Infectious Disease Flashcards
Name three toxin mediated diseases caused by staph aureus
scalded skin syndrome
toxic shock syndrome
staphylococcal epidermal necrolysis
What is the D test?
determines if ther is macrolide inducible clindamycin resistance. Must be done if organism is sensitive to clindamycin and resistant to erythromycin.
If positive D test, do not treat with clindamycin
Treatment of boil or abscess if a mild, moderate vs. severe infection.
Mild: can often only be treated with incision and drainage. If oral antibiotic: TMP/SMX (if strep unlikely), clindamycin or doxycycline if > 8 years old
Moderate: have fever but otherwise healthy. Prescribe oral antibiotic as above
Severe: toxic appearing, sick, immunocompromised. Admit with IV antibiotic, vancomycin.
If critically ill, consider vancomycin and nafcillin
What infection control measures are necessary for highly resistant staphylococcus aureus?
isolate patient to private room
gown and gloves
wash hands with soap and water and or alcohol rub
dedicated items (stethoscope)
face mask and eye protection if doing something that makes splashes
consult cdc, health department before dc or transfer
What complications should you suspect if a child has S. aureus bacteremia?
osteomyelitis, endocarditis, thromboembolism, empyema more likely to occur with pneumonia
What are the symptoms and the cause of toxic shock syndrome?
TSS toxin-1
generalized red skin, hypotension, fever, diarrhea and multiorgan system involvement, > 3 systems. Desquamation of hands, feet occurs 1-2 weeks after illness
Treatment of toxic shock syndrome
fluids, nafcillin or vancomycin if MRSA and clindamycin which decreases toxin production
blood cultures are usually negative
What causes staphylococcal scalded skin syndrome and what are the symptoms
exfoliative toxins A and B
Fever, minimal friction applied to skin results in removal of superficial layers of epidermis : Nikolsky sign
extensive sloughing can occur though this is less likely to occur in older children
Complications to watch out for with staphylococcal scaled skin syndrome?
dehydration and superficial infection due to extensive skin sloughing
what causes Staphylococcus aureus food poisoning? What is the timing of symptom onset and what are the symptoms?
Preformed enterotoxin.
In < 4-6 hours after eating suspect food
self limited abrupt onset nausea, vomiting, diarrhea, abdominal cramps
What is the most common cause of catheter related bacteremia?
S. epidermidis
Staph epidermidis is usually always resistant to what antibiotic?
methicillin
Treatment for s. epidermidis
vancomycin +/- rifampin +/- gentamycin
S. saprophyticus usually causes what type of infection? How should it be treated
UTI in adolescent females.
TMP/SMX, nitrofurantoin, cephalothin
No 3rd gen cephalosporins, not effective
When is staph epi a contaminate and when is it not?
Contaminate in single blood culture with out risk factors or indwelling device
True infection in those who are immunocompromised, have indwelling catheter, NICU baby
coagulase negative staph most common cause of late onset sepsis in preterm infants esp. those < 1500 g
Who is at increased risk for Strep pneumoniae infections
Asplenic Very old or very young those with hypogammaglobulinemia HIV infection cochlear implants Alaska natives and native americans < 2 congenital immunodeficiency chronic disease (cardiac, pulm, renal) CSF leals DM immunosuppressive therapy
What is the most common cause of otitis media and how do you treat?
Strep pneumoniae
High dose amoxicillin 80-90 mg/kg/day
if no response in 48 hours broaden to Augmentin or 2nd or 3rd generation cephalosporin
When can an otitis media be observed?
children 6months to 2 years with unilateral disease and no otorrhea. > 2 years unilateral or bilateral with out otorrhea
must have close follow up and start antibiotics if no improvement in 24-72 hours
What is the antibiotic choice for strep pneumoniae due to possible penicillin resistance?
For bacteremia: ceftriaxone or cefotaxime until susceptibility is known
Meningitis: ceftriaxone, cefotaxime and vancomycin
Antibiotic recommendations for otitis media for those who are penicillin allergic?
cephalosporin, clindamycin, doxycycline (adolescents)
What diseases are caused by group A strep or strep pyogenes
pharyngitis impetigo, erysipelas, cellulitis scarlet fever rheumatic fever streptococcal toxic shock syndrome acute glomerulonephritis
What clinical findings make streptococcal pharyngitis more likely.
Temp > 100
tender cervical lymphadenopathy
exudative tonsils
If child > 2 years and has cough, rhinorrhea etc likely viral
In those < 2, they have thick purulent nasal discharge, low grade fever and decreased feeding
How is streptococcal pharyngitis diagnosed
rapid strep throat testing
if negative send culture
may wait on culture results before giving antibiotics as long as antibiotics are started within 9 days of infection to prevent rheumatic fever
What are the complications of streptococcal pharyngitis
otitis media, sinusitis, cervical lymphadenitis, peritonsillar/retropharyngeal abscess
rheumatic fever, glomerulonephritis
what causes scarlet fever and what is the presentation
streptococcal pyrogenic exotoxins (SPE A, B, C and F)
fine sand paper rash that starts on neck and upper chest and spreads
pastia lines in flexor creases, circumoral pallor
Impetigo diagnosis and complications
Vesicles that break open and ooze making a honey colored crust. Can lead to glomerulonephritis
Clinical features of erysipelas
strep infection in deeper layers of skin, to the dermis. Skin is erythematous and tender to touch with a well demarcated line
Complications of cellulitis from streptococcal infection
necrotizing fasciitis- destruction from infection down to subcutaneous tissue. Requires surgical debridement, IV penicillin and clindamycin.
recent / concurrent varicella infection is a risk factor
can result in post-strep glomerulonephritis
Treatment of strep pyogenes if penicillin allergic
cephalexin, or other cephalosporin, erythromycin or azithromycin if allergic to both penicillin and cephalosporins
Treatment recommendations for those with recurrent strep infections.
These individuals are thought to be carriers and antibiotics are usually not indicated except:
local outbreak of acute rheumatic fever or post strep glomerulonephritis
Outbreak in a closed community
family history of acute rheumatic fever
multiple (ping-pong) episodes of pharyngitis in a family despite appropriate antibiotics
can use clindamycin to try to irradiate carrier state
What are the differences in timing in the two causes of post-strep hematuria.
Ig A nephropathy < 5 days
glomerulonephritis: 10-21 days
What types of infection and who is most susceptible to Streptococcus agalactiae, Group B strep
bacteremia, meningitis, pneumonia
infants
Things to know about early onset Group B strep
occurs in 7 days of birth
obstetric complications and premature birth are common
septicemia > pneumonia > meningitis
Things to know about late onset Group B strep
Onset is after 7 days to 3 months
bacteremia with out a focus is most common presentation followed by meningitis
osteomyelitis
cellulitis-adenitis syndrome (bacteremic and require LP but often well appearing
Diagnosis and treatment of Group B strep
blood and CSF culture
ampicillin and gentamycin
once GBS is known pathogen can use ampicillin or penicillin G
Repeat
Most common cause of endocarditis in children
strep viridans
majority have underlying congenital heart defect or had rheumatic fever
cause of bacteremia in neutropenic patients
Name two species of enterococcus and the three types of infection it usually causes
E. faecalis and E. faecium
UTI, polymicrobial abdominal infections, bacteremia
What is the cause of enterococcus infection in an infant, symptoms and treatment
usually nosocomial in those with catheters or NEC
bradycardia, fever, apnea, abdominal distension
resistant to cephalosporins, penicillin and aminoglycosides and some even to vancomycin
if sensitive: aminoglycoside (gentamycin) plus ampicillin or vancomycin.
sensitivity testing important
Who is at risk for listeria monocytogenes
decreased immunity like transplant (renal), immunodeficiency, lymphoma, leukemia, neonates, pregnant women
What is infant listeria infection associated with and how is it treated
maternal amnioitis, brown stained amniotic fluid, preterm birth, pneumonia, septicemia and erythematous papular rash “granulomatosis infantisepticum”
Gram positive rod-can appear like diptheroids
ampicillin and an aminoglycoside (gentamycin)
use vancomycin or TMP/SMX if allergic to penicillin
use high dose ampicillin for meningitis plus aminoglycoside
What organism causes diptheria
corynebacterium diptheriae
Symptoms of diptheria
upper respiratory infection with gray-white pharyngeal membrane, hoarseness, sore throat, and low fever ( < 101) conjunctivitis and bull neck
laryngotracheobronchial diptheria results in hoarsenes, stridor and respiratory compromise
nasal diptheria more common in younger children with a profuse, mucoid grayish discharge
What are the toxic manifestations of diptheria
myocarditis with arrhythmia
proteinuria, cylindruria or microscopic hematuria
isolated peripheral neuropathy and Guillain-Barre like syndrome
Treatment for diptheria
equine antitoxin
erythromycin 2nd choice is penicillin
after recovery should be vaccinated
What is Corynebacterium jeikeium associated with
neutropenic patients and bone marrow transplant
often catheter related infections
must treat with vancomycin and must remove catheter
Type of anthrax and clinical manifestations of bacillus anthracis
cutaneous, GI and pulmonic
painless papule and vesiculates and forms a painless ulcer than painless black eschar
gram negative rod
Treatment for bacillus anthracis.
