Trimeresurus stejnegeri Envenoming during Pregnancy
Yen-Chia Chen, Min-Hui Chen, Chen-Chang Yang, Yen-Wen Chen, Lee-Min Wang, and Chun-I Huang*
Department of Emergency Medicine, Department of Medicine, and Division of Clinical Toxicology, Department of Respiratory
Therapy, Taipei Veterans General Hospital, Taipei, Taiwan, Republic of China; Institute of Emergency and Critical Care Medicine,
National Yang-Ming University, Taipei, Taiwan, Republic of China; Center for Drug Evaluation, Taipei, Taiwan, Republic of China;
Department of Environmental and Occupational Medicine, School of Medicine, National Yang-Ming University,
Taiwan, Republic of China
Abstract. Snake envenoming in pregnancy may cause fetal death and maternal mortality or morbidity. However,
little is known about the toxic effects and optimal management of snake envenoming because of the rarity of cases. We
report three cases in Taiwan in the past 15 years of pregnant women who were treated successfully after being bitten by
Trimeresurus stejnegeri with local envenoming. Two of the three patients received treatment with equine-derived
hemotoxic bivalent F(ab')
2
antivenom without development of any adverse effects. All three women recovered un-
eventfully and subsequently had normal deliveries. Telephone follow-up of the three children 6–10 years later showed
no developmental delay of the children.
INTRODUCTION
Snake bite is a common medical emergency worldwide.
Much information is available regarding the effect of snake
venom on non-pregnant women and treatment protocols.
However, little is known about snake bite during pregnancy.
To provide more information on snake envenoming during
pregnancy, we report three pregnant women who were bitten
by a green habu (Trimeresurus stejnegeri). The types of snake
bites were documented on medical charts and originally clas-
sified in emergency departments by identifying the snake
brought by the patient or by snakes in pictures identified by
the patients.
CASE REPORT
Case 1. A 32-year-old pregnant woman who was at 17
weeks of gestation was bitten by a green habu on the dorsal
region of her left foot on July 10, 1995. She initially had severe
local pain, followed by swelling and bruising of the foot. She
visited a local hospital 2.5 hours after the venomous snake
bite and had progressive swelling of the left leg and ecchy-
mosis around the fang marks. She received treatment with
toxoid and empirical antibiotics. She was referred to our toxi-
cologic service nine hours after the snake bite.
On arrival at the toxicologic service, the patient’s vital signs
were normal; however, the swelling had progressed to her left
thigh. Routine laboratory examinations showed leukocytosis
with a white blood cell count of 13,400/mm
3
and a positive
result on a urine pregnancy test. One vial of equine-derived
hemotoxic bivalent F(ab')
2
antivenom was given 12.5 hours
after the snake bite, and she was admitted to the clinical
toxicology ward. She did not develop any adverse reactions to
the antivenom, and the local swelling disappeared promptly
after the administration of antivenom. On day two, her
thrombin time and activated partial thromboplastin time were
normal. Monitoring of the fetus did not find any evidence of
hypoxia, and there was no vaginal bleeding. The patient was
discharged uneventfully on the fourth day after admission and
delivered a normal baby at 40 weeks of gestation (23 weeks
after the snake bite). Telephone follow-up 10 years later
showed no developmental delay of the child.
Case 2. A 36-year-old pregnant woman who was at 8 weeks
of gestation was bitten by a green habu over proximal part of
her right middle finger on December 12, 1996. Thirty minutes
later, she was sent to a community hospital with local pain,
bleeding, and swelling around the fang marks. Antivenom
was not administered at the community hospital because of
the fear of possible adverse effects. She had persistent pain
and progressive swelling of right hand and was transferred to
our toxicologic service approximately four hours after the
snake bite.
On arrival, her vitals signs were normal. Physical examina-
tion showed that bleeding had stopped at the bite site, but
ecchymosis and swelling of right forearm were noted. Labo-
ratory data, including liver enzyme levels, renal function, pro-
thrombin time, activated partial thromboplastin time, and
complete blood counts were unremarkable except for mild
leukocytosis with a white blood cell count of 11,600/mm
3
and
a positive result on a urine pregnancy test. Because mild local
envenoming was suspected without evidence of further pro-
gression, a clinical toxicologist recommended only supportive
care. Her condition continued to improve, and she was dis-
charged on the third day after admission. During hospitaliza-
tion, monitoring of the fetus’s condition did not show any
abnormality. The patient gave birth to a normal baby girl at
39 weeks of gestation (31 weeks after the snake bite). Tele-
phone follow-up of the child eight years later showed no
growth retardation or intellectual disabilities.
Case 3. A 22-year-old pregnant woman who was at 28
weeks of gestation was bitten by green habu over right wrist
on April 20, 1999. She came to a local hospital with swelling
of right wrist and hand one hour after the snake bite and
received one vial of equine-derived hemotoxic bivalent
F(ab')
2
antivenom. However, the symptoms rapidly wors-
ened, and she was transferred to our emergency department
two hours after the snake bite.
On arrival at the emergency department, physical exami-
nation showed local erythema, bleeding from fang marks, and
progressive swelling of right forearm. Laboratory examina-
tions were remarkable for mild leukocytosis with a white
blood cell count of 13,900/mm
3
and mild anemia with a he-
moglobin level of 11.3 g/dL. Two vials of hemotoxic bivalent
* Address correspondence to Chun-I Huang, Department of Emer-
gency Medicine, Taipei Veterans General Hospital, 201, Shih-Pai
Road Section 2, Taipei 112, Taiwan, Republic of China. E-mail:
cihuang@vghtpe.gov.tw
Am. J. Trop. Med. Hyg., 77(5), 2007, pp. 847–849
Copyright © 2007 by The American Society of Tropical Medicine and Hygiene
847