Infectious Disease Flashcards
What is the most likely diagnosis for pt presenting with postauricular and suboccipital lymphadenopathy, small pinkish red spots on the soft palate, joint pain and swelling, and discrete pinkish red macular lesions starting on face and spreading distally?
Rubella
Forchheimer spots- pinkish red spots on soft palate
what are the two most common pathogens that cause secondary bacterial infection in pt with Influenza?
- S. aureus
2. Strep pneumoniae
What is the most likely diagnosis of newborn presenting with IUGR, hydrocephalus, microphthalmia, chorioretinitis, hepatosplenomegaly, rash, generalized lymphadenopathy, and generalized cerebral calcifications?
Toxoplasma gondii infection
pregnant mom changing cat litter
what is the treatment to eliminate or diminish MRSA carrying status?
Topical mupirocin in anterior nares BID fro 5 days
What is the most likely diagnosis of pt presenting with small irregular, red spots with bluish white center on buccal mucosa, fever, cough, coryza, conjunctivitis, and confluent erythematous macular rash over the trunk?
Measles (Rubeola)
Koplik spots- redspots with bluish center on buccal mucosa
What is the timeframe for maternal varicella infection that results in severe/ fatal varicella?
2-5 days prior to delivery
infants should receive varicella-zoster IgG
what is the most likely diagnosis for pt presenting with symmetrically distributed, flesh toned to brownish, papules on face, buttocks, and extensor surface of knees and elbows, sparing the trunk, that are flat and without umbilication, and may have associated axiallary/ inguinal lymphadenopathy and hepatosplenomegaly?
Gianotti-Crosti syndrome
(papular acrodermatitis of childhood)
(due to EBV infection)
What two sports are associated with herpes gladiatorum (grouped tender vesicles that ulcerate, erode, and crust localized to abraded area of skin)?
- Wrestlers
2. Rugby
What is the best treatment for malaria prophylaxis for pt traveling to area with chloroquine resistance? (3)
- Doxycycline (1-2 days prior, daily until 4 weeks after)
(avoid prolonged sun exposure, children less than 8) - Malarone (atovaquone/ proguanil) for 1-2 days before, daily until 7 days after)
- Mefloquine (weekly, 1 week before and 4 eks after)
What is the most likely diagnosis for pt presenting with exudative pharyngitis, nonpurulent conjunctivitis, rhinitis, hemorrhagic cystitis, and preauricular and anterior cervical lymphadenopathy in warmer months?
Adenovirus
tx: cidofovir for immunocompromised pt
What is the most likely diagnosis for pt presenting with exudative hemorrhagic lesions of retina, shortness or breath, fatigue, joint pain, malaise, tender pea sized intradermal nodules on finger pads, nonblanching linear brownish red lesion under nail bed, and painless macular blanching erythematous lesion on palms and soles in the setting of cardiac defect and recent dental procedure?
Subacute bacterial endocarditis
Roth spots, Osler nodes, Splinter hemorrhages, Janeway lesions
What is the most likely diagnosis for pt presenting with pruritic fine pinkish red papular rash on face, trunk, and extremities that spares circumoral area/ palms/ soles and feels like gooseflesh/ sandpaper, linear petechiae in flexor surfaces, headache, GI upset and sore throat?
Scarlet fever
Pastia lines
What is the most likely diagnosis for pt presenting with headache, malaise, myalgia, photophobia, erythematous macules and petechiae around ankles, wrists, palms and soles sprading centrallyand hyponatremia?
Rocky Mountain Spotted Fever
What is considered a positive tuberculin test in child under 4 years old, from high TB areas, in close contact with high risk population or have chronic medical conditions?
more than 10 mm
What is the most likely diagnosis for pt presenting with regional lymphadenopathy, painful red ulcer at site, sudden fever, hepatosplenomegaly in the setting of being a hunter?
Tularemia
francisella tularensis from rabbits
what is the most likely diagnosis for pt presenting with firm, discrete, nontender nodes unilaterally on the neck after traveling out of the country?
