Welcome to the 181th FOAMed Quiz.
Question 1
What is the most common risk factor for malignant otitis externa?
A: Immunosuppression
B: Age
C: Diabetes mellitus
D: Smoking
E: HIV
The correct answer is C.
EmDOCs Podcast covered this week malignant otitis externa (MOE).
MOE is a severe and progressive infection of the external auditory canal. The most common risk factor is DM, with an estimated 90% of patients with MOE having DM. It is thought to predispose due to microangiopathy, impaired wound healing and increased pH in diabetic cerumen.
Immunosuppression, including HIV, is another risk factor.
The disease is rare in children and mostly seen at age >65 years.
Question 2
In glaucoma, several different types of eye drops are used for lowering intraocular pressure (IOP). Link the correct medicine and mechanism of action:
A: Timolol
B: Latanoprost
C: Pilocarpine
D: Acetazolamide
1: Reduces production of aqueous humor via decreasing cAMP concentration in the ciliary body
2: Reduces production of aqueous humor via decreasing bicarbonate concentration
3: Causes the iris to contract
4: Increases drainage of aqueous humor
The correct answer is A-1, B-4, C-3, D-2.
This week’s REBEL Core Cast was about acute vision loss (including acute glaucoma and giant cell arteritis).
Acute glaucoma causes vision loss by damaging the optic nerve via high IOP. Open angle glaucoma is the most common form of glaucoma and is usually unnoticed until late in disease vision loss occurs. Closed angle glaucoma gives a painful vision loss, halos, nausea and vomiting. First-line therapy is beta-blockade (timolol).
REBEL Core Cast 96.0 – Acute Vision Loss I
Question 3
The effect of specialist consultation in the ED remains subject of debate.
In this recently published Canadian paper 829 patients in 11 ED sites with recent-onset uncomplicated atrial fibrillation or flutter were analyzed. Uncomplicated atrial fibrillation was defined as asymptomatic after rate or rhythm control. 364 (44%) of patients had specialist consultation.
What effect did specialist consultation in the ED have?
A: The ED length of stay was longer but patients had less ED revisits within 30 days
B: The ED length of stay was longer and patients had equal ED revisits within 30 days
C: The ED length of stay was shorter and patients had less ED revisits within 30 days
D: The ED length of stay was shorter but patients had more ED revisits within 30 days
The correct answer is B.
The paper was covered on CanadiEM last week.
After propensity-matching, specialist-consulted patients had a 0.6% lower risk of 30-day revisits than non-consulted patients. Median length of stay was 591 minutes for consulted patients and 300 minutes for patients without consultation. This means ED length of stay was almost double in specialist-consulted patients.
CJEM Visual Abstract: Effect of specialist consultation on emergency department revisits with uncomplicated recent-onset atrial fibrillation or flutter
Question 4
Oral anticoagulation, particularly warfarin, is associated with an increased risk of intracranial hemorrhage after head trauma. However, available data on delayed bleeds in anticoagulated patients are limited.
In this recently published observational study 69.321 patients with an emergency visit because of minor head injury (so without intracranial hemorrhage) were included. 58.233 (84.0%) patients were not on oral anticoagulation, 3081 (4.4%) had a warfarin prescription, and 8007 (11.6%) had a direct oral anticoagulant (DOAC) prescription.
The primary outcome was delayed intracranial hemorrhage, defined as a new intracranial hemorrhage within 90 days of the initial ED visit for a head injury where no intracranial hemorrhage was diagnosed.
What did the authors find?
A: Both patients on DOAC and patients on warfarin had a higher chance of delayed intracranial hemorrhage compared to patients that were not on anticoagulation
B: Only patients on DOAC had a higher chance of delayed intracranial hemorrhage compared to patients that were not on anticoagulation
C: Only patients on warfarin had a higher chance of delayed intracranial hemorrhage compared to patients that were not on anticoagulation
D: Neither patients on DOAC nor patients on warfarin had a higher chance of delayed intracranial hemorrhage compared to patients that were not on anticoagulation
The correct answer is C.
The paper was covered in UMEM last week.
Overall, 718 (1.0%) patients had a delayed intracranial hemorrhage within 90 days of ED visit for head injury. Among patients that did not receive anticoagulation, 586 (1.0%) had delayed intracranial hemorrhage, 54 (1.8%) of the patients on warfarin had delayed intracranial hemorrhage, and 78 (1.0%) patients on a direct oral anticoagulant had delayed intracranial hemorrhage.
Question 5
Which of the following antibiotics should be administered in patients with (suspected) Toxic Shock Syndrome (TSS) in order to suppress toxin production.
A: A third generation cephalosporin
B: Gentamicin
C: Penicillin G (Benzylpenicillin)
D: Clindamycin
The correct answer is D.
Toxic Shock Syndrome was covered in DFTB last week.
TSS is caused by either toxin production by Staphylococcus aureus or Group A Streptococci (GAS).
Clindamycin is added based on the ability of this drug to suppress synthesis of bacterial toxins. Since it is merely bacteriostatic and not bactericidal it should never be used as monotherapy for TSS, but always as an adjunct to a bactericidal antibiotic.
Toxic shock syndrome
This quiz was written by Sophie Nieuwendijk, Denise van Vossen, Nicole van Groningen, Jeroen van Brakel, Noortje Geerts and Renée Deckers
Reviewed and edited by Rick Thissen
