General pathology

Department of Pathology

(Building E/2)

Introduction

Structure of the subject

• General pathology

– 5th semester

– oral exam

• Special pathology

– Bird pathology• 7th semester

• exam (dissection and written exam)

– Mammalian pathology• 6th semester (practical grade)

• (6th and) 8th semester

• final exam (dissection, histopathology, theory)

Dr. Gyula BALKA, PhD, assoc. prof

Dr. Anna SZILASI, assistant professor

Dr. Péter DOBRA, clinical vet.

Dr. Míra MÁNDOKI, PhD, assoc. prof

Lilla DÉNES, PhD-student

Readings

• Lecture notes (!!!)

• General pathology– Robbins & Cotran Pathologic Basis of Disease, 9th edition (2015)

(Robbins Pathology)

– Pathologic Basis of Veterinary Disease Expert Consult, 6th edition(2017) 321 pages

• Special pathology

– Jubb, Kennedy & Palmer's Pathology of Domestic Animals

• 3-Volume Set, 6th Edition (2015) 2456 pages

• Practicals– Vetési, F.: Autopsy of domestic animals

General Information

Practicals:

First practical: meeting at the door of the

students’ entrance with the supervisor

Plastic gloves and plastic shoe covers are required

Exam: semi-final - oral, 3 questions

practical exam on the last practical of the semester

on the 10th of December

(Retake on the 12th of December if needed)

Information:

Szilasi.Anna@univet.hu

Mandoki.Mira@univet.hu

student entrance

Student entrance

Special language

• Learn it, use it!

• „Symptoms” vs „lesions”

• Special expressions

– mean something

– Use „firm”, but not „hard”

– firmly elastic, elasticly firm, …

• Special order of descriptions

– Shape, size, color, palpation, cut surface, ….

The Royal College of Pathologists

„Pathology is the study of disease.

It bridges science and medicine and underpins

every aspect of patient care, from diagnostic

testing and treatment advice to the use of

cutting-edge genetic technologies and the

prevention of disease.

Pathologists work with other doctors,

scientists, nurses and healthcare professionals

in hospitals and GPs’ surgeries (offices) to

diagnose, treat and prevent illness.”

Topics

• 1. Objective, task and investigation

methods of pathology

• 2. Disease

• 3. Death

1., Objectives, tasks and examination

methods of pathology

• Pathology: pathologia

– pathos (suffering) logos (science)

• Science consisting of the study

– of disease (nosologia)

– of defects (defectus)

– of malformations (vitium)

• summarized as study of the functionaland morphological changes in the body during disease

• Diagnostic pathology an autopsy (syn: necropsy) may be

performed to determine the cause of death in an individual

or in a group of animals or to explain decreased

production

• Forensic pathology the purpose of an autopsy is to

determine the nature of death from a legal perspective

• Surgical pathology (histologic examination of surgically

excised tissue specimens) not only facilitates diagnosis

and prognosis for a living animal but also can be the basis

for therapy

• Experimental pathology contributes from the design to

the end point of an investigation with the goal of

correlating morphologic changes with clinical, functional,

and biochemical parameters to elucidate the mechanisms

of disease

• Comparative pathology compares specific human

pathologies with those seen in natural animal models

(tuberculosis, anthrax, erysipelas etc.)

Disease

1., Functional changes

( Pathophysiology)

2., Morphological changes

( Pathology)

Morphological examinations

Both can be cause and

consequence of the other

Basis of other subjects (Infectious

diseases, Veterinary forensic

medicine, Food hygiene etc.)

Methods to recognize/investigate the

disease:

1., Autopsy (sectio cadaveris)

History: prehistoric, ancient and new

times

Tools: knives, scissors, saw etc.

Autopsy, necropsy

• Dissection of the carcass

• Using our sensory organs

– Vision

– Palpation

– Smelling

– Hearing

• Collect the visible changes

– Macroscopic examination

• Fotodocumentation

In certain cases autopsy itself reveals the cause of death

„Pathognomic changes” (heart infarct, pyonephros, gastric torsion,

intestinal rupture etc.)

In the vast majority of the cases complementaryinvestigations are necessary!

Rupture of the large intestine, horse

When autopsy is not enough supplementary

investigations

1., Histopathology:

• investigation using light microscope, mostly on FFPE

(formaldehyde fixed, paraffine embedded) tissues

• Haematoxylin and eosin

• Special staining methods

Ziehl-Neelsen staining

Perl’s staining

2., Immunohistochemistry (IF, IPO), in situ hybridisation

Rotaviral infection

(calf, intestinal epithel)

MAC-387

MAC-387

3., Electron microscopic investigations

4., Toxicological, parasitological, bacteriological,

virological investigations

4., Molecular biological investigations, PCR, sequence

determination, next generation sequencings

Cycle

5 10 15 20 25 30 35 40 45

Norm

. F

luoro

.

0,25

0,20

0,15

0,10

0,05

0,00

Threshold

(Trichoblastoma, basalioma)

Post-mortem and ante-mortem investigations (excision, fineneedle aspirate, biopsy samples from living animals)

Individual and herd diagnosis (infections, parasitoses, toxicoses), prevention of epidemics, mass infections

Pathogenesis (how does the disease proceed)

Comparative pathology (different species, humans zoonoses) tuberculosis, anthrax, erysipelas

Foot and mouth disease in cattle,

pig and human

General pathology: study of the reaction of cells or tissues to injury with a focus on the mechanisms of that response. Basic changes

– Circulatory disturbances

– Regressive changes

– Proliferative changes

– Inflammations

– Tumors

– Developmental anomalies

Special pathology/systemic pathology: characteristic changes caused by well defined diseases, grouped according to organ systems

“Nosos” - differs from the normal. Border between normal and abnormal? (Deviation from average can be normal)

Body temperature, heart beat, erythrocyte number etc.

Malformation (vitium), defect

(defectus) - not normal, but isn’t a

disease (i.e. polydactylia)

Oligodontia

2. Disease

• Vital functions differ pathological change develops.

• Disease is a dynamic process. Functional changes (AIDS). Not always visible!

infectionvirus carrier

status

clinical symptoms

death

Incubation time

Groups according different

characteristics• Diseases are diverse

• Localisation, extension

– general, organ and systemic diseases

• Aetiology:

– Infectious (morbidity, mortality, lethality)

• Spreading: endemic, epidemic, pandemic

• Agent: bacterial, viral, fungal, parasitic

– Non infectious

• Appearance: continous, periodic, paroxysmal

• Duration: foudroyant, peracute, acute, subacute, chronic

Followed by recovery (sanatio) or death (exitus lethalis).

Short recovery: remission (remissio) recurrence (recidiva)

Healing (sanatio):

• Mild degree of functional changes, reversible morphological alterations revivification (recreatio)

• Complete recovery following more profound tissue alterations, lost cells are replaced by corresponding tissues regeneration (regeneratio)

• Tissue alterations replaced by

connective tissue repair

(reparatio, organisatio)

• Localisation of necrotic parts

(demarcatio)

Demarcation (abscesses in the lung, horse)

Complete recovery (restitutio ad integrum)

Permanent morphological or structural changes (restitutio

cum defectu) locus minoris resistentiae

3. Death

“Mors” Irreversible cessation of life of the whole organism (different than necrosis)

Natural and pathologic ( disease) death. Aging, senescence (gerontology) senile atrophy (dissimilation > assimilation, decreasedhormone production, adaptability, immune response, healing etc.) Enhanced sensitivity to diseases. Natural lifespan is variable (optimal conditions).

“Atria mortis”: brain, heart, lungs.

• Sudden death (mors subita)

• Agony (Euthanasia!)

Death struggle

loss of senses, constrictions, convulsions CO2 final relaxation of muscles

Clinical death (no breathing, no heartbeat, but tissues and

organs survive for a while resuscitation, grafts,

transplantation, culturing) pathological agony

(„intermediate life”) pathological or absolute death

Recognition of death: no heartbeat, no responses to sensory or sensitive stimuli, no reflexes (pupils „brain death”) when post mortemchanges start: obvious