infection Flashcards
wright stain
WBC
wright stain
WBC
fluorecent ab staining
herpes, VZV, repsatory virus like RSV, adenovirus, influenza
most likely viral. nonspecific sx- fever, decr appetite, irritability, cough, rhinorrhea, v, d, apnea
hospitalize if
bacteria by age
0-1mo: GBS, ecoli, listeria=amp/Gent or cef
1-3: GBS, strep pneumoniae, listero: amp/cef/vanc if bacteiral meningitis suspected
3mo-3y: strep pn, influencae type b, neisseria meningitis- cef+vanc if meningitis
>3yo; strep p, neisseria mengitis-cef+vanc if meningitis
low risk of bacterial infection in
if appear well, no focal site of infection. WBC: >5,
fluorecent ab staiining
herpes, VZV, repsatory virus like RSV, adenovirus, influenza
bacterial meningitis
highest incident in 1st mo. RF- ventriculoperioneal shunt, basilar skull fracture
sx- may have fever, bulging fontanelle
older- alt lcl of consciousness, nuchal rigidity, pos kerning and brudzinski sign, seizure, photophobia, emesis, HA
dx- LP, blood culture, CT w contrast for abscess
complications- most in gram neg, then s pneumonia, HIB, Neisseria meningitis. hearing loss most common-25% pt, global brain injury 5%, SIADH, seizure, hydrocephalus, brain abscess, CN palsy, learning disability
bacteria by age
0-1mo: GBS, ecoli, listeria=amp/Gent or cef
1-3: GBS, strep pneumoniae, listero: amp/cef/vanc if bacteiral meningitis suspected
3mo-3y: strep pn, influencae type b, neisseria meningitis- cef+vanc if meningitis
>3yo; strep p, neisseria mengitis-cef+vanc if meningitis
low risk of bacterial infection in
if appear well, no focal site of infection. WBC: >5,
btw 3-36mo fever
pneumoniae most common.
if toxic-need hospitalization, IV antibiotics, eval for sepsis
102.2 -urine culture, blood culture if wbc>15, cxr if RD, stool culture if blood or mucus or >5 WBC on wright test, empire antibody for abc >15
fever of unknown origin
fever 8d-3wk with no dx. most is unusual presentation of common infection. 25% spontaneously resolve w/o dx. causes by common-infection, rheumatoloic d, malig (lymphoma, leukemia),
meningitis
highest incident in 1st mo. RF- ventriculoperioneal shunt, basilar skull fracture
sx- may have fever, bulging fontanelle
older- alt lcl of consciousness, nuchal rigidity, pos kerning and brudzinski sign, seizure, photophobia, emesis, HA
LP for meningitis
look for pleohypoglycorrhachia, incr protein, pos gram stain and culture, cytosis with prelim neutrophil, WBC>5K,
bacteria- PMN predoc, high protein, low flu, pos gram stain
viral- PMN early then mono and lymph (HSV-RBC), normal to high protein, normal flu, ~culture/PCR
TB: lymph predoc, very high protein, low flu, AFB smear rarely pos, PCR pos
fungal- lymph predoc, normal to high protein, low flu, culture pos, india ink for cryptococcus
parameningeal focus- poly or monos prelim, high protein, normal flu, neg culture
bacterial meningitis tx
antiobiotics. corticosteroid bf 1st dose decr hearing loss, supportive care- monitor for SIADH
aseptic miningitis
inflm of meninges with CSF lymphocytic pleocytosis. if viral, normal CSF flu, min elevated protein.
if TB- in 2nd wk become CN palsy, alter consciousness, coma, paraplegia, death
can be bacterial- tb, lyme, syphilus
simple URI (common cold)
present, low grade fever, rhinorrhea, cough, sore throat, resolve 7-10d
tx- hydrate. dd otitis, sinusitis
sinusitis
acute: pneumonia, influence, catarrhalis, amoxilin, or 2nd ten cephalosporin 10-14d
subacute: same as acute but 30-90d
chronic: >90d, CF, allergy, immune def, s aureus, anaerobes, trial of broad spectrum oral antibiotics, CT image sinuses, IV antibiotics
. no imaging, dx base on clinical press
pharyngitis
viral- same as common URI-cox, EBV, CMV
bacteria- strep pyrogenes = GAS= common pediatric infection (self limiting usually but tx to prevent serious complication ~ rheumatic fever), diptheria, GABHS
sx btw viral and bacterial overlap
EBV pharyngitis
may have enlarged posterior cervial LN, malaise, hepatosplenomegaly
corticosteroids
coxsackievirus
painful vesicles or ulcer on posteiror pharynx and soft palate- herpanginia, hand foot mouth disease- blisters
GABHS
lack other URI sx, exudate on tonsils, petechiae on soft palate, strawberry tongue, enlarged tender anterior cervical LN, fever, scarlatiniform rash
need oral penicillin, IM penicillin, or erythromycin or macrocodes
GAS
if suspect, do rapid strep test to detect strep ag from throat swap. if neg, do throat culture
starting antibiotics w/in 9d of acute illness prevents rheumatic fever.
oral amoxicillin. IM for child who refuse PO.
systemic onset juvenile idiopathic arthritis (JIA)
a rheumatic disease
subdiv: oligoarthritis, polyarthritis, or systemic onset disease (still’s disease)
P: Prolonged fever could suggest Still’s disease
Rash
Arthritis (although active arthritis in Still’s disease often presents months to years after onset)
Visceral involvement (e.g., hepatosplenomegaly, lymphadenitis, serositis)
kawasaki disease
vasculitis.
to Dx need
1) fever>5d.
2)nonpurulent conjectivitis.
3) mucosal changes o oropharynx (strawberry tong, red cracked(fissured) lips)
4) maculopapular rash
5) swelling and erythema of extremities
6) lymphadenopathy (cervical, unilateral)
labs: predom neutrophils, normochromic, normocytic anemia, MCV normal, elevated plt, elevated LFT, ERS/CRP incr (sensitive, not specific), sterile pyuria with WBC
need to evaluate all for coronary artery aneurysm so get echo then f/u echo in 1-2wk
other complication: CNS manifestation, liver dysfunc, arthritis, hydrous of GB. Cause inflm = vasculitis -can cause acute coronary artery dilation and aneurysm formation- can be screened for using echo in kids. incidence of aneurysm decr if tx w/in 7d of sx
Tx: aspirin (6-8wks) + IVIG (can decr aneurysm)
osteomyelitis/ septic J
bacteria. 80% LE.
P: low grade fever, painful walking
Rocky mountain spotted fever (RMSF)
tick borne bacterial infection (rickettsia rickettsii). SE america
Fever
Headache
Rash (typically starts on ankles and wrists and progresses centrally and to palms and soles*; may be maculopapular at first, quickly becoming petechial; in 5% of cases, there may be no rash)
Myalgias
hepatosplenomegaly and jaundice
CNS- HA, sx
hypotension
Labs: thrombocytopenia, incr LFT, hyponatremia. aspectiv meningitis
dx- clinical.
management- oral doxy + supportive care
palm and sole rash dd
kawasaki, enterovirus, RMSF, syphilis
scarlet fever
GAS. fever
steven johnson syndrome
mucocutaneous D cause by HS to med, infection, other illness. severe pruritic rash (erythema multiform) fever
enterovirus
fever 3-5d.
non descript, non painful rash
b/l lymphadenopathy
meningococcemia
neisseria meningitis. acute onset of fever, chills, malaise, prostration
rash- urticarial, maculopapular or petechial- prplish, hemorrhagic spots. fulminant- prpuric + large hemorrhage into skin.
immunization prevent infection
roseola
This macular or maculopapular rash, also called exanthem subitum, starts on the trunk and spreads to the arms and neck.
There is usually less involvement of the face and legs.
The rash is preceded by three or four days of high fevers, which end as the rash appears.
Usually seen in children less than two years old.
