Archive | November, 2014

mumps: out and about with epidemic parotitis

25 Nov

I recently saw a patient in the ED with fever, bilateral parotitis and trismus with inability to open mouth greater than 1 finger width, concerning for mumps. I thought this would be a great opportunity to review this disease and recent epidemiology data from the US



–viral illness

symptoms appear 14-18 days s/p infection. however, may be as short as 12 or as long as 25 days 

–those infected are contagious 2 days before sx onset and 5 days after sx onset



  • parotitis (95% of cases),
  • low-grade fever,
  • HA and stiff neck,
  • malaise,
  • loss of appetite,
  • hoarse voice,
  • orchitis (s/p puberty, may experience testicular atrophy, but rarely aspermia),
  • oophoritis (7% of post-pubertal females),
  • breast inflammation,
  • deafness u/l or b/l (1 in 20k cases).
  • infrequently causes aseptic meningitis.




–prevention: need 2 dose MMR. 80-90% effective


treatment: supportive care. NSAIDs, antipyretics, IVF, isolation. in patients with orchitis, also supportive care (bed rest, NSAIDs, testicle supports, ice packs)


–testing: IgG and IgM at UVa (PCR and viral cx available elsewhere)


Mumps exposure history IgM IgG Comments References
Unvaccinated; no history of mumps + + or − IgM may be detected for weeks to months; low levels of IgG may be present at symptom onset Meurman et al. 1982; Sakata et al. 1985
1–dose vaccine history + or − Likely + 50% of serum samples collected 1–10 days after symptom onset were IgM-positive; 50%–80% of serum samples collected >10 days after symptom onset were IgM-positive Narita et al. 1998; Jin et al. 2004; Krause et al. 2007
2–dose vaccine history + or − Likely + 13%–15% of serum samples collected 1–3 days after symptom onset were IgM-positive* Bitsko et al. 2008; Rota et al. 2009

*30%–35% of buccal samples collected 1–3 days after symptom onset were positive by real-time RT-PCR among persons with 2 doses of MMR (Bitsko et al. 2008; Rota et al. 2009)


epidemiology in the US

–reported US cases in 2014 from 1/1 to 8/15: 965 (438 reported in 2013)


US outbreaks in 2014: 

–central Ohio/ Columbus: 8/3-9/20. 484 cases. highest case report since 1979 outbreak (930)

–U of W-Madison: 25 confirmed cases as of 8/8/14

–U of I-Urbana-Champaign: 14 confirmed cases in 2014


Submitted by Paddy Fannon.



The Centers for Disease Control and Prevention. Website: Fast Facts About Mumps (24 March 2010). Retrieved 24 November 2014.


The Centers for Disease Control and Prevention. Website: 2014 Mumps Cases and Outbreaks (18 August 2014). Retrieved 24 November 2014.


The Centers for Disease Control and Prevention . Graph: Overview of Laboratory Confirmation by IgM Serology (13 April 2010). Retrieved 24 November 2014.


Wharton M, Cochi SL, Williams WW. Measles, mumps and rubella vaccines. Infect Dis North Am. 1990; 4(1):47



how useful is temple percussion for temporal arteritis?

21 Nov


prevalence of TA in the general population is less than 1%

American College of Rheumatology classification criteria (need 3/5):

  • temporal artery tenderness or decreased temporal artery pulse
  • new headache,
  • onset at > 50 years old
  • erythrocyte sedimentation rate > 50 in first hr
  • positive temporal artery biopsy.



analysis of 21 studies with temporal artery biopsies

  • 2 historical features that substantially increased the likelihood of TA among patients referred for biopsy
    • jaw claudication (positive LR, 4.2; 95% CI, 2.8-6.2)
    • diplopia (positive LR, 3.4; 95% CI, 1.3-8.6).
  • absence of any temporal artery abnormality was the only clinical factor that modestly reduced the likelihood of disease (negative LR, 0.53; 95% CI, 0.38-0.75).
  • Predictive physical findings included
    • temporal artery beading (positive LR, 4.6; 95% CI, 1.1-18.4),
    • prominence (positive LR, 4.3; 95% CI, 2.1-8.9),
    • tenderness (positive LR, 2.6; 95% CI, 1.9-3.7).


retrospective chart review of 98 incident cases of GCA (giant cell arteritis)

  • of the 25 (out of 98) with a clinically abnormal temporal artery (e.g. tenderness)
    • 22 (88%) were biopsy-positive
    • 3 (12%) were biopsy negative
  • of the 73 (out of 98) with a clinically normal temporal artery
    • 46 (63%) were biopsy-positive
    • 27 (37%) were biopsy negative



how useful is temporal artery percussion?  not that great, but it’s part of the puzzle (and the ACR criteria), so it may increase the likelihood of the diagnosis.  just don’t rely on it in isolation.


