Democisosis Flashcards
Temporary immune alteration- young dogs
name changes
Normal humoral response, but decreased lymphocyte blastogenesis
Low number of circulating CD4+ T cells
Increased serum concentrations of IL-2, IL-5, IL-6, IL-18, IL-10, TGF-𝛃
Decreased TNF-𝝰
CD4:CD8 ratio was lower
Increased number of CD8 + cells (mural folliculitis with infiltrating CD8+ cytotoxic T cells)
MHC class II receptors are upregulated
Pit bull terriers: significant higher serum IgA, IL-2, IL-18 and monocyte chemoattractant protein-1
Increased TLR-2, and decreased TLR-4 and TLR-6
Increased markers of oxidative stress
Name diseases associated with demodicosis in dogs
DOGS: leishmaniosis, hyperadrenocorticism, hypothyroidism, neoplasia, babesiosis, ehrlichiosis, glucocorticoid treatment, chemotherapy, AD
Name diseases associated with demodicosis in cats?
CATS: FIV, xanthoma, DM + localized in scc
In humans, demodicosis is associated with?
Hereditary T cell defect or due to immunosuppression
Name breeds predisposed for generalized demodicosis (4-fold increased risk):
American Staffordshire terrier, Staffordshire bull terrier, Chinese shar-pei, French bulldog
Name breeds predisposed for juvenile onset demodicosis?
English bulldog, pit bull, Sealyham terrier
Name genes that have significant association with generalized demodicosis
DLA haplotypes FH2002, FH2975, FH2054 in Argentinian mastiffs and boxer dogs
Name demodex species found in dogs?
Demodex canis
D. injai
+ D. cornei- short bodied mite, some believe it is a morphological variant od D. canis or dead or near dead D. canis mites, BUT taxonomic analysis revealed to be a distinct canine species
Name demodex species found in cats?
D. cati
D. gatoi (contagious, regional in South-eastern USA)
+ 3rd unnamed species (has longer gnathosoma, shorter opisthosoma than D. cati, the length: width ratio of the opisthosoma is 2:1, in D. cati is 5:1)
Name clinical signs of demodicosis?
Noninflammatory hypotrichosis/alopecia, erythema, comedones, scaling, hyperpigmentation, edema, pain, pruritus, follicular casts , follicular pustules, furunculosis, exudation and ulceration with draining tracts
+SYSTEMIC: lymphadenopathy, lethargy, fever, septicemia , death
In which dog breeds is D. injai overrepresented and what is its most striking clinical feature?
In terrier breeds and their crosses
Marked greasiness of the dorsal trunk
Which environmental factors have been discussed to lead to more severe clinical signs in the dog ?
High humidity and ambient temperature
Name clinical symptoms found in cats ?
Erythema, hypotrichosis/ alopecia, scale, crusting, variable pruritus
Which part of the skin inhabits D. gatoi, name symptoms found in D. gatoi infestation and name site of predilection?
Contagious mite that inhabits stratum corneum
Most common symptom is pruritus, self-induced alopecia, scale, 2nd hyperpigmentation, erosions and ulcerations
Changes are predominantly seen in truncal part with the ventral abdomen being predilection site
Name all diagnostic procedures for diagnosing demodicosis
Deep skin scrapings
Trichograms
Tape strips (scotch tape test)
Skin biopsy
Other: direct examination of the exudate from pustules or draining tracts, cytology, faecal flotation
What is amitraz and most common side effects seen in dogs and humans?
Amitraz is a monoamine oxidase inhibitor, alpha 2-adrenergic agonist and inhibits prostaglandin synthesis
Side effects in dogs: depression, sleepiness, ataxia, pruritus, urticaria, edema, skin irritations, polyphagia, PD, hypotension, bradycardia, hyperglycaemia, vomiting, diarrhoea
Side effects in people: altered sensorium, miosis, hyperglycaemia, bradycardia, vomiting, respiratory failure, hypotension, hypothermia, DIABETIC should avoid all contact!!
Name antagonists for amitraz poisoning?
Yohimbine and atipamezole
Name dog breeds in which amitraz should be avoided?
Chihuahuas and Pomeranians
Name recommended concentration of amitraz for treatment
0.025-0.06 % once weekly to every 2 weeks
Intensive protocol daily rinsing (half of the body) 0.125%
Intensive weekly 1.25% + atipamezole 0.1 mg/kg im, yohimbine 0.1 mg/kg po 3 days
Name from which soil bacteria ivermectin comes?
Streptomyces avermitilis
Dose of ivermectin that is recommended?
300-600 µg/kg PO SID 4-8 weeks beyond parasitological cure (labelled only for prevention of Dirofilaria immitis)
Name dog breeds sensitive to ivermectin’s?
Collie breeds, Australian shepherd dogs, Shetland and old English sheepdogs
Most common signs of ivermectin toxicosis?
Mydriasis, lethargy, vomiting, ataxia, tremors, temporary blindness, seizures, stupor, coma, respiratory failure, death
Name gene responsible for ivermectin sensitivity ?
ABCB1 gene (former mdr1)
Name antidote for ivermectin?
There is no antidote !
What are the treatment recommendations in case of overdose with ivermectin?
Repeated doses of charcoal
Intravenous lipid emulsion (effects is due to lipid sink mechanism whereby drug is drawn out of the tissues and sequestered into a lipid phase within the intravascular phase, thereby decreasing CNS tissue concentrations)
PHYSOSTIGMINE (parasympathomimetic alkaloid, reversible cholinesterase inhibitor, cause short term improvement in neurological signs)
FLUMAZENIL (GABA antagonist, reverses effects of ivermectin in mice, in dogs has to be determined)
How does the mutation on ABCB1 causes problems with P-glycoprotein and what is a P-glycoprotein?
It is an ATP-dependent transmembrane transporter protein
Deletion mutation causes P-gp synthesis to terminate prematurely and resulting in truncated, non-functional P-gp molecules
Transport of certain drugs OUT of the CNS is impaired and results in accumulation of drug within CNS to toxic level
How long is ivermectin half-life?
80± 30h !
Name bacteria from which milbemycin oxime is fermented?
Streptomyces hygroscopus aureolacrimosus
For what is milbemycin licenced and at what dose?
For endoparasites
Demodicosis at 1-2 mg/kg sid
Can dogs with ABCB1 mutation take milbemycin ?
Yes, but homozygous dogs develop ataxia with higher end dosages
Which route of administration is the most effective for moxidectin?
SC, but topical is the safest
Name side effects when using moxidectin?
Emesis, salivation, anorexia, lethargy, dyspnoea, facial edema
At which dose doramectin is used and name side effects ?
Doramectin 600 µg/kg weekly SC
Ataxia and local irritation reaction at the injection site
Name ectoparasiticides that belong to isoxazolines group?
Fluralaner, lotilaner, sarolaner, afoxolaner
How does the isoxazolines work?
They target a binding site that inhibits insects and acarine ligand-gated chloride channels , particularly gated by GABA
They block pre- and postsynaptic transfer of chloride ions across cell membranes
Prolonged isoxazoline -induced hyperexcitation results in uncontrolled activity of the CNS and death of insects and acarines
Can fluralaner given to MDR1 dogs?
yes
What is the recommended dose for fluralaner and weight /age ?
25-56 mg/kg every 3 months
Healthy dogs 8 weeks or older and weighing ≥ 2 kg
What are side-effects of fluralaner usage and in which disease is to be used with caution?
Vomiting, anorexia, diarrhoea, lethargy, PD, flatulence
To be used with caution pre-existing epilepsy
What side effects have been reported with afoxolaner (Nexgard) and afoxolaner and milbemycin (Nexgard spectra) ?
Vomiting, diarrhoea, dry flaky skin, anorexia, lethargy, SEIZURES
What is the recommended dose of afoxolaner?
2.5-2.7 mg/ kg monthly
What is the recommended dose of lotilaner (Credelio)?
20 mg/kg
Name other drugs mentioned in the literature for treating demodicosis (which are not recommended for treatment)?
Muramyl dipeptide (0.2 mg/kg sc weekly) ± amitraz (0.025% and 0.05% twice weekly)- increases lymphocyte response to mitogens
Levamisole (3-10 mg/kg)- had positive effect on lymphocyte proliferation assay, but didn’t improve efficacy
Amitraz rinses 0.0375% every 5 days ± 2 ml of inactivated Parapox virus suis SC on days 0,2,9
Vitamin E 1000 mg daily PO + weekly amitraz rinses 0.05%
Lufenuron (chitin synthesis inhibitor) 15.8 mg/kg 3 times weekly- no effect
Deltamethrin spray 0.005 % 3 weekly applications- no effect
Deltamethrin 12.5% vs. Oleum pinus, Oleum terebinth, Mallotus phillipensis, Sulphur sublimatum BID
Homeopathic preparations containing Sulphur 200, Heparsulphurius 200, Psorinum 200 PO 5 drops-variable results
Herbal preparations containing extracts of cedrus deodara, Azadirecta indica, Embelia ribes
Closantel (anthelminthic)
Name recommended treatment options for cats
Weekly lime sulfur dips 2%
Amitraz baths 0.0125%
Weekly administration of moxidectin/imidacloprid
In the literature also: oral fluralaner, organophosphate baths, rotenone, ivermectin, selamectin, milbemycin oxime
How demodex mites influence normal microbiota?
Human follicular mites contain immune-reactive lipase which produce free fatty acids from sebum triglycerides
They could have a role in defence against S. aureus and Streptococcus pyogenes
in horses
D. caballi: longer; eyelids, muzzle
D. equi: shorter; body
Demodex in bovine
- D. bovis: pathogenic; eyelids, trunk
- D. ghanensisi: unknown significance; eyelids
- D. tauri: unknown significance
What does the scoring system in demodicosis evaluate
36 body locations
-mild (1-2), moderate (3-4), severe (5-6)
-erythema, papules, crusts, alopecia
