THE ULTRASONOGRAPHIC APPEARANCE OF THE GASTROINTESTINAL TRACT IN NORMAL ...

86 Pages·2010·5.39 MB·English

THE ULTRASONOGRAPHIC APPEARANCE OF THE
GASTROINTESTINAL TRACT IN NORMAL AND
PARVOVIRAL INFECTED PUPPIES

by

Nerissa Stander

Submitted to the Faculty of Veterinary Science, University of
Pretoria, in partial fulfilment of the requirements for the degree
MMedVet (Diagnostic Imaging)

Pretoria, October 2009
©© UUnniivveerrssiittyy ooff PPrreettoorriiaa
PROMOTER
Dr Amelia Goddard
Department of Companion Animal Clinical Studies
Faculty of Veterinary Science
University of Pretoria

ii
To Braham

iii
TABLE OF CONTENTS

Acknowledgements vii
List of Figures viii
List of Tables ix
List of Appendices x
Summary xi

CHAPTER 1 INTRODUCTION

1.1 Background 1
1.2 Problem statement 1
1.3 Hypothesis 2
1.4 Objectives 2
1.5 Benefits 3

CHAPTER 2 LITERATURE REVIEW

2.1 Ultrasonography of the normal canine gastrointestinal tract 4
2.2 Ultrasonography of gastrointestinal disease 7
2.3 Ultrasonography of paediatric patients 9
2.4 Canine parvoviral infection 10
2.5 Diagnostic imaging of canine parvoviral infection 12
2.6 Conclusions drawn from the literature review 14

iv
TABLE OF CONTENTS

CHAPTER 3 MATERIALS AND METHODS

3.1 Experimental design 15
3.1.1 Normal puppies 15
3.1.2 Puppies with parvoviral enteritis 15
3.2 Experimental procedures 16
3.2.1 Normal puppies 16
3.2.2 Puppies with parvoviral enteritis 16
3.2.3 Clinical score 17
3.2.4 Ultrasonographic examination 17
3.2.5 Histopathology 20
3.3 Data and statistical analysis 20
3.4 Ethical considerations 21

CHAPTER 4 RESULTS

4.1 Normal puppies 22
4.1.1 Ultrasonographic findings 22
4.2 Puppies with parvoviral enteritis 26
4.2.1 Ultrasonographic findings 26
4.2.2 Clinical outcome and correlation with ultrasonographic findings 33
4.2.3 Histopathology findings in two puppies 34

v
TABLE OF CONTENTS

CHAPTER 5 DISCUSSION

5.1 Ultrasonography of normal puppies 39
5.1.1 Gastrointestinal tract 39
5.1.2 Peritoneal fluid 40
5.1.3 Jejunal lymph nodes 41
5.1.4 Limitations of the study 41
5.2 Ultrasonography of puppies with parvoviral enteritis 42
5.2.1 Gastrointestinal tract 42
5.2.2 Peritoneal fluid 44
5.2.3 Jejunal lymph nodes 44
5.2.4 Clinical correlation with ultrasonographic findings 44
5.2.5 Correlation with histopathology 45
5.2.6 Limitations of the study 45
5.3 Future studies 46

CHAPTER 6 CONCLUSION 47

REFERENCES 48

APPENDICES 54

vi
ACKNOWLEDGEMENTS

I would like to thank the following people for their help without which this project would
not have been possible:

Dr Amelia Goddard, my promoter for her never ending enthusiasm and encouragement.

Prof. Peter Thompson for the statistical analysis.

The Onderstepoort Teaching Animal Unit (OTAU) for the use of the Beagle puppies.

Sr. Anette van Veenhuysen for holding the Beagle puppies during the ultrasound
examinations.

Sr. Mandy Wielopolska and the staff and students of the Onderstepoort Veterinary
Academic Hospital Isolation Unit for their assistance in recruiting subjects as well as for
holding the parvoviral infected puppies during the ultrasound examinations.

