WBR0777: Difference between revisions
Jump to navigation
Jump to search
Rim Halaby (talk | contribs) No edit summary |
Rim Halaby (talk | contribs) No edit summary |
||
Line 23: | Line 23: | ||
[[Image:WBR0777.jpg]] | [[Image:WBR0777.jpg]] | ||
|Explanation=Lyme disease is a systemic animal-borne illness caused by the spirochete Borrelia burgdorferi transmitted by the Ixodes tick. The disease typically affects the skin, nervous system, musculoskeletal system and heart. The disease is mostly seen in the northeastern United States. Classically it has 3 phases. The | |Explanation=Lyme disease is a systemic animal-borne illness caused by the spirochete Borrelia burgdorferi transmitted by the Ixodes tick. The disease typically affects the skin, nervous system, musculoskeletal system and heart. The disease is mostly seen in the northeastern United States. Classically it has 3 phases. The initial phase involves a typical rash known as erythema migrans that expands forming a bull's eye pattern with central clearing. The first stage occurs between 2-20 days after the initial tick bite and inoculation. The second stage is characterized by neurologic manifestations including meningitis, AV nodal block, and Bell's palsy usually occurring several weeks after the inital bite. The final phase, occurring several months to years after the inital exposure, is characterized by chronic monoarthritis and migratory polyarthritis with associated cutaneous manifestations. Treatment is usually with ceftriaxone or doxycyline. | ||
Revision as of 03:51, 30 October 2013
Author | [[PageAuthor::Rim Halaby, M.D. [1]]] |
---|---|
Exam Type | ExamType::USMLE Step 1 |
Main Category | MainCategory::Microbiology, MainCategory::Pathophysiology |
Sub Category | SubCategory::Infectious Disease |
Prompt | [[Prompt::A 23 year old man presents to the clinic for an unusual looking rash that he first noticed today. He reports that although the rash feels slightly warmer than the surrounding skin, it is neither itchy nor painful. He does not report any recent lesion or bite to the area, but reports that he was recently on vacation on the northeastern coast where he went hiking for a few days. Otherwise, the patient denies any fatigue, chills, fever, headaches, myalgia or joint pain. On physical exam you notice the lesion shown below. What would you expect the patient to develop six months later if left untreated for his current condition? |
Answer A | AnswerA::Bell’s palsy |
Answer A Explanation | AnswerAExp::Bell's palsy usually occurs several weeks after the initial tick bite. |
Answer B | AnswerB::Third degree heart block |
Answer B Explanation | AnswerBExp::AV nodal blocks also occurs several weeks after the initial tick bite. |
Answer C | AnswerC::Recurrence of the same rash |
Answer C Explanation | AnswerCExp::The same erythema migrans rash can occur within a few weeks after the initial tick bite. |
Answer D | AnswerD::Meningitis |
Answer D Explanation | AnswerDExp::Meningitis also occurs several weeks after the initial tick bite. |
Answer E | AnswerE::Arthritis with severe joint swelling |
Answer E Explanation | AnswerEExp::Chronic monoarthritis and migratory polyarthritis is a typical manifestation of late Lyme disease occurring several months to years after the initial tick bite. |
Right Answer | RightAnswer::E |
Explanation | [[Explanation::Lyme disease is a systemic animal-borne illness caused by the spirochete Borrelia burgdorferi transmitted by the Ixodes tick. The disease typically affects the skin, nervous system, musculoskeletal system and heart. The disease is mostly seen in the northeastern United States. Classically it has 3 phases. The initial phase involves a typical rash known as erythema migrans that expands forming a bull's eye pattern with central clearing. The first stage occurs between 2-20 days after the initial tick bite and inoculation. The second stage is characterized by neurologic manifestations including meningitis, AV nodal block, and Bell's palsy usually occurring several weeks after the inital bite. The final phase, occurring several months to years after the inital exposure, is characterized by chronic monoarthritis and migratory polyarthritis with associated cutaneous manifestations. Treatment is usually with ceftriaxone or doxycyline.
Biesiada G, Czepiel J, Leśniak MR, Garlicki A, Mach T. Lyme disease: review. Arch Med Sci. 2012;8(6):978-82. |
Approved | Approved::No |
Keyword | WBRKeyword::Lyme disease, WBRKeyword::Borrelia burgdorferi, WBRKeyword::Erythema migrans, WBRKeyword::Migratory polyarthritis |
Linked Question | Linked:: |
Order in Linked Questions | LinkedOrder:: |