Title: Sebaceous adenitis

{{short description|Skin disease}}
[[File:Sebadenitis.jpg|thumb|right|Sebaceous adenitis and hair loss in a dog]]

'''Sebaceous adenitis''' is an uncommon skin disease found in some breeds of dog, and more rarely in cats, rabbits and horses.&lt;ref name=Craig&gt;{{cite journal |pages=62–8 |doi=10.1111/j.2044-3862.2006.tb00066.x |title=Clinical refresher: Canine sebaceous adenitis |year=2006 |last1=Craig |first1=Mark |journal=Companion Animal |volume=11 |issue=5}}&lt;/ref&gt; characterised by an inflammatory response against the dog's [[sebaceous glands]] (glands found in the [[hair follicles]] in the skin [[dermis]]), which can lead to the destruction of the gland. It was first described in veterinary literature in the 1980s.&lt;ref name=Spaterna&gt;{{cite journal |pages=441–443 |doi=10.1023/B:VERC.0000014199.39879.bb |title=Sebaceous Adenitis in the Dog: Three Cases |year=2003 |last1=Spaterna |first1=A. |last2=Antognoni |first2=M.T. |last3=Cappuccini |first3=S. |last4=Tesei |first4=B. |journal=Veterinary Research Communications |volume=27 |pmid=14535449|s2cid=30352408 }}&lt;/ref&gt;

==Signs==
There are two expressions of this condition, one for long or double coated breeds and one for short coated breeds, both with differing presentations.&lt;ref name=&quot;Linek&quot;/&gt;

* For long- or double-coated breeds such as Poodles, Akitas and Samoyeds, the condition often presents itself with silvery dandruff which adheres to the coat, hair loss (not to be confused with [[moulting]] or &quot;blowing coat&quot;), a dull and brittle coat, and later on skin lesions along the back and ears&lt;ref name=&quot;Linek&quot;/&gt; as well as thickened skin and a musty or rancid odour.&lt;ref name=Upei&gt;{{cite web|title=Sebaceous Adenitis |url=http://www.upei.ca/~cidd/Diseases/dermatology/sebaceous%20adenitis.htm |publisher=Canine Inherited Disorders Database |access-date=10 April 2011 |year=1998  |archive-url=https://web.archive.org/web/20110605062817/http://www.upei.ca/~cidd/Diseases/dermatology/sebaceous%20adenitis.htm |archive-date=June 5, 2011 }}&lt;/ref&gt; 
* For short-coated breeds such as Vizslas, the condition causes facial swellings, nodular skin lesions, fine dandruff which does not adhere to the coat, and a general &quot;moth-eaten&quot; appearance to the coat.&lt;ref name=&quot;Linek&quot;/&gt;

==Cause==
[[File:Skin.png|thumb|Anatomy of human skin, which shows the location of human and canine sebaceous glands]]

The signs of sebaceous adenitis are caused by an [[Inflammation#Disorders|inflammatory disease]] process which affects the [[sebaceous gland]]s of the skin.&lt;ref name=&quot;Rosser 2014&quot;&gt;{{cite book|last1=Rosser|first1=EJ Jr|editor1-last=Bonagura|editor1-first=JD|editor2-last=Twedt|editor2-first=DC|title=Kirk's current veterinary therapy|date=2014|publisher=Elsevier/Saunders|location=St. Louis, Mo.|isbn=9780323227629|edition=15th|chapter=Therapy for sebaceous adenitis}}&lt;/ref&gt; The cause of the inflammatory disease is unknown.&lt;ref name=&quot;Paterson 2009&quot;/&gt; Different breeds of dogs may have different underlying causes of the disease.&lt;ref name=&quot;Paterson 2009&quot;&gt;{{cite book|last1=Paterson|first1=Sue|title=Manual of Skin Diseases of the Dog and Cat.|date=2009|publisher=John Wiley &amp; Sons|location=Chichester|isbn=9781444309324|pages=277–291|edition=2nd|chapter=Chapter 17: Keratinisation defects}}&lt;/ref&gt;

Research is currently underway to find if there is a genetic predisposition for sebaceous adenitis; the exact mode of inheritance remains unknown.&lt;ref name=Koch&gt;{{cite web |last=Koch |first=Sandra N. |title=01346-A: Genetic Basis of Sebaceous Adenitis in Dogs |url=http://www.akcchf.org/research/funded-research/1346.html |publisher=University of Minnesota |access-date=7 April 2011 |date=June 1, 2009 – November 30, 2010 |archive-url=https://web.archive.org/web/20111002223855/http://www.akcchf.org/research/funded-research/1346.html |archive-date=2011-10-02  }}&lt;/ref&gt;