Mrs. Erna van Wilpe and the technicians at the Electron Microscopy Unit for performing
the faecal electron microscopy.

Drs. June Williams and Sarah Clift for conducting the post mortem examinations.

My husband, Braham for his support and for holding the parvoviral infected puppies for
me on weekends albeit clad in gloves, gown and mask for fear of catching something
contagious!

And lastly, my father and role model, Prof. Robert Kirberger for inspiring me to become
a radiologist – May I one day have your knowledge!

vii
LIST OF FIGURES

FIGURE 1 Correlation between the histological structure of the normal canine 13
duodenal wall with the layers seen on ultrasound images

FIGURE 2 Mild amount of anechoic free peritoneal fluid seen in normal puppies 21

FIGURE 3 Jejunal lymph node in an 11-week-old healthy Beagle puppy 22

FIGURE 4 Appearance of wall layering in various gastrointestinal segments 23

FIGURE 5 Box and whisker plots representing the wall thicknesses of the 25
various gastrointestinal segments in normal puppies relative to each
other

FIGURE 6 Sloughed jejunal mucosa in a puppy suffering from parvoviral 26
enteritis

FIGURE 7 Box and whisker plots representing the mean thickness of the 27
duodenal and jejunal mucosal layers in normal vs. parvoviral infected
puppies

FIGURE 8 Multiple fluid distended jejunal loops typically seen in canine 28
parvoviral enteritis

FIGURE 9 Corrugated duodenum and jejunum in a puppy suffering from 30
parvoviral enteritis

FIGURE 10 Duodenal wall of a puppy suffering from parvoviral enteritis vs. a 31
normal 8-week-old Beagle puppy

FIGURE 11 Jejunal mucosal changes seen in canine parvoviral infection 31

FIGURE 12 Essentially normal histopathology section of the stomach of a puppy 33
suffering from parvoviral enteritis

FIGURE 13 Histopathology sections of a duodenum affected by canine parvovirus 34

FIGURE 14 Histopathology sections of a jejunum affected by canine parvovirus 35

FIGURE 15 Histopathology sections of an ileum affected by canine parvovirus 36

FIGURE 16 Histopathology sections of the cortex of a normal jejunal lymph node 37
and that of a jejunal lymph node affected by canine parvovirus

viii
LIST OF TABLES

TABLE 1 Ultrasonographic gastrointestinal measurements in normal puppies 22

TABLE 2 Ultrasonographic gastrointestinal measurements in canine parvoviral 26
infected puppies vs. normal puppies

TABLE 3 Results of analysis of ultrasonographic descriptive parameters for 30
canine parvoviral infected puppies

TABLE 4 Correlation between clinical score, intestinal corrugation and 32
mucosal changes in parvoviral infected puppies with clinical scores
of ≤ 14

ix
LIST OF APPENDICES

APPENDIX A Client consent form 54

APPENDIX B Client information sheet 56

APPENDIX C General treatment guidelines for canine parvoviral enteritis 58

APPENDIX D Additional information sheet 60

APPENDIX E Clinical scoring assessment 61

APPENDIX F Ultrasound examination form 63

APPENDIX G Results datasheet for normal puppies 65
Age, weight, sex and findings of clinical examination

APPENDIX H Results datasheet for normal puppies 66
Ultrasonographic measurements

APPENDIX I Results datasheet for puppies with parvoviral enteritis 67
Age, weight, sex and breed

APPENDIX J Results datasheet for puppies with parvoviral enteritis 68
Clinical score, biochemical parameters and patient outcome

APPENDIX K Results datasheet for puppies with parvoviral enteritis 70
Ultrasonographic measurements

APPENDIX L Results datasheet for puppies with parvoviral enteritis 72
Ultrasonographic descriptive parameters

APPENDIX M Results datasheet for puppies with parvoviral enteritis 74
Correlation between clinical score, intestinal corrugations and
mucosal changes

x