Cervical tuberculous lymphadenitis (Scrofula)
dx: surgical excision and biopsy
(tx 9 months of therapy)
What is the most common long term complication of bacterial meningitis?
hearing loss
What disorder is associated with a radiographic finding of osteochondritis at the metaphyses and periostitis of the bone in a newborn?
Congenital syphillus
due to treponema pallidum
What is the most likely diagnosis for a pt presenting with erythematous, wet appearing rashh with peripheral crusting within the intertriginous areas (web of finger)?
Cutaneous candidal infection
tx: topical clotrimazole or nystatin
What is the most likely diagnosis for pt presenting with intensely red facial rash associated with circumoral pallor and a symmetric maculopapular lattice like rash on the extremities with associated prodrome of headache, fever, coryza, diarrhea?
Erythema infectiosum due to Parvovirus B19
can result in red blood cell aplasia and severe anemia in sickle cell pt
What infection is commonly associated with uncooked hot dogs and goat cheese?
Listeria
what is the best initial treatment for bacterial meningitis?
Ceftriaxone and vancomycin
When can a child with active varicella infection return to school/ daycarre?
when all lesions are dried and crusted over
contagious 1-2 days prior to rash
What is the most likely diagnosis for pt presenting with chronically draining lesion in the setting of water exposure (swimming pool, fish tank)?
Mycobacterium mariunum
What is the best treatment for pt with severe otitis externa?
Ciprofloxacin PO
What is the most likely diagnosis for pt with progressive hoarseness, intermittent inspiratory stridor, and vocal cord lesion?
Juvenile Larygneal papillomatosis
due to HPV (human papillomavirus)
What is the most likely diagnosis for pt presenting with facial nerve palsy (bell’s palsy- inability to smile or close eye) and complete heart block?
Early disseminated Lyme disease
ELISA for Borrelia burgdorferi IgG and IgM
What is the treatment for rocky mountain spotted fever?
Doxycycline
What is the electrolyte abnormality associated with Rocky Mountain spotted fever?
hyponatremia
What is the most likely diagnosis for an infant with hypoxia, tachypnea, bilateral interstitial infiltrates in the setting of mother with no prenatal care?
Pneumocytis jiroveci (PCP) due to AIDS
tx: steroids and Bactrim
What prenatal infection results in fetal ultrasound showing subcutaneous edema, pleural effusion, pericardial effusion, ascites, and fluid accumulation of major organs, and anemia?
Parvovirus B19
What is the most likely diagnosis for infant presenting with staccato like cough, nasal congestion, rales in absence of wheezing and peripheral eosinophilia?
Chlamydia trachomatis pneumonia
What vitamin deficiency is associated with the treatment with Isoniazid?
Pyridoxine (vitamin B6)
results in peripheral neuropathy
True or false. Perceptual distortions can be presenting symptom of infectious mononucleosis?
True
What is the best initial treatment for neonate with Listeria sepsis?
Ampicillin and gentamicin
What is the most likely cause for pt presenting with fever, anorexia, fatigue, exudative pharyngitis, cervical lymphadenopathy, and negative EBV titers?
CMV (cytomegalovirus)
What is the next best step in management if there are 2 or more cases of invasive HiB infection?
all attendees and workers at a given child care should receive rifampin prophylaxis
Which patients should received measles immunoglobulin via IV in the setting of close measles exposure? (3)
- HIV pts with severe immunosuppression
(regardless of vaccine hx) - less than 1 year old
- pregnant
What is the best treatment for Tularemia?
Gentamicin or Streptomycin
What is the most likely diagnosis for pt presenting with discrete vesicles surrounded by erythema, some of which are ulcerated, on the posterior pharyngeal wall/ uvula/ anterior tonsillar pillar in setting of sudden fever?
Herpangina
due to Coxsackie
What disease is associated with epidemic keratoconjunctivitis (with crusting) and swimming pools?