In [[Standard Poodle]]s, sebaceous adenitis is most likely an [[autosomal recessive]] inherited disease, with [[Expressivity (genetics)#Variable expressivity|variable expression]].&lt;ref name=&quot;Rosser 2014&quot; /&gt;

==Diagnosis==
In general, sebaceous adenitis is underdiagnosed in dogs.&lt;ref name=&quot;Craig&quot;/&gt; Diagnosis confirmation requires multiple punch biopsies analysed by a dermopathologist who will comment on the condition of the sebaceous glands, revealing granulomatous or pyogranulomatous inflammation surrounding the sebaceous glands or even complete destruction of sebaceous glands.&lt;ref name=&quot;Hall&quot;/&gt;

Other conditions with similar presentations include: [[Folliculitis#Bacterial|bacterial folliculitis]] and [[demodicosis]], [[dermatophytosis]], [[endocrinopathy]], [[pemphigus foliaceus]], [[Zinc deficiency#Dietary deficiency|zinc responsive dermatosis]], vitamin A-responsive dermatosis, [[ichthyosis]], and nutritional deficiencies.&lt;ref name=&quot;Angus&quot;/&gt; As well as, superficial [[pyoderma]], primary idiopathic [[Seborrhoeic dermatitis|seborrhea]] and other endocrine diseases.&lt;ref name=&quot;Hall&quot;/&gt;

==Treatment==
There is no cure for this condition.&lt;ref&gt;{{Cite web|url=https://www.ofa.org/diseases/other-diseases/sebaceous-adenitis|title=Sebaceous Adenitis|website=Orthopedic Foundation for Animals|language=en-US|access-date=2019-09-27}}&lt;/ref&gt; Treatment is generally lifelong&lt;ref name=&quot;Linek&quot;/&gt; and takes the form of bathing and soaking in mineral oils and washing with antibiotic shampoos to try to alleviate symptoms and slow the condition's progression.&lt;ref name=petmd&gt;{{cite web|title=Inflammatory Skin Disease in Dogs|url=http://www.petmd.com/dog/conditions/skin/c_dg_sebaceous_adenitis?page=2|access-date=10 April 2011}}&lt;/ref&gt; Antiseptic and antibiotic shampoos (chlorhexidine or benzoyl peroxide) are used to manage further secondary bacterial infection.&lt;ref name=&quot;Angus&quot;/&gt; For some breeds, [[cyclosporine]] or [[corticosteroids]] and [[immunosuppressant]] drugs may be effective,&lt;ref name=&quot;Linek&quot;/&gt; and it is postulated, through some studies, that large doses of vitamin A given orally may result in some improvement.&lt;ref name=&quot;Linek&quot;/&gt;

It has been suggested that the more aggressively one applies the [[topical]] methods of treatment, the less aggressively one needs to employ the immunosuppressant therapy. The suggestion is that this phenomenon may be due to a [[wiktionary:cyclic|cyclic]] feedback whereby secondary infection, when not aggressively treated with topical therapy, increases and contributes to further sebaceous gland inflammation.&lt;ref name=&quot;Angus&quot;/&gt;

=== Topical therapy ===
This forms a major and critical part in the disease treatment and the shampoo treatment can need to be applied as often as 3 to 4 times per week.&lt;ref name=&quot;Angus&quot;/&gt; An antiseborrheic shampoo removes the scale blocking the [[Hair follicle|follicles]]. The mineral oil soak, whereby the oil remains on the affected animal for at least 2 hours, is needed to replace epidermal lipids as well as to restore normal epidermal barrier function. The oil is then removed through the process of many baths. This oil treatment needs to be repeated at least once a week for 4 to 7 weeks until new hair growth is observed.&lt;ref name=&quot;Angus&quot;/&gt; Once new hair growth is observed, topical treatment can be decreased to every 2 to 4 weeks.

=== Immunosuppressant therapy ===
Immunosuppressant and anti-inflammatory therapy serves to stop on-going destruction of the sebaceous glands. Like other inflammatory diseases, most animals receive an initial course to stop the inflammation and treatment is tapered off to the lowest dose that keeps the disease in remission.&lt;ref name=&quot;Angus&quot;/&gt; Oral [[cyclosporine]] may be used.&lt;ref name=&quot;Angus&quot;/&gt; Corticosteroids (e.g. prednisone) are used only if [[Itch|pruritus]] is a major clinical feature.&lt;ref name=&quot;Angus&quot;/&gt;

=== Dietary supplementation ===
Commonly used dietary supplements include:

* [[Omega-6 fatty acid]]s (e.g., safflower or sunflower oil)
* [[Omega-3 fatty acid]]s (e.g., fish oils)
* [[Vitamin A]].&lt;ref name=&quot;Angus&quot;/&gt;

==Epidemiology==
While the condition has been seen in over 60 breeds of dog (including cross breeds),&lt;ref name=&quot;Angus&quot;/&gt;&lt;ref name=&quot;VetStream Idio-Granu&quot;&gt;{{cite web|title=Skin: idiopathic/granulomatous sebaceous adenitis|url=http://www.vetstream.com/canis/Content/Disease/dis02634.asp|publisher=VetStream|access-date=19 July 2011|author=Mr Charlie Walker BVetMed CertVD MRCVS|location=Cambridge CB21 4EN, UK|year=2010|archive-date=22 March 2012|archive-url=https://web.archive.org/web/20120322204239/http://www.vetstream.com/canis/Content/Disease/dis02634.asp}}&lt;/ref&gt; certain breeds have been found to be more susceptible than others to sebaceous adenitis:

* [[American Akita]] and [[Akita Inu]]&lt;ref name=Pfeiffer&gt;{{cite web |last=Pfeiffer |first=Ina |title=577-AT: Sebaceous Adenitis in the Akita |url=http://www.akcchf.org/research/funded-research/0816.html |access-date=7 April 2011 |date=April 1 – June 30, 2006 |archive-url=https://web.archive.org/web/20111002223934/http://www.akcchf.org/research/funded-research/0816.html |archive-date=2011-10-02  }}&lt;/ref&gt;&lt;ref name=&quot;Hall&quot;/&gt;
* [[Standard Poodle]]&lt;ref name=&quot;Pfeiffer&quot;/&gt;&lt;ref name=&quot;Hall&quot;/&gt;
* [[Vizsla]]&lt;ref name=&quot;Pfeiffer&quot;/&gt;&lt;ref name=&quot;Hall&quot;/&gt;
*[[English Springer Spaniel]]&lt;ref name=Hernblad&gt;{{cite journal |pmid=18501018 |year=2008 |last1=Hernblad Tevell |first1=E |last2=Bergvall |first2=K |last3=Egenvall |first3=A |title=Sebaceous adenitis in Swedish dogs, a retrospective study of 104 cases |volume=50 |page=11 |doi=10.1186/1751-0147-50-11 |pmc=2412885 |journal=Acta Veterinaria Scandinavica|issue=1 |doi-access=free }}&lt;/ref&gt;
* [[Chow Chow]]&lt;ref name=&quot;Gross&quot;/&gt;&lt;ref name=Angus&gt;{{cite web|last=Angus, DVM, DACVD|first=John C.|title=How I Treat Sebaceous Adenitis|url=http://www.docstoc.com/docs/75732894/Pe-How-treat-Sebaceous-Adenitis|page=1|publisher=Omnibooks Online|access-date=2 June 2011|location=Animal Dermatology Clinic, Pasadena, CA, USA|year=2009}}&lt;/ref&gt;
* [[Samoyed dog|Samoyed]]&lt;ref name=&quot;Craig&quot;/&gt;&lt;ref name=&quot;Hall&quot;/&gt;
* [[Weimaraner]]&lt;ref name=Hall&gt;{{cite web|last=Hall|first=Jan A.|title=Congenital and Hereditary Defects in Skin Disease|url=http://scholar.googleusercontent.com/scholar?q=cache:Rf0zbWa1ksAJ:scholar.google.com/+Congenital+and+Hereditary+Defects+in+Skin+Disease&amp;hl=en&amp;as_sdt=0,5&amp;as_vis=1|publisher=Omnibooks Online|access-date=2 June 2011|location=Ontario Veterinary College, University of Guelph, Canada|year=2005}}{{Dead link|date=August 2018 |bot=InternetArchiveBot |fix-attempted=yes }}&lt;/ref&gt;
* [[Havanese dog|Havanese]]&lt;ref name=Frazer&gt;{{cite journal|last=Frazer|first=Megan|author2=Anthea E. Schick |author3=Thomas P. Lewis |author4=Edward Jazic |title=Sebaceous adenitis in Havanese dogs: a retrospective study of the clinical presentation and incidence|journal=Veterinary Dermatology|date=June 2011|volume=22|issue=3|pages=267–274|doi=10.1111/j.1365-3164.2010.00942.x|pmid=21210878}}&lt;/ref&gt;
Breeds also mentioned in scientific literature as having some susceptibility include:
* [[German Shepherd]]&lt;ref name=Gross&gt;{{cite book |last=Gross |first=Thelma Lee |title=Skin diseases of the dog and cat: clinical and histopathologic diagnosis |year=2005 |publisher=Wiley-Blackwell |pages=186–8|isbn=978-0-632-06452-6 |edition=second |author2=Peter J. Ihrke |author3=Emily J. Walder |author4=Verena K. Affolter }}&lt;/ref&gt;
* [[Dachshund]]&lt;ref name=&quot;Craig&quot;/&gt;
* [[Old English Sheepdog]]&lt;ref name=&quot;Gross&quot;/&gt;
* [[Lhasa Apso]]&lt;ref name=&quot;Gross&quot;/&gt;
* [[Boxer (dog)|Boxer]]&lt;ref name=&quot;Gross&quot;/&gt;
* [[Collie]]&lt;ref name=&quot;Gross&quot;/&gt;
* [[Toy Poodle]]&lt;ref name=&quot;Gross&quot;/&gt;
* [[Mixed-breed dog|Mixed-breeds]]&lt;ref name=Linek&gt;{{cite journal|last=Linek|first=Monika|title=Sebaceous adenitis in the dog|journal=Veterinary Focus|year=2008|volume=18|issue=1|pages=12–16|url=http://www.edliny.com/Encyclopedy/Veterinary%20Focus/181/2.pdf|access-date=10 April 2011|archive-url=https://web.archive.org/web/20120322133027/http://www.edliny.com/Encyclopedy/Veterinary%20Focus/181/2.pdf|archive-date=22 March 2012|doi=10.1055/s-0034-1381781}}&lt;/ref&gt;

Sebaceous adenitis has no sex-predisposition.&lt;ref name=&quot;Craig&quot; /&gt; Sebaceous adenitis also occurs in cats,&lt;ref name=&quot;Hall&quot;/&gt; rabbits,&lt;ref name=&quot;Linek&quot;/&gt;&lt;ref name=VetstreamSA&gt;{{cite web|title=Sebaceous adenitis|url=http://www.vetstream.com/lapis/content/Freeform/fre00082.asp|publisher=VetStream|access-date=19 July 2011|author=Anna Meredith|author2=Stephen White|location=Cambridge CB21 4EN, UK|year=2010|archive-date=11 October 2013|archive-url=https://web.archive.org/web/20131011015808/http://vetstream.com/lapis/Content/Freeform/fre00082.asp}}&lt;/ref&gt; and horses.&lt;ref name=Osborne&gt;{{cite journal |last=Osborne |first=Christina |pmid=16808233 |year=2006 |title=Sebaceous adenitis in a 7-year-old Arabian gelding |volume=47 |issue=6 |pages=583–6 |pmc=1461412 |journal=The Canadian Veterinary Journal}}&lt;/ref&gt;

==Etymology==
[[Adenitis]] is a general term referring to inflammation of a gland. [[Sebaceous]] refers to the oil gland, which is the gland affected by this disease.

== See also ==
* {{portal-inline|Dogs}}

==References==
{{reflist}}

==Further reading==
* {{cite journal |pages=243–53 |doi=10.1046/j.0959-4493.2001.00251.x |title=Sebaceous adenitis in the Akita: clinical observations, histopathology and heredity |year=2001 |last1=Reichler |first1=Iris M. |last2=Hauser |first2=Beat |last3=Schiller |first3=Irene |last4=Dunstan |first4=Robert W. |last5=Credille |first5=Kelly M. |last6=Binder |first6=Heinrich |last7=Glaus |first7=Toni |last8=Arnold |first8=Susi |journal=Veterinary Dermatology |volume=12 |issue=5 |pmid=11906649}}

[[Category:Dog diseases]]
[[Category:Autoimmune diseases]]