7. FUNCTIONS OF SEBUM
• Reduces water loss from the skin surface
• Protects the skin from infection by bacteria and fungi
• Contributes to body odour
• Colonised by the bacteria Proprionibacterium acnes- role in immune
system regulation
• Prevents upper layers from oxidation
• Innate immunity –antimicrobial peptides and TLR expression
15. ANDROGENS
• Majority –gonads and adrenals,Local-sebocyte(DHEAS)
• Androgen receptors-Basal layer of sebaceous gland,Outer root sheath
• Increased activity-increased gland size
• DHT more potent
• Androgens MOA:
Increasing the proliferation of sebocytes
Increasing lipid production through SREBP
• Cytp450 side-chain cleavage system (P450 Scc)-Paracrine effects
16.
17.
18. ESTROGENS
• Produced from testosterone by aromatase
• Estradiol converted to Estrone by 17 beta HSD
• Mechanism of action:
Negative feedback-decreases testosterone levels
Increases SHBG levels
Direct opposition of androgen within the sebaceous gland
Gene regulation of sebaceous gland growth and lipid production
19. GROWTH HORMONE
• Stimulates production of insulin-like growth factors (IGF)
• GH receptor -hair follicles and the acini of sebaceous gland
• Natural course of acne from its onset to puberty –GH levels
• Acromegaly-increased sebum production
22. CRH AND ACNE
CRH
POMC
MSH AND ACTH
MC1R MC5R
IL-8 PRODUCTION
sebocyte differentiation
and lipogenesis
23. CRH AND ACNE
• Released by dermal nerves and sebocytes
• MOA:
a) Inhibits sebaceous proliferation
b) Promotes sebaceous differentiation
c) Induces sebaceous gland lipogenesis
d) Enhances androgen bioavailability
e) Stimulates the conversion of DHEA to testosterone.
27. GUT DYSBIOSIS
• Intestine is colonized by a complex microbial ecosystem
• 1955 - Loveman et al-Bacteroides species were more commonly
isolated from the acne patients
• 54% of acne patients have differences in their intestinal flora
• Had improvement with probiotic use
• Lower counts of Bifidobacterium in fecal specimens from patients
with atopic dermatitis-Gut skin connection
28.
29. PROBIOTICS AND ACNE
• Probiotics are live microorganisms that can alter gut homeostasis and
immunity
• 1930- used orally-administered Lactobacillus acidophilus cultures as a
probiotic to treat acne
• First case reports-1961-L. acidophilus and Lactobacillus bulgaricus
• Effectiveness of probiotics as adjuvants to standard acne treatment
with antibiotics
31. DIET AND ACNE
• 2007- Smith et al.compared the effect of a low-glycemic load diet on
acne severity
• Patients both lost weight and showed improvement of acne
• Free androgen and fasting insulin levels were significantly lower
32. Smith RN, Mann NJ, Braue A, Mäkeläinen H, Varigos GA. The effect of a high-protein, low glycemic–load diet versus a conventional, high glycemic–load
diet on biochemical parameters associated with acne vulgaris: A randomized, investigator-masked, controlled trial. Journal of the American Academy of
Dermatology. 2007 Aug 1;57(2):247-56.
50. SAHA SYNDROME
• Association of seborrhoea and acne with hirsutism and ⁄ or
androgenetic alopecia
• Classified into
1) Idiopathic,
2) Ovarian,
3) Adrenal
4) Hyperprolactinaemic type
• Can be associated with polycystic ovaries, cystic mastitis, obesity,
insulin resistance and infertility
53. SAPHO SYNDROME
• SAPHO -synovitis, acne, pustulosis, hyperostosis and osteitis
• Acne ⁄ hidradenitis suppurativa ⁄ dissecting cellulitis of the scalp,
psoriasis⁄ pustular psoriasis⁄ palmoplantar pustulosis, Sweet’s
syndrome, Sneddon-Wilkinson disease and pyoderma gangrenosum
• Bones in anterior chest wall , sacroiliac joints and extremities
• Association with inflammatory bowel diseases such as Crohn’s disease
and ulcerative colitis
• Recalcitrant lesions –Myelodysplastic syndrome
54.
55. ETIOPATHOGENESIS
• SAPHO syndrome may be triggered by an infectious state potentially
caused by P. acne
• P. acnes induced production of IL-8 and TNF-a
56. Song X, Sun W, Meng Z, et al. Diagnosis and treatment of SAPHO syndrome: A case report. Exp Ther Med. 2014;8(2):419-422.
57. Song X, Sun W, Meng Z, et al. Diagnosis and treatment of SAPHO syndrome: A case report. Exp Ther Med. 2014;8(2):419-422.
58. Song X, Sun W, Meng Z, et al. Diagnosis and treatment of SAPHO syndrome: A case report. Exp Ther Med. 2014;8(2):419-422.
59. Song X, Sun W, Meng Z, et al. Diagnosis and treatment of SAPHO syndrome: A case report. Exp Ther Med. 2014;8(2):419-422.
60.