Adenovirus
What is the treatment for 1st recurrence and 2nd recurrence of C. difficile?
1st: repeat metronidazole
2: oral vancomycin
When can a pt return to work/ school if they have a herpes zoster infection?
immediately as long as lesions are covered
What is the most likely diagnosis for pt presenting with acute rapidly progressive symmetric erythematous swelling of hands and feet that is sharply demarcated at the wrists and ankles, along with painful papules, petechiae adn purpura?
Papular purpuric gloves and socks syndrome
due to Parvovirus B19
Which disease is a vaccine preventable disease for which herd immunity is not a factor?
Tetanus
What is the most likely diagnosis for pt presenting with painful swelling at tips of fingers with fluid-filled blister located at fat pad of fingers in the setting of history of eczema?
Blistering distal dactylitis
due to Group A strep
What bacteria that causes gastroenteritis can also cause purulent vaginal discharge that may be blood tinged?
Shigella
What are the lab findings associated with whooping cough (Bordetella pertussis)? (2)
- Lymphocytosis
2. Thrombocytosis
What treatment for tuberculosis can result in orange colored secretions and urine?
Rifampin
What is the most likely diagnosis for pt presenting with severe ear pain, facial nerve paralysis (inability to close eye, smile, wrinkle forehead) and red vesicles in the external ear car?
Ramsay Hunt
(due to varicella zoster virus)
(tx: acyclovir and steroids)
What test can be used to distinguish latent TB from tuberculin skin testing positive due to BCG vaccination?
Interferon gamma release assay
should do TST testing initially
What is the best diagnositic tool for early diagnosis of osteomyelitis?
MRI
can use Xray after 10-14 days
What is the most likely diagnosis for pt with penetrating eye injury with ring abscess formation in the cornea?
Bacillus cereus
What is the most likely diagnosis for pt presenting with serpiginous, migratory well demarcated plaques that are pruritic after spending time in Florida/ Caribbean/ Mexico?
Dog hookworms
tx: oral abendazole or ivermectin
What are the inpatient isolation requirements for measles infection (airborne)?
standard precautions
private, negative pressure ventilation
N95 respirators at all time
What is the treatment for close contact prophylaxis for meningococcal disease? (3)
- Rifampin BID for 2 days
- IM ceftriaxone x 1
- Ciprofloxacin x1
(one time treatment preferred)
what 3 maternal viral infections are contraindications to breastfeeding?
- HIV
- HTLV-1
- HTLV-2
what is a potential complication of suppurative thrombophelbitis of the jugular vein (lemierre disease)?
Septic emboli to lungs
what is the most likely diagnosis for pt presenting with tick bite in Arkansas associated with pancytopenia and elevated transaminases?
Ehrlichiosis
what is the most likely diagnosis for newborn (3-4 weeks old) presenting with facial cellulitis, pre/post auricular lymphadenopathy, submandibular cellulitis, poor feeding, and irritability?
Late onset Group B strep infection
What is the most common cause of discitis (fever, malaise, localized back pain, limp, decreased deep tendon reflex, and disc space narrowing?
S. aureus
What is the treatment for group A strep toxic shock syndrome?
Penicillin G and clindamycin
What is the treatment for E. coli O157:H7?
supportive care and IV hydration
antibiotics may increase risk of HUS
What is the best treatment for mother and infant in the situation where newborn was born to mother with positive PPD but negative CXR?
treat mother with INH (isoniazid)
What is the most likely cause of meningits with brain abscess formation?
Citrobacter koseri
What is the most common cardiac abnormality associated with congenital rubella syndrome?
Patent ductus arterosus
(machine like continuous murmur heard best at left infraclavicular area, radiates to back and has associated thrill at 2nd intercostal space)
What meningococcal vaccine can be given to children younger than 2 years of age who are high risk?