References: JAMA article; Thierry Zenone and Marie Puget Sensitivity of clinically abnormal temporal artery in giant cell arteritis International Journal of Rheumatic Diseases 16; picture 1, picture 2

wisdom from coaches

17 Nov

Came across this video again recently, and figured I’d share some of the inspiration.  

If you’re a sports fan, you may or may not know about coach Jim Valvano, a former NC State basketball coach, who died of cancer not long after giving the speech below.  He’s better known as “Jimmy V,” which may sound familiar to some.  


For just a glimpse into the patient side of things, or if you need an inspirational pep talk of your own, spend a few minutes and check it out.  


Some words of wisdom:

Take time every day to laugh, to think, to cry.


“Cancer can take away all my physical abilities.  It cannot touch my mind, it cannot touch my heart, and it cannot touch my soul.”


“Don’t give up. Don’t ever give up.”



References: youtube video; wikipedia for more info on Jimmy V

PECARN themes

13 Nov

Why don’t we just CT everybody?

  • estimated risk of lethal malignancy from a head CT
    • 1 year old -> 1 in 1000-1500
    • 10 year old -> 1 in 5000
  • clinically-important traumatic brain injuries in children was RARE
    • 0.9% had a clinically-important traumatic brain injury
    • 0.1% underwent surgery
    • study of over 42,000 children


Check out MDCalc’s handy tool for using the PECARN rule, but some common themes prevail:

  • GCS =14 (PECARN study included those with GCS 14-15, but GCS <14 would not be particularly reassuring)
  • signs of basilar skull fx (or palpable fx if < 2yo)
  • altered mental status (e.g. Agitation, somnolence, repetitive questioning, or slow response)
  • if <2 yo, scalp hematoma
  • LOC
  • vomiting
  • severe headache
  • severe mechanism of injury


risk of clinically important TBI, if you had:

  • none of the above: risk is <0.05 %
  • any of the RED clues: risk is 4+ %, probably should CT
  • no RED, but any of the other clues: risk 0.9%, consider obs vs CT


References: MDCalc; picture


procedure video: one-handed surgical knot

10 Nov

came across this useful refresher video on Youtube.  If you only have 60-seconds, start watching at the 2:00 mark for the first pass/tie.

Then skip to the 3:00 mark for the 2nd pass/tie.


If you want to watch it done with actual suture (with some trippy music in the background), check out this one.

There you go.


References: video with audio explanation; trippy music video.


how good is your precordial thump?

7 Nov


tough finding data on this (if you find more, please send it my way):

one study with 2 cardiologists:

  • cardiologist 1: 6.3–7.1 J
  • cardiologist 2: 8.8–10.4 J
  • ventricular arrhythmia terminated in only 2/155 patients


The Good:

deliver mechanical force to attempt defib (see mechanism below)

you can’t kill dead (little downside, aside from possible trauma, depending on strength)


The Bad:

if its not v-fib, and you induce it with an R-on-T

rarely successful (0/180 successful thumps with fist or 30-40mph lacrosse balls in one study)

The Mechanism (theory):

  • conversion of mechanical energy to electrical current (mechanoelectric coupling)
  • initiated by chest impact with a rapid, transient rise in left ventricular pressure.
  • Increased pressure results in myocardial stretch
  • stretch-activated ionic channels including the K+ATP channels are activated and open, resulting in an inward current and subsequent depolarization.

In commodio cordis, this depolarization induces a premature ventricular beat which, if precisely timed during the upstroke of the T wave in the P-QRS-T electrical cycle, can result in ventricular fibrillation—in essence, the R-on-T phenomenon.

In intentional precordial thump, this depolarization can indeed defibrillate the myocardium and thus interrupting the ventricular dysrhythmia.

References: cardiologist thumps; lacrosse ball thumps + picture;  mechanism

magnesium sulfate: great NNT, ? mechanisms

6 Nov

from October’s EP Monthly article:


IV magnesium sulfate: to prevent hospital admission in severe asthmatics

  • NNT = 3


Mechanisms for…

  • concurrent hypokalemia
    • magnesium repletion is required to prevent renal excretion of potassium by inhibiting ROMK channels in the distal tubules
  • eclampsia
    • unclear but may be due to systemic or cerebral vasodilation
  • tocolytic
    • calcium antagonism
  • dysrhythmias
    • magnesium is required for functioning of the Na/K ATPase enzyme, and hypomagnesemia can lead to prolonged QT and PR.
  • severe asthma exacerbations,
    • bronchodilation, though the mechanism by which it produces this is not well established


References: epmonthly article,; picture