VZV
erythematous macule to papule to vesicle to pustule then crust over. mild fever. week
generalized lymphadenopathy 2/2 infection
measles (+ splenomegaly), CMV, EBV, HIV, histoplasmosis, toxo, mycobacteria (also localized)
generalized lymphadenopathy 2/2 non infectious
lymphoma, leukemia, histiocytosis, metastic neurblastoma, rhabdomyosarcoma
cervical lymphadenopathy
bacterial cervical adenitis, cat scratch disease, mycobacterial infection,
bacterial cervical adenitis
1-5yo +hx of URI
S. aureus, Strep pyrogenes.
high fever+ toxic
overlying cellulitis and fluctuant on lymphadenopathy
cat scratch disease
bartonella henselae. asx or sx.
self limited in 4-6wk
regional lymphadenopathy. papule first. fever in 1/3. uncommon- paranoid oculoglandular syndrome (conjunctivitis, pre auricular lymphadenitis)
dx: elevated IgM to B henselae
tx: supportive. antibiotics if systemic sx (azythromycin, TMP/SMX)
mycobacterial infection v lymphadenopathy
12yo- lymphadenitis is most common P of TB
erythematous then violaceous as nodes enlarge- may rupture and drain through sinus tract
tx- surgical excision. no I&D bc make sinus tract
strawberry tongue
GAS, kawasaki, toxic shock syndrome
reye syndrome
long term aspirin in children + influenza virus A or B cause multi organ damage. so bf start aspirin tx (kawasaki), vaccinate.
AMS dd
hypoxia, hypoglycemia, poisoning
acidosis/shock: intussucpetion, sepsis, DKA, renal failure
encephalitis
AMS and fever but no tachypnea.
tachycardia
1st sign of inadequate perfusion.
acute otitis media (AOM)
acute infection of middle ear space.
agents: bacteria- s pneumoniae, non typeable H influenze and moraxella catarrhalis. virus of simple URI= why often dev during or after URI..
sx- fever, ear pain, decr hearing
if tympanic me perforates, see pus or fluid drain from ear
dx- ID fluid in middle ear space with sx of infection. pneumatic otoscope see abn mV of tympanic me = best . erythema and loss of TM landmarks-unreliable
tx: antibiotics-amoxicillin
otitis media with effusion (OME)
fluid w/i middle ear space wo sx of infection
otitis externa
infection of external auditory canal (EAC)
patho: cerumen removal, trauma, maceration of skin from swimming, excessive moisture or humidity
etio- p. aeruginosa, s. aureas, gandida albicans. can dev 2/2 AOM
cP: pain, itching, drainage from ear. no systemic sc. AOM ~hx determine whether TM perforation occurred
dx- PE= erythema and edema of EAC, tenderness on palpation of tragus
tx: retore EAC to natural acidic enviro with acetic acid in mild and topical antibiotics with corticosteroid in severe or TM perforated.
middle and lower respiratory infection
penumonia, bronchiolitis, epiglottis,croup, bacterial tracheitis
cervical lymphadenitis etio
1) localized abcteria infection. s aureas most common. can be s pyrogens, TB, B henselae= cat scratch disease
2) reactive lymphadenitis in response to infection of pharynx, teeth, soft tissue of head and neck
3) viral infection- EBV, CMV, HIV
4) kawasakii- unilateral
5) T gondii~ mono
6) structural lesions- branchial cleft cyst that gets infected
cervical lymphadenopathy P, Dx, Tx
mobile, tender, warm node. overlying erythematous skin. may have fluctuant. systemic sx-fever
dx: clinical. if unresponsive to tx, get CBC, tuberculin skin test, antibody titer for viruses if diffuse and persistent. image if need drainage and airway
tx- emperic antibiotics for s aureus and pyyrogenes. 1st gen cephalosporin or penicillin. IV if toxic
parotitis. etio
inflm of parotid salivary glands
etio: mumps (most common bf vaccine) and other virus cause bl. . acute suppurative parotitis (bacteria like s bureaus s pyrogens, tb)- unilateral and uncommon in kids. RF- decr salivary flow or stone
parotitis P, dx, tx
P: swelling above angle of jaw. fever. pus in oropharynx from stoniness’ duct
dx: ct, culture, viral serology
tx: viral-supportive. bacterial- antibiotics
complicaiton- abscess, osteomyelitis of jaw in bacteria
bacterial skin infection
impetigo, erysipelas, cellulitis, scarlet fever, toxic shock syndrome
impetigo
superficial skin infection of upper dermis
etio: s. aureaus most common
P: honey colored crusted or bullus lesion. face, nares. no fever. easily transmitted infection
dx- visual no culture
tx- topical mupirocin or antibiotics
complication- bacteremia, SSSS, glomerulnephritis
erysipelas
skin infection of dermal lymphatics
etio- GABHS
P: tender, erythematous skin with distinct border. face, scalp
dx- visual
tx- systemic tx with antibiotics
Complication: bacteremia, post strep glomerulonephritis, necr fas
cellulitis
skin infection in dermis
etio: GABHS and s aureus. break in epidermis
P: warm, erythema, tenderness. indistinct skin border
dx- visual.