- Menveo (MenACWY-CRM) starting at 2mo, 4mo, 6mo, and 12mo
2. MenHibrix (Hib-MenCY-TT) given as early as 6 weeks old
What is the most likely diagnosis for pt presenting with bulging fontanel, postauricular and occipital lymphadenopathy, irritability, exanthem of red papules located on soft palate, and blanching macular/ maculopapular lesions begin on neck and trunk and spread to face and extremities as 3day of fever abates?
Roseola infantum (due to HHV-6)
What is the most common clinical manifestation of late Listerosis (after 1 week of age)?
Meningitis
Sepsis and pneumonia are more common for early Listeria
What is the most common complication of mumps in males?
Epididymo-orchitis
fever, severe testicular pain and swelling
What are the recommendations for return to daycare (in setting of pregnant teacher) for children diagnosed with Fifth disease (erythema infectiosum)?
Can return immediately
What is the most likely diagnosis if pt presents with biopsy/pus with sulfur granules and gram stain showing beaded, branching, gram positive bacilli?
Actinomyces israelli
tx IV penicillin or ampicillin for 4-6 weeks followed by oral for 6-12 months
What is the most likely diagnosis for pt presenting with blood culture positive for gram positive diphtheroid like organism?
Listeria
tx with ampicillin or penicillin
What is the best treatment for group C streptococcal infection?
Penicillin G
What immunologic deficiency as increased risk for Neisseria meningitides infection?
Terminal complement component deficiency (C5-C9)
What is the most likely diagnosis for pt presenting with fever, altered mental status, bizarre behavior and focal lesions in the temporal lobe on imaging?
Herpes simplex meningoencephalitis
What is the most common cause of osteomyelitis in sickle cell patients?
Salmonella infection
What is the best step in management for pt suspected to have epiglottis?
- call for immediate ENT/ anesthesia consult to protect airway
- start IV Ceftriaxone and Vanc
What is the next best step in management of a newborn who is exposed to a family member with active pertussis infection?
Azithromycin 10 mg/kg x 5 days
What is the most likely diagnosis for pt with positive strep infection experiencing worsening OCD/ tic disorder/ choreiform movements?
PANDAS
pediatric autoimmune psychiatric disorder associated with streptococcal infections
What test is used for detection of acute EBV?
IgM to EBV viral capsid antigen
What is the most common cause of infectious congenital sensorineural hearing loss?
CMV
What is the most likely diagnosis for newborn presenting with neonatal sepsis, elevated monocytes, and maternal history of flu like illness during 2nd or 3rd trimester?
Listeria infection
What is the most likely diagnosis for pt presenting with pharnygitis with exudate, cervical lymphadenopathy, maculopapular rash and gram positive rod that only grows on blood enriched media?
Arcanobacterium haemolyticum
What is the most appropriate step in management of pt with Influenza and history of asthma?
Treat with tamiflu (even if after 48 hours as it can reduce transmission)
What is the most likely diagnosis for pt presenting with watery, nonbloody diarrhea after a trip to the water park and stool culture showing small rounded oocsyts?
Cryptosporidium
What is the best treatment for cryptosporidium (profuse watery diarrhea with oocytes in stool)?
Nitazoxanide
What is the most likely diagnosis for infant with worsening diaper rash with reddish- purple nodules in the diaper area that look neoplastic but are not?
Granuloma gluteale infantum
due to secondary Candida albicans infection
What is the most likely diagnosis for pt presenting with pain when applying downward force on knee an contralateral hip while the knee and ipsilateral hip are flexed, with the ipsilateral hip abducted and externally rotated so ipsilateral ankle is over contralateral knee?
Septic arthritis of sacroiliac joint
FABER test
What is the most likely diagnosis for pt presenting with well circumscribed tender erythematous perianal eruptions and painful bowel movements?
Perianal streptococcal infection
Tx: penicillin/ amoxicillin
what is a once daily antimicrobial regimen for step pharyngitis?
