Serious Childhood Infections Flashcards
Cellulitis: Infection with normal skin microflora: resident microflora, __ __ and __ ___ GAS
Infection with normal skin microflora: resident microflora, staphylococcus aureus and streptococcus pyogenes GAS
is eysipelas a deeper soft tissue infection or superficial cutaneous?
soft tissue infection
Superficial Cutaneous bacterial Infections: cellulitis, folliculitis, furuncles/carbuncles, impetigo
Soft Tissue infection: erysipelas, cellulitis, erysipeloid, necrotizing soft tissue infection
is folliculitis a superficial cutaneous infection or deeper soft tissue?
superfiial cutaneous
risk factors for MRSA
Risk factors for MRSA:
Immature immune system/young age
Participating in contact sports
Sharing towels
Immunodeficiency
Living in crowded or unsanitary conditions
Association with HCW
Aboriginal
treatment for cellulitis? MRSA?
Treatment: Cloxacillin/PenG, first generation cephalosporin/cephlex
clindamycin/erythromycin (severe Penicillin allergy)
MRSA: Vancomycin/septra/clindamycin/linezolid
Parenteral therapy if: rapid progression, lymphangitis, lymphadenitis
is nec fasc superficial or deep?
deep seated infection of subcutenaous tissue. can even involve hte muscle.
key virus that increases the risk of nec fasc
VARICELLA
Risk Factors: major risk factor for children <10 years: VARICELLA→ 39 fold increased risk within 2 weeks of the illness
6-16% of invasive GAS infections in children associated with varicella
Initial signs non-specifi
key symptom of nec fasc
severe localized pain out of proportion to the appearance of the lesion
treatment for nec fasc
Treatment: surgical treatment, cefazolin + vanco + clindamycin
+/- IVIG?
which gender is more affected by osteomyelitis?
2x in girls
most common bug for osteomyelitis
s.aureus
Key Organisms: staphylococcus aureus, group B strep, S. Aureus.
MRSA: when it causes osteomyelitis, it is more often multifocal, with bone abscesses, with myositis and other vascular complications.
Severe life-threatening infections more common than MSSA infections.
Duration of therapy is longer
3 main routes of spread that can cause osteomyelitis
Pathophysiology:
- Hematogenous: bacteremia (bacteria in blood) leads to seeding of bone, usually acute
- Can be asymptomatic or symptomatic, where the organism goes to metaphyseal capillary loops and adhere to cartilaginous matrix
- S.aureus expresses bacterial adhesion factor that promote attachment
- Penetrating injury; less common in children. Often because of trauma or surgery
- Contiguous spread: less common in children, from adjacent soft tissue or space infection (chronic otitis media, sinusitis, diabetic foot infection), often chronic, may be more difficult to treat
treatment for osteomyelitis
Biopsy + culture Empiric IV Abx cloxacillin or 1st gen cephalosporin (follow with CRP)–> may be able to move from IV to oral
Treatment: Surgery→ drainage of abscess from proximal left humerus, and adjacent soft tissue. Drainage of cloudy fluid from left knee. May need debridement.
most sensitive investigation for acute osteomyelitis. how?
Investigations:
CBC; Hb, plt, and wbc
ESR
Cultures (blood, urine, CSF, bony aspirate and joint aspirate),
X ray
MRI→ most sensitive investigation for acute osteomyelitis. Detects edema of bone marrow, and adjacent soft tissue abnormalities.
Very useful for infections in the pelvis, spine and skull base.
differentiate between acute vs chronic osteomyelitis. what specific abscess is assocaited with chronic OM?
Acute osteomyelitis: symptoms <2wks (up to 4 weeks)
Chronic osteomyelitis: symptoms >4 weeks where avascular bone (sequestrum) alone or surrounded by new bone (involucrum) present (Brodie’s abscess)
treatment of osteomyelitis
Joint pain, limp in child, long bones, pain out of proportion
note:
DDx for Fever, Pain and Tenderness of Extremity
- Septicemia
- Septic arthritis
- Cellulitis, necrotizing fasciitis
- Bone neoplastic lesions
- Leukemia
- Bone infarction with Sickle Cell Disease or Gauchers
- Toxic Synovitis
Key Viral illnesses that cause septic arthritis
VZV, EBV, parvovirus, Mumps, measles, enteroviruses
Key bacterial joint infections dependent on age
0-3 mos: S.aureus, GBS, GNB
>3 mos: S.Aureus*, K.kingage, GABHS, strep pneumo, H.influenzae
>5 years: S.aureus*
Neisseria, salmonella and GNB in immunocompromised state.
which bacteria (in addition to staph A. can cause septic arthritis in kids with immunocompromisation)?
