Ultrasonographic Diagnosis of Gastroesophageal Intussusception in a 7 Week Old German Shepherd

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Israel Journal of Veterinary Medicine  Vol. 70 (3)  September 2015 41 Gastroesophageal Intussusception
Ultrasonographic Diagnosis of Gastroesophageal Intussusception
in a 7 Week Old German Shepherd
Emery, L., Biller, D., Nuth, E. and Haynes, A.
Veterinary Health Center, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, United States of America.
*
Corresponding Author: Dr. Lee Emery, Te College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996, United States of America.
Phone: +865-974-8387 (W) +813-766-8465 (C). Email: lemery2@utk.edu
ABSTRACT
Tis case report describes the ultrasonographic diagnosis of gastroesophageal intussusception in a male 7
week old German Shepherd Dog. Te patient had no history prior to being purchased from a breeder 24
hours before presentation. Te owners noted persistent intermittent vomiting since that time and a single
roundworm was identifed once in a vomitus. A gastroesophageal intussusception was diagnosed via thoracic
radiographs and trans-abdominal ultrasound. Te spleen was noted to be within the distal esophagus in
concert with the stomach. Reduction of the intussusception was performed via laparotomy with bilateral
gastropexy. Te patient recovered uneventfully from surgery and is alive 4 months after discharge. Tis case
highlights the potential advantages of ultrasound in the diagnosis of gastroesophageal intussusceptions.
A review of the current literature is presented with discussions of possible etiologies of this rare form of
intestinal intussusception.
Keywords: Gastroesophageal; Intussusception; Ultrasound; German Shepherd; Dog; Puppy
INTRODUCTION
Gastroesophageal intussusception (GEI) is a rare condi-
tion encountered in veterinary medicine. (1, 2). It was frst
described in two German Shepherd littermates (3) and has
since been sporadically reported in the literature. GEI is most
often reported in dogs, typically male German Shepherd
Dogs of less than three months of age (1). Other reported
breeds include Husky (2), Labrador Retriever (4), Foxhound
(5), Afghan Hound (6), Doberman (7), Dalmatian (8),
Collie (9), Pug (10), domestic cat (11-13), Leopard (14),
and Hedgehog (15). GEI is defned as a retrograde invagina-
tion of the stomach into the dilated distal esophagus without
displacement of the gastroesophageal junction and difers
from hiatal hernia, in that the herniated organs remain within
the lumen of the esophagus (2, 16). Other organs, such as
duodenum, pancreas, omentum, and spleen, have been found
within the esophagus as well (1, 2). Esophageal disease, such
as congenital megaesophagus, abnormal esophageal motil-
ity or an enlarged esophageal hiatus is often a concurrent
fnding. Early reports indicated a high mortality with GEI,
but recent literature suggests a much lower mortality with
appropriate diagnosis and treatment (2, 4).
Tis report describes the ultrasonographic diagnosis of
gastroesophageal intussusception, along with the clinical
presentation and successful surgical treatment in a young
German Shepherd Dog.
CASE REPORT
A 7 week old male German Shepherd Dog (GSD) was
presented to the Kansas State University Veterinary Health
Center Emergency Service (Manhattan, KS, USA) for
vomiting. Te dog had been purchased from a breeder ap-
proximately 24 hours prior to presentation. No historical in-
formation related to the dog prior to purchase was available.
Israel Journal of Veterinary Medicine  Vol. 70 (3)  September 2015 Emery, L. 42
Te dog had started vomiting on the morning of presentation
and had vomited approximately 10 times. Te vomitus was
described as dark red and liquid consistency with abdominal
retching observed during every episode. Te owners reported
that the dog always vomited after eating or drinking but the
vomiting did not always occur immediately after a meal. Te
most recent vomitus prior to presentation contained multiple
grossly visible white roundworms. Te owners also described
soft stools with normal appetite, thirst, and urination.
On presentation the dog was quiet and responsive but
lethargic with a normal hydration status. Temperature
(101.0°F) and heart rate (160 beats/min) were within normal
limits. Abnormal physical parameters included a thin body
condition and mild tachypnea (56 breaths/min). During
physical examination, the dog vomited a dark red to brown
liquid.Abdominal pain was not detected on palpation.
Initial point-of-care diagnostics included a parvovirus
antigen snap test (IDEXX SNAP Parvo Test, Westbrook
MA, USA), packed cell volume (PCV), total solids (TS),
and blood glucose (BG). Results of these tests were within
the normal range, 37%, 5.8, and 113 mg/dL, respectively.
A full chemistry panel and complete blood count (CBC)
were performed. Te total leukocyte count (21,000/µL,
reference interval (RI) 6,000-17,000/µL) was elevated
with an increased segmented neutrophil count (16,500 /
µL, (RI) 3,000-11,500/µL) and monocyte count (1,700 /
µL, (RI) 100-800/µL) consistent with a stress leukogram.
Te patient had a mild normocytic hypochromic anemia
(HCT 34%, (RI) 37-55%) consistent with young age and/or
parasitism. Trombocytosis was present (582,000/µL, (RI)
164,000-510,000/µL) with moderate clumping. Biochemical
abnormalities associated with stress or the young age of the
dog included mild hyperglycemia (128 mg/dL, (RI) 73-113),
hypoproteinemia (4.3 g/dL, (RI) 5.4-7.6), hypoalbuminemia
(2.7 g/dL, (RI) 3.4-4.2), decreased BUN (5 mg/dL, (RI)
9-33), decreased creatinine (0.3 mg/dL, (RI) 0.5-1.5), in-
creased alkaline phosphatase activity (ALP) (216 U/L, (RI)
1-142), and hyperphosphatemia (9.5 mg/dL (RI) 2.4-6.4).
Additional biochemical abnormalities included hyponatre-
mia (143 mmol/L, (RI) 147-154), hypochloridemia (106
mmol/L, ref 108-118 (RI)), and elevated creatinine kinase
activity (CK) (770 U/L, (RI) 128-328) deemed consistent
with acute onset of vomiting.
Abdominal radiographs (Figures 1A and 1B) revealed
decreased serosal detail consistent with young age. In the
caudal thorax, an enlarged soft tissue opacity was visualized
consistent with the distal esophagus. Toracic radiographs
(Figures 2A and 2B) were obtained and showed marked
esophageal distension with an intraluminal gas opacity crani-
ally and a large oval shaped soft tissue opacity caudally.Te
Figure 1: Right lateral (1A) and ventrodorsal (1B) radiographic views
of the abdomen. Tere is decreased serosal detail in the abdomen. Te
stomach is not visualized. Tere is a soft tissue opacity mass in the
caudodorsal thorax in the location of the caudal thoracic esophagus.
1A
1B
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Israel Journal of Veterinary Medicine  Vol. 70 (3)  September 2015 43 Gastroesophageal Intussusception
trachea and heart were both displaced ventrally. Diferentials
included gastroesophageal intussusception, hiatal hernia, and
megaesophagus.
Abdominal and caudal thoracic ultrasound examination
(Figures 3A and 3B) were then performed with the patient
in dorsal recumbency (Acuson Sequoia 512, Seimens Medical
Solutions USA, Inc., Mountain View, CA). For the abdomen,
the ultrasound probe was positioned in both longitudinal
and transverse orientation and full sweeps were performed
of all abdominal organs as well as the abdomen in general.
Te caudal thorax was imaged with the patient in the same
position and the transducer positioned for evaluation of the
thorax through the liver and diaphragm. Both transverse
and longitudinal views were evaluated. A large mass efect
in the caudal thorax was identifed with a tubular segment of
gastrointestinal tract, consistent with stomach, and the spleen
both visualized within this mass. Te proximal small intestine
was seen coursing caudal to the stomach and across the level
of the diaphragm within the cranial abdomen.