Amoxicillin 50 mg/kg daily for 10 days
What is the most likely diagnosis for pt presenting with fever, persistent cough, bilateral crackles and wheezing at lung base, hepatomegaly, eosinophilia, and CXR showing bilateral peribronchial infiltrates in setting of having a dog exposure?
Toxocara canis
more common in child with PICA
What is the best treatment for an Enteroccous UTI?
Ampicillin
cephalosporins are ineffective
what OTC medication should be avoided for at least 6 weeks after varicella vaccine/ infection or influenza infection?
NSAIDs or NSAID containing medications
what is the most likely diagnosis for pt presenting with fever, chills, myalgias, arthralgias, and giemsa stained blood showing intraerthrocytic and exoerythrocytic organisms in setting of being immunocompromised (asplenic) and living in northeastern or upper midwest?
Babesia microti
What is the most likely cause of osteomyelitis located in the calcaneus region?
Pseudomonas aeruginosa
What is the most common cause of aseptic meningitis?
Enterovirus
Arbovirus is most common cause of encephalitis or meningoencephalitis
What is a potential complication of treatment of Pertussis?
Pyloric stenosis
due to erythromycin treatment
What is the best treatment for a neonate born to a mother with untreated gonorrhea?
IM Ceftriaxone 125 mg
ophthalmic ointment not good enough
what is the best initial treatment for Lyme disease?
Doxycycline 100 mg BID for 28 days
if not improved, can repeat followed by Iv ceftriaxone for 28 days
What is the most likely diagnosis for pt presenting with rubbery cervical lymph node that increases in size despite antibiotics and has reddish- purple discoloration over overlying skin?
Mycobacterium avium-intracellular
What is the treatment for rabies prophylaxis?
- cleanse wound
- Rabies Ig
- 4 dose series with human diploid cell or purified chick embryo cell vaccine
What is the best treatment for pt presenting with Parinaud oculoglandular syndrome (conjunctivitis with granulomatous lesion and preauricular lymph node)?
Azithromycin
Due to Bartonella henselae
What is the most likely diagnosis for pt presenting with tender, grouped vesicles overlying a red, swollen and tense base on a finger, sometimes associated with discrete gingival ulcers?
Herpetic whitlow
tx: acyclovir
What is the most likely diagnosis for newborn presenting with severe malformation of lower extremities (scarring following dermatome) and microphthalmia/ catarcts/ optic atrophy/ chorioretinitis?
Congenital varicella syndrome
What is the most common cause of juvenile recurrent respiratory papillomatosis?
HPV
What is the diagnosis and treatment for a patient presenting with intensely pruritic rash described as raised papules with raised non-linear, bullous, reddish-brown tracks extending several inches along adjacent skin?
Cutaneous Larva Migrans ; tx w/ albendazole or ivermectin
due to hook warm
What test is performed when you flex the hip and knee with abduction and external rotation of the hip such that the ankle of ipsilateral leg is atop opposite knee in figure 4 position?
FABER test (for septic arthritis of sacroiliac joint)
What ophthalmologic finding is associated with bacterial endocarditis?
Roth spots (exudative hemorrhagic lesions of the retina)
What is the best initial step in management of newborn (unvaccinated infant) who is exposed to a close contact positive for pertussis?
Administer Azithromycin (macrolide)
- IVIG expensive
- vaccine too slow
- not in breastmilk
What is the best management for an asymptomatic newborn born to a mother positive for untreated gonorrhea?
IM ceftriaxone
-erythromycin ointment not sufficient
What is a possible complication associated with the administration of oral macrolide in infant?
Pyloric stenosis
consider in pt diagnosed with pertussis and being treated
What is the difference between neonatal infection with CMV versus Toxoplasmosis?
CMV- periventricular calcifications
Toxoplasmosis- generalized intracranial calcifications
What is the most likely bacterial cause of bloody vaginal discharge along with GI symptoms (watery diarrhea, bloating, vomiting)?
