonella (> 1 mt)
haemophilus influenzae type b (> 1 mt)
11
Q
Common organisms for SBI/ Occult Bacteremia- 3-36 mts
A
s. pneumoniae
neisseria meningitidis
salmonella
staphylococcus aureus
HIB
12
Q
Meningitis
A
Inflammation of the meninges
CSF -elevated protein count, low glucose
13
Q
Meningitis Etiology 2 weeks
A
Group B Strep
E Coli
Enterococcus
Listeria monocytogenes
14
Q
Meningitis Etiology 3-6 wks
A
group b strep
HIB
Streptococcus pneumoniae
Neisseria meningitides
E. coli
Listeria monocytogenes
15
Q
Meningitis Etiology 7 weeks-15 yrs
A
HIB
Streptococcus pneumoniae
Neisseria meningitides
16
Q
Meningitis etiology > 15 yrs
A
Streptococcus pneumoniae
Neisseria meningitides
streptococcus
17
Q
Meningitis clinical signs
A
hyper/hypothermia, jaundice, hepatomegaly, lethargy, poor feeding, vomiting
bulging fontanel in 1/4 - late onset, rarely nuchal rigidity
18
Q
Meningitis - early onset
A
- first 5 days, death rate 20-50%
- acquired at delivery
- typically secondary to septicemia from maternal infection (vertical transfer)
- e coli or GBS
19
Q
Meningitis-late onset
A
- after 5-7 days, death rate 20%
- post natal symptom onset
- e coli, GBS, enterococci, gram negative enteric bacilli (i.e klebsiella), listeria moncytogenes
20
Q
Meningitis treatment- newborn
A
- ampicillin & aminoglycocide (gentamycin) or cefotaxime
- +/- acyclovir
- older than 1 week - vancomycin + gentamycin
- treat for 2 weeks at least beyond sterile CSF (typically 14-21 days)
- sequelae: hydrocephalus, CP, epilepsy, cognitive impairment, deafness
21
Q
Erythema Infectiosum (fifth disease) etiology, transmission, incubation
A
parovirus B19
respiratory route, blood, blood products
incubation 4-28 days
22
Q
Parovirus clinical manifestations
A
- prodromal phase - LGF (15-30%), HA, Mild URI
- Rash (afebrile)- hall mark characteristic
- begins w/ facial flushing (slapped cheek)
- spreads to trunk and extremeties as diffuse macular erythema
- central clearing- lacy, reticulated appearance
- waxes & wanes for 1-3 wks
- can recur w/ exposure to sunlight, heat, exercise, stress
23
Q
Erythema Infectiosum complications
A
- arthropathy - more common in adults and older adolscents after infections, joints most affected are hands, wrists, knees, ankles
- transient aplastic crisis - increased risk for sickle cell pts
- immunocompromised pts at risk for chronic infection- chronic anemia, neutropenia, thrombocytopena, or complete bone marrow suppression, treated w/ IVIG
- primary maternal infection associated w/ fetal hydrops and IUFD
24
Q
Erythema Infectiousum diagnosis/ differentials/ treatment
A
Diagnosis
- typically based on clinical symptoms
- antibody testing available, usually not done in peds
- PCR testing
Differntials
-rubella, measles, enterovirus infections, drug rx
arthralgias- JRA, SLE
Treatment- symptomatic
25
Acute Herpetic Gingivostomatitis s/s
s/s: pain in the mouth, salivation, fetor oris, refusal to eat, fever (up to 104-105F)
fever & irritabiltiy precede oral lesions by 1-2 days
mouth lesions are vesicular, which rupture and are covered by a yellow-gray membrane, which sloughs into ulcer
26
Acute Herpetic Gingivostomatitis treatment
Acyclovir PO 15mg/kg/dose given 5x/day x 7 days
(start w/i 72 hrs of onset)
27
Herpetic Whitlow
HSV infection of minor trauma around the nail
Painful, deep seated spreading lesions w/ vesicles
resolve spontaneously in 2-3 wks
Treat w/ acyclovir PO
28
Herpes Simplex Virus diagnosis
two of the following:
- clinical picture
- isolation of the virus
- development of specific antibodies
- demonstration of characteristic cells, histologic changes, viral antigen or HSV DNA in scarapings, CSF, or biopsy material
29
HSV treatment
dosing dependent on indication
Acyclovir 10-15mg/kg/dose q8hr
30
Varicella- Zoster Disease etiology/transmission
Etiology: varicella-zoster virus (herpesvirus)
Transmission:
airborne or direct contact
contagious 24-48 hrs before rash and until vesicles are crusted
10-21 day incubation period
31
Varicella Rash
Prodrome 24-48 hrs before rash: fever (100-102), malaise, anorexia, headache, mild abdominal pain
Rash begins as **erythematous macule** (flat) → **papules** (raised) → clear, fluid filled **vesicles** (dew drop on a rose petal)
- fluid becomes cloudy, then crusting
- lesions appear in different stages
32
Varicella diagnosis
Diagnosis:
based on clinical presentation
CBC- leukopenia in first 72 hrs → lymphocytosis
PCR & antibody testing available
33
Varicella Zoster treatment
uncomplicated varicella- symptomatic treatment only- treat itchiness, fever, discourage scratching
acyclovir PO 20mg/kg/dose q6hrs x 5 days - should be initiated w/i 24 hrs
acyclovir IV 500 mg/m2 q8hr (for severe disease or immunocompromised)
34
Varicella complications / prevention
complications: bacterial infections, encephalitis, cerebellar ataxia, pna
prevention:
isolation rooms w/ filtered air systems
vaccine- 12 mts, 4-6 yrs
35
Varicella post exposure prophylaxis
Immunocompromised children, pregnant women, and newborns exposed to VZV:
varicella zoster immune globulin (VZIG)
Healthy children:
administer vaccine within 3-5 days of exposure
36
Breakthrough Varicella
- occurs in previously immunized child at least 42 days after vaccination
- rash is more likely to be non vesicular
- typically mild fever w/ less than 50 lesions
- still infectious
37
Progressive Varicella
complication of varicella in immunocompromised children, pregnant women, newborns
visceral organ involvement, coagulopathy, severe hemorrhage, continued lesion development
38
Herpes Zoster
(shingles)
**vesicular lesions clustered** within **dermatomes**
in children, rash is mild, acute neuritis is minimal
in immunocompromised- more likely adult form w/ post herpetic neuralgias
39
Herpes Zoster treatment
Acyclovir PO -if less severe dx
Acyclovir IV (500mg/m2 or 10mg/kg q8hr)- immunocompromised
40
EBV/ Infectious Mononucleosis transmission
caused by epstein barr virus, transmitted in oral secretions
shed in oral secretions for > 6 mts after acute infections, then intermittently throughout life
41
# ```
Infectious Mononucleosis clinical manifestations
- incubation period of 30-50 days- prodrome usually lasts 1-2 weeks
- classic presentation: low grade fever, sore throat, exudate on tonsils, fatigue
- some patients may just have lymph node swelling or fever/chills and fatigue
- splenic enlargement occurs in first few weeks
- epitrochlear lymphadenopathy
- prognosis: major sx last 2-4wks, fatigue may wax and wane
42
Infectious Mononucleosis diagnosis
presence of typical symptoms
confirmed by serology:
- CBC- leukocytosis w/ elevated monocytes and lymphocytes
- heterophile antibody (monostat) -rapid antibody test (detects antibodies in 50% of cases in children < 4)
- EBV titers- IgM peaks early, IgG peaks midway or later in acute phase
43
Infectious mononucleosis treatment
- r/o strep pharyngitis
- rest & symptomatic therapy (APAP/iburpofen for sore throat & HA)
- avoid contact sports and strenuous athletic activities during first 4 weeks or while hepato/splenomegaly present
44
Infectious Mononucleosis complications
(rare)
- splenic rupture- usually during 2nd wk of dx
- airway obsturction- most common cause of hospitilization- IV hydration, humidified air, steroids, consider emergency T&A
(very rare)
- guillain barre syndrome, reye syndrome, hem olytic anemia, aplastic anemia
45
Roseola
(sixth disease or exanthema subitum)
- viral infection caused by human herpesvirus 6 (HHV-6) or HHV-7
- spread through contact w/ infected saliva or through air (cough/sneeze)
- not contagious after 24 hrs of being fever free
46
Roseola clinical picture
prodrome either asymptomatic or w/ mild respiratory symptoms
clinical illness:
- high fever (37.9-40C, 101-106F), irritability, anorexia
- persists for 3-4 days, then fever resolves abruptly
- after fever resolves, rash appears- small pink lesions beginning on the neck and spreads to trunk and extremities, lasts 1-3 days
- resolves spontaneously
47
Roseola rash
after fever resolves → rash appears **small pink lesions** beginning on the **neck** and spreads to **trunk** and **extremities**
lasts 1-3 days, resolves spontaneously
48
Roseola diagnosis/treatment
diagnosis- based on clinical presentatino
treatment- sympotmatic
infections in immunocompromised- can be severe; pneumonitis and encephalitis
49
Influenza clinical manifestations
- Abrupt onset of coryza, conjunctivitis, pharyngitis, and dry cough
- Systemic signs include high fever, myalgia, malaise, headache
- In younger children, illness may isolate to a small area of the respiratory tract (i.e pharynx) and fever may be higher (104-105F)
- Fever typically last 2-4 days and respiratory complaints may persist up to 1 week
Complications- OM & PNA most common
50
Influenza Diagnosis
Usually based on clinical presentation
Diagnostics:
- Rapid influenza testing
- Viral culture
- CBC- leukopenia
- CXR- atelectasis or infiltrate in 10% of children
51
Influenza Treatment
typically sympotmatic
antivirals for young children or severe disease
Oseltamivir (tamiflu)
- infants 3mg/kg/dose BID x 5 days
- fixed dosing for older children
- longer duration for severe illness
52
influenza high risk for complications/ recommended for antiviral therapy
- children < 2yrs
- Chronic diseases: asthma, sickle cell, metabolic disorders (DM), neurologic and deurodeveloment conditions (CP, epilepsy), mod to severe developmental delay, muscular dystrophy, immunosuppresion
53
Measles (Rubeola) clinical manifestations
- **pathognomonic**- Koplik's spot- on buccal mucosa, **erythematous base** with **whitish/grey blue lesion** on top
- Plus: fever, cough, conjunctivities, rash
Complications: tracheitis, PNA, AOM, CNS involvement (rare)
54
Measles treatment
- supportive care for most, isolation
- abx for bacterial superinfection
- hospitilazation for severe dx
- close monitoring & **reporting required**
55
SARS CoV-2 AAP Guidelines
**Asymptomatic or mildly symptomatic **(< 4 day fever, short duration of myalgia, chills, and lethargy)
- No exercise until cleared by physician
- Look for chest pain, SOB out of proportion for URI, palpitations, syncope
**Moderate symptoms** (≥4 day fever, myalgia, chills, lethargy or non ICU hospital stay)
- ECG and cardiology consult
**Severe symptoms **(ICU stay or MIS-C)
- Restricted activity 3-6 mts until cleared by cardio
56
COVID treatment
- Supportive care
- Glucocorticoids (dexamethasone) +/- tocilizumab if required HFNC or higher level respiratory support