ciprofloxacin or doxycycline (penicillin only if susceptible)
same antibiotic for prophylaxis after potential exposure
What two types of illness dose Bacillus cereus cause
emesis type: short incubation 1-6 hours due to preformed heat stable toxin (fried rice at room temperature)
diarrhea type: 8-16 hour incubation, heat-labile enterotoxin production in the GI tract
gram positive rod
Presentation of clostridium difficile
antibiotic associated colitis, and occur up to 3 weeks after cessation of antibiotics
can be community acquired so consider in someone with prolonged bloody diarrhea
Diagnosis and treatment of clostridium difficile
C. diff toxin in stool, PCR assay
only test those who are symptomatic, carriage in young children is common and not pathogenic
10-14 days of oral metronidazole
may repeat for 1st recurrence
any further recurrence should be treated with oral vancomycin
Most common cause of gas gangrene and treatment
C. perfringens
PCN
if allergic: clindamycin, metronidazole, meropenem
What are the clinical forms of clostridium tetani. What causes the disease?
due to a neurotoxin produced
generalized: widespread distribution of toxin
Local: with toxin only near portal of entry
cephalic: distribution of the cranial nerves
neonatal: generalized
How does tetanus present
How does neonatal tetanus present
Incubation of 3-21 days, wound appears inconsequential
increasing stiffness of muscles of the jaw, neck and large muscles of back and lower extremities
spasms in response to loud nose, touch, light that cause paroxysmal contraction
risus sardonicus
neonatal forum: 4-14 days of life, child with excessive crying and unable to suck, trismus, contractions, spasms and seizures
Treatment of tetanus
quite stimulus free environment
neurologic blocking agents, mechanical ventilation
human tetanus immunoglobulin and metronidazole
When does a child need tetanus vaccine after an injury
wound is dirty and child has had < 3 immunizations or history is unknown: vaccine and tetanus immunoglobulin
wound is clean and immunizations are up to date, < 10 years - no treatment
wound is dirty and immunization are up to date in last 5 years - no treatment
If dirty wound and last vaccine > 5 years, clean wound with Tdap > 10 years or clean wound and unknown vaccination - need vaccine
Name the gram stain and clinically significant serogroups of Neisseria meningitidis. At what ages is infection most common?
Gram negative diplococcus
A, W-135, C, Y and B
children < 2 and then 15-19 year olds, leading cause of meningitis
How does meningococcus present?
fever, hypotension, diffuse purpuric lesions and DIC.
Who is prone to meningococcemia and therefore what should be tested?
terminal complement deficiency or those deficient in properdin.
CH50 or CH100 assay
Treatment for meningococcus?
Penicillin G or if allergic:
3rd generation cephalosporin
if allergic to both, meropenem and chloramphenicol
Sequela of meningococcemia?
hearing loss, neurologic disability, digit or limb amputation. skin scarring, renal failure
Discuss who should receive prophylaxis and what they should receive
household, day care (anyone attending daycare with the child in the last 7 days) and close intimate contacts (who you live with) and if you sit next to someone on a plane for more than 8 hours.
Give rifampin or IM ceftriaxone (preferred if pregnant)
Give prophylaxis regardless of immunization status
For health care workers, only if there was direct contact with oral secretions (intubation, mouth to mouth)
When does Gonococcal ophthalmia occur most commonly and how does it present.
mostly occurs in the newborn period as the infant passes through in infected birth canal.
2-7 days after delivery with bloody green or serosanguinous discharge
Discuss timeline of other possible eye infections during the neonatal period.
First 48 hours is likely due to chemical reaction from eye drops given at birth (1% silver nitrate, 0.5% erythromycin
7-14 days is more likely chlamydia
What is the management of an infant with gonococcal ophthalmia
blood culture and lumbar puncture, eval for disseminated infection
Ceftriaxone 50 mg/kg IM or IV x1 though many receive more antibiotics while awaiting negative blood culture
Describe the stages of pertussis
catarrhal: mild respiratory tract infection
paroxysmal: paroxysms of cough with inspiratory whoop
convalescent: symptoms gradually improve duration of 6-10 weeks
What is the diagnosis and treatment of pertussis. Who gets prophylaxis?
culture of PCR of nasopharyngeal secretions
elevated WBC with an lymphocytosis in children is suggestive (not adolescents)
If > 1 month treat with azithromycin, erythromycin, clarithromycin
TMP/SMX if macrolide allergic
if < 1 month- azithromycin
same medications for chemo prophylaxis for daycare and household contacts
What is the gram stain for Moraxella catarrhalis, what infections does it cause and how do you treat it?
gram negative diplococcus
Otis media
rarely bacteremia or bronchopulmonary infections
100% make beta lactamase. So….
treat with augmentin, cefuroxime, cefprozil, cefpodoxime, azithromycin, TMP/SMX
Gram stain for pseudomonas and what type of clinical situations should make you consider it as a possible pathogen?
Gram negative rod with a single flagellum
cystic fibrosis, nail puncture wound though a shoe, osteomyelitis and endocarditis in IV drug user, bacteremia in burn patients, chronic Otis externa. Immunocompromised
Hot tub rash
ecthyma gangrenosum (round indurated black lesion with central ulceration)
treatment of pseudomonas
pip-tazo, cefepime, aminoglycides, quinolones, imipenem
What illnesses does Salmonella usually cause. What is the gram stain?
gram negative bacilli that are generally motile
diarrhea
rarely meningitis, bone infections (sickle cell)
How do you treat salmonella
treatment increases risk of a carrier state and does not decrease symptoms. If uncomplicated gastroenteritis, no antibiotics.
Treat is child < 3, immunocompromised with 3rd generation cephalosporin
Describe typhoid fever symptoms and treatment
fever, leukopenia, rose spots (angiomas)
blood culture is only 60% sensitive, bone marrow or bile culture is more likely to be diagnostic.
3rd generation cephalosporin, ampicillin, TMP/SMX, quinolones.
Carrier state without gallstones (typhi likes to hide there) can be cleared with 4 weeks of ciprofloxacin
In what situations dose shigella occur?
day care, crowed conditions or institutions, native American reservations. Children 1-4 during July and October.
Lots of person to person transmission
What are the symptoms of shigella
Incubation 24-48 hours, fever, malaise, decreased appetite, vomiting, headache, diarrhea.
diarrhea is watery, small with mucus and or blood with lower abdominal cramps
Seizures in infants
rectal prolapse, pseudomembranous colitis, HUS,
Treatment of shigella and when can a child return to daycare after illness
Antibiotics shorten disease, treat those with severe disease, immunocompromised
ceftriaxone azithromycin
cannot return to daycare until more than 24 hours with out diarrhea and negative stool cultures
Gram stain of E.coli
gram negative rod
lactose-fermenting
name 5 phenotypes of E. coli causing diarrhea
ePec: enteroPathogenic: acute diarrhea in infants
eTec: enteroToxigenic: watery Travelers diarrhea
eIec: enteroInvasive: diarrhea and fever
eHec: enteroHemorrhagic: hemorrhagic colits and HUS
eAec: enteroAggrefative: persistent diarrhea in children in developing countries
Symptoms and treatment of enterohemorrhagic E. coli.
bloody diarrhea, hemorrhagic colitis, hemolytic uremic syndrome (kidney failure, thrombocytopenia with purpura and hemolytic anemia)
Do not give antibiotics.
Can not return to daycare until 2 negative stool cutlures after diarrhea has resolved.
