CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 9, October 2012
AFRICA
e9
Case Report
Prolonged coagulopathy related to coumarin rodenticide
in a young patient: superwarfarin poisoning
SERVET ALTAY, HUSEYIN ALTUG CAKMAK, GULSAH CEMILOGLU BOZ, SINAN KOCA, YALCIN VELIBEY
Abstract
Superwarfarins (brodifacoum, difenacoum, bromodialone
and chlorphacinone) are anticoagulant rodenticides that
were developed in 1970s to overcome resistance to warfarin
in rats.A 26-year-old previously healthy man was admitted to
the emergency department with epigastric pain, severe upper
and lower gastrointestinal haemorrhage, gingival bleeding
and melena. The patient stated that he had been healthy
with no prior hospital admissions and no personal or family
history of bleeding diathesis. The patient, who later admitted
attempted suicide, stated that he had taken 400 g rodenticide
including brodifacoum orally for five days prior to admis-
sion to hospital. He had oral mucosal bleeding, numerous
bruises over the arms, legs and abdomen, and an abdominal
tenderness, together with melena. Laboratory tests revealed a
haemoglobin level of 12.3 g/dl, leucocyte count of 9.1
×
10
9
/
l,
haematocrit of 28% and platelet count of 280
×
10
9
/
l. The
prothrombin time (PT) was
>
200
s (normal range 10.5–15.2 s)
and the activated partial thromboplastin time (aPTT) was
91
s (normal range 20–45 s). The INR (International normal-
ised ratio) was reported to be
>
17 (
normal range 0.8–1.2).
The thrombin time and plasma fibrinogen levels were in the
normal range. The results showed the presence of brodifa-
coum at a concentration of 61 ng/ml, detected by reversed-
phase liquid chromatography.
Keywords:
superwarfarin,brodifacoum,vitamin K, rodenticides,
coagulopathy
Submitted 9/5/11, accepted 8/6/12
Cardiovasc J Afr
2012;
23
:
e9–e11
DOI: 10.5830/CVJA-2012-051
Superwarfarins (brodifacoum, difenacoum, bromodialone
and chlorphacinone) are anticoagulant rodenticides that were
developed in 1970s to overcome resistance to warfarin in rats.
1
They are long-acting, fat-soluble anticoagulants with half-lives
between 16 and 220 days. They are 100 times more potent than
warfarin due to phenyl groups replacing the terminal methyl
group in the molecular structure.
1,2-4
Superwarfarins and warfarins are metabolised in the liver after
ingestion. Warfarin and superwarfarin interfere with vitamin K
metabolism by inhibiting both vitamin K epoxide reductase and
vitamin K reductase enzymes, causing accumulation of vitamin
K epoxide (the inactive form of vitamin K), thus preventing
γ
-
carboxylation of the vitamin K-dependent clotting factors II,
VII, IX and X.
3,5
The most commonly used superwarfarin is brodifacoum
(4-
hydroxy coumarin with a 4-bromo side chain, sold as D-Con:
Reckitt & Colman, Montvale, NJ).
6
Since superwarfarins are
widely used in stores and homes in both rural and urban
areas, there can easily be overexposure and intoxication,
leading to abnormal coagulopathy or bleeding and resulting in
severe clinical outcomes. Over 16 000 cases of superwarfarin
intoxication have been reported annually by the Poison Control
Centre’s toxic exposure surveillance system in the United States.
7
Epidemiological data show an increasing incidence of human
exposure to superwarfarins worldwide. The majority of cases
are related to accidental ingestion, mostly by children under
six years old. However, attempted suicide, psychiatric diseases,
deliberate self poisoning with denial (Munchausen syndrome)
and homicide are among other reported causes.
8,9
Here we report
on a young man with severe upper and lower gastrointestinal
haemorrhage caused by superwarfarin poisoning after ingestion
for attempted suicide.
Case report
A 26-year-old previously healthy man was admitted to the
emergency department with epigastric pain, gingival bleeding
and melena. The patient stated that he had been healthy with
no prior hospital admissions and no personal or family history
of bleeding diathesis. He also denied any renal, hepatic or
gastrointestinal diseases. There was no history of excessive
alcohol ingestion or smoking habit and his dietary recall showed
an adequate intake of vitamin K. The patient, who later admitted
attempted suicide, stated that he had taken 400 g rodenticide,
including brodifacoum orally for five days prior to admission
to hospital.
The physical examination revealed a blood pressure of
Department of Cardiology, Siyami Ersek Thoracic and
Cardiovascular Surgery Center Training and Research
Hospital, Istanbul, Turkey
SERVET ALTAY, MD
YALCIN VELIBEY, MD
Department of Cardiology, Cerrahpasa Medical Faculty,
Istanbul University, Istanbul, Turkey
HUSEYIN ALTUG CAKMAK, MD,
Department of Internal Medicine, Goztepe Training and
Research Hospital, Istanbul, Turkey
GULSAH CEMILOGLU BOZ, MD
SINAN KOCA, MD
