Acne Flashcards
Tell me about P acnes
- Gram positive, anaerobic, microaerophilic rod in the sebaceous follicle
- Produces porphyrins: fluoresces with Woods lamp
- Density does not correlate with clinical severity
- Certain ribotypes (4 and 5)are more frequently found in acne patients
Four contributors of acne pathogenesis
- Follicular hyperkeratosis (microcomedone)
- Hormones
- Inflammation
- P acnes
What causes the black colour in open comedones
Melanin and lipid oxidation may be responsible for black colour
Extra-cutaneous features of acne fulminans
- Bones: osteolytic bone lesions: clavicle, sternum, then can also be ankles, humerus, iliosacral joints
- Systemic: fever, arthralgias, myalgias, hepatosplenomegaly, severe malaise
- Erythema nodosum
- SAPHO syndrome can accompany
- Associated with congenital adrenal hyperplasia and anabolic steroid use (including therapeutic testosterone)
What is PAPA syndrome and its mutation
- Sterile pyogenic arthritis, PG, acne conglobata
- Mutations in PSTPIP1 - proline - serine - threonine - phosphatase interacting protein 1
Morbihan disease
- Distortion of the midline face and cheeks due to soft tissue swelling
- Woody induration and erythema
- ?cause: impaired lymphatic drainage and fibrosis in setting of chronic inflammation, some genetic risk
- Can be seen with rosacea
- Fluctuations in severity are common
- Does not resolve spontaneously
- Rx:
- Isotretinoin 0.2-1 mg/kg/day for 4-6 months, may need longer
- Combination with this and ketotifen (H1 antihistamine and mast cell stabiliser) or prednisone may be more beneficial
What weeks for neonatal acne
Appear at ~ 2 weeks of age, and resolve by first 3 months
What months for infantile acne
2-12 months of age
Hyperandrogenism signs
- Hirsutism
- Coarsening of voice
- Muscular habitus
- Androgenetic alopecia
- Clitoromegaly with variable posterior labial fusion
- Increased libido
HAIR-AN syndrome
Insulin resistance, acanthosis nigricans and hