Chapter 10-4: Infectious Disease (Tick Dz)

Question 1

Rocky mountain spotted fever is caused by

Answer 1

tick borne disease caused by ricketttsia rickettsii

gram negative intracellular bacteria

Question 2

RMSF occurs most often in

Answer 2

april -september
tick infested areas of the south atlantic states
***despite the name none of the top 10 states are near the rocky moutons
#1 RF is travel to an endemic area in season where ticks are most active

Question 3

Presentation of RMSF

Answer 3

• fever, headache, rash
• symp approx 7 days after bite
• rash begins on 2nd - 5th day and consists of blanching, erythematous macular lesions tha progress to form petechiae or purpura
• *characteristically appears on the wrists and ankles and spreads proximally to ivovle the funk and head over several hours
• some kids have impairment of mental status

Question 4

Initial abx therapy

Answer 4

should cover for meningitidis too

• doxycycline is effective in all age groups
• cefotaxime or ceftriaxone should be added in meningococcemia is a possiblity

Question 5

Lyme disease is caused by

Answer 5

infection w/ spirochete bacterium borrrelia burgdorferi that lives in deer ticks and western black legged ticks

Question 6

Lyme disease occurs most often in

Answer 6

• souther new england, southern new york, new jersey,easter pennsylvania, maryland, delaware, minnesota, and wisconsin
• highest in kids 5-9y/o
• mostly between april and october

Question 7

Risk factors for lyme dz

Answer 7

• increased occupational or recreational exposure

- tick must feed for 48 hours to transmit b. burgdoferi

Question 8

Clinical manifestation of lyme dz

Answer 8

-erythema migran (manifestation of early dz) appears at the site of thick bite 3 to 30 days after the bit
-begins as a red macule or papule and progressively enlarges to form a large, annular, erythematous lesion w/ central clearing (bullseye) up to 10 cm
-accompanied by fever, malaise, headache, arthraligas, myalgias
-early lyme dz may present w/ multiple erythema migran lesions, cranial nerve palsy, meningitis, carditis (heart block)
-late lyme dz (>6wks after bit) is arthritis usually involving the knee
(usually a clinical diagnosis baed on hx and exam)

Question 9

Treatment of lyme dz

Answer 9

• early localized = prevent early disseminated and late dz
• if young = amoxicillin or cefuroxime
• older than 8 = doxycycline