Who is most at risk for H. influenza meningitis and what are the symptoms?
infants < 1 month
seizure, petechial rash, buccal cellulitis
What are some of the complications of H. influenza meningitis?
hearing loss
subdural empyema, brain infarcts, cerebritis, ventriculitis, brain abscess and hydrocephalus, intellectual disability
Treatment for H. influenza meningitis
Ceftriaxone or cefotaxime
dexamethasone to decrease incidence of hearing loss and neurologic sequelae
Describe the presentation of epiglottitis due to H. influenza
high fever, dysphagia, drooling, tripod position to breath
cherry red epiglottitis
Do not try to examine the uncooperative child unless ready to secure airway
What organism is buccal cellulitis associated with and what does it look like?
H. influenza and usually is bacteremic,
palpable on both sides of the cheek and purplish in color
What is now the most common etiology for bacteremic periorbital cellulitis?
Common cause of preseptal cellulitis?
Pneumococcus
S. aureus and group a strep from minor trauma
What should be done with occult bacteremia secondary to H. influenza?
results in 30-50% developing meningitis or other deep focal infection. Must treat with antibiotics.
What is the antibiotic of choice for invasive hib infection vs. non-invasive infection
Invasive: 3rd generation cephalosporin: ceftriaxone, cefotaxime
Non-invasive: amoxicillin or augmentin if not responding
Who gets chemoprophylaxis if they have been exposed to invasive Hib? What antibiotic is used?
Rifampin to household contacts and daycare attendees
to all household members if one person is immunocompromised or < 4 years of age and incompletely immunized
daycare if they have had two cases in the last 60 days
What is the gram stain for Yersinia pestis. What disease does it cause? How is it transmitted?
gram negative coccobacillus
plague, large lymphadenopathy that supinates, (bubonic) and can result in sepsis
fleas, rodents or direct contact with skinning animals
Diagnosis and treatment for Yersinia pestis?
culture, serology. Occurs more frequently in desert south west.
gentamycin, streptomycin
Gram stain for Yersinia enterocolitica and what disease dose it cause?
gram negative coccobacillus
makes endotoxin and enterotoxin, people get sick after eating contaminated food, especially pork (chitterlings) causes a GI disease
Older children can get a pseudoappendicitis syndrome where they clinically present like they have appendicitis
Who is at risk for bacteremia from Yersinia enterocolitica and what is the treatment
very young, those with iron overload
treat those with bacteremia and immunocompromised with TMP/SMX, aminoglycosides
What is the gram stain for Legionella pneumophila and what sort of illness does it cause?
gram negative bacilli, found in water and transmitted via aspiration
legions of problems:
diarrhea, CNS symtpoms, renal disease plus pneumonia
How do you treat legionella?
Azithromycin or quinolones
How is brucellosis transmitted, and what symptoms does it cause?
zoonosis transmitted to humans via unpasteurized milk, inhalation or handling carcasses.
Affects heart- culture negative endocarditis, lungs, GU tract (orchitis, abortion), endocrine (thyroiditis, adrenal insufficiency), sacroiliitis, granulomatous hepatitis.
When should you check for brucellosis and how do you treat it?
Fever of unknown origin. Culture is difficult and takes a long time.
Doxycycline for 6 weeks and aminoglycoside for 2 weeks or
doxycycline and rifampin for 6 weeks,
if less than 8 years old TMP/SMX and rifampin
Gram stain for Francisella tularensis, how is the disease transmitted, and what are the symptoms?
gram negative pleomorphic bacillus
tularemia
prevalent in Arkansas, Missouri and Oklahoma
ticks, blood sucking flies or can be ingested (rabbits)
fever, chills, myalgias and arthralgias with an irregular ulcer at site of inoculation with lymphadenopathy that may suppurate
How do you diagnose and treat tularemia
clinical syndrome confirmed with serologic testing
gentamicin or stretomycin
How does bartonella present?
> 3 weeks of chronic, tender, regional lymphadenopathy with history of cat exposure
Enlarged node with resolve in 4-6 weeks but 25% will suppurate.
Describe an atypical presentation of bartonella
Parinaud’s: patient is inoculated near the eye and gets conjunctivitis and ipsilateral periauricular lymphadenitis.
other form: hepatosplenic granulomas, FUO, aseptic meningitis, encephalopathy
How do you treat bartonella?
Can use PCR and serum antibodies to diagnose
Do not incise and drain-will cause persistent sinus tract
If biopsied will show necrotizing granulomas
symptom relief as it will resolve in 2-4 months, may aspirate lymph node for symptom relief
may treat with azithromycin early on or if severely ill
How to treat pasturella. What has usually happened to the patient to be infected?
cat bite, usually deep puncture wound
isolated infection: penicillin
however, usually concern for mixed flora so often Augmentin is used
if penicillin allergic: TMP/SMX and clindamycin
How does campylobacter present?
fever with diarrhea / gastroenteritis, stool can be bloody
febrile seizures, can mimic appendicitis ir intussusception
can cause guillain-barre syndrome
How is campylobacter treated
azithromycin, erythromycin
What test do you get if exam mentions a neonate with citrobacter growing in blood or CSF.
CT/MRI to look for brain abscess
What is the gram stain for Rickettsia rickettsia and what disease does it cause, with its symptoms
gram negative coccobacillus
Rocky Mountain Spotted Fever
fever, headache, arthralgias, diarrhea, abdominal pain
rash-distal extremities progresses from macular popular to petechial to purpura
hyponatremia and thrombocytopenia are helpful clues
history of tick bite in the south east plus Missouri and arkansas
How is q fever, coxiella burnetti, transmitted and how do you diagnose?
zoonosis transmitted to humans via inhalation of aerosol from infected animal, usually in slaughterhouses or products of conception from birthing an animal. (cattle, cats or conception =coxiella)
serology or staining biopsy tissue
How do you treat rickettsial infections. (includes q fever)
doxycycline even for those < 8 years of age
Describe symptoms, lab findings and treatment of Ehrlichia /Anaplasma
Rocky Mountain spotless fever
small gram negative intracellular organisms
human monocytic ehrliciosis and human granulocytic anaplasmosis.
HME: texas, Oklahoma, Missouri and Arkansas
HGA: northeast and Midwest
can have a rash with fever, viral syndrome and leukopenia, thrombocytopenia
think tick bite and pancytopenia
usually isolate in culture, PCR or seen in WBCs
treat: doxycycline
How does fusobacterium present?
anaerobe causes Lemierre disease that causes internal jugular vein thrombophlebitis or thrombosis with signs of septic lung emboli.
Fever, sore throat that progresses to severe neck pain and unilateral neck swelling, trismus and dysphagia
Treat with metronidazole
Describe usual TB symptoms in an infant
non-productive cough, wheezing especially at night.
CXR with hilar lymphadenopathy
lymph nodes can compress bronchial structures causes air trapping- emphysema
Describe the pleural effusion that can be seen in children with TB.
Many have an asymptomatic pleural effusion
lymphocyte count 1000-6000, low glucose, high protein, elevated LDH, usually smear will be negative
Describe TB meningitis findings in children
usually 6 months to 4 years
caseous cession in the cerebral cortex or meninges which seeds the subarachnoid space. can cause a communicating hydrocephalous, SIADH
CSF protein is elevated, glucose is low with CSF WBC count elevated with lymphocyte predominance
What is the most common extra pulmonary manifestation in TB
lymph node involvement
anterior and posterior cervical triangle, submandibular and supraclavicular lymph nodes
Common symptoms of TB in adolescents
fever, weakness, night sweats and weight loss
cough, pleuritic chest pain, hemoptysis
upper lobe infiltrate and hilar lymphadenopathy
Who gets screened for latent TB infection?
HIV or high risk for HIV
close contacts of those with TB
IV drug users
homeless
migrant workers
residents in long term care facilities
patients who are about to start immunosuppressive therapy
children traveling to or immigrating from endemic countries
children with symptoms suggestive of disease
How do you screen for TB?
TST: preferred for those < 5
IGRA: preferred in children who have had the BCG vaccine and are > 5 years old or children who are unlikely to return in 48-72 hours
What are some caveats to TST testing
10% of children are initially anergic and actually have TB, it also takes 10-12 weeks for positive test after exposure.
so if skin test is negative in someone recent exposed, treat and recheck in 10-12 weeks
TST is only contraindicated when there has been a necrotic skin reaction to previous tests
For who is a 5 mm TST test considered positive
Those at high risk:
CXR finding or those with symptoms consistent with disease
HIV or major cell mediated dysfunction
fibrotic changes on CXR consistent with prior TB
close contacts of a documented case
immunosuppressed patients, > 15 mg of pred daily
For whom is a 10 mm TST considered positive
moderate risk: homeless healthcare workers recent travel or birth in an endemic area IV drug users prisoners nursing home patients and staff diabetics, chronic renal failure children < 4 immunosuppressant therapy < 15 mg of pred daily
For whom is 15 mm TST considered positive
Every body else
What do you do if the TST is positive?