Gastroesophageal intussusception with the spleen in the
esophagus was diagnosed and the dog was anesthetized for
surgery. A catheter was placed in the left cephalic vein. Te
dog was premedicated with Famotidine 1mg/kg IV (West-
Ward Pharmaceuticals, Eatontown, NJ) and Hydromorphone
0.1mg/kg IV (West-Ward Pharmaceuticals, Eatontown,
NJ). Anesthesia was induced with Propofol 3.9mg/kg IV
Figure 2: Right lateral (2A) and ventrodorsal (2B) radiographic views
of the thorax. Te cranial aspect of the thorax is not included in the
ventrodorsal image. Te thoracic esophagus is uniformly markedly
distended with gas opacity from the thoracic inlet to the base of the
heart and soft tissue opacity caudal to the base of the heart. Te heart
and trachea are deviated ventrally and to the right.
Figure 3: Transverse ultrasonographic images of cranial abdomen.
Tere was a large mass efect in the caudal thorax that consisted of a
rounded relatively hyperechoic rim containing hyperechoic material
and a tubular segment of gastrointestinal tract consistent with the
stomach (3A). Te proximal small intestine was seen coursing caudal
to the stomach and across the level of the diaphragm into the cranial
abdomen (3B).
2A
3A
2B
3B
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Israel Journal of Veterinary Medicine  Vol. 70 (3)  September 2015 Emery, L. 44
(PropoFlo® Abbott Laboratories, North Chicago, IL) and
he was maintained on inhalational Isofurane gas (IsoFlo®
Abbott Laboratories, North Chicago, IL).
An exploratory laparotomy was performed and the entire
stomach was identifed to be within the distal esophagus and
displaced cranially into the thoracic cavity. In addition,the
spleen was located within the distal esophagus following
the gastro-splenic ligament.Te duodenum was identifed
at the level of the esophageal hiatus but appeared otherwise
grossly normal. Te remainder of the abdominal exploration
was normal. Te stomach was reduced with gentle traction
back into the abdomen and the spleen was easily reduced by
traction on the stomach. Te stomach and spleen appeared
grossly normal on visual inspection, without evidence of loss
of viability, as determined by gross appearance, digital feel of
the stomach and spleen, and palpable pulses of the splenic
artery. Te esophageal hiatus was evaluated and the opening
was subjectively deemed to be of an appropriate diameter.
Right and left gastropexies were performed as previously
described, using 3-0 PDS and 2-0 PDS respectively in simple
continuous patterns (2).
Te dog was hospitalized in the Intensive Care Unit
(ICU) for recovery and post-operative care. Analgesia was
administered via Fentanyl 3-5 µg/kg/hr Constant Rate
Infusion (CRI) (Hospira Inc., Lake Forest, IL) for the frst
32 hours post-operatively. After which, Buprenorphine
0.032 mg/kg transmucosally (Buprenex Injectable
®
Reckitt Benckiser Pharmaceuticals, Richmond, VA) was
administered until discharge. Gastroprotectants were
administered due to the red discoloration of the vomitus
and included Metoclopromide 1mg/kg/day CRI (Hospira
Inc., Lake Forest, IL) until discharge, Famotidine 0.5 mg/
kg IV BID (West-Ward Pharmaceuticals, Eatontown, NJ)
until discharge, and Sucralfate 250 mg PO QID (Teva
Pharmaceuticals, Sellersville, PA) until discharge. Antibiotics
were administered due to concern of gastric mucosal integrity
and concern for aspiration pneumonia,Ampicillin/Sulbactam
22 mg/kg IV TID (Pauromedics Pharmaceuticals, Dayton,
NJ) followed by Amoxicillin/Clavulanate 18.9mg/kg PO
BID (Clavamox® Pfzer Inc., New York, NY).
Attempts were made to collect a fecal sample but
no bowel movements occurred during hospitalization.
Fenbendazole 50 mg/kg PO every 24 hours (Panacur
C®Merck Animal Health, Summit, NJ) was administered for
3 days post-operatively.Vital parameters including heart rate,
respiratory rate, temperature, blood glucose, pulse oximetry,
and blood pressure were also monitored post-operatively.
Te patient’s appetite remained excellent throughout the
entire post-operative period without any signs of vomiting
or regurgitation.
Te dog was discharged 3 days post-operatively and is
reportedly free of clinical signs upon last communication
with the owners 4 months after discharge. Instructions were
given to the owners at the time of discharge with recom-
mendations to recheck radiographs 7-10 days later, however
no follow-up radiographic data is available.
DISCUSSION
Te etiology of GEI is not well understood. In humans,GEI
seems to occur secondary to increased abdominal pressure,
decreased thoracic pressure, or sudden exercise in individu-
als with mechanical gastrointestinal (GI) disease such as
relaxation of the gastroesophageal sphincter, redundancy of
the gastric mucosa, or retrograde peristalsis (17, 18). People
describe intense pain that radiates from the abdomen up
through the neck, and it can often be confused with myo-
cardial infarction (19). Te vast majority of GEI reports are
in adults, with the frst case in a child published in 2004
(20). Typically only a small portion of the fundus invaginates
and it is rarely considered a surgical emergency (19). Tis
suggests that the pathogenesis in humans difers from that
in animals. Since most cases occur in very young dogs with
congenital megaesophagus, most theories suggest that it is
either a primary congenital problem, or, more likely, second-
ary to congenital esophageal disease (4, 17). Not all animals
with megaesophagus will develop GEI, making the true
pathogenesis unclear. Other conditions that may predispose
dogs for the development of GEI include gastrointestinal hy-
pomotility or hypermotility, inefective esophageal sphincter,
or increased abdominal pressure and decreased intrathoracic
pressure as in humans (2, 17).
In this puppy, as is the case in other reported instances
of this condition, the underlying etiology was not identifed.
Te physical examination fndings and bloodwork abnormali-
ties were non-specifc with regard to any underlying disease
process. Most of the abnormalities detected on CBC and
Chemistry analysis, such as mild anemia, thrombocytosis,
hypoproteinemia, hypoalbuminemia, decreased BUN and
creatinine, increased ALP, and hyperphosphatemia, were
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Israel Journal of Veterinary Medicine  Vol. 70 (3)  September 2015 45 Gastroesophageal Intussusception
considered normal for a young puppy. Intestinal parasitism
may also explain the anemia, hypoproteinemia, and lym-
phocytosis; although stress secondary to hospitalization and
illness was suspected to be the primary cause of the white
blood cell abnormalities. Severe vomiting was determined
to be the cause of the hyponatremia, hypochloridemia, and
increased CK. Given the signalment of this case, a predis-
posing congenital disease such as megaesophagus provides
the most likely etiologic diferential for the intussusception.
With the fnding of an adult roundworm in the vomitus,
parasitism as a predisposing condition can also not be ruled
out. Small intestinal intussusceptions have been associated
with parasitism and acute gastroenteritis, both of which could
have played a role in the development of GEI in this puppy
(21). One possible explanation for the development of GEI
in this case is a sudden onset of increased intra-abdominal
pressure caused by vomiting secondary to parasitism, along
with a primary gastrointestinal disease such as congenital
megaesophagus. It is not possible to determine if the mega-
esophagus occurred prior to, or secondary to, the intussuscep-
tion, and, unfortunately, follow up thoracic radiographs were
not obtained to determine if the megaesophagus resolved. To
date, no reports have identifed megaesophagus prior to the
development of GEI.
Dogs with GEI most often present after an acute onset of
esophageal obstruction with regurgitation, vomiting, dyspha-
gia, hypersalivation and abdominal pain. Acute respiratory
distress may also be seen due to a space occupying mass in
the thorax and/or aspiration pneumonia. Cardiogenic or
endotoxic shock due to decreased venous return or gastric
ischemia and necrosis is also possible. Emergency surgery is
usually recommended due to the risk of these severe com-
plications (2, 17).
Laparotomy with bilateral gastropexy is the most com-
monly performed treatment and has been reported to be
successful in preventing recurrence in the majority of cases
(16). Endoscopic replacement has also been described and
can be successful, but some form of gastropexy is required to
prevent recurrence (2).
Prognosis seems to be much better than original reports
indicated, although it remains guarded, particularly with
regard to long term prognosis (2). Prior to 1998, only 3 of
27 (11%) reported cases survived (4). Since that time, more
than 50% of case reports indicate survival with appropri-
ate diagnosis and treatment. Te increase in survival may
be associated with fewer euthanasias or deaths reported,
more prompt diagnosis and treatment, or the use of bilateral
gastropexy as the new treatment of choice.
Diagnosis of GEI is usually made with radiographic
studies, such as thoracic radiography or esophageal contrast
studies.Traditional radiography can be used to provide
strong clinical suspicion, and exploratory laparotomy may
be performed for confrmation. A contrast esophagram will
show a uniformly dilated proximal esophagus with uniform
contrast flling to the gas/soft tissue interface. Te distal
esophagus may or may not contain contrast depending on
how the stomach is positioned within the esophagus and if
contrast can get through the esophageal sphincter. Gastric
rugal folds may or may not be visualized (1). Contrast
radiography can be non-diagnostic and carries the risk of
aspiration of contrast material. Diagnosis of GEI in humans,
along with concurrent treatment, is most often performed
via endoscopy (19). Tis procedure has also been used suc-
cessfully in veterinary medicine for diagnosis and treatment,
particularly in chronic cases (2, 17). Endoscopy, however,
has multiple concerns including: risks of general anesthesia,
specialized equipment that is often not accessible for general
practitioners, need for trained operators, and added expenses.
Te potential advantage of correcting the intussusceptions
at the same time using endoscopes may not be much of an
advantage either, since gastropexy is recommended follow-
ing reduction of the intussusception. Ultrasonography has
been rarely reported as a diagnostic tool for gastroesophageal
intussusception in dogs.
Ultrasound is used frequently in veterinary medicine
for a variety of procedures, particularly for animals with
abdominal disease. It is often useful for patients with a
history of vomiting or related GI disease and is the di-
agnostic method of choice for intestinal intussusceptions
(22). Te characteristic fnding of an intussusception is
the concentric rings or “ring sign” which is created by the
multiple wall layers of the intussusceptum (inner layer) and
intussuscipiens (outer layer) (23). Te intussusceptum is
typically normal in appearance while the intussuscipiens can
have hypoechoic and thickened walls. Te actual appearance
can vary somewhat in diferent patients due to location,
length and type of intestinal segment, and orientation of
the probe. Ultrasonography can also provide additional in-
formation with regard to the presence of additional organ
involvement. In this puppy, the spleen was pulled into the
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Israel Journal of Veterinary Medicine  Vol. 70 (3)  September 2015 Emery, L. 46
distal esophagus via the gastrosplenic ligament. Additional
organs, including the duodenum, pancreas, and omentum,
may be pulled into the esophagus (1, 2). In many cases,
including the current one, the presence of these organs is
likely incidental and emergency surgery is required regard-
less of their involvement. Additional problems, however,
such as torsions, obstructions, and vascular occlusion of
these organs would certainly raise concern for additional
sequelae and possibly decreased prognosis. While contrast
radiography, endoscopy, and ultrasound can all provide a
defnitive diagnosis of gastroesophageal intussusceptions,
ultrasound has multiple advantages including: it is safe and
non-invasive, diagnosis can be obtained very rapidly, it does
not require general anesthesia, it is often readily available
for general practitioners and the cost is reasonable for most
clients. In this case, a diagnosis of gastroesophageal intus-
susceptions was easily made and suggests that this is an
efective tool for diagnosis of this condition.
While this disease remains rare in domestic animals, it is
one that veterinary practitioners should be aware of. It is an
important diferential in young dogs, especially GSD, with
a history of vomiting or regurgitation. Survey radiographs
that show megaesophagus and soft tissue opacity within the
esophagus should increase an index of suspicion for veterinar-
ians. Further diagnostics can be pursued and may include
contrast esophagrams, endoscopy, or ultrasound. Ultrasound
has the advantages of being very rapid, non-invasive, and
readily available for most practitioners, and can provide a
defnitive diagnosis. It does require some familiarity with
ultrasonography, but for those veterinarians with the means
and experience to perform this procedure; this report indi-
cates it to be an efective diagnostic tool.
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