Febrile Illness in Children and Pediatric Infectious Disease Flashcards
One of the m/c symptoms in pediatric illness
fever
definition of hypothermia and fever?
- core temperature < 36.5° C (97.7° F)
- core body (rectal) temperature ≥ 38.0° C (100.4° F)
T/F: Young children tend to have higher core temps than adults
T
Fever is a regulated elevation of body temperature mediated by what part of the brain?
the anterior hypothalamus
An insult, MC ____ in kids, induces macrophages to release ____ that function as endogenous pyrogens (fever producing substance)
- viral
- cytokines (IL-1 and 6)
stimulates the production of prostaglandins by the hypothalamus; prostaglandins readjust and elevate the temperature set point
Cytokines
why do we get chills when we have a fever?
- core temp < thermostat setting = feels chilled
- Chills = generate more internal heat - shivering, vasocontricting skin and turnin goff sweat glands
how can fevers be good?
- disrupts growth and reproduction of many invasive pathogenic microorganisms, both bacterial and viral
- lower amount of iron available to invading bacteria, which have a higher iron requirement
- enhances neutrophil migration, T-Cell proliferation, and interferon activity
ways to measure temperature and which is most accurate?
- Rectal (most accurate) - birth to 3 years
- Oral: >4 yrs
- 0.5-1 ⁰F < rectal d/t mouth breathing, recent ingestions of cold liquids - Axillary - 0.5-1 ⁰F < oral
- Fever if the axillary temp 99.0F or 37.2 C - Forehead - Temporal arteries
- MC way due to being quick and requiring little patient cooperation
- Can have false readings if not positioned properly or the external ear canal is occluded by wax
- Not reliable < 6m
tympanic
s/s fever
- Young children desire close contact with warm person
- Wish to be covered by a blanket
- Somewhat lethargic
- dec ability to concentrate
- Irritability and anorexia (esp small infant)
- Hypermetabolic state with flushed cheeks
- Hot and dry feeling of skin
- Dry mouth and lips (dehydration)
- Sweating
- Febrile seizure
- Unusual glitter in eyes
- Sleepy
- Some exceptionally alert and excited (MC kids 5-10y)
- 10-15 beat pulse increase with every 1◦C
what type of fever patient may be safely sent home with symptomatic treatment and careful return precautions
A well-appearing, well-hydrated child with evidence of a routine viral infection
causes of fever
- MC rsp and GI tracts infections - MC viral (rsv, influenza, croup, adenovirus)
- Other sources: autoimmune disease, Neoplastic, Metabolic disease (hyperthyroidism)
supportive measures for fever
- Educate parents
-
MC reason to treat fever is if child is uncomfortable
- Decision to tx is based on child’s behavior, not on any particular threshold
- Some tolerate fevers w/o ill effect, while some become irritable and cranky - Acetaminophen and NSAIDS
- NSAIDS: >6 months, short term safe if >3 months
- Tylenol: >3 months - No aspirin
- Physical cooling
febrile kids are still contagious until when?
fever free for 24 hours
when to seek immediate help with fever
- < 3 months of age
- Fever > 40.6◦C / 105.8◦F
- crying inconsolably or whimpering
- crying when moved or even touched
- difficult to awaken
- Stiff neck
- Purple spots or dots on skin
- breathing is difficult and not better after nasal passages are cleared
- drooling saliva and is unable to swallow
- convulsion
- acts or looks “very sick”
when to seek help within 24 hrs for fever?
- 3-6 months old (unless fever occurs within 48h after a dtap vaccine with no other serious sx)
- Fever > 40◦C / 104◦F
- Burning or pain occurs with urination
- Returned fever afterit has subsided for >24h
- Fever present > 72 h
A ____ infection usually disseminates faster in a younger child
bacterial
Children between ______ of age have been of special interest to researchers and clinicians because fever is most common in this group
they may be difficult to assess, particularly during the first ___ months of age
- birth and 36 months
- 6
When evaluating the febrile young infant, the goal is to ?
identify infants who are at high risk for invasive bacterial infection (IBI) or serious viral infection who therefore require empiric antimicrobial treatment and hospitalization
types of IBIs
UTI, bacteremia, meningitis, pneumonias, skin/soft tissue infections, septic arthritis, osteomyelitis, bacterial gastroenteritis
MCC of most bacterial infections in infants under 90 d
UTI
Risk Factors for IBI/Serious Viral infections:
- < 28 d old
- Ill appearance: lethargy, listlessness, or toxic appearance, rsp distress, petechiae/purpura, inconsolability
- Rectal Temp >104F
- Not immunized (esp first dose of Hib and pneumococcal)
- Prematurity
- Comorbidities
- abx in last 3-7 d
- Risk of maternally transmitted diseases (maternal fever, PROM, cx (+) GBS, genital herpes)
Treatment plans differ on age of child?
what is the one exception?