Chest xr, sputum for AFB smear, PCR, culture times 3.
basically do they have active infection?
Who gets treated for LTBI?
If no active disease is present treat all previously untreated persons with positive TSTs
Treat children < 4 and those with HIV who are close contacts of those infected while awaiting second test in 10-12 weeks
How do you treat LTBI
isoniazid for 9 months
If known exposure to resistant organism or intolerance treat with rifampin for 6 months
How is TB treated?
4 drug regimen of: rifampin isoniazid pyrazinamide ethambutol or streptomycin 3 drug regimen of rifampin isoniazid pyrazinamide in the us: 2 months of 4 drug regimen and INH and rifampin for an additional 4 months if HIV on protease inhibitors give rifabutin instead of rifampin
What are the side effects to TB treatment
Give pyridoxine B6 to prevent peripheral neuropathy, particularly pregnant adolescents, those with low meat and milk diets, breast fed infants
All three RIP drugs are hepatotoxic, labs only if there are symptoms
rifampin makes everything orange, and OCP don’t work well
ethambutol (you see like paul day) decrease color acuity, screen patient with initial eye exam and monitor for symptoms
What is actinomyces, how does it present and how is it treated?
microaerophilic / facultative anaerobic organism
yellow sulfur granules
cervicofacial involvement caused by a dental infection
PID when there is an interuterine device, can be associated with appendicitis
treat with penicillin or ampicillin
clindamycin, doxycycline
List the various illnesses that can be caused by chlamydiae
obligate intracellular parasites
C. psittaci: pneumonia and splenomegaly with history of bird exposure
C. pneumoniae: CAP in children > 5 years old, causes bronchospasm
C. trachomatis: Gu infections and trachoma:
chronic external eye infection resulting in cataracts, causes a chronic folliculiar keratoconjunctivitis (eye ointment at birth does not prevent chlamydial infection, get gonorrhea instead)
also causes neonatal pneumonia with a staccato cough
How is leptospirosis spread, how does it present and what is the treatment.
Zoonosis due to contact with infected dog or water
Range of symptoms, myalgias, fever headache to Weil disease: severe hepatitis, (bilirubin much higher than LFTs) renal failure and hemorrhagic complications,
What organism causes Lyme disease and how is it transmitted?
Borrelia burgdorferi via the ixodes tick
ticks usually transmit infection during the nymph stage, cause they are small
Ticks are most likely to transmit disease after 2 days of feeding
What are the stages and associated symptoms of Lyme disease?
Stage 1: early localized disease
erythema migrans. can also have myalgias, arthralgias, headache, fever
Stage 2: weeks to months later: early disseminated
hear problems (AV block), neuritis (bells palsy, foot drop aseptic meningitis, lymphocytic meningitis)
Stage 3: Months to years later, late disseminated disease:
oligoarthritis, or migratory arthritis
What is the laboratory diagnosis for Lyme disease
Elisa test or IFA which if positive if followed with a western blot.
Only treat those who both tests are positive
What is the treatment for Lyme disease?
Early disease: oral doxycycline or amoxicillin for 14-21 days
Late disease: same as above but for longer duration, 28 days. If no response retreat with same or use ceftriaxone
For cardiac and neurologic symptoms treat with ceftriaxone
Who gets cutaneous candidiasis and how is it treated?
Infants 2-4 months with diaper rash (bright red, sharp boarders and pinpoint satellite papules and pustules)
Keep dry-topical nystatin
Nail infection in thumb suckers
Chronic mucocutaneous candidiasis: T cell problem
< 2 years old, oral, facial rash, alopecia, nail disease
Treat with fluconazole
Who gets oropharyngeal candidiasis, what is the presentation and how is it treated
infants < 5 months of age
immunocompromised, on antibiotics
pearly white plaques that removal results in pin point bleeding
oral nystatin, clotrimazole in the immunocompetent
fluconazole in the immunocompromised
What should you do if candida is found in a blood culture?
It's NOT a contaminate, TREAT! Get an eye exam looking for cotton-like chorioretinitis Check the brain for dissemination Can have hepatic and renal candidiasis Take out the catheter
Name three syndromes that can result from candidemia
septic peripheral thrombophlebitis
septic thrombosis of the great central veins
Hepatosplenic candidiasis
How to treat Candidemia
Amphotericin B in neonates
Fluconazole echinocandin (micafungin, caspofungin): non neutropenic
In critically ill, neutropenic: echinocandin or amphotericin B
Resect any suppurative peripheral vein
suspect thrombosis of great vessels if there is edema of upper body and persistent candidemia
What symptoms are caused by Cryptococcus and how do you diagnose and treat it?
usually self limited low grade fever cough and pulmonary infiltrate
in immunocompromised (T-cell problem): meningoencephalitis
CSF cryptococcal antigen test or india ink
treat meningitis with amphotericin B and 5 flucytosine
fluconazole in those less ill and for life in those with HIV after initial treatment of a cryptococcal infection
What symptoms are caused by Coccidioides and how do you diagnose and treat it?
Found in southwest US and northern Mexico
inhaled and then days to weeks later causes a flu like illness with arthralgias, erythema multiforme and erythema nodosum. Pulmonary coin lesion
serology or histopathic techniques
Treat with fluconazole
What symptoms are caused by histoplasma and how do you diagnose and treat it?
Mississippi and ohio river valley, bird and bat droppings
most infections are asymptomatic and later present with a calcified lesion on CXR
can present as interstitial pneumonia, splenomegaly, palate ulcers, splenomegaly, 1/3 have anemia / pancytopenia
urine antigen, culture
treatment: itraconazole
What symptoms are caused by Blastomyces what is the treament
Arkansas and Wisconsin hunters and loggers
can disseminate to skin and bone
Treatment: itraconazole
What types of disease dose invasive aspergillosis cause and in whom? How is it diagnosed and treated?
pulmonary, sinusitis, cerebral or cutaneous
in immunocompromised particularly those with new or relapse of heme malignancy and stem cell transplant patients
Need biopsy of tissue of diagnosis though serum galactomannan is suggestive.
Treat with voriconazole
What two diseases are caused by Malassezia Furfur and how are they treated?
- pityriasis versicolor (hypo and hyper-pigmented lesions that scale) spaghetti and meatballs on a skin scraping
Treatment: selinum sulfide or oral fluconazole - NICU baby- fever, pulmonary infiltrates, leukocytosis, thrombocytopenia and receiving TPN with lipids
if it says it needed olive oil overlay to grow
Treatment: amphotericin B
Clinical presentations of sporotrichosis and the treatment
cutaneous and lymphangitic: itraconazole, K iodine solution
pulmonary and disseminated form: amphotericin
sprothrix schenckii associated with plants
Mucor, Rhizopus and cunninghamella cause what type of disease and in whom? What is the treatment?
pulmonary infacts, cavitary pneumonia, black necrotic spot in the nose or paranasal sinuses and extends intracranially
amphotericin B and surgical debridement
Possible regimens for PCP prophylaxis
TMP/SMX, pentamidine, dapsone
What is toxoplasmosis and who is the definitive host. How do you test for it?
caused by toxoplasma gondii, protozoa, sporazoa
cats are the definitive host shedding oocytes in feces
Elevated IgM
If pregnant mom becomes infected with toxoplasmosis during pregnancy, when is the infant more likely to be infected and when is the infant more likely to have serious sequela?
baby is more likely to have a congenital infection if the disease is acquired later in pregnancy (25% in 1st trimester, 54% second trimester, 65% 3rd trimester).
however, more severe disease the earlier infection is acquired in pregnancy
Name the clinical findings of toxoplasmosis infection in the newborn
microcephaly hydrocephalus hepatosplenomegaly maculopapular rash or thrombocytopenia purpura chorioretinitis cerebral calcifications (parenchyma)
How is toxoplasmosis treated in the pregnant mother and how is it treated in the infant?
if 7-34 weeks and mom is infected: spiramycin
If it is confirmed that baby is infected too: pyrimethamine, sulfadiazine and leucovorin
If mom is after 34 weeks: pyrimethamine, sulfadiazine and leucovorin
After delivery regimen continues until infection is confirmed
If baby is infected treatment continues for 12 month with eye exams at 3 and 6 months
Describe the other three ways that toxoplasmosis can present
mono like illness in the immunocompetent
CNS infection with multiple mass lesions in the immunocompromised
Ocular: yellow-white patches with irregular scaring and pigmentation
treat with pyrimethamine, sulfadiazine and leucovorin
How is cryptosporidium transmitted, what symptoms does it cause and what is the treatment?
passed in animal and human feces
watery diarrhea that is self limited in the immunocompetent
in immunocompromised watery diarrhea refractory to medications
small and round on acid fast stain
treat with nitazoxanide
What type of illness does isospora belli cause and who is it treated?
in the immunocompromised causes watery diarrhea
acid fast but large and oval
TMP/SMX
What type of illness dose cyclospora cause and what is the treatment
also acid fast, causes diarrhea, usually on imported fruits and vegetables from developing countries
TMP/SMX
What are the four types of malaria and how is it transmitted?
