Welcome to the 161st FOAMed Quiz.

Question 1
A seventeen year old male presents to the emergency department with severe pain in his scrotum for several hours. During physical examination you see a swollen and red scrotum. Elevation of the scrotum increased the pain and did not give a relief of symptoms. We call this a negative Prehn’s sign.
Which of the following diagnoses is most likely in patients with negative Prehn’s sign?
A: Acute epididymitis
B: Testicular Torsion
The corrects answer is B.
Life in The Fast Lane covered the eponym Prehn’s sign this week in their blog.
Prehn’s sign (1934) is named after the American urologist Dougles Theodore Prehn. It is most commonly described as elevation of the scrotum not decreasing the pain in the scrotum. This clinical sign may help to differentiate between testicular torsion and acute epididymitis. It should always be followed by imaging to confirm the diagnosis.
Douglas Prehn

Question 2
Management of children with torus fractures still often includes application of a cast. The evidence behind treatment without immobilization is of low quality. At least so far.
In the recently published FORCE trial, 965 children (aged 4–15 years) with a distal radius torus fracture were randomly allocated to the ”offer of bandage” group or rigid immobilization group. 94% of the participants in the “offer of a bandage” group choose for bandage instead of rigid immobilization.
The primary outcome was pain on day three. Secondary outcomes included pain or function during the 6 weeks of follow-up.
What did the authors find?
A: Pain at day three was equal in both groups and there was no difference in pain and function during 6 weeks follow-up
B: Pain at day three was higher in the bandage group, but there was no difference in pain and function during 6 weeks follow-up
C: Pain at day three was equal in both groups, but patients in the bandage group reported reduced function during 6 weeks follow-up compared to the immobilization group
D: Pain at day three was higher in the bandage group and patients in the bandage group reported reduced function during 6 weeks follow-up compared to the immobilization group
The correct answer is A.
Don’t forget the Bubbles covered the paper last week.
‘’This trial found equivalence in pain at 3 days in children with a torus fracture of the distal radius assigned to the offer of a bandage group or the rigid immobilization group, with no between-group differences in pain or function during the 6 weeks of follow-up.’’
The FORCE trial
Question 3

The dose of intravenous insulin in hyperkalemia is often adjusted for renal dysfunction. Patients with renal dysfunction typically receive 5 IU instead of 10 IU to avoid hypoglycemia.
In this recently published retrospective study, 377 patients with Chronic Kidney Disease (CKD) stages 3a, 3b, and 4 and hyperkalemia were analysed. 186 patients received 5 units and 191 patients received 10 units of insulin.
What did the authors find?
A: More patients receiving 10 units of i.v. insulin had hypoglycemic events, but there was no difference in decrease of serum potassium between the groups
B: There was no difference in hypoglycemic events and there was no difference in decrease of serum potassium between the groups
C: More patients receiving 10 units of i.v. insulin had hypoglycemic events and 10 units of i.v. insulin lowered serum potassium significantly more than 5 units of i.v. insulin
D: There was no difference in hypoglycemic events among patients receiving 5 vs. 10 units of i.v. insulin. However, 10 units of i.v. insulin lowered serum potassium significantly more than 5 units of i.v. insulin
The correct answer is D.
The paper was covered on UMEM last week.
Hypoglycemia occurred in 6.5% of patients who received 5 units of i.v. insulin and in 8.4% of patients who received 10 units of i.v. insulin (p = 0.476).
There was no difference in hypoglycemic events among patients with moderate renal dysfunction receiving 5 vs. 10 units of i.v. insulin for hyperkalemia. However, 10 units of i.v. insulin lowered serum potassium significantly more than 5 units of i.v. insulin.
Keep in mind this is a retrospective paper. In the 5 unit group, significantly more patients had CKD stage 4 (60% v 30%).
Question 4

Which of the following cardiac abnormalities are present in classic tetralogy of Fallot?
A: Atrial Septal Defect
B: Ventricular Septal Defect
C: Pulmonary Artery Stenosis
D: Coarctation of the Aorta
E: Ebstein Anomaly
F: Tricuspid Atresia
G: Overriding Aorta
H: Hypoplastic Left Heart
I: Right Ventricular Hypertrophy
The correct answers are B, C, G and I.
Geeky Medics covered tetralogy of Fallot last week.
It consists of:
Ventricular Septal Defect
Pulmonary Artery Stenosis
Overriding Aorta
Right Ventricular Hypertrophy
Tetralogy of Fallot
This quiz was written by Sophie Nieuwendijk, Denise van Vossen, Gijs de Zeeuw, Maartje van Iwaarden and Nicole van Groningen
Reviewed and edited by Rick Thissen





