Toxicology 2011 ronde 1
Anamnese:
A
34-year-old emergency medical technician with a history of hypertension was
admitted to the hospital for a wide complex tachycardia. She had a history of
palpitations for which she had received an extensive cardiology workup and a
sotolol prescription. Other medications included esomeprazole, sertraline and
triamterene/hydrochlorotiazide. She was already scheduled for an implanted loop
recorder to definitively exclude organic disease.
She reacts agitated, tremulous and had nausea with episodes of emesis. She
developed runs of stable ventricular tachycardia. She refused to answer
questions, which might suggest Munchhausen syndrome. Labs: serum bicarbonate 15
mmol/L, anion gap of 25.
Potassium 1.9 mmol/L.
We
consider salicylate and theophylline intoxication, but we can’t fit sertraline
in the picture.
Can you help us to clear this
case
Composition: serum: caffeine 127 mg/l, salicylic acid 91.6 mg/l, sotalol 2.92 mg/l, sertraline 0.457 mg/l
This case is
based on Clin. Toxicology 2009;47: (9) abstract 294 : Williams cs Vanderbilt UMC,
Nashville USA: Munchausen Syndrome from High Dose Caffeine Presenting with
Ventricular Dysrhythmias.
In this report the laboratory found a therapeutic level of metoprolol, although
albuterol (=salbuterol) was prescribed. I changed this to sotalol (therapeutic,
3 mg/L), because sotolol is not so easy to detect with the STIP-system (analytical
disturbance by caffeine. However, the signal of sotalol is mostly only about 2%
of caffeine and therefore sotolol is often overlooked and the influence on the
caffeine level is insignificant).
Because of to the story and cross reactivity on the immunoassay, I expected that
many of you would report theophylline. 42 contestants found caffeine with STIP
or RP-HPLC, 14 of you did not. Theophylline was seen quite often, however in
clinical insignificant levels, probably as a result of contamination, while
7-demethylation of caffeine makes theophylline! Sertraline is therapeutic, maybe
slightly elevated. Salicylic acid (90 mg/L) won’t cause any trouble in a 34-year
old, unless this is due to chronic dosing. Unfortunately only few labs did find
sotalol. Besides both sertraline and salicylic acid showed quantitative poor
results, not acceptable in TDM. It is always questionable if these results are
sufficient in clinical toxicology. The abstract tells us that during a extensive
urine screening also cyclobenzaprine (not used in the Netherlands) and
diphenhydramine were found. “Documentation by the primary care provider at
follow-up noted that the patient stated she had taken “diet pills””. The
next day the patient recovered spontaneously from the, by caffeine overdosing
induced ventricular tachycardia.
