laboratory vet tech prep power pages

Diabetes mellitus

a common endocrine problem in dogs and cats caused by inadequate insulin production of peripheral insulin resistance.

key clinical signs of diabetes mellitus

PU/PD,

polyphagia

and weight loss

Less common clinical signs of diabetes mellitus

plantigrade stance (cat)

and cataracts (dog)

Diabetes mellitus type 1

pancreas is no longer producing insulin

diabetes mellitus type 2

caused by insulin resistance (rare in the dog, more common in the cat);

if treated properly, some cats may actually go into diabetic remission

there are 2 presentations of diabetes mellitus:

healthy diabetic or diabetic ketoacidosis

diabetes mellitus: healthy diabetic clinical signs

● PU/PD (polyuria and polydipsia)

● Polyphagia (increased appetite) and weight loss

● Recurrent infections

● Plantigrade stance from diabetic neuropathy (cats)

● Cataracts (dogs)

diabetes mellitus: diabetic ketoacidosis (DKA) clinical signs

● Anorexia

● Vomiting

● Weakness

● Metabolic acidosis

● Blood glucose > 500 mg/dl

● May have previous history of the signs of a "healthy diabetic"

what diagnoses diabetes mellitus

based on clinical signs and bloodwork analysis with urinalysis

hyperglycemia can diagnose diabetes mellitus this is

often >300mg/dl

NOTE: stress can cause hyperglycemia particularly in cats

what else can diagnose diabetes mellitus?

● Glucosuria +/- ketonuria

○ NOTE: While less common, stress in cats can also cause glucosuria

Ancillary tests of fructosamine and glycosylated hemoglobin reflect

the patient's blood glucose levels over several weeks

treatment of diabetes mellitus mainly includes

insulin injections most often given twice daily subcutaneously at home by the owner

what diet changes are recommended for diabetes mellitus patients

A high fiber, low fat diet (dogs) or high protein, low carb diet (cats) is recommended

types of insulin

-short acting

-intermediate or long acting insulin

-peakless insulin

short acting insulin

Humulin R

What insulin is most often used in cases of diabetic ketoacidosis (DKA)

short acting insulin (Humulin R)

ketoacidosis (DKA) ○ Intermediate-or longer-acting insulins

Humulin-N, Vetsulin

Peakless insulin

Glargine (lantus)

Peakless insulin is used in

cats

in horses, internal parasites can cause significant health problems in horses such as

-weight loss

-diarrhea

-colic

-chronic weight loss

horses GI parasites are

-strongyles. Divided into small vs large

-Anoplocephala perfoliata -equine tapeworm

-Parascaris equorum- equine roundworm

large strongyles

-Strongylus vulgaris

-Strongylus edentatus

-Strongylus equinus

The adult strongyles are located within the

cecum and colon of infected horses.

Strongyles in horses may also

migrates throughout host tissues during the developmental stages resulting in damage to various organs

Strongylus vulgaris (lg) is most commonly associated with

clinical signs of disease; however, with the advent of modern anthelmintics, colic as a result of S. vulgaris is fairly infrequent.

strongylus vulgaris (lg) Larvae route of travel

they penetrate submucosal arteries and migrate along endothelium to the cecal and colic arteries and then to the base of the cranial mesenteric artery; they return to the intestine via the arteries.

As strongylus vulgaris (lg) parasites migrate through mesenteric arteries, they can cause

thrombosis, inflammation and infarction with subsequent necrosis of the intestine.

Strongylus edentatus (lg) larvae route of travel

Larvae invade gut wall, penetrate blood vessels and migrate to liver via the hepatic portal vein; larvae then travel through the liver and return to the large intestine via the mesentery.

● Migration may or may not result in observable clinical signs.

Strongylus equinus (lg) larvae route of travel

● During maturation, larvae leave the intestine and migrate to the liver; from there they migrate back to the large intestine

. ● Migration may or may not result in observable clinical signs.

equine tapeworm scientific name

Anoplocephala perfoliata

the equine tapeworm may be a

common cause of colinc

the equine tapeworm inhabits

the region of the ileocecal junction and can produce ulcerations of the mucosa.

equine roundworm scientific name

Parascaris equorum

equine roundworms mainly affect what age

foals, not a significant parasite in the adult horse

adult horses develop immunity to

roundworms

Disease from roundworms in foals results in

ill thrift and poor weight gain, but can also result in significant disease from such a heavy burden of large worms resulting in intestinal impaction

small strongyles

Cyathostomes spp

small strongyles include over

40 species

Small strongyles cause

severe diarrhea in adult horses (larval cyathostomiasis)

severe diarrhea in adult horses from small strongyles

larval cyathostomiasis

larval cyathostomiasis typically occurs in what seasons

the late winter or spring

-is associated with the simultaneous emergence of a large number of fourth-stage larvae from the intestinal mucosa.

larval cyathostomiasis rapid emerge can lead to

significant diarrhea, weight loss, hypoproteinemia and possibly death

Equine Lung Worm

Dictyocaulus arnfieldi

the equine lung worm is commonly observed in

Donkeys but they rarely produce clinical signs

the suspected natural host/ inapparent carriers of equine lungworm are

donkeys.

how do horses get equine lungworm

the horses acquire it through contact with donkeys or their pastures.

symptoms of equine lungworms

bronchial inflammation and chronic cough

the equine lungworm can grow up to

16cm

what parasite that is not a lung worm can migrate through the lung and produce signs of resporatory disease

equine lungworm can do this in foals

Macrocyclic Lactones

Ivermectin Moxidectin

Macrocyclic Lactones treats what in horses

-adult large strongyles

-migrating large strongyle larvae

-Cyathostomes- adult small strongyles

Ascarids-roundworms

Bots

Benzimidazoles

Fenbendazole

Oxfendazole

Mebendazole

Macrocyclic Lactones mode of action

Affect glutamate-gated chloride channels

Benzimidazoles mode of action

Beta-tubulin binding and inhibition of microtubule formation

Benzimidazoles treat what in horses

-adult large strongyles

-migrating large strongyle larvae

-Cyathostomes- adult small strongyles

Ascarids-roundworms

Bots

Pyrimidines

Pyrantel pamoate

Pyrantel tartrate

Pyrimidines mode of action

Cholinergic effect on parasite ganglia

Pyrimidines treat what in horses

adult large strongyles

-Cyathostomes- adult small strongyles

Ascarids-roundworms

Heterocyclics

Piperazine

Heterocyclics mode of action

neuromuscular hyperpolarization

heterocyclics treat what in horses

adult large strongyles

-Cyathostomes- adult small strongyles

Ascarids-roundworms

Pyrazinoisoquinolines

Praziquantel

treat what in horses

tapeworms

what dewormer classes are used in horses

Macrocyclic Lactones

Benzimidazoles

Pyrimidines

Heterocyclics

Pyrazinoisoquinolines

CBC

complete blood count

RBC count

the number of RBC's per microliter of whole blood

Hemoglobin (Hgb) measurement

Grams of hemoglobin per microliter of whole blood

Hematocrit (Hct) measurement

percentage of whole blood volume composed of RBCs

MCV (mean corpuscular volume)

Average size of red blood cells in femtoliters (a femtoliter is 1 x 10^-15 liters)

used with hematocrit measurement

RBC distribution width (RDW)

Percent variation in size of the RBC population

Mean Corpuscular Hemoglobin (MCH)

Average weight of hemoglobin per RBC in picograms

Mean Corpuscular Hemoglobin Concentration (MCHC)

Average concentration of hemoglobin per RBC in grams per deciliter

WBC count

The number of WBCs per microliter of whole blood

Differential count

thie percentage and absolute number of each WBC

WBC's

○ Neutrophils (also known as "Segs")

○ Lymphocytes

○ Monocytes

○ Eosinophils

○ Basophils

platelet count

the number of platelets per microliter of whole blood

Mean Platelet Volume (MPV)

Average size of platelets in femtoliters

Anemia

decreased number of red blood cells

Polycythemia

increased number of red blood cells

Rouleaux formation

red blood cells that form stacks

agglutination

RBC's that form irregular clumps

microcytosis

decreased red blood cell size

macrocytosis

increased RBC size

Anisocytosis

increased variation in cell size

hypochromia

(cell color)

decreased pigment (increased pallor)

Hyperchromia

(cell color)

increased pigment (lack of central pallor)

Anisochromasia

(cell color)

Increased variation in pigmentation

polychromasia

(cell color)

RBC's with a blue or lilac tinge

Poikilocytosis

increased variation in RBC shape

(cell shape)

Spherocytosis

cells that are spherical in shape with lost central pallor

(cell shape)

target cell

cell with strongly staining area in the middle of the central pallor region

(cell shape)

Schistocyte

fragmented RBCs that are usually angular

(cell shape)

Echinocyte

-burr cell/crenated

-RBC with many (20-30) small, regular, blunt projections

(cell shape)

Acanthocyte

cell with irregularly distributed small projections

(cell shape)

Howell-Jolly bodies

round dense staining inclusions, usually toward one edge of the cell; represents a nuclear fragment

(RBC inclusions)

Basophilic stippling

(RBC inclusions)

the presence of small basophilic inclusions distributed throughout the RBC; represents abnormally staining ribosomes

Nucleated RBCs (nRBCs)

(RBC inclusions)

RBC's that have not completed maturation and still have a nucleus

Cytoplasmic basophilia

Toxic changes in neutrophils

- streaky diffuse blue appearance to cytoplasm

Dohle bodies

Toxic changes in neutrophils

-round to linear blue aggregates in the cytoplasm