This is the first part of a two part case.
A 22 year old college student presents to the emergency department with a temperature of 39 C, photophobia, and confusion. This began about 12 hours ago. She tried acetaminophen with minimal relief. She complains of a severe, generalized headache. Although she has had migraines in the past, this is much worse. She takes an oral contraceptive, smokes and drinks occasionally, and uses marijuana (last use last night). When you flex her neck, you note that her hips spontaneously flex. When her hips are flexed 90 degrees, she cannot fully extend her knees. Here's a diagram of those maneuvers:
She has no papilledema and no focal neurologic deficits.
Challenge: What's your next diagnostic test? Will you give empiric treatment?
1. What's the leading diagnosis?
2. What is shown in the diagrams above?
Both images are in the public domain.