Neisseria, salmonella and GNB in immunocompromised state.
most affected joints of SA
knee most common, then hip, ankle, elbow
diagnosis of septic arthritis
key symptoms: Red hot joint. swelling, pain, warmth, inflammation
Investigations: CBC, CRP, blood culture, analysis joint fluid, PCR, radiographs, U/S, MRI
Radiology: capsular swelling (ex/ lateral upward displacement of the femoral head)
Diagnosis: • Joint Aspirate: 50-60% +ve • Improved with molecular testing of joint fluid • Blood Culture: 40% +ve
Treatment for septic arthritis
Treatment: diagnosis is key– empiric treatment same as osteomyelitis. Surgical debridement and drainage is key→ repeat needle aspiration may be sufficient and has been shown to have better outcome in adult patients
Key is to remove inflammatory material to minimize joint destruction
Septic arthritis of hip require prompt surgical drainage and irrigation of joint space
Initially abx therapy will by parenteral/IV ceftriaxone for sexually active teen, cloxacillin/cefotaxime +/- vancomycin, then substitute with oral after adequate control of infection/inflammation → ensure compliance
Possible complications: hip dislocation, avascular necrosis of the femoral head, leg length discrepancy
Neonatal Meningitis
Accounts for 20% of neonatal sepsis
Three fold higher in Low Birth Weight infants and premature infants
risk factors for neonatal meningitis?
Risk factors: PROM, chorioamnionitis, premature delivery
key clinical features, microbiology and treatment for NEONATAL meningitis
Microbiology: group B streptococci, gram negative enteric pathogens (Neisseria), listeria monocytogenes, other.
Key clinical features: temperature instability, feeding intolerance, apnea, bradycardia, poor color, slow capillary filling
- Jaundice, lethargy or irritability, high pitched cry, bulging fontanelle, seizures, hypotension
Treatment for NEONATE meningitis: ampicillin (covers listeria) AND GENTAMICIN
If older than 7 days: ampicillin, cefotaxime, gentamicin, and ceftazidime.
T/f dexamethasone in indicated for neonatal meningitis
false. but you should use it for pediatric meningitis >3 montsh
key organisms for pediatric meningitis
Microbiology: haemophilus influenzae type B, streptococcus pneumonia, neisseria meningitidis
key physical exam findings for pediatric meningitis
Brudskis sign, Kernig sign, stiff neck, pupura, focal neuological deficits.
key test to do if you suspect meningitis
lumbar puncture. CSF needs to be collected before antibiotics are started
management of pediatric meningitis
Management; urgent administration of antibiotic parenterally. 3rd Gen Cephalosporin + vancomycin + dexamethasone (must be given before Abx) +dexamethasone
Prevention: chemoprophylaxis for close contacts of patients with HiB/Neisseria, active immunization
Encephalitis in Children
Definition: inflammation of the brain _. Fever, headache and __ in __.
Etiology: caused by any bacteria or virus.
Virus: ____
- • Bloodstream – penetrate blood – brain barrier→ EV / HPeV / Arboviruses
- • Intraneuronal route→ HSV-1 / HSV-2 / Rabies
Clinical Manifestation: __ __ of __, __/__/__ cognition, behavioural changes, speech disturbances, hemiparesis, cranial neuropathies
Diagnosis:
Major criteria: __ __ __→ altered level of consciousness, lethargy or personality change lasting >__ hours with no identifiable alternative cause
Minor criteria (need __):
Documented fever within __ hours
Generalized or partial __
New onset of __ __ findings
CSF WBC count >__Neuroimaging suggestive of __
__ abnormality that is consistent with encephalitis and not attributable to another cause
Encephalitis in Children
Definition: inflammation of the brain parenchyma. Fever, headache and alteration in consciousness.
Etiology: caused by any bacteria or virus.
Virus: EV, HPeV, HSV-1, Arbo, Rabies
- • Bloodstream – penetrate blood – brain barrier→ EV / HPeV / Arboviruses
- • Intraneuronal route→ HSV-1 / HSV-2 / Rabies
Clinical Manifestation: altered level of consciousness, fever/seizures/impaired cognition, behavioural changes, speech disturbances, hemiparesis, cranial neuropathies
Diagnosis:
Major criteria: altered mental status→ altered level of consciousness, lethargy or personality change lasting >23 hours with no identifiable alternative cause
Minor criteria (need two):
Documented fever within 72 hours
Generalized or partial seizures
New onset of focal neurological findings
CSF WBC count >5
Neuroimaging suggestive of encephalitis
EEG abnormality that is consistent with encephalitis and not attributable to another cause
treatment of viral encephalitis
acyclovir + steroids