tx: PO antibiotics
buccal cellulitis
HIB. unilateral bluish discoloration of cheek of unimmunized
perianal cellulitis
well remarked. GABHS
Nec Fas
pain and systemic sx out of proportion to physical findings. crepitus and hemorrhagic bull
staphylococcal scalded skin syndrome (SSSS)
S aureus, make exfoliative toxin.
fever, tender skin, bulla. large sheets of skin slough off in days
nikolsky sign- bulla extends with pressure)
wound care and IV antibiotics
scarlet fever, etio, epi, P
etio- GABHS makes erythrogenic toxin
epi-peak winter and spring. transmit by respiratory dropout
P: exanthum. fever, chillsm, malaise, exudative pharyngitis
exanthem- begin on trunk and mover peripherally, erythematous skin with tiny skin colored papule- scarlatinigorm, sandpaper rash. blanches with pressure. petechiae in skin creases = linear= pasta’s lines. desquamation of dry skin as infection resolve
scarlet fever dx, tx, complications
dx- clinical, throat culture for S pyrogens, pos rapid strep test for GABHS antigen
tx: prevent rheumatic fever. antibiotics- penicillin VK, I’m benzathine penicillin
complicaiton- post strep GN, rheumatic fever, post strep arthitis (not prevented by antibiotics), PANDAS- dev OCD or tic D (prevented by antibiotics)
toxic shock syndrome (TSS)
toxin mediated S aureus, increasing GABHS.
fever, shock, desquamating skin rash, multigrain dysfunction
tampon use.
Dx: need 5/6:
1) fever>38.5-101
2) hypotension SBP
diarrhea
viral- rotavirus, norwalk virus
bacteria- ETEC (ecoli= traveler’s diarrhea, no wbc in stool), ehec (e coli, wbc present in stool, cause hemolytic uremic syndrome via endotoxin= avoid antibiotics), shigella (bloody diarrhea, then seizure), salmonella (bloody or non bloody), campylobacteria (most common cause of bloody diarrhea), yersinia (mesenteric adenines - mimic acute appendicitis), c dif (after antibiotics, pseudomembrane on endoscopy), vibe choral (massive water loss)
rotavirus
most common infectious agent causing gastroenteritis. winter
V/D/dehydration. self limit in 4-7d
dx- ELISA stool. no wbc in stool
tx- supportive. transient lactose intolerance
norwalk virus
epi- closed populations
vomiting is prominent. 48-72hr.
dx-clinical
tx-supportive
diarrhea labs and tx
anon anion gap hypercholoremic metabolic acidosis bc bicarb loss in stool. WBC in stool predicted by gross or occult blood
fluid management, and antibiotics
HIV
> 95% kids is perinatal. 5% transmission. so all infant need 6wk zidovudine for post exposure prophylaxis and trimethoprim/ sulfamethoxazole for pneumocystis carinii pneumonia (PCP) prophylaxis until HIV DNA PCR neg at 4mo
first y- asx
early sx: failure to thrive, thrombocytopenia, recurrent infection, lymphadenopathy, parotitis, recurrent thrush, loss of dev milestones, severe VZV or zoster
dx: HIV materal ab persist as long as 18-24mo in infant so HIV dna pcr at birth and monthly. neg PCR at 4mo = noninflected
don’t get VZV and MMR bc live vaccine.
