ID Flashcards
A healthy 7 yo boy is admitted with progressive cellulitis of his arm after scraping his wrist several days ago. Despite good dose bactrim x2 days, redness has continued to spread. He has a temp of 38.5 C, healing abrasion on right arm with 6cm surrounding erythema, no drainage or fluctuate, very tender. No allergies. Which is the most appropriate antibiotic?
A) ceftriaxone
B) linezolid
C) nafcillin
D) vanc
C. Nafcillin
Most non suppurative cellulitis are due to GAS or MSSA. GAS thought to be resistant to bactrim. A and B do treat these but are unnecessarily broad spectrum.
A 37day old with fever, poor feeding with a red, swollen area under infants right mandible that has rapidly worsened over the last 4 hours. The infant is ill appearing and irritable. Full sepsis eval done. CSF with WBC 400 and glucose of <5. Of the following, the CSF gram stain will most likely show:
A) gram negative coccobacilli
B) gram negative rods
C) gram positive diplococci
D) gram positive rods
C. This is cellulitis/Adenitis syndrome caused by late onset GBS.
Early onset GBS is spread:
A) due to exposure to vaginal
Flora
B) due to exposure to visitors
C) due to skin to skin transmission
D) due to transplacental transmission
A. Colonizes lower GI tract and vaginal canal in 15-35% of women. After membrane rupture, can ascend to the uterus or by mucosal surface contact during passage through the birth canal. Transplacental transmission is not known to occur.
Risk factors for early onset GBS include:
PROM (>18hrs)
Intrapartum fever
Intra-amniotic fluid infection
GBS bacteruria during pregnancy
Prior infant with GBS
A previously healthy 15yo M is seen for new onset seizures. His VSS, he is sleepy but avoidable and answering questions. Exam is unremarkable. A noncontrast CY shows several calcified lesions in the brain parenchyma. The most likely exposure is:
A) cat litter
B) sand boxes with dog feces
C) soil contaminated with human feces
D) undercooked pork
C. Neurocystercercosis is not caused by eating undercooked pork but by soil, food, water, or fingers contaminated with human feces that contain T solium eggs. Taeniasis (tapeworm intestinal infection) can be caused by ingested undercooked pork by consuming the tapeworm (has already completed its life cycle).
12 mo healthy F is admitted with AGE. On further history, family has been at the community pool daily this summer which was just closed for decontamination. What is the most likely cause of her symptoms?
A) rotavirus
B) cryptosporidium
C) entamoeba histolytica
D) salmonella
B. Crypto is commonly found in municipal water contaminated with human or animal feces. Pools can be a frequent site of contamination—affects infants and those drinking untreated drinking water
4yo boy admitted with AGE. Stools have been foul smelling and float on top of the water in the toilet. Family was just camping and child was found drinking from the stream. Most likely etiology?
A) salmonella
B) entamoeba histolytica
C) schistosomiasis
D) giardia
D. Giardia associated with steatorrhea (floats) and foul smell. From contaminated water, especially streams and lakes
A 6yo healthy girls has a right sided neck mass. She is febrile to 38.7 but otherwise well appearing. The mass is non-tender, non-fluctuant, movable, and the skin overlying is a violaceous hue. What treatment should you start?
A) short course oral macrolide
B) fine needle aspiration and radiation therapy
C) prolonged IV course of beta lactam antibiotic.
D) complete excision
D. This is non-TB mycobacterial lymphadenitis. Complete excision is best. Prolonged (12weeks) is an option, but doesn’t have to be IV (usually includes a macrolide). Close monitoring is also an option.
Match the following
A) blastomyces
B) Coccidiodes
C) histoplasmosis
D) sporothrix shenkeii
- Found in the Ohio and Mississippi River valley
- Infection from contamination from an open wound in skin
- Found in hot, dry soil in the desert
- Infection from inhalation of bird or bat droppings.
- Treated with itraconazole
- Treated with fluconazole
A) blasto: 1, 5
B) coccidio: 3, 6
C) histo: 1, 4, 5
D) sporothrix: 2, 5 (rose gardeners disease)