- Birth - 21 d
- 22-28 d , 29-60 d, 61-90 d.
- 90 d - 36 mo
exception: all ill-appearing children with toxic look will undergo full evaluation
should mothers continue to breastfeed for febrile children?
yes
encourage and provide lactation support including access to breast pumps for nursing mothers
DC parenteral antimicrobial agents and DC hospitalized patients when all of the following criteria are met:
- Negative Cx results x 24-36 h or only positive for contaminants
- appears well or is improving
- No other reasons for hospitalization
labs to obtain for 22-28 d old febrile infants?
- procalcitonin
- ANC/CRP
admit all febrile infants if they are ages ?
8-21 days old
for infants 61-90 days old, a full septic work-up is warranted when?
- Ill, toxic appearing
- Signs of a focal infection (cellulitis, abscess, osteomyelitis, pneumonia) AND
- Abnml WBC count
- inc inflammatory markers (CRP, procalcitonin)
- abnml U/A
febrile infants 61-90 days do not have to have full work up if they meet this criteria:
- Well-appearing with no bacterial focus of infection
- Or a recognizable viral infection (bronchiolitis or rhinovirus)
- Can get U/A and culture (at this age, concurrent UTI is common)
- Can f/u outpatient
The approach to a child who has a fever w/o a source is greatly determined by ?
3 months to 36 months
immunization status
s/s of fever in 3-36 mo infant
- Lesions in oropharynx that can help with viral illness (ulcers or vesicles in gingivostomatitis and hand, foot, mouth)
- Inc work of breathing, nasal flaring, accessory muscle breathing
- O2 <= to 95%
- Abd tenderness, skin findings such as viral exanthems, petechiae
for a 3-36 mo febrile infant who is well-appearing and has incomplete immunization, what w/u and tx?
- CBC
- Blood Cx if WBC is >= 15k
- UA and CX girls < 24 mo, boys uncircumcised < 12 mo, and circumcised < 6 mo
- CXR if WBC count >= 20k
- If WBC >= 15k - Ceftriaxone / Clindamycin
- outpatient f/u 24 hours, if unable, admit
f/u for febrile 3-36 mo old with complete immunization
- An otherwise healthy child who is completely immunized and remains on schedule, routine lab work is not clinically effective and not recommended
- f/u in 24-48 hours if pt remains febrile
what is a simple febrile seizure?
A generalized tonic or tonic-clonic seizure, usually lasting < 15 min and occurring once within 24 hrs of the onset of fever, may begin w/o warning
MCC of febrile seizures
viral infections
At risk 6 months-5 years.
w/u for febrile seizures
- MC benign; can be first indication of meningitis or encephalitis
- must r/o CNS infection
- CMP, CBC, blood culture
- LP if child < 6 mo - Prophylactic anticonvulsants not recommended
- > 1 febrile seizure < 24 h = complex febrile seizure
daily temp greater than 38.3◦C or 101◦F, lasting for at least 8 days, in whom no diagnosis is apparent after initial outpatient or hospital evaluation that includes careful H&P and initial lab test
Fever of Unknown Origin (FUO)
3 MC causes of FUO
- infectious diseases
- connective tissue/rheumatologic diseases
- neoplasms
- Other: drug fever, factitious fever, CNS dysfunction, and others that do not fit into above categories
6 MC infectious causes of FUO
CMV, EBV, osteomyelitis, hepatitis, adenovirus, enteroviruses, and bartonellosis (cat-scratch disease)
MC autoimmune cause of FUO
systemic idiopathic juvenile arthritis
MC malignant causes of FUO
leukemia, lymphoma
w/u for FUO
- CBC with peripheral smear
- CMP
- ESR, CRP
- Blood cx
- UA and cx
- NP Viral Swab
- Chest radiographs
- specific serological tests for Hep A and B, EBV, toxoplasmosis, bartonellosis, and CMV
- Certain radiograph studies, bone marrow exams, and ct exams may be indicated
disposition for FUO
- Return if new complaints arise or change in clinical status
- If FUO persists and child is well appearing: subsequent eval and order labs only as necessary (new sx arise)
- If ill with persistent F and no dx: get IgG, IgA, IgM
- Imaging of GI tract, US, CT
interventions for FUO
- DC nonessential medications
- NSAIDS
- AVOID empiric abx therapy except those where a life-threatening condition is suspected
- Can interfere with isolation of an organism from cx - refer if persistent F and ill-appearance with no dx after initial eval; ID, rheum, or hem-onc
MCC of bacterial sepsis in newborn?