Plasmodium vivax, plasmodium ovale, plasmodium malariae and plasmodium falciparum.
anopheles mosquito
How is malaria diagnosed
Thin and thick blood smears in febrile traveler
What is seen on blood smear and what are the symptoms of P. falciparum
banana gametocyte on blood smear
causes the most severe illness: cerebral malaria with seizures, stupor, coma, hypoglycemia, renal failure, respiratory failure, severe anemia and shock
chloroquine resistance
What symptoms are associated with P. ovale and vivax?
Which type of malaria is most likely to cause nephritis?
anemia, hypersplenism and relapsing disease
P. malariae is most commonly associated with nephrotic syndrome
What is the treatment for P. vivax, ovale and malariae?
chloroquine
and primaquine for vivax and ovale to eradicate hyponozoites from the liver
What must one screen for before prescribing primaquine
G6PD
What medications are given for malaria prophylaxis?
chloroquine if no resistance known in the region
mefloquine, doxycycline or atovaquone/proguanil in chloroquine resistant areas
what symptoms are caused by Babesia microti and how is it transmitted?
febrile hemolytic anemia especially in the elderly and asplenic
fever, sweats, myalgias, shaking chills, hemoglobinuria
Ixodes tick (same that transmits Lyme)
How is bebesia diagnosed and how is it treated
intra-RBC maltese cross (tetrad)
clindamycin and quinine or atovaquone and azithromycin
How do you diagnose and treat Entamoeba histolytica?
institutionalized, immigrants, MSM
stool for O and P
if liver abscess, aspirate often shows no PMNs or ameba, diagnose with serology
asymptomatic infection: paromomycin or iodoquinol with follow up stool studies
Liver abscess or invasive colitis: metronidazole followed by paromomycin or iodoquinol
What are the symptoms of Giardia
diarrhea due to infected water
found in campers, travelers, children and MSM
smelly diarrhea, flatulence and if chronic also causes weight loss
How do you diagnose and treat Giardia?
microscopic examination of 3 stool sample or giardia antigen test
Nitazoxanide, tinidazole and metronidazole
Trypanosoma causes which two diseases?
African sleeping sickness: trypanosoma brucei via the tsetse fly
Chagas disease: central America, T. cruzi transmitted by kissing bugs
What are the symptoms of Chagas disease and how is it treated
unilateral firm edema of the eyelids, fever, generalized lymphadenopathy and malaise
months to years later: heart block, CHF, achalasia, megaesophagus, megacolon and occasionally CNS symptoms.
benznidazole or nifurtimox
what are helminthic organisms
multicellular worms
do not replicate in the body
cause eosinophilia
Hos is Ascaris lumbricoides spread, what symptoms does it cause and how is it treated?
children often infected from playing in the same area where they poop
Larval forms cross into the pulmonary vasculature to go to the epiglottis to be swallowed, while in the lungs cause cough, fever, rales, shifting atelectasis.
Diagnose with finding eggs in stool
Treatment:
albendazole or ivermectin
How are pinworms spread? What are the symptoms
eggs ingested by oral contact with contaminated hands, toys, fomites
pregnant female lays eggs on the surface of the skin near anus at night, between 10-11 pm
puritis ani
autoinnoculation
How do you diagnose pinworms
what is the treatment
visualization of worms clear adhesive tape test for eggs pyrantel pamoate or albendazole single dose and then repeated in 2 weeks wash bedding
What are the symptoms and treatment of hookworm infection or necator americanus
anemia, weakness and fatigue
cutaneous larva migrans
failure to thrive
albendazole or pyrantel pamoate, mebendazole
What are the symptoms of trichinosis and treatment
abdominal pain, nausea and vomiting, then go to muscle and cause muscle pain
calcifications occur in skeletal muscle,
myocarditis and eye involvement
confirm diagnosis with rising titers and muscle biopsy
mebendazole and albendazole
What are the symptoms of whipworm infection and how is it treated
Trichuria trichiura: southern US
fever, abdominal pain, weight loss. itching, diarrhea, bloody stools
Eggs in stool
mebendazole, albendazole or ivermectin
What are the symptoms of strongyloides stercoralis infection and how is it treated?
GI and pulmonary symptoms
larva currens a surpiginous rash with erythematous tracks.
serial stool samples for larvae
treat with ivermectin
What are the symptoms of toxara canis, and what is the diagnosis and treatment?
visceral larva migrans
fever, hepatosplenomegaly, migratory pneumonia, hyergammaglobulinemia and eosinophilia
hypereosinophilia with increased titers of isohemagglutinin to the A and B blood group are presumptive evidence of infection
consider in a child with pica that eats a lot of dirt
observe or treat with albendazole
Describe Taenia solium infection
if cysticerci are ingested taeniasis develops (tape worm grows in intestines)
if egg-contaminated food is ingested: cysicercosis which cause cysticerci in eyes and CNS and they do not cause issues until organism dies
in neurocysticercosis the resulting inflammation causes seizures
head CT with single or multiple cysts which then progresses to calcified granuloma
What is the treatment for tapeworms?
Intestinal tapeworms: praziquantel or nilosamide
neurocysticercosis: albendazole or praziquntel with steroids
If ocular or spinal cyts are present do NOT treat: causes irreparable damage
Which schistosoma infects the bladder? How are all schistosoma treated?
schistosoma haematobium- hematuria
swimming in infested endemic waters
1 day of praziquantel and repeat in 1-2 months
What type of viruses are herpes viruses
double stranded DNA
HSV, CMV, EBV, HHV, 6, 7 and 8 and varicella
How does HSV 1 present?
orofacial infections
primary infection: vesicular lesions and ulcers are usually localized to the oral mucosa, lips and surrounding skin
recurrent infection: outer lip ulcer
What is herpetic whitlow and what should you not do?
HSV infection of the fingers that is painful. Do not surgically open the infection as it may make it worsen and spread.
How is HSV diagnosed
Tzank test can be done and will show multinucleated giant cells
now test with PCR, direct florescent antibody testing
Finding in recurrent HSV eye infection
Can autoinnoculate the virus in the eyes.
Results in keratitis and is the most common infectious cause of blindness in industrialized nations
branched fluorescent staining corneal ulcers
What are most cases of HSV from and when is C-section recommended
most casese are from intrapartum contact.
C-section is recommended if mother has signs or symptoms or genital herpes or a prodrome at time of delivery
otherwise vaginal delivery
infant more at risk if mom has primary infection as opposed to recurrence
60-80% of women with an infant with neonatal HSV have no prior history of HSV
What are the three clinical syndromes of neonatal HSV and when do they manifest?
45% are skin, eye and mouth-1-2nd week of life
30% CNs only, 2nd to 3rd week
25% - disseminated 1st to 2nd week
think about it in baby with skin lesions, conjunctivitis, fever, seizures, sepsis
What is the work up for neonatal HSV infection and where do lesions commonly occur?
HSv culture of mouth, nasopharynx, conjunctivae and anus
HSV culture and PCR of skin lesions and CSF
blood samples for HSV PCR and liver enzymes
lesions occur at sites of trauma, eye margins where the fetal scalp monitor was
How do you treat neonatal HSV?
