Malassezia dermatitis is a common skin infection in dogs caused by the yeast Malassezia pachydermatis. It develops due to disorders that alter the skin environment or immune system. Clinically, it presents as erythematous, alopecic, and scaly skin with pruritus. Diagnosis is based on cytology and culture. Treatment involves systemic antifungals like ketoconazole for 3-4 weeks along with topical shampoos. Prognosis is good with prolonged therapy and follow up to prevent recurrence.

1.  Submitted To-
Dr.Anju Chahar
 Submitted By-
Kavita jaidiya
Malassezia dermatitis in dog

2. Introduction

3.  Malassezia yeasts are eukaryotic microorganisms placed in the
phylum Basidiomycota.
 Malassezia dermatitis develops secondarily to allergic,
endocrine, conformational, and keratinization disorders and
rarely develops due to immunocompromised status.
 Alteration of the cutaneous micro-climate or host defence
mechanisms allow the multiply and assume pahtogneic role.
(Foy DS and Trepanier LA., 2010).
 A common diagnosis in dogs, uncommon in cats, but possibly
under diagnosed in this species.
(Foy DS and Trepanier LA., 2010)
(Vaczi et al ., 2018 and Samaneh et al.,
2010).

4.  Malassezia pachydermatitis is a saprophytic and lipophilic
yeast, are commensal skin organisms of warm blooded
animals (Vaczi et al., 2018, Samaneh EIDI et al., 2010 and Nascente
et al., 2015).
 The only one non-lipid–dependent species M. pachydermatitis, is
commonly recovered from dogs and cats (Vaczi et al ., 2018).
 It is also commensal infection in human being, transmitted by
human health–care workers from their pet dogs to neonatal
patients (claudia cafarchia et al ., 2007, chang et al., 1998 and
chryssanthou et al., 2001).

5.  Multiplication of the yeast cells is promoted by higher pH
value in the specific cutaneous target sites (Mason et al.,
1996 and Matousek et al., 2003).
 It is found in the ear canals and skin of dogs, cats and
others species of domesticated and wild animals (Vaczi
et al ., 2018).

6. Pathogenesis

7.  Organism produce lipase that liberate acids and zymogen in
yeast cell which activates complement resulting into
inflammation (charach,1997).
 This opportunistic pathogen produces skin infections (Samaneh
et al ., 2010) depending on host factors and immune supressive
mechanisms (Akerstedt and Vollset ,1996) either independently or
as a sequel to other diseases like hypothyroidism
,demodecosis,hypoadrogenism,sertoli cell tumor, food
allergy,flea bite hypersentivity etc.
(Yathiraj S 2005)
 Metabolic products of the organism irritate the ear canal
epithelium which leads to hyperplasia with enlargement of the
ceruminous glands.

8.  EPIDEMIOLOGY

9.  There is no age or sex predilection except in one study that
demonstrated a predisposition of neutered male and female
dogs (Didier-Noël Carlotti 2005).
 Malassezia dermatits can affect any breed of dog, but the
following breeds are predisposed to this disease: poodles,
basset hounds, west highland white terriers, cocker spanials
and dachshunds (Didier-Noël Carlotti 2005).

10.  Malassezia dermatitis is often seasonal (from the end of spring
to the beginning of fall which is the time at which allergic
dermatitis are often diagnosed). It can persist during the winter
(Didier-Noël Carlotti 2005).
 There is no indication that Malassezia dermatitis is contagious.
(Didier-Noël Carlotti 2005)

11.  M.pachydermatitis has been considered to be Zoophilic and is
usually associated with otitis externa and various clinical
forms of dermatitis in domestic animals,particulary in dog
(Samaneh EIDI et al.2010).
 In contrast ,lipid dependent Malassezia species yeasts were
considered to be strickly anthropophilic (Samaneh EIDI et
al.2010).

12.  In healthy dogs, M.pachydermatitis could be isolated from the
ear canal or the skin (Petrove and Mihaylov, 2007).
 This organism is however very frequently detected in otitis or
dermatitis,independently or associated with other
microorganism as stayphylococcus spp,streptococcus
spp.,Escherichia coli and others . (Petrove and Mihaylov, 2007).

13. CLINICAL SIGNS

14.  Pruritus is always present and severe. Animals are presented
with a strong odour of rancid fat.
 At the beginning of the disease there are localized or diffused
erythema, erythematous papules and macules, and a
keratoseborrhoeic disorder with scaling, crusting and alopecia
and a greasy aspect of skin and hair.
 This is followed rapidly by secondary lesions such as
lichenification and hyper pigmentation.
(Didier-Noël Carlotti 2005) .

15.  Malassezia dermatitis can be localized, e.g., on the ventral
side of the body (neck, axillae, ventrum and inguinal area),
face (ear pinnae, lips, muzzle), peri-anal area and legs
(forearms, caudal thighs and feet). It can also be generalized.
It is not uncommon to observe concurrent otitis externa.
 Lymph node enlargement is sometimes seen but most often
there are no general signs.
(Didier-Noël Carlotti 2005)

16.  Corneal lesions can be either ulcerative or non-ulcerative in
nature. Fungal infections of cornea may be assosiated with
substantial ocular morbidity and result in vision or globe loss.(
Eric C et al., 2016 )

17.  The stromal ulcer associated with a dense leukocyte in filtrates
and raised yellow plaque.
 In vivo confocal microscopy of the cornea revealed the
corneal plaque composed of numberous leukocytes and
circular and oval structures that measured 2.5 -7.5 micrometer
in diameter.
 Clumps of these structure present on the exposed corneal
stroma and intermixed within epithelial cells on the periphery
of the corneal ulcer ,but did not appear to invade deeper into
the stromal the stromal tissue .
 Marked leukocyte and langerhans cell infiltrates present in the
epithelium surrounding the corneal plaques.
(Eric et al.,2016)

18. Generalized conditions
Malassezia
dermatitis in a
dog. A. The skin
is erythematous,
alopecic,
lichenified,
hyperpigmented,
and covered with
some scale.
Red-brown discoloration of claw

19. Erythema with
lichenification, and
greasy seborrhea due
to Malassezia (canine)
Erythema and greasy
seborrhea due to
atopic dermatitis-
related Malassezia
(canine
Lichenification and
greasy seborrhea
due to atopic
dermatitis-related
Malassezia (canine)
Malassezia
pododermatitis in a
canine patient
(canine)

20. a fluorescein stained anterior
stromal corneal ulcer associated
with a superficial yellow fungal
plaque

21.  Dogs with otits externa show
head shaking and ear
scraching .Exudate may
dry,reddish brown staining of
the claw in atoic
dogs,sometimes resulting in
residual pedal pruritus
(Griffin,1996).
 The dog may chew its feet or
srach in afrenzy manner at
the muzzle or the ears with its
front paws.
 The dogs shows sign of pain
when ears is touched.
 (Yathiraj S, 2005)
Otits
Malassezia otitis
externa secondary
to atopic dermatitis
(canine)

22.  Malassezia dermatitis diagnosed based on the case history
,clinical findings and surface cytological examination of
represenative samples collected from the affected areas.
 Dogs with history of receiving any systemic antibiotic/anti-
fungal medicine within the last 30 days were excluded from
this study. (Rucha borkar et al .,2014)
Diagnosis

23.  Several cytological techniques can be used
 Impression smear
 "Scotch test" using pieces of tape (clear cellophane) strip
 Scrape smear
 Swab smear
 Tape strip smears appeared to be the most reliable methods.
Swab smears should be reserved for cytological examination
of the external ear canal (Didier-Noël Carlotti 2005) .

24. Tape impression smear
 Impression smear from the lesion was stained with modified
wright s stains ,then stain with examined under oil immersion to
identify Malassezia spp.
 Microscopically ,Yeast cells (3-5 micrometer in diameter) with
unipolar budding ,imparting the typical peanut or boot shaped
appearance (Guilott and bond 1999)

25. Boot shaped
appearance of
malassezia
spp.

26.  The M.pachydermatitis isolates observe macroscopically as
cream to buff colored colonies that become darker with age
and had a dull,matte texture .
 The colonies convex with margins that entirely or slightly
lobed.
 Microflora significantly higher in samples collected from the
eyes of dogs with corneal ulcers (23% of sample culture
positive )than dogs with apparently normal eyes (Eric et al.,
2016).

27.  M.pachydermatis can be cultured from the conjunctival
microflora of a low percentage (3.8%) of dogs without overt
clinical ocular disease ,the frequency of M. pachydermatis
detection in the conjunctival microflora was significantly
higher in samples collected from the eyes of dogs with corneal
ulcers (23% of samples culture positive) than dogs with
apparently normal eyes (3% of samples culture positive)
(Eric et al., 2016).

28.  A corneal scraping was collected from the lession with a
kimura spatula for cytological evaluation,aerobic bacterial
culture, and fungal culture.
 The majority of the grossly visible yellow corneal plaque was
removed by gental manual scraping with kimura spatula .
 Neturophilic inflammation with numberous yeast cells
observed on cytology and M.pachydermatitis isolated during
fungal culture.
 Aerobic bacterial culture negative for growth. (Eric et al., 2016).

29.  Confirmation of malssezia spp.was done by culturing a
parallel sample from the skin lesion on sabouraud dextrose
agar or modified Dixon agar medium (32c ,3-5 days).
(Rucha borkar et al .,2014 and samaneh EIDI et al., 2010).

30.  Differential diagnosis includes many pruritic dermatoses with
erythema, hyperpigmentation and seborrhoea including
allergic skin diseases, bacterial folliculitis, demodicosis,
scabies, drug reaction, idiopathic acanthosis nigricans,
epitheliotropic lymphoma and all causes of seborrhoea with
cutaneous inflammation.
Differential diagnosis

31.  In fact clinical signs of Malassezia dermatitis are so variable
that it may mimic many dermatoses.
Furthermore, Malassezia dermatitis is often associated to or
even promoted by most of the dermatoses which are included
in its differential diagnosis.

32. The typical treatment duration is 3-4 weeks.
 Ketoconazole is the most commonly used drug.
 The dog suffering from malassezia disease were treated with
tab.pet oral k contaning 200mg ketoconazole at the rate of 5-
10 mg body weight a day.
Treatment
Systemic therapy

33.  Ketoconazole might have favourably modulated epidural cell
physiology ,cutaneous inflammation and hormonal activity in
skin and hair follicle (Ramprabhu et al., 2003) and anti-
inflammatory properties (lkhre, 1996)
 Ketoconazole may also act synergistically with the leukocytes
to disrupt the fungi (Uchida et al .,1992)

34.  As with all azole derivatives, ketoconazole acts in binding to
cytochrome P450, which inhibits synthesis of ergosterol, an
important component of the fungal cell membrane. This results
in alterations of cellular permeability and activity of various
membrane enzymes (Didier-Noël Carlotti 2005).

35.  Ketoconazole also has anti-inflammatory properties through
an action on leucotriene synthesis and it has an action on the
keratinization process through an action on alltrans retinoic
 acid(Didier-Noël Carlotti 2005)
MEDICATION DOSE
Ketoconazole 5-10 mg/kg PO q 24 hours
Itraconazole 5-10 mg/kg PO q 24 hours or 2
consecutive days per week
Fluconazole 10 mg/kg PO q 24 hours
Terbinafine 30 mg/kg PO q 24 hours or 2
consecutive days per week

36.  The azole class of antifungals may induce hepatotoxicity
and should be avoided or used with caution in patients
with hepatotoxicity. Many drug interactions with this
class are possible and concurrent medications should be
assessed. For prolonged use of the azole class antifungals,
a serum biochemistry profile is prudent to assess for
hepatotoxicity.
 Vasculitis and cutaneous ulcer may develop in 7.5% of
dogs treated with itraconazole at doses ≥10 mg/kg.
(Foy DS and Trepanier.,2017)

37.  It is recommended to give the drug with some food.
 Tolerance is usually good but periodic biochemistry panels are
necessary during long treatments.
 In effect ,an increase in serum transaminases may be followed
by signs of intolerance (anorexia,vomiting) due to hepatic
toixcity.
 Itraconazole could also be used (5 to 20 mg/kg every day or
other day).
(Didier-Noël Carlotti 2005)

38.  Malassezia pachydermatis has not shown any resistance to
antifungal agents commonly used against yeasts (azole
derivatives, nystatin, amphotericin B, 5- fluorocytosine).
Griseofulvin and allylamine derivatives are not effective in
treating Malassezia
 voriconazole effective in dog with resoltution of the corneal
infection without any clinical episodes of recurrence after
antifungal discontinuation.(Eric et al., 2016).
(Didier-Noël Carlotti 2005) .

40.  omega fatty acids contaning syrup like vitabest derm @10 ml
daily twice daily for 30 days .

41.  Topical therapy is an alternative to systemic treatment,
particularly for localized lesions (creams, gels, lotions or
sprays). For extensive lesions antifungal shampoos or lotions
are preferable, they can be used with systemic therapy
(Didier-Noël Carlotti 2005) .
 Shampoos containing miconazole (2%), chlorhexidine (at
least 3%), a combination of both (2% each) and ketoconazole
(2%) are the best (Didier-Noël Carlotti 2005).
B. Topical therapy

42.  ketochlor shampoo used for bathing , Topical treatments
should be administered 2 to 3 times a week during 2 weeks
then once a week.
 Better recovery obtained in similar case by using shampoo
contain selinium disulphides (Evans 1991).
Advised ; -Tab Petoral-K 200mg
sig 1.5 tab orally
-Syp. Nutricoat advance 200ml bottle
sig 1 tsp BID orally
-ketochlor shampoo 200ml bottle
sig for external use only
Advised to apply vinegar solution on
affected areas

43.  Therapeutic follow-up is very important.
 First of all, an improvement confirms the diagnosis. Pruritus
usually decreases within one week, whereas lesions will clearly
decrease after 2 weeks of treatment, particularly if both
systemic and topical therapies are used.
 The duration of treatment should be at least one month and can
be as long as 2 months to get a complete recovery. Usually
therapy is continued for 7 to 10 days beyond clinical cure
(Didier-Noël Carlotti,2005)
Therapeutic follow-up

44.  Otitis externa should be treated vigorously to limit the fungal
reservoir (nystatin, thiabendazole, clotrimazole, miconazole,
antiseptic cleansing agents, etc). In cases of concurrent
superficial pyoderma or bacterial overgrowth (BOG),
antibiotic therapy should be used (Didier-Noël Carlotti,2005).

45.  The therapy of malassezia-dermatits is usually based on
topical or systemic administration of antifunagals (mainly
those of azoles ) and direct application of antifugal
 Antiseptic substances.An alternative and attractive possibility
of supportive therapy is the use of essential oils.
()
(Vaczi et al ., 2018)

46.  Essential oil of the following medicinal plants are effective-
bergamot,cedar,chamomile,cinnamon,clove,grapefruit,juniper,l
avander,oregano,pine,sage,satureja-winter savory, tea tree and
common yarrow.
 The essential oil act as antibacterial agent and also act on
various microscopic fungai.
 Essential oil of clove ,cinnamon and oregano in concentration
30% show excellent activity against M.pachydermatis.
 The formation of inhibition zones of
cedar,chamole,sage,grapefruit and te-tree oil indicated their
partial efficacy.

47.  BATH WITH ANTIFUNGAL
SHAMPOO
 CLEANING OF KENNEL
 REGULAR CHECKUP
PREVENTION AND CONTROL