Infectious Disease Flashcards
What is the most likely diagnosis for patient presenting with recurrent wheezing, worsening hoarseness, then develops stridor, and has Xray showing soft tissues lesion on vocal cords without subglottic narrowing?
Juvenile laryngeal papillomatosis
(due to HPV 6 or 11)
(dx: direct laryngoscopy & biopsy)
(tx: surgery)
What is the most likely diagnosis for male pt presenting with orchitis (testicular pain, fever, indurated red swollen testicle with normal ultrasound), fatigue and facial swelling that obscures the mandible?
Mumps
parotid enlargement occurs
… are tender small intradermal nodules in the pads of fingers, palms and soles that are associated with ….
Osler nodes; subacute bacterial endocarditis (SBE)
What empiric antibiotics should be used for sepsis in a 3 week old or less infant?
IV cefotixin and IV ampicillin
ceftriaxone causes biliary sludging
What is a late complication of untreated lyme disease?
Arthritis
What is the treatment for early disseminated lyme disease?
Doxycycline (if older than 8 years old) or Amoxicillin (if younger than 8) for 14-21 days
What is the most likely diagnosis and treatment for pt presenting with pruritic papules on lower extremities described as raised, non-linear, bullous, reddish brown, serpiginous tracks?
Cutaneous Larva Migrans (Hookworm); Abendazole/ Ivermectin
common in tropics and southeast America
What is the definitive treatment for streptococcal toxic shock syndrome?
Penicillin G with clindamycin
What is the likely cause of peripheral neuropathy symptoms in a patient who was treated for TB?
Isoniazid
depletes pyridoxine
What is the most likely diagnosis of patient in Arkansas presenting with pancytopenia, elevated transaminases, fever, truncal rash after tick bite?
Ehrlichiosis
… are exudative, edmeatous, hemorrhagic lesions on the retina associated with …
Roth spots; subacute bacterial endocarditis (SBE)
What is the most likely diagnosis in a child less than 5 years old who presents with low grade fever, back pain, irritability, refusal to walk, tenderness over lumbar region with paraspinal muscle spasm, normal WBC, elevated ESR/ CRP, and MRI showing narrowing of intervertebral disc space?
Discitis
tx: can resolve w/out antibiotics; but should treat with antibiotics
… test is when there is pain with flexion of hip and knee with abduction and external rotation of hip with ankle of ipsilateral leg on top of opposite knee suggests ….
Faber; septic arthritis of sacroiliac joint
What is the likely diagnosis and appropriate immediate management of pt presenting with acute onset fever, severe sore throat, drooling, raspy voice, stridor and learning forward in respiratory distress?
Epiglottis; immediate consult of ENT/ anesthesia and IV ceftriaxone and vancomycin
What is the treatment of choice for C. diff?
Metronidazole (Flagyl)
What is the most likely etiology of an intensely erythematous facial rash associated circumoral pallor and symmetric, maculopapular lattice like rash on extremeities in a sickle cell patient?
Parvovius B19
5th disease, slapped cheek
What is the pathophysiology cause of chronic mucocutaneous candidiasis?
T cell dysfunction
What is the treatment for non-TB mycobacterial lymph node infection?
Surgical excision and biopsy of lymph node
What is the next step in management for a child under 4 years old who was exposed to individual with active TB but patient’s initial PPD was negative?
Start Latent TB treatment and obtain CXR (high risk of disseminated disease in age group); repeat test in 10-12 weeks
What is the most likely diagnosis for a child presenting with flesh colored papules without umbilication in symmetric pattern mainly located on face, buttocks and extensor surfaces of hands and knees sparing trunk and associated fatigue?
Gianotti-Crosti syndrome (aka papular acrodermatitis of childhood)
(due to EBV)
What is the most common location for non-TB mycobacterium lymphadenopathy?
submandibular
A patient presenting with non-purulent conjunctivitis, exudative pharyngitis and preauricular lymphadenopathy along with fatigue most likely suffers from…
Adenovirus
What is the leading infectious cause of sensorinerual hearing loss?
CMV
What is the most likely etiology for a patient presenting with fever, rigors, dysphagia, trismus, decreased range of motion of neck, tonsillar swelling with uvula midline and tenderness/ swelling/ induration over neck?
Lemierre Disease
What is a complication of Lemierre Disease?
septic emboli (to lungs)
What is the management step for a patient who has history of Redman Syndrome but is in need of Vancomycin?