Acyclovir
14 days for SEM
21-28 days for CNS and disseminated disease
continue suppressive therapy for 6 months to prevent skin recurrences
How does HSV encephalitis present in older children
constitutional symptoms, altered mental status, focal neurologic signs, temporal lobe seizure signs (abnormal behavior, strange smells)
What is the treatment of HSV in children and adolescents
acyclovir, famciclovir, valacyclovir
foscarnet if resistant to acyclovir
What is the incubation period for varicella zoster virus
10-21 days
up to 28 if child received IVIG
What is the presentation of chicken pox
fever, headache, malaise followed by 24-48 hours with vesicular exanthem (dew drops on a rose petal)
crops of vesicles for 3-5 days worse in areas of trauma or eczema
Until when is a patient with chickenpox contagious
1-2 days prior to onset of rash until all lesions are crusted over
If patient in hospital has been exposed what are the infection precautions?
negative pressure room for 8-21 days after exposure
Describe the complications of varicella
secondary bacterial infection with strep pyogenes or staph aureus
Reye syndrome with aspirin use
pneumonitis
progression to pneumonia in older age groups
CNS complication is transient cerebellar ataxia and encephalitis
Who is at risk for disseminated varicella infection and what are the symptoms?
those who can not mount a t cell specific immune response:
HIV/AIDS, lymphoproliferative malignancies, STEM cell transplant, congenital immunodeficiencies
severe abdominal or back pain before the rash
high fever
liver involvement, pneumonitis, low platelet count, coagulopathy, encephalitis, renal dysfunction
If a pregnant mother gets varicella, when is the infant most at risk and what are possible birth defects?
8-20 weeks gestation most likely to have birth defects including
cicatricial skin scarring, limb atrophy, microcephaly, cortical atrophy, seizures, chorioretinitis and neurologic defects
What should be done if a pregnant woman is exposed to chicken pox
Give zoster immunoglobulin with in 10 days of exposure
when is an infant at risk for neonatal varicella? Which infants may manifest zoster infection?
infant born to mom who got varicella < 5 days to 48 hours after delivery are at risk for severe neonatal infection
infant whose mom had varicella at any stage during pregnancy or acquire in the first few months of life may manifest zoster
What is the treatment for varicella
Infected infants and immunocompromised: Iv acyclovir
adults/adolescents who present in the first 24 horus of rash: oral acyclovir
Who should get VARIZIG?
Significantly exposed susceptible
susceptible:
immunocompromised
pregnant women
newborns whose mom had infection < 5d before to 48 hours after delivery
hospitalized premature infant > 28 weeks born to antibody negative mom
hospitalized premature infant < 28 weeks
SIGNIFICANT EXPOSURE:
active case in same household
active case in same room
visit by a contagious person
face to face indoor play with an active case
intimate contact with a person with active zoster
Up to when can you give VARIZIG and when should you treat?
Up to 10 days after exposure
If not received by day 7 consider acyclovir
may not prevent but just delay infection by 28 days
do not give if there is an active infection
Can give vaccine to those > 12 months who can have a live vaccine within 3 days but up to 5 days of exposure
How does zoster present and how is it treated
1-2 adjacent dermatomes with thoracic, lumbosacral or cranial nerve most frequently involved
No benefit to prednisone
famciclovir and valacyclovir decrease post herpetic neuralgia
pain control
How is CMV transmitted?
contact with infected blood, urine, respiratory secretions, transplantation
1% of all newborns are congenitally infected with CMV
most are clinically silent and occur in moms who already have immunity
can be transmitted via breast feeding
Who is at risk of congenital CMV infection and what are the systemic findings of an infant with severe disease?
Exposed in utero and it is mom's primary infection (ie. mom does not have any antibodies) IUGR hepatosplenomegaly jaundice thrombocytopenia petechiae/purpura (blueberry muffin) microcephaly cerebral atrophy chorioretinitis sensorineural hearing loss periventricular calcifications
Even if asymptomatic at birth, what is the long term sequela? How is it diagnosed and treated?
subtle growth retardation, 15-20% will have hearing loss
isolation of virus from urine, stool or respiratory secretion or in CSF within 2-4 weeks after birth
ganciclovir or valacyclovir watching from thrombocytopenia
How does CMV present in older children
mono like illness but heterophile negative
will get a rash if given ampicillin/amoxicillin
How does CMV present in the immunocompromised and how is it treated?
Post transplant is worse if patient did not have CMV prior to transplant:, encephalitis, hepatitis, retinitis, colitis, pneumonitis, adrenalitis
In AIDS/HIV: chorioretinitis, esophagitis, pneumonitis colitis
Ganciclovir, foscarnet or both
ganciclovir causes granulocytopenia and thrombocytopenia
What infection and typical symptoms does EBV cause?
infectious mononucleosis
incubation 1-2 months
pharyngitis, tonsillitis, fever, lymphadenopathy and abnormal liver function
lymphocytosis with atypical lymphocytes
50% have splenomegaly
if given amoxicillin or ampicillin will have a rash
How does EBV present in younger children?
children less than 4 can have fever and hepatosplenomegaly
prolonged fever may be the only manifestation
monospot has 50% sensitivity in children 2-4 years old and rarely positive in those < 2
Discuss the four type of EBV specific antibodies and how to interpret them
VCA-IgM:
is positive if the patient has an active primary EBV infection or very recent infection
VCA-IgG:
If positive the patient has had EBV at sometime in their life
EBNA (nuclear antigen):
appears 2-4 months after infection and then continues to be positive
Anti-early antigen:
is often positive in early infection however in many people it can be positive for life
what is the treatment for EBV
Avoid contact sports and supportive care
What other diseases is EBV associated with in the immunocompromised
oral hairy leukoplakia, Burkitt lymphoma, nasopharyngeal carcinoma, post transplant and x-linked lymphoproliferative syndrome
Describe the symptoms of HHV-6.
can be asymptomatic though usually
fever for 3-5 days followed by cessation of fever and the appearance of a macular to macular popular rash
a likely culprit of febrile seizures
How does Rubella, german measles transmitted and what are the symptoms?
person to person transmission of infected droplets
most common in late winter and spring
fever, rash posterior auricular, occipital tender lymphadenopathy
cough, headache myalgia prodrome prior to the rash
rash: macules on the face that spread downward and is often gone from the face by the time it reaches the legs
forchheimer spots on the soft palate
Discuss the difference in outcomes depending on the trimester a mother contracts Rubella
1st trimester: 90% infection risk with all children having defects
2nd trimester: 54% infection risk with likelihood of defect decreasing to 25% by end of second trimester, most likely hearing and neurological defects
Late weeks of gestation: 60-100% risk of infection but, usually non-teratogenic
what are the manifestations of congenital rubella
Thrombocytopenic purpura (blueberry muffin rash)
radiolucencies in the metaphyseal long bones
hepatosplenomegaly
hepatitis
hemolytic anemia
bulging anterior fontanelle
CSF pleocytosis
Congenital heart disease
sensorineural deafness (may be only manifestation if infection is after first 8 weeks of pregnancy)
cataracts with microphthalmia
congenital glaucoma
retinopathy with patchy deep pigmentations
intellectual disability
How is Rubeola or measles spread. What are the symptoms?
respiratory droplets
symptoms about 10 days after exposure
cough, coryza and conjunctivitis (with photophobia)
fever, koplik spots (whitish spots on erythematous base) in buccal mucosa prior to the rash
rash starts and hairline and moves downward, lasts for 5 days
sometimes vomiting, diarrhea and abdominal pain
Discuss what symptoms of rubeola are worsened by a vitamin deficiency
vitamin A deficiency makes particularly eye disease worse. with corneal ulcers and loss of vision
What are some of the CNS complications of rubeola
encephalomyelitis in 0.1%, with high mortality and survivors with long term sequela of motor, cognition and behavioral problems
subacute sclerosis panencephalitis: develops 7-10 years after infection, behavioral and intellectual decline
Is there a congenital rubeola syndrome
No
what is the treatment for rubeola
vitamin A can reduce eye abnormalites
vaccine if given within 72 hours of exposure and is the intervention preferred for outbreaks in schools.
During an outbreak can give to children as young as 6 months old however does not count toward their vaccine series
IvIg to susceptible household members or close contacts to infected patient for whom the vaccine in not indicated such as < 1, pregnant and immunocompromised
must give in 6 days of exposure
What virus causes acute hemorrhagic cystitis?