annual ophthalmologic exam for CMV retinitis
PCP
most common opportunistic infection in HIV kids
P: fever, hypoxia, interstitial pulmonary infiltrates
infectious mononucleosis
saliva- infect B lymphocyte
P: young- sx. older- fever up to 2wks, malaise and fatigue, pharyngitis, posterior cervical lymphadenopathy, hepatosplenomeglay (in 80%), macular or scarlatiniform rash, sx resolve in wks to mo
dx: CBC -atypical lymphocytes, inct LFT, thrombocytopenia, neutropenia. monospot
tx: supportive
complication: neuro - CN palsies, encephalitits. upper airway obstruction, amoxillin associated rash in misdx- idiosycratic not allergic- diffuse pruritic maculopapular rash. splenic rupture, malignancy
measles
rubeola. 10d. highly infectious
8-12d incubation. prodrome( 3C: cough, conjunctivitis and coryza. ) then transient enanthes (rash on mucous me) and activistic exanthema (rash on skin). photophobia and low grade fever
enanthem- kopek spots- small gray papuls on erythematous base on buccal mucosa- pathonogmonic
fever>101
compilcation- bacterial pneumonia most common and deadly.
tx- supportive, vit A, ig for post exposure prophylaxis
rubella
3 day measles. highly infectious
often asx. prodrome- upper respiratory sx and low grade fever. painful lymphadenopathy. exanthema- nonpruritic, maculopapular, confluent. fever
allergic bronchopulmonary aspergillosis
wheezing, eosinophilia, pulmonary infiltrates. common in pt with chronic lung disease ~ CF
ambiasis
protozoan entamoeba histolytica. ingest cyst in contaminated food and water. most asx. sx- mild colitis to severe dysentery
cramping abd pain, tenesmus, diarrhea with blood or mucus. wt los, fever, hepatomegaly, chest pain, respiratory distress, jaundice may be present
complication- ameboma- local inflm mass
dx- cyst or trophozoites in stool. serum ab assay. US or CT for abscess in liver
tx- metronidazole
giardiasis
G lamblia. fecal oral. in SB, diarrhea -voluminous, watery, foul smelling. bloating flatulence, wt loss, fever.
dx- stool for cyst and trophozoites, ELISA,
tx- metronidazole
malaria
flu like. cyclical fever correlate with RBC rupture and parasitemia. hemolytic anemia, splenomegaly jaundice, hypoglycemia
dx- thick and thin giemsastained peripheral blood smears
tx- dep on strain. chloroquine, quinine, doxy
toxoplasmosis
t gondii. cat feces
most asx or ~mono. present as focal seizure.2nd most common cause of infectious chorioretinits- ocular toxoplasmosis.
congenital: triad- hydrocephalus ,intracranial calcification, chorioretinitis
dx: sero, pcr, culture amniotic fluid, csf, blood
tx: if congenital, preg or imunocomp- sulfadiazine and pyrimethamine.
helminth
most asx. dx with 3 sep stool exam for ova and parasites.
pinworm-cellulose tape test on perianal region bf sleep
cystercosis
mexico. 20-50% epilepsy. taenia solium
4th ventricle-most common in neuro. hydrocephalus, stroke.
antiparasitic med for idivi with adult tapeworm
anticonvulsants for neurocysti
rickettsial infection
lyme, rocky mountain spotted fever, ehrlichoiosis (spotless- RMSF)
TB
children
fever w/o source
in 3-36mo age group, surly viral. pre-vaccine was due to pneumococcal and HIB. almost never bacteria now so no antibiotics
occult bacteremia
has dropped since vaccinate against pneumococcal and HIB
incr WBC with left shift
incr polys nd bands. concern for invasive bacterial infection
urine nitrite
made by gram neg bacteria.
pyelonephritis tx
amp/gent or cetriaxone. need to cover coli. enteric gram neg (klebsiella or proteus) and enterococcus. PO- cephalexin. Get US at end of antibiotic course. a RF is reflux so get VCUG to test for it if US is suspicious