Shigella
What is the time frame for severe/ fatal varicella infection for newborn if mother has active infection?
if mother infected 5 days prior to 2 days after delivery
what is the treatment of choice for patient with Tularemia?
Gentimicin or Streptomyin
What is the likely diagnosis for patient presenting with ulcerative eschar and unilateral lymphadenopathy in setting of fever, malaise, and possible hepatosplenomegaly?
Tuleremia
rabbit exposure
What is the next best step in management for patient who is immunocompromised and has recent measles exposure?
IVIG (regardless of vaccine history or serology)
within 6 days of exposure
What is the most common bacterial cause of brain abscess with CSF findings of elevated WBCs, elevated protein and low glucose?
Citrobacter
What is the most likely diagnosis for patient presenting with acute bell’s palsy and complete heart block?
Lyme disease (disseminated)
What is the next best step if there is 2 or more cases of Hib infection in a daycare/ school setting?
all attendees and teachers should receive Rifampin prophylaxis regardless of vaccination status
(decrease carrier status)
what is a common lab finding in patients with Rocky Mountain Spotted Fever?
Hyponatremia
What is the best treatment for group C streptococcal pharyngitis?
penicillin
What is the most likely diagnosis for patient presenting with complaints of perceptual distortions (distorted shapes, sizes, colors and/ or spatial relationships)?
Infectious Mononucleosis
Alice in Wonderland effect
What is the best treatment option for patient with severe otitis externa especially when immunocompromised?
Ciprofloxacin
pseudomonal coverage
What is the most likely diagnosis for a patient presenting with rubbery node slowly increasing in size acquiring a reddish-purple discoloration and resistant to typical antibiotics?
Mycobacterium aviam- intracellulare
tx: excision
What is the most likely diagnosis for a 3-4 week infant presenting with bacteremia and focal infection (meningitis, cellulitis, septic arthritis, osteomyelitis, or adenitis)?
Late onset Group B Strep
(strep. agalactiae
What is the most common presentation of early onset GBS infection of neonate?
Septicemia
What is the most likely diagnosis for a neonate with increased peripheral monocytes, CSF consistent with bacterial meningitis and mother’s history of flu-like illness during 2nd o 3rd trimester?
Listeria
What is the rabies prophylaxis treatment recommendation for bite/ scratch/ mucous membrane contact with potential rabid animal (i.e. bat)? (3)
- throughly clean wound
- 1 dose of rabies immunogloblin
- 4 dose series of human diploid cell/ chick embryo vaccine
What is a possible GU complication in males associated with mumps?
Orchitis
firm, tender swollen testicle 4 -7 days after parotitis
What is the best initial treatment for lyme arthritis?
Doxycycline 100 mg for 28 days
if fail, can repeat doxycycline or IV ceftriaxone for 28 days
When is a child consider non-infectious if they have Parvovirus (fifth disease)?
once the rash appears
What is the most likely diagnosis for patient presenting with papular, flesh toned, flat rash symmetrical distributed and mainly on face, buttocks and extensor surfaces sparing trunk?
Gianotti- Crosti syndrome
due to EBV mostly
What is the most likely diagnosis for immunocompromised or asplenic patient presenting with flu like illness, hemolytic anemia, thrombocytopenia, elevated BUN and intraerythrocytic and exoerythrocytic organism on Giemsa stain?
Babesia
occurs in similar locations as Lyme disease- Northeast
What is the most likely diagnosis for patient (with history of eczema) presenting with single large blister (bullae) with surrounding erythema and painful swelling of the volar at pads of his finger?
Blistering distal Dactylitis
due to group A Strep or S.aureus
What is the most likely diagnosis for a patient presenting with chronically draining lesions with history of repeat water exposure?
Mycobacterium marinum
What is a common laboratory finding associated with Pertussis infection?
elevated WBCs with lymphocytosis
What is the most likely diagnosis for neonate who is born with significant limb abnormalities (scarring in zig-zag pattern, shortened) and microopthalmia if mother had no prenatal care?
Varicella embryopathy