Adenovirus
Define antigenic shift and antigenic drift
antigenic shift: major change to the viral hemagglutinin or neuraminidase on the outer surface
antigenic drift: minor changes to the virus
What are the symptoms of influenza and what type of complications can occur
fever, chills, headache myalgias after 24 hours rhinitis and lower respiratory symptoms
1. viral bronchopneumonia: days 3-5 of illness
2. secondary bacterial pneumonia: S. aureus and s. pneumoniae
3. diffuse viral hemorrhagic alveolitis
acute myositis, rarely severe disease including myocarditis and CNS disease
How is influenza diagnosed and treated
EIA antigen or PCR
oseltamivir and zanamivir (contraindicated in those with asthma or chronic lung disease)
amantadine and rimantadine-only have activity against Flu A
treat with in first 48 hours of symptoms to decrease length and severity
treat all hospitalized or high risk children no matter duration of symptoms
What is the infection control for influenza pandemic
single room with negative pressure
gloves, gown, eye wear and N 95
influenza vaccine
infectious 1 day before symptoms and 1 week after symptoms start
Who really needs to have the influenza vaccine
asthma or chronic lung problem hemodynamically significant cardiac disease immunosuppressive therapy HIV sickle cell or other hemoglobinopathies patients on aspirin therapy chronic renal disease DM spinal chord disorders and neuromuscular disorders pregnancy
What is the vaccine series for influenza
For children less than 9 years old and have never been vaccinated, 2 doses 1 month apart.
If they do not come back for the second dose, they get two doses the next year.
Name the viruses that are in the enterovirus group. When is enterovirus infection most likely to occur and how is it transmitted
coxsackievirus A, coxsackievirus B, echovirus and poliovirus
may to October-when its warm
fecal oral route and person to person transmission
What type of infections can enteroviruses cause?
- coxsackie B serious and fatal disseminated disease in newborns- hepatitis, myocarditis, meningoencephalitis and adrenal cortex failure
- non specific febrile illness
- Hand foot and mouth disease Coxsackie A EV71- fever, vesicles on buccal mucosa, red macular popular rash on hands feet and sometimes the diaper area
- aseptic meningitis, some type particulary E 71 cause of meningoencephalitis that does cause long term sequela. Those with agammaglobulinemia can not clear infection and have recurrent epidodes
- paralytic disease-usually larger muscles groups in lower extremity
- acute hemorrhagic conjunctivitis, subconjunctival hemorrhage, swelling, redness tearing, pain
- herpangina-coxsackie A vesicular or punched out lesions in posterior pharynx
- Bornholm disease: paroxysmal thoracic pain, pleuritic lasts between 4 to 14 days
- myocarditis/pericarditis -coxsackie B or echovirus
How does polio present
aseptic meningitis and or asymmetric flaccid parlysis without reflexes, begins proximally and progresses distally, descending paralysis
What are the symptoms of rotavirus, and when is it the most likely to occur and how is it transmitted
abrupt onset of fever and vomiting followed by watery diarrhea
infection between April to November
fecal oral spread
What are the two vaccines and their schedules for Rotavirus?
RotaTeq- live oral human bovine pentavalent vaccine given at 2,4 and 6 months
Rotarix- live oral human attenuated monovalent vaccine given at 2 and 4 months
What two caliciviruses cause disease what disease symptoms do they cause?
norovirus and sapovirus
Norwalk:
most common cause of outbreaks of gastroenteritis and tend to occur in closed populations (nursing homes, cruise ships, daycares), person to person via fecal oral or contaminated food or water
vomiting, watery diarrhea abdominal cramps
Sapovirus:
acute diarrhea in children
Treatment: supportive care
What are the symptoms of rabies
acute encephalomyelitis with restless ness, excitation and severe spasms of the larynx and pharynx especially when the person sees food or water
How is rabies diagnosed?
Negri bodies (acidophilic inclusion bodies in the cytoplasm of neurons)
animals: virus specific fluorescent antigen in brain tissue (any suspected animal should be euthanized in a way that preserves the brain for appropriate testing)
people: fluorescent microscopy of skin biopsy from the nape of the neck, PCR
Discuss when rabies vaccine is necessary and when an animal can simply be observed
If animal is a pet dog, cat or ferret without evidence of rabies, observe the animal for ten days and if they behave normally, no vaccine is needed
If wild animal (bat, raccoon, skunk, fox, wolf, dog) consider rapid and give RIG and vaccine
Who should get pre-exposure prophylaxis
cave explorers and veterinarians
How is the rabies vaccine given
RIG and vaccine are given as soon as possible
then vaccine is given on day 3, 7, and 14 after 1st dose
What are the symptoms of mumps and when are people contagious
unilateral or bilateral parotitis, sometimes involving the submandibular glands
aseptic meninigitis / encephalitis: usually self limited without sequela
anorexia and abdominal pain
post-pubertal males-eididymoorchitis, usually unilateral
adolescent females-mastitis and oophoritis
1-2 days prior to parotid swelling to 9 days of parotid swelling
What are some complications of mumps and how to you differentiate if from other diseases
hearing loss, usually unilateral and affected recover
no congenital malformation syndrome
check a gram stain of parotid secretions to differentiate it from bacterial (S. aureus) parotitis
another cause of parotitis is frequent vomiting, look for bulemia
What virus causes erythema infectiosum or 5th disease? what are the symptoms
parvovirus B 19
rash with a slapped cheek appearance, lattice-like rash on extremities that is more prominent in the sun or after a warm bath, rash is itchy
in adults causes arthritis in hands, wrists, or knees
What happens if someone with chronic hemolytic anemia or AIDS gets infected with parvovirus B 19
aplastic anemia
What happens in pregnant women with parvovirus B 19 infection
usually infants are normal
however, risk of intra-uterine hydrops and possibly fetal loss
How is parvovirus B 19 diagnosed, treated and what infection precautions are needed
IgM antibodies, PCR in the immunocompromised
supportive care or IvIG in the immunocompromised
once the rash appears in 5th disease child is no longer infectious
those with aplastic anemia are very infectious, negative pressure room with droplet precautions
What are the symptoms of hantavirus
western and southwestern US, deer mouse
severe hemorrhagic pneumonia, thrombocytopenia and increased hematocrit, ARDS
What are the symptoms of dengue fever, dengue hemorrhagic fever?
rapid onset of high fever, sever myalgias and arthralgias, retro orbital pain, severe headache with nausea and vomiting followed by a macular red rash
there is a 2nd rash that looks like measles later with recurrence of fever
Supportive care
What illnesses do BK virus and JC virus cause in the immunocompromised
BK virus causes hemorrhagic cystitis or interstitial nephritis, can cause asymptomatic hematuria in the immunocompetent
JVC- progressive multi-focal leukoencphalopathy
what are the symptoms of new variant CJD?
transmitted from beef
early psychiatric symptoms and late appearing, about 6 months later with ataxia. Once ataxia appears progression to death is quick
How does HIV replicate in the cells
single stranded RNA virus that uses reverse transcriptase to make a DNA strand
structure on lipoprotein envelope attaches to gp 120 on the CD4 cell to gain entry
What part of the immune system does HIV affect, what other organ systems are affected?
CD4 cells which regulate b cells and CD8 suppressor cells
so both b cell and t cell function is lost
also directly infects glial cells causing atrophy and dementia
GI-wasting enteropathy
marrow progenitor cell infection causing anemia and thrombocytopenia
How is HIV transmitted?
sexual contact (vaginal, anal or orogenital)
percutaneous blood exposure
mucous membrane exposure to contaminated blood or other body fluids
mother to child transmission during pregnancy, delivery or breastfeeding
transfusion with contaminated blood products
What should be done to prevent HIV transmission from mother to child?
zidovudine during pregnancy and IV during delivery
C-section before rupture of membranes (each hour of ruptured membranes increases risk of transmission) if viral load > 1000 or if viral load is unknown
no breastfeeding unless formula not available
6 weeks of zidovudine in newborns
if mom did not have any ART, baby gets zidovudine and nevirapine for first week
What are manifestations of HIV in the infant
chronic candidiasis,
parotitis,
persistent generalized lymphadenopathy, hepatosplenomegaly,
fevers,
failure to thrive,
recurrent diarrhea
hepatitis
CNS disease
lymphoid interstitial pneumonia
recurrent invasive bacterial infections, recurrent upper respiratory infections including otitis media or sinusitis, opportunistic infections
20% of those untreated with present 3-6 months with an AIDS defining illness
What CD4 counts indicate severe immune suppression
< 12 months: < 750 CD4
1-5 years < 500 CD4
6 years and up < 200 CD4
How to diagnose HIV in children < 18 months of age
HIV DNA by PCR
3 PCR tests over 4 months
if all 3 are negative and the last one has occurred > 4 months of age child is considered uninfected
How to diagnose HIV in children > 18 months of age
antibody positive with EIA test and then positive with confirmatory western blot
antibody detectable 2-3 months after inoculation, earliest sign if positive HIV DNA by PCR
Name some nucleoside reverse transcriptase inhibitors and what do they do?