- group B β-hemolytic strep (GBS)
- gram-negative enteric pathogens (MC E. Coli)
- Listeria; Staph. Aureus
bacterial sepsis MC affects at what age?
- Most commonly occur on day 1 of life
- Majority < 12 hours old
RF for bacterial sepsis in newborn
- Chorioamnionitis, Maternal GBS bacteriuria in current pregnancy.
- Intrapartum maternal temperature of 100.4F or higher
- Maternal GBS colonization
- Membrane rupture greater than 18 hours
- Prematurity
- Additional in premature children: Low circulating IgG, Nosocomial infections d/t premature epithelial barrier, Other invasive devices
s/s of early bacterial sepsis
- Early onset, mostly GBS and e. coli
- Rsp distress d/t pneumonia is MC presenting sign
- Unexplained low Apgar scores w/o fetal distress
- Poor perfusion
- HoTN
- Low WBC, NEUT, hypoglycemia, hyperglycemia, and or unexplained metabolic acidosis
s/s of late onset bacterial sepsis
- s. aureus
- Presents in a more subtle manner
- Poor feeding
- Lethargy
- Hypotonia, temperature instability, low perfusion
- Inc oxygen requirements
- Apnea
- MC associated with bacterial meningitis
- Similar lab values as early onset
- CBC
- Blood cultures
- CSF
- Pleural fluid from effusion (diagnosis of pneumonia)
- CXR
- Any preterm infant with rsp disease requires blood cx and broad-spectrum abx
tx for preterm infants for bacterial sepsis
Blood cx and broad-spectrum abx x 48-72 hrs pending results
- Early: Ampicillin + gentamicin/cefotaxime
- Late - same, but add Vanc
prevention of bacterial sepsis
- PCN 4 hrs prior to delivery
- vaginal and rectal GBS cx at 35-37 wk
- Prophylatic PCN if GBS (+) or unknown GBS status at delivery
what virus causes over 80% aseptic meningitis
non-polio enteroviruses
- Onset acute
- MC < 1 y/o
- Marked F, irritability, and lethargy
- Abd pain, V/D
- Maculopapular rash, w/ some petechial rash
- Full anterior fontanelle
- Older children - frontal HA, photophobia, and myalgia; abd pain, N/V/D; Meningeal signs; flaccid paralysis possible
viral meningitis
w/u findings of viral meningitis
- Early: PMN cells, then MN cells 8-36 hours
- protein < 80mg/dl, and glucose >60% of serum values; mild subtle changes in CSF
- Dx: PCR for enteroviruses
tx for viral meningitis
- No specific tx therapy; supportives
- Infants usually hospitalized, isolated, and treated with fluids and antipyretics - make sure their fever is under control!!
- Can give prophylactic abx until a negative cx is received
- If older child, can withhold abx and observe
what vaccine is responsible for a decrease in bacterial meningitis incidence?
pneumocccal
Can be recurrent; can complicate serious head trauma
s/s of bacterial meningitis
- Abrupt F, often with chills
- Irritability, convulsions, neck stiffness
- most important sign in very young infants: tense, bulging, fontanelle
- older children: fever and chills, HA and vomiting
- Classic signs: nuchal rigidity + brudzinski and Kernig signs
w/u for bacterial meningitis
- Pronounced leukocytosis
- 80-90% PMNs
- CSF inc wbc count and protein, dec glucose
- G+ diplococci may be seen on some stained smears of CSF sediment
tx for bacteria meningitis
- IV Vancomycin + Cefotaxime/Ceftriaxone until bacteriological confirmation
- +/- steroids
- If isolate is PCN susceptible: IV Penicillin G, or ceftriaxone if cephalosporin susceptible
- Meningitis MC form of this bacteria
- Highest attack rate is within the first year of life
- Also elevated again in teen years
tx too?
Neisseria Meningitidis
tx: rifampin