- Empiric abx if indicated
- Consider thromboprophylaxis
Consider (severe illness)
- Antiviral therapy - remdesivir, usually 5 days (28 days and older) or Paxlovid
- Janus kinase inhibitor- baricitinib
- Monoclonal antibody therapy- bamlanivimab-etesevimab (< 2 yrs)
Hydroxychloroquine not recommended
56
Post Acute Sequelae of COVID (PASC/ Long COVID)
- Defined as the presence of **one or more new, persistent physical symptoms**, which may **fluctuate and relapse**, that lasts at least **12 weeks** after confirmed initial SARS-CoV-2 infection and** impairs daily function**
57
HIV
selectively infects and destorys CD 4 T lymphocytes
CD4 T lymphocytes stimulate production of other immune cells to fight infection, results in immunodeficiency
57
HIV - Mother to Child Transmission (MTCT)
- intrauterine
- intrapartum
- postnatal (breastfeeding)
How to prevent:
- test pregnant women
- treat HIV infected women w/ ARV drugs during pregnancy and at delivery
- electice c-section
- no breastfeeding
- treat infant w/ ARV drugs after delivery
58
Antiretroviral Prophylaxis
Zidovudine 2mg/kg/dose q6hr or 4mg/kg/dose q12hr
Monitor: CBC (causes bone marrow suppresion- anemia, neutropenia)
59
Clinical presentations that warrant HIV testing
- PCP pneumonia
- Recurrent, severe, and/or persistent oral thrush
- Recurrent bacterial infections
PNA
Sinusitis
OM
- Failure to thrive or poor growth
- Recurrent parotitis (inflammation of parotid gland), lymphadenopathy, chronic interstitial lung disease (Lymphocytic interstitial pna /LIP)
- TB infection
- Shingles during childhood
- Flu like or mono like symptoms, and not improving
60
HIV testing in infancy
< 18 mts - virologic assay- HIV RNA or DNA nucleic acid tests (NAT)
(not HIV antibody test
p24/IgM/IgG sensitive
HIV 1/2 antigen/antibody combination immunoassay
61
Immunosuppression
**< 12 mts**: ≥ 1500 (normal), < 750 severe
**1- < 6:** ≥ 1000 (normal), <500 severe
**≥ 6 yrs:** ≥ 500 (normal), <200 severe**
No live vaccines if severe immunosuppression
PCP prophlaxis for >1 w/ severe immunosuppression, all <12mts
62
Lyme Disease etiology
Borrelia burgdorferi - spirochete found in deer ticks
63
Lyme stages
**Early localized stage (7-14 days after bite)**
- flu like symptoms and erythema migrans (asymptomatic, flat, erythematous patchy w/ peripheral expansion, central clearing)
- lymphadenopathy
**Early disseminated stage (3-5 wks after bite)**
- multiple EM, intermittent arthralgias, peripheral neuropathies (facial nerve)
**Late stage (wks-mts after bite)**
- arthritis & neruological disease
Possible symptoms: HA, hearing loss, paralysis of face, muscle soreness, fever, chills, fatigue, heart complications, N/V
64
Lyme diagnosis/treatment
Diagnosis- lyme titer
Treatment:
- remove tick
< 8 yrs:
amoxiciilin 50mg/kg.day TID x 21 days
cefuroxime 30 mg/kg/day BID
> 8 yrs
doxycycline 4mg/kg/day BID
Prevention: DEET, early removal of tick
65
Rocky Mountain Spotted Fever etiology
rickettsia rickettsii (dog & wood ticks)
66
Rocky mountain spotted fever clinical manifestations
Prodrome:
- H/A (prominent feature, many be severe)
- GI symptoms, malaise, myalgias
Fever, rash, headache (classic triad)
- rash on day 3-5
- peripheral erythematous blanching macules and papules spread centrally. evolves into petechiae and purpura
67
RMSF lab findings
Titers
CBC:
- left shift ( (increased immature neutrophils, indicates inflammatory process or infection) w/ low to normal WBC
- thrombocytopenia
LFT abnormalities
68