inhibit replication of HIV by interfering with the reverse transcriptase enzyme, analogs of normally occurring nucleic acid bases zidovudine (ZDV) didanoside (ddi) zalcitabine (ddc) stavudine (D4T) lamivudine (3tc) emtricitabine (FTC) abacavir
What are the side effects of ziduvudine
bone marrow suppression (anemia, granulocytopenia)
myopathy
What nucleoside reverse transcriptase inhibitors cause pancreatitis and peripheral neuropathy?
didanosine, (ddi) stavudine (d4t), zalcitabine (ddc)
What nucleosidase transcriptase inhibitors do you not give to pregnant women?
ddc and D4t
causes fetal lactic acidosis
what can be a side effect of abacavir
hypersensitivity reaction, usually happens in 4 weeks
rash, flu-like illness
if this happens stop drug and do not ever use again
name a nucleotide reverse transcriptase inhibitor
tenofovir
must be given with a NRTI and a PI or NNRTI
Name two non-nucleosidase reverse transcriptase inhibitors (NNRTI)
nevirapine, efavirenz
NO efavirenz in pregnancy
Name the protease inhibitors. What are some potential side effects of this drug class?
all end in “navir”
saquinavir, ritonavir, indinavir, nelfinavir, amprenavir, fosamprenavir, (not approved for children) lopinavir/ritonavir, atazanavir, darunavir
fat redistribution and lipid abnormalities (increased triglycerides and cholesterol)
for treatment do not use stains
Diabetes
What is a side effect of indinavir
asymptomatic hyperbilirubinemia and nephrolithiasis
Name some integrase inhibitors, (INSTI)
Raltegravir, dolutegravir
How is viral load determined for HIV? What does a viral load prognosticate?
RNA assay determines viral load
it is a good long term predictor of outcome, barring treatment a single RNA viral load can establish prognosis, < 5000 is associated with normal CD4 counts, > 30,000 signals greatly increased risk of progression
What are indications for testing viral load for HIV?
Indications for testing:
syndrome consistent with acute HIV
initial evaluation of newly diagnosed HIV
every 3-4 months for patients both on and not on therapy
2-8 weeks after starting therapy
clinical event or substantial decline in CD4 count
What are the indications to start ART
- Symptomatic (AIDs or significant symptoms)
- All children < 12 months old who have HIV regardless of CD4 count
- minimal or no symptoms,
age 1- < 3 years: CD count < 1000
age 3- < 5 years: CD4 count < 750
age > 5 years CD4 count < 500
When should you consider ART?
Child is asymptomatic and CD4 count is greater than the cutoffs for the ages for indication for treatment
if viral load is > 100,000 this is stronger evidence for initiating treatment.
patient and family have to be willing to adhere to therapy
What drug combinations for HIV treatment is recommended by the CDC
1 of: efavirenz, nevirapine or lopinavir plus ritonavir
and one of the following four sets
1. abacavir plus lamivudine or emtricitabine
2. ddi plus emtricitabine
3. tenofovir plus lamivudine or emtricitabine (must be tanner 4 or greater)
4. zdv plus lamivudine or emtricitabine
When should HIV therapy be changed?
- not tolerating therapy
- viral load not responding (get two to make sure it’s real)
How do you know its not responding?
therapy has not suppressed viral load to < 50 in 4-6 months, an increase > 3 fold from prior nadir, previously undetectable levels now more than 5000-10000.
When is post-exposure prophylaxis recommended and what is it?
blood or bloody body fluid that was either percutaneous, mucous membranes or compromised skin.
Not for urine source exposures
zdz, 3tc +/- lopinavir/ritonavir
what are the vaccine recommendations for children with HIV?
They should get all of their recommended vaccines.
The not live vaccines can be given according to schedule
for MMRV can be given if CD4 count is good (greater than 15% in 1-5 year olds)
Rota virus can be given regardless of CD4 counts or known HIV status
PPSV23 at 24 months, given at least 8 weeks after last PCV13.
Flu annually
Describe acute retroviral syndrome
flu or mono like illness 2-4 weeks after infection and lasts for 1-2 weeks
fever, lymphadenopathy, pharyngitis. rash (maculopapular, on face, trunk and extremities including palms and soles), mucocutaneous lesions, myalgias
Name some signs of HIV
persistent or recurrent seborrheic dermatitis
tenia infections. psoriasis, molluscum contagiosum, folliculitis and mucocutaneous infections like herpes, candidiasis. Older child with chronic ear infections
What is immune reconstitution inflammatory syndrome?
inflammatory disorders associated with a paradoxical worsening or pre-existing infectious processes following initiation of ART.
examples of infection include: MAC, CMV, hepatitis B, herpes, pneumocystis.
Usually self limited, a specialist may consider steroids
How does PCP present in an infant?
2-6 months of age. insidious onset with cough and mild tachypnea with no fever
over 1-4 weeks progresses to diffuse bilateral interstitial plasma cell pneumonitis with cyanosis and retractions
How does PCP present in an older child or adolescent
insidious onset of fever, shortness of breath and dry cough.
usually hypoxic with a wide A-a gradient
Who should get PCP prophylaxis
all perinatally HIV exposed infants from 4-6 weeks until not proven to be infected
all HIV infected asymptomatic children < 1 year
HIV infected age 1-5 with CD4 < 500
HIV infected 6-12 if CD4 < 200
history of PCP, gets life long prophylaxis
How is PCP diagnosed and treated
methenamine silver stain or PCR from BAL samples mild PCP with oral TMP/SMX or atovaquone Severe PCP (PaO2< 70 or A-a gradient > 35): IV TMP/SMX, or IV pentamidine and high dose steroids
What side effects are associated with some of the medications used to treat PCP?
TMP/SMX: neutropenia
Pentamidine: recurrent doses damage islet cells and can cause hypoglycemia or hyperglycemia
What are some regimens for PCP prophylaxis
TMP/SMX (preferred)
dapsone
pentamidine either aerosolized or IV
TMP/SMX is preferred because it treats extrapulmonary PCP, if more effective and also prophy against toxo
What are the criteria to diagnose endocarditis?
2 major criteria
1 major and 3 minor
or 5 minor
Major criteria: positive blood culture, echo suggesting infection
Minor criteria:
predisposing conditions (valve disease or IV drug use)
fever
vascular phenomenon (janeway lesions, emoboli)
Immunologic phenomena (acute glomerulonephritis, osler nodes, roths spots, + RF)
positive blood culture that does not meet major criteria
What are indications for surgery for endocarditis?
fistula, abscess, pericarditis, embolic disease or persistent fever or valve disease results in ventricular failure
Who is most susceptible to endocarditis?
Children with known heart defect
What organisms cause endocarditis
strep viridans (40%), staph aureus (20-30%), coagulase negative staph (5%) in prosthetic valves up to 1 year after surgery, staph epidermidis
How does endocarditis normally present in a child?
Fever, splenomegaly and heart murmur
What are janeway lesions
nontender macules on the palms and soles
with staph can see peripheral eccymoses
What are osler’s nodes
tender nodules on the palms, fingertips and soles
What are roth spots
pale retinal lesions surrounded by hemorrhage
What is the treatment of endocarditis
Penicillin sensitive streptococcus: 2 weeks of PNC G or ampicillin and gentamycin or 4 weeks ampicillin / ceftriaxone
Streptococcus: penicillin G or ampicillin and gentamycin 4 weeks
MSSA: oxacillin or cefazolin for 6 weeks
MRSA: especially if prosthetic valve, vancomycin, rifampin and gentamycin for 2 weeks then vancomycin and rifampin for 4 weeks
What organisms cause meningitis for neonates, children and adolescents?
< 1 month : group B strep, gram negatives and listeria
> 3 months to 10 months: S. pneumoniae
10-19 years : neisseria
What is the empiric treatment for meningitis?
Ceftriaxone and vancomycin (for resistant pneumococcus) : children > 3 months
For infants: ceftriaxone, vancomycin and ampicillin if less than 1 month use cefotaxime as it does not worsen hyperbilirubinemia
What is the empiric treatment for a brain abscess
ceftriaxone, vancomycin and metronidazole
When should a stool sample be obtained in a patient with diarrhea
febrile with bloody or mucous stools, immunocompromised, prolonged symptoms, epidemic outbreaks and travel