- premedicate with Benadryl
2. slow infusion of vancomycin over 4 hours
What is the recommended chemoprophylaxis indicated for close contacts of a patient with meningococcal meningitis? (3)
- Ciprofloxacin 500 mg once
- Rifampin 10 mg/kg (max 600 mg) BID for 2 days
- IM ceftriaxone (125 if less than 15 years old or 250 if older)
What is the most likely cause of fever, exudative pharyngitis, lymphadenopathy, scarlatinaform rash that does not desquamate and no strawberry tongue or palatal petechiae?
Arcanobacterium haemolyticum
What is the treatment for Arcanobacterium haemolyticum?
Erythromycin
A newborn with vesicles on erythematous base at various sites of entry and MRI showing focal edema and hemorrhagic necrosis most notably in temporal lobes suffers from…
Neonatal Herpes
What is the most common bacteria to cause discitis?
S. aureus
What is the most common bacteria to cause retropharyngeal abscess?
Strep. pyogenese
What is the most likely diagnosis for patient presenting with acute pain, difficulty swallowing, inspiratory stridor, and neck Xray showing prevertebral soft tissue swelling that displaces trachea forward?
Retropharyngeal abscess
What is the most likely diagnosis for patient presenting with erythematous macular rash that progresses to large superficial blisters leaving behind desquamating tender erythematous skin and associated fever?
Staph Scalded Skin Syndrome
tx with vancomycin
What infection causes herpangina?
Coxsackie virus
When can a child return to school/ daycare with active chicken pox infection?
when all lesions have crusted over
infectious for 1-2 days prior to rash and until lesion crusting
When can a patient return to school/ work if have shingles (herpes zoster)?
immediately as long as can cover lesions
only spread via direct contact
What is the treatment for Parinaud oculogranduolar syndrome (red itchy eye in setting of fever, fatigue, lymphadenopathy, necrotizing granuloma of lymph node and cat scratches)?
No treatment needed
(can use Azithromycin)
(due to Bartonella henselae)
What is the most likely diagnosis for patient presenting with periorbital and eyelid edema, fever, exudative pharyngitis, cervical lymphadenopathy, morbilliform rash and petechial lesions on soft and hard palate?
EBV
What is the most likely diagnosis of patient presenting with fluid filled tense blister with surrounding erythema on volar fat pad of fingers (not in clusters)?
Blistering distal dactylitis
due to group A strep
what is the most likely diagnosis in a less than 2 year old with unknown maternal birth history who presents with reddish pink papulosquamous lesions on back/butt/thighs/soles with associated mucocutaneous lesions, hepatosplenomegaly, jaundice, lymphadenopathy, osteochondritis/ periostitis of bones (associated with irritability and refusal to move limb) and hemorrhagic rhinitis (snuffles)?
Congenital Syphilis
tx: penicillin G
What is the most likely cause of osteomyelitis (superficial and deep soft tissue swelling over radiolucent lesion of bone) after stepping on nail?
Pseudomonas aeruginosa
what is the most likely diagnosis for a younger child with fever and maculopapular and vesicular lesions on palms and soles with ulceration of soft palate and anterior tonsillar pillars?
Hand Foot and Mouth
due to Coxsackie A16 virus
What is the most likely diagnosis for a patient with respiratory symptoms (wheezing, non-productive cough, SOB), hepatomegaly, eosinophilia and bilateral peribronchial infiltrates on Xray after playing with dog?
Toxocara canis (dog hookworm from dog feces)
What is the most likely cause of fever, vomiting, bloody diarrhea, anemia, fragmented RBCs and burr cells on peripheral smear after eating undercooked meat?
Hemolytic Uremic Syndrome (HUS) due to shig toxin producing E.Coli
What is the most likely diagnosis for patient presenting with history of 3 days of fever that resolved and then develop erythematous blanching macules that start on trunk and spread distally with associated palpebral and periorbital edema?
Roseola
can be associated with bulging fontanel
What is the most likely diagnosis for patient in the northeast/ upper midwest presenting with fever and flu-like symptoms in the setting of intraerythrocytic and extraerythrocytic parasites on Giemsa stain forming a Maltese cross?
Babesia
What is the primary reservoir and primary transmitting vector for Babesia?
reservoir- white footed mouse
vector- Deer tick
… are non-blanching, linear, reddish brown lesions under the nail bed that are associated with subacute bacterial endocarditis
Splinter Hemorrhage
… are macular, blanching, erythematous lesions on palms and soles associated with subacute bacterial endocarditis
Janeway lesions
What is the purpose of the double disc diffusion test and what diagnosis is it used for?
tests for inducible resistance to clindamycin; MRSA
What is the most common laboratory finding associated with whooping cough (Bordetella pertussis)?
lymphocytosis
What is the cause for Roseola?
Human herpesvirus 6
What is the treatment of choice for dog/ cat bite prophylaxis in patient who has penicillin/ amoxicillin allergy?
Bactrim plus clindamycin
1st choice if no allergy is Augmentin
What are 3 indications for Hib chemoprophylaxis for household members of a Hib positive patient?
- presence of infant less than 12 months who has not completed vaccination
- immunocompromised household member
- presence of kids under 4 years old who have not completed vaccination
What is the most likely diagnosis for a 4-5 year old boy with history of constipation who presents with well circumscribed, tender, erythematous perianal eruption sometimes associated with pseudomembrane?
Streptococcal perianal dermatitis
What is the most likely diagnosis for a pt presenting with bloody or serosanguineous vaginal discharge with recent history of diarrhea, abdominal pain, and fever?
Shigella flexneri
tx: penicillin/bactrim
What is the preferred postexposure prophylaxis for infant less than 1 month exposed to pertussis positive individual?
Azithromycin
erythromycin has increased risk of leading to pyloric stenosis
What is a possible complication of pertussis in young infant?
pyloric stenosis
What is the treatment for cat scratch disease?
Azithromycin
What is the most common presentation of group B strep infection in infant up to 6 days of life?
sepsis
What is the likely diagnosis of a newborn with IUGR, hydrocephalus, microphthalmia, chorioretinitis, and generalized cerebral calcifications on CT?
Toxoplasmosis
Toxoplasma gondii
What is the likely diagnosis of patient in moutainous state west of Mississippi river who presents with non-pruritic maculopapular and petechial rash of ankles and wrist that spreads centrally along with fever, malaise, myalagias?
Rocky Mountain Spotted Fever (RMSF)
vector: dermacentor andersoni
What is the treatment for Rocky Mountain Spotted Fever (RMSF)?
Doxycycline
What is the most likely diagnosis of patient with fever, abdominal pain, cramping and bloody diarrhea with spiral/ helical shaped gram negative bacilli after BBQ or camping in the summer?
Campylobacter jejuni (undercooked poultry, contaminated water)
What is a complication of campylobacter jejuni infection?
Guillian Barre syndrome
GBS
What is a common finding on CBC or peripheral smear for an EBV infection?
absolute lymphocytosis with more than 10% atypical lymphcytes
What is the likely etiology of 1-3 year old with protracted nasal congestion with thick yellow nasal discharge, low grade fever, tender anterior cervical lymphadenopathy with erythematous crusting lesions around nose/ mouth?
Streptococcosis (streptococcal fever)
due to S. pyogenes
What is the cause for meningitis with a gram negative diplococci finding on CSF?
Neisseria meningitides serotype B
what is the vaccination schedule for meningococcal prevention in infant with history of asplenia?
Menveo at 2, 4, 6, and 12 months
What is a complication of incision and drainage of non-TB lymphadenitis?
draining sinus tract
What is the most likely diagnosis and possible treatment for pt with painful, group, deep seated vesicles with clear fluid on erythematous base on volar portion of finger?
Herpetic Whitlow
tx: acyclovir
What is the best management for an asymptomatic infant born to a mother with untreated gonorrhea to prevent ophthalmia neonatorum?
IM ceftriaxone (max 125 mg)
What is the treatment for patient with severe ear pain, swollen and tender auricle, and severe auditory inflammation in the setting of swimming and immunocompetent state (type 1 DM)?
Ciprofloxacin
for Pseudomonas
What is the most likely diagnosis for patient with fever, painful lymphadenopathy, painful erythematous ulcer, malaise, anorexia and hepatosplenomegaly in setting of being around rabbits?
Tularemia
What is the most likely diagnosis for child with IUGR, sensorineural deafness, congenital cataracts, raised bluish papular eruptions rash?
Congenital Rubella
Blueberry muffin rash
What cardiac abnormality is associated with Rubella?
PDA (continuous murmur heard best at left infraclavicular area and radiates to left back)
What are 3 maternal conditions have absolute contraindications to breastfeeding?
- HIV
- HTLV-1
- HTLV-2
What is the most likely diagnosis for patient with headache, malaise, fever, erythematous enlarged tonsils, conjunctivitis, preauricular and cervical lymphadenopathy, and rhinitis?
Adenovirus
What is a common complication of Adenovirus?
Hemorrhagic cystitis
What is the most likely diagnosis for pt presenting with ear pain, ataxia, vertigo, tinnitus, and vesicles and crusted vesicles with erythema found in ear, tongue and soft palate?
Ramsay Hunt Syndrome
due to shingles eruption
What is complication of Ramsay Hunt Syndrome?
Facial nerve palsy
What is the most likely diagnosis for 4-12 week infant with staccato like cough, tachypnea, rales without wheezing, hyperinflation with minimal interstitial and alveolar infiltrates and eosinophilia?
Chlamydia trachomatis
tx: azithromycin or erythromycin
A patient presenting with tender, swollen rash described as sharply defined, slightly elevated border most likely has …. due to …..
Erysipelas; Group A Strep
What is the treatment for lyme arthritis?
Doxycycline 100 mg BID for 28 days
What are the 4 factors that increase the risk for antibiotic resistance in S. pneumoniae otitis media?
- daycare attendance
- recurrent infection
- recent antibiotic use
- less than 2 years old
What is the most likely diagnosis for patient presenting with jaw infection found to have beaded, branching chains of gram positive rods and sulfur granules?
Actinomyces infection
What is the most likely complication of parovirus infection in pregnancy?
non-immune fetal hydrops
what is the most likely diagnosis for infant with numerous reddish-purple nodules in the diaper area not sparing the skin folds and with no neoplastic changes on biospy?
Candida albicans
What is the timeframe in which a newborn is a risk from severe congenital varicella infection if mother has primary infection during pregnancy?
if occur 2-5 days before delivery
baby exposed to active varicella without passive IgG transfer protection
What is the diagnostic test of choice for osteomyelitis?
MRI
What is the CBC finding associated with pertussis (Bordetella pertussis)?
elevated WBC with lymphocytosis
… sign is exaggerated sand paper like rash in skinfolds of the inguinal and axillary region and associated with ….
Pastia; Scarlet fever
What is the most likely diagnosis for partially/ un-immunized child who presents with retroauricular, posterior cervical, and post occipital lymphadenopathy and reddish pink spots (Forchheimer spots) on the soft palate?
Rubella
German Measles
What anti- TB medications results in orange colored urine?
Rifampin
What is the most likely diagnosis for a patient with a penetrating eye injury and found to have ring abscess formation in the cornea?
Bacillus cereus infection
What medical condition can be worsened by an acute strep pharyngitis infection?
OCD or tic disorder
What is the most likely diagnosis of newborn with microcephaly, microophthalmia, shortened malformed lower extremities with numerous areas of scarring and bilateral cataracts?
Congenital Varicella
What abnormal chemistry finding is associated with Rocky Mountain Spotted Fever?
hyponatremia
What common viral infection of young children can be associated with bulging fontanel with normal CSF findings?
Roseola
What is the treatment for group C streptococcal pharyngitis?
penicillin
What is the time frame in reach sinusitis should be considered in patient with nasal congestion, sinus pain, and sore throat?
after 7-10 days
What is the most likely diagnosis for young child presenting with worsening hoarseness, coarse muffled cry that does not change with positioning, and has soft tissue mass on vocal cords in setting of maternal history of genital warts?
Recurrent respiratory papillomatosis (due to HPV type 6 or 11)
What is the most likely cause of gastroenteritis in patient who was recently at water park and has small rounded oocytes in stool?
Cryptosporidium
What is the treatment for cryptosporidium gastroenteritis lasting longer than 2 weeks or severe?
Nitazoxanide
Is the interpretation of tuberculin skin testing the same for individuals who have and have not received the BCG vaccine?
Yes
What is the treatment for chlamydial conjunctivitis?
Azithromycin or erythromycin
What is the possible complication of erythromycin use in an infant?
pyloric stenosis
What is the alternative prophylactic medication for chloroquine resistant malaria?
Doxycycline
What is the treatment for pneumocystis jiroveci (PCP) pneumonia (bilateral interstitial infiltrates in infant with history of limited prenatal care)?
Bactrim (trimethoprim/ sulfamethoxazole) and steroids
What is the most likely diagnosis for patient presenting with altered mental status, intensely erythematous generalized rash, fever, mucous membrane injection, elevated transaminases, elevated creatinine kinase after prodrome of vomiting/ diarrheal illness?
Toxic Shock Syndrome
What is the most common sequelae after bacterial meningitis (especially from pneumococcal meningitis)?
hearing loss
How many cases at a child care setting warrant prophylaxis for meningococcal meningitis?
1
What is the most likely diagnosis for patient presenting with chronic draining lesions after water exposure (fish tank, swimming pool) that is resistant to most routine antibiotics?
Mycobacterium marinum
What is the most likely diagnosis for immigrant from Eastern Europe who presents with malaise, headache, sore throat, cough, coryza, posterior cervical/ postauricular/ suboccipital lymphadenopathy and sot palate petechia distributed among larger reddish spots?
Rubella virus
German Measles
…. sign is characterized by soft palate petechiae and/or larger reddish spots
Forchheimer (associated with Rubella/ german measles)
What is the most likely diagnosis for child presenting with microcephaly, hearing loss, developmental delays, congenital cataract and PDA with pulmonary stenosis (ejection murmur heard at 2nd intercostal space with ejection click)?
Congenital Rubella
… is characterized by numerous small, irregular, erythematous spots with a minute, bluish-white center located on the buccal mucosa and associated with ….
Koplik spots; Measles (Rubeola)
… is characterized by larger lymphocytes with large eccentrically placed indented and folded nuclei and associated with ….
Atypical Lymphocytes; EBV
What is the likely diagnosis for patient presenting with sore throat who develops rash days later after starting Amoxicillin for suspected strep throat?
EBV (Mononucleosis)
What is the best way to distinguish positive PPD due to mycobacterium tuberculosis infection versus positive PPD due to prior BCG vaccine?
Interferon gamma release assay (IGRA- quantiferon gold test)
What is the characteristic rash associated with Rubella infection?
fine, discrete, irregular, coalescing, pinkish red macules located on face and trunk
What is the best treatment for an Enterococcus UTI?
Ampicillin
What bacteria is associated with causing meningitis in patients with cochlear implants?
Streptococcus pneumoniae
What is the most likely diagnosis for child presenting with several days of sore throat, malaise, arthralgia and fever with sudden onset pruritic erythematous symmetrical swelling of hands and feet, and painful pruritic papules, petechiae and purpura of hands and feet?
Papular Purpuric Gloves and Socks syndrome
due to Parvovirus B19
What pathogen is associated with epidemic keratoconjunctivitis (red eye with crusting) in the swimming pool setting?
Adenovirus
What is consider a positive tuberculin skin test in children less than 4 years old?
induration greater than 10 mm
What is the most common cause of brain abscess formation in infant?
Citrobacter koseri
What is the treatment for tularemia?
gentamicin or streptomycin
What is the most likely diagnosis for patient presenting with tender regional lymphadenopathy and tender erythematous papules following kitten/ cat scratch?
Bartonella Henselae infection
Cat scratch disease
What infection that results in light colored crusty lesions on back and chest that become lighter when exposed to sunlight has a “spaghetti and meatball” appearance on skin scraping?
Malassezia furfur
tinea versicolor or pityriasis
When can a child return to daycare/ school if they are diagnosed with Parvovirus B19 infection?
once the rash appears (no longer infectious)
What is the recommendation for measles postexposure prophylaxis for infants less than 6 months?
Measles IgG IM or IVIG within 6 days of exposure
What is the recommendation for measles postexposure prophylaxis for children 6 months and older?
MMR vaccine within 72 hours of exposure or measles IgG or IVIG within 6 days of exposure
What is the recommendation for measles postexpsoure prophylaxis for HIV positive children who are immunosuppressed?
IVIG within 6 days of exposure
despite vaccine history and serologic results
What disorder can occur in a child with recent Varicella or Influenza infection (or live attenuated vaccine) if given salicylate?
Reye syndrome
no aspirin after varicella vaccine for 6 weeks
What is the most likely diagnosis for patient presenting with strep throat, fever, and maculopapular rash starting on extensor surfaces of distal extremities and spreading centripetally with gram positive rod only growing on blood rich media?
Arcanobacterium haemolyticum
What is the treatment for Parinaud oculoglandular syndrome?
Azithromycin