61. PAPA SYNDROME
• Triad of pyogenic sterile arthritis, pyoderma gangrenosum (PG) and
acne conglobata
• Causative gene-CD2-binding protein 1 (CD2BP1/ PSTPIP1)
• Inheritance- autosomal dominant
66. DRUG MECHANISM CLINICAL FEATURES
Corticosteroids steroid-induced TLR2 together with P.
acnes play an important
role
• monomorphous papulo-pustular
eruption
• Comedones may be present
• located predominantly on the trunk
and extremities
Anabolic steroids • Increase cutaneous population of
Propionibacterium acne
• Increase cholesterol and free fatty
acids
• Aggravation of preexisting
acne vulgaris
• male pattern hair loss
• Hirsutism
• Acne fulminans and acne conglobata
Lithium • Neutrophilic chemotaxis and their
degranulation
• Follicular plugging due to direct
influence of lithium on the follicular
keratinocytes
• consist of monomorphic,
papulopustular eruption of the
face, trunk, and extremities
• postinflammatory scarring is
present
Isoniazid Induces acne and
pellagra due to slow inactivators of the
drug
• predominantly of inflammatory
follicular papules
67. CLINICAL SIGNS ACNE VULGARIS DRUG INDUCED ACNE
HISTORY no history for drug
intake
history of present illness
and/or drug intake
ONSET onset during teenaged
years, or late onset
beginning after the age
of 25 years (adult acne)
Sudden onset
(occurrence often away
from acne age)
LOCALISATION appearance on the face,
chest, and back
appearance on the face
and neck, unusual
location of the lesions
beyond the seborrheic
areas
TYPES OF LESIONS polymorphous
eruption: comedones,
papules, pustules,
nodules, and cysts
monomorphous
eruption: inflammatory
papules or papulopustules;
no comedones
or if present, they are
secondary lesions
PROGNOSIS Acne can almost always
be controlled with
medication; however,
results may not be seen
Lesions disappear with
the discontinuation of
the inducing drug
71. EGFR INHIBITOR
Holcmann M, Sibilia M. Mechanisms underlying skin disorders induced by EGFR inhibitors. Mol Cell Oncol. 2015;2(4):e1004969. Published 2015 Jun 1.
doi:10.1080/23723556.2015.1004969
74. CHLORACNE
• Caused by certain toxic halogenated aromatic hydrocarbon chemicals.
• MADISH—Metabolising Acquired Dioxin Induced Skin Hamartomas
• Present in Fungicides,Insecticides,Herbicides,wood preservatives
• Dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin) intoxication
75.
76.
77. CHLORACNE
• C/F-non-inflammatory black and white comedones and straw-colored
cysts, papules and nodules.
• Other findings-brownish hyperpigmentation of the nails,
hypertrichosis, and hyperpigmentation.
• HPE-Dilated infundibulum filled with keratinized cells and comedones
consisting of sebum, sebaceous glands have disappeared
• Chloracne is often resistant to therapy.
82. COSMETIC USE
• Due to chronic use of cosmetics containing potentially comedogenic
substances
• Chemicals -lanolin, petrolatum, certain vegetable oils, butylstearate,
lauryl alcohol and oleic acid
• Skin bleaching agents-exacerbates acne
• Pomade acne-greasy preparations used to defrizz curly hair
• Detergent acne-patients who wash many times-Trauma ,alkalinity
83. UV RADIATION AND ACNE
• UVR may promote acne on sun‐exposed skin in susceptible
individuals
• Hot and humid climate –Negates effects of sunlight
• Mallorcan acne/Acne aestivalis:
a) Small follicular papules appear, especially on the upper trunk
b) During or after a holiday in a hot humid environment
• PUVA and acne-Squalene monohydroperoxide
84. REFERENCES
• Harper JC. An update on the pathogenesis and management of acne
vulgaris. Journal of the American Academy of Dermatology. 2004 Jul
1;51(1):36-8.
• Das S, Reynolds RV. Recent advances in acne pathogenesis:
implications for therapy. American journal of clinical dermatology.
2014 Dec 1;15(6):479-88.
• Dréno B. What is new in the pathophysiology of acne, an overview.
Journal of the European Academy of Dermatology and Venereology.
2017 Sep;31:8-12.
85. REFERENCES
• Melnik BC. Linking diet to acne metabolomics, inflammation, and
comedogenesis: an update. Clinical, cosmetic and investigational
dermatology. 2015;8:371.
• Kazandjieva J, Tsankov N. Drug-induced acne. Clinics in dermatology.
2017 Mar 1;35(2):156-62.
• Chen, W., et al. "Acne‐associated syndromes: models for better
understanding of acne pathogenesis." Journal of the European
Academy of Dermatology and Venereology 25.6 (2011): 637-646.
86. REFERENCES
• Clark A, Haas K, Sivamani R. Edible plants and their influence on the
gut microbiome and acne. International journal of molecular sciences.
2017 May;18(5):1070.
• Lichtenberger, R., et al. "Genetic architecture of acne
vulgaris." Journal of the European Academy of Dermatology and
Venereology 31.12 (2017): 1978-1990.
• Melnik, Bodo, and Gerd Schmitz. "FGFR2 signaling and the
pathogenesis of acne." JDDG: Journal der Deutschen
Dermatologischen Gesellschaft 6.9 (2008): 721-728.
87. REFERENCES
• Balachandrudu, B., V. Niveditadevi, and T. Prameela Rani. "Hormonal
pathogenesis of acne–simplified." Int J Sci Stu 3 (2015): 183-185.
• Beylot C, Auffret N, Poli F, Claudel JP, Leccia MT, Del Giudice P, Dreno
B. Propionibacterium acnes: an update on its role in the pathogenesis
of acne. Journal of the European Academy of Dermatology and
Venereology. 2014 Mar;28(3):271-8.
• Griffiths, Christopher, et al., eds. Rook's textbook of dermatology.
John Wiley & Sons, 2016.
• Fitzpatrick’s dermatology in general medicine. 8th ed. New York:
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