WBR0063

Author	PageAuthor::William J Gibson (Reviewed by Yazan Daaboul)
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Microbiology
Sub Category	SubCategory::Neurology, SubCategory::Infectious Disease
Prompt	[[Prompt::A 28-year-old man began experiencing numbness in his toes which progressed to symmetrical distal muscle weakness of his lower limbs and currently includes the entire lower limbs and the distal upper limbs. A lumbar puncture is performed and CSF findings demonstrate increased protein with a normal cell count. The patient is started on intravenous immunoglobulin (IVIg). Which of the following describes the organism most likely to have infected this patient prior to his developing this condition?]]
Answer A	AnswerA::Oxidase-positive, gram-negative, glucose-nonfermenting, and motile rod
Answer A Explanation	AnswerAExp::Campylobacter jejuni is a comma shaped, oxidase-positive, gram-negative, glucose-nonfermenting, and motile comma-shaped organism that grows at 42 °C. It is classically associated with GBS.
Answer B	AnswerB::Oxidase-positive, gram-negative, glucose-fermenting, and motile rod
Answer B Explanation	AnswerBExp::''Campylobacter jejuni'' is glucose-nonfermenting rod.
Answer C	AnswerC::Oxidase-negative, gram-negative, glucose-fermenting, and non-motile rod
Answer C Explanation	AnswerCExp::''Campylobacter jejuni'' is a glucose-nonfermenting and motile rod.
Answer D	AnswerD::Oxidase-positive, gram-negative, glucose-nonfermenting, and non-motile rod
Answer D Explanation	AnswerDExp::''Campylobacter jejuni'' is a motile rod.
Answer E	AnswerE::Oxidase-negative, gram-positive, glucose-fermenting, and motile rod
Answer E Explanation	AnswerEExp::''Campylobacter jejuni'' is an oxidase-negative, glucose-nonfermenting rod.
Right Answer	RightAnswer::A
Explanation	[[Explanation::The patient most likely has Guillain-Barré syndrome (GBS), an acute progressive autoimmune demyelinating disease of peripheral nerves. Guillain-Barré is typically associated with a preceding history of Campylobacter jejuni upper respiratory tract or gastrointestinal infection. Campylobacter jejuni is an oxidase-positive, gram-negative, glucose-nonfermenting, and motile rod that grows at 42 °C. Educational Objective: Guillain-Barré is known to be preceded by Campylobacter Jejuni, an oxidase-negative, gram-negative, glucose-fermenting, and motile comma-shaped, rod that grows at 42 °C. References: First Aid 2014 page 140 (Camplyobacter) First Aid 2014 page 484 (Guillan-Barré)]]
Approved	Approved::Yes
Keyword	WBRKeyword::Microbiology, WBRKeyword::Neurology, WBRKeyword::Bacteria, WBRKeyword::Gram stain, WBRKeyword::Autoimmune, WBRKeyword::Autoimmunity, WBRKeyword::Guillan-Barré, WBRKeyword::GBS, WBRKeyword::Campylobacter, WBRKeyword::Campylobacter jejuni
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::