Equine Internal Medicine : Self-Assessment Color Review Second Edition

394 Pages·2015·35.932 MB·English

by  Divers, Thomas J., Mair, Tim S

Self-Assessment Color Review
Equine Internal Medicine
Second Edition
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Self-Assessment Color Review
Equine Internal
Medicine
Second Edition
Tim S. Mair
BVSc, PhD, DipECEIM, MRCVS
Bell Equine Veterinary Clinic
Maidstone, UK
Thomas J. Divers
DVM, DACVIM, DACVECC
College of Veterinary Medicine
Cornell University, Ithaca, USA
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CRC Press
Taylor & Francis Group
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© 2016 by Taylor & Francis Group, LLC
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Version Date: 20150519
International Standard Book Number-13: 978-1-4822-2537-2 (eBook - PDF)
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Preface
This book presents to its readers two hundred and one interesting and challenging
clinical cases from our files. Most cases are accompanied by photographs of the
horses, imaging or endoscopy findings, blood or fluid smears, other ancillary tests
and, in some cases, pathologic findings. We ask pertinent questions with each case
to help guide the reader through the case workup and treatments. In-depth answers
for each case are provided in the second half of the book. All the cases are new
to this second edition. We have included for most cases a brief discussion of each
patient’s disease and one or more pertinent references. The majority of our cases
are disorders that may be found in both North America and Europe. However,
a small number of cases unique to only one of these two continents are included
because they represent important or common diseases on that particular continent.
We take this opportunity to thank Jill Northcott, editor at CRC Press, and her staff
for their excellent work in preparing our reports and photographs for publication.
Special thanks to Drs. Nora Grenager and Eva Chase Conant for reviewing and
editing the scientific content of each case; their help was invaluable. Additional
thanks go to internal medicine colleagues at Cornell University (Drs. Ainsworth,
Perkins, and Felippe) and to veterinarians who completed their internal medicine
residencies at Cornell University, provided several of the photographs and valuable
information for use in the book, and assisted with the management of the cases:
Drs. Monica Figueiredo, Rachel Gardner, Jen Gold, Amy Johnson, Alexa Burton,
Katharyn Mitchell, Terri Ollivett, Toby Pinn, Dominic Dawson, Katie Mullen,
Sally Ness, and Emily Barrell. We also wish to acknowledge and thank Drs. Laura
Stokes-Green, Joy Tomlinson, Ashley Watts, Emily Barrell, and Ed Jedrzejewski
for the information and photographs on cases 46, 78, 2 and 70, 105, and 86,
respectively. We also thank colleagues and previous interns and residents at Bell
Equine Veterinary Clinic, especially Ceri Sherlock and Edd Knowles.
Special thanks are due to Dr. Keith Montgomery, former ophthalmology resident
at Cornell, who supplied the “what’s your diagnosis” ophthalmology cases that are
placed throughout the text.
We hope you will find these case presentations interesting, challenging, and of
educational value.
Tim S. Mair
Thomas J. Divers
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Dedication
This edition of Equine Internal Medicine: Self-Assessment Color Review is
dedicated to T. Douglas Byars, DVM, DACVECC, DACVIM, who passed away
in July 2014 after a prolonged illness. Dr. Byars was a legend in equine internal
medicine and known around the world as the “go to person” for consultation on
serious or complicated medical illnesses in the horse. Dr. Byars, although based
in Lexington, Kentucky, spent a considerable amount of time traveling to Europe
and elsewhere in the world to consult on difficult medical cases. He also spent
innumerable hours on the phone with veterinarians worldwide offering advice on
cases. Many cases in this current Equine Internal Medicine text would be similar
to cases Dr. Byars was frequently asked to treat or consult on.
Dr. Byars was ‘The Internist’ in the United States most responsible for leading
equine internal medicine diplomates into private practice. He was the first board-
certified veterinary internist to leave a university practice and develop the highly
successful private practice equine internal medicine hospital, now known as the
Hagyard Medical Institute. Doug worked at Hagyard’s for nearly 25 years and
his success in that internal medicine specialty practice opened the doors for other
internists in the Lexington area and throughout the world. For this and many other
services to veterinary internal medicine, Doug was in 2007 awarded the Robert W.
Kirk Award by the American College of Veterinary Internal Medicine (ACVIM), the
highest award given to any veterinary internist (large or small animal). Dr. Byars
should also be credited for developing the equine specialty area in the American
College of Veterinary Emergency and Critical Care (ACVECC); he was one of the
initial three, exam-boarded diplomates in that College. His pursuit of critical care
specialty training developed because of his realization that his practice was as
much about critical care as it was internal medicine.
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Dr. Byars was a staunch believer in being a voice for the horse and always
wanted to do what was best for every horse. During his last year of life, his work
was mostly limited to caring for retired Thoroughbreds. When asked to take that
last job, he was told he would not be called at night; Doug’s response was “I will
only take the job if you do call me at night when a horse needs my help.” Doug was
a strong promoter of the entire horse industry, a great and trusted friend of many
horse owners and trainers and a mentor to many young veterinarians finding their
way in equine practice. Although his work was mostly in hospital-based practice,
Doug always made an effort to visit farms to follow up on his cases and to spend
time with the farm managers and the stable hands that cared for the horses. He
was a good and dedicated friend to all, caring for people but caring as much for
horses. His professional ethics and morals were unquestionably strong; anyone,
regardless of their wealth or status, who suggested a less than ethical approach to
a case would immediately experience an angered Dr. Byars.
Doug was a trusted and true friend to both authors of this book and to hundreds
of veterinarians worldwide. We learned so much from him and we laughed a lot
together over many years. We and many other veterinarians worldwide would like
to say “thank you Doug, you are greatly missed!”
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Abbreviations
AKI acute kidney injury (formerly IV intravenous/intravenously
acute renal failure) MIC mean inhibitory concentration
AST aspartate aminotransferase MPV mean platelet volume
bpm beats/breaths per minute MRSA methicillin-resistant
BCS body condition score Staphylococcus aureus
BUN blood urea nitrogen NSAID non-steroidal anti-
CBC complete blood count inflammatory drug
CK creatine kinase OD oculus dexter (right eye)
CN cranial nerve OS oculus sinister (left eye)
CNS central nervous system OU oculus uterque (both eyes)
Cr creatinine PaCO partial pressure of arterial
2
CRI constant rate infusion carbon dioxide
CRT capillary refill time PaO partial pressure of arterial
2
CSM cervical stenotic myelopathy oxygen
CT computed tomography PCV packed cell volume
DIC disseminated intravascular PMN polymorphonuclear neutrophil
coagulation PO per os, orally
ECG electrocardiogram PvO partial pressure of venous
2
epg eggs per gram oxygen
EPM equine protozoal RBC red blood cell
myeloencephalitis RR respiratory rate
GA general anesthesia SC subcutaneous/subcutaneously
GI gastrointestinal SG specific gravity
HPA hypothalamus/pituitary/ SvO venous oxygen saturation
2
adrenal (axis) TP total protein
HR heart rate TPN total parenteral nutrition
IM intramuscular/intramuscularly TS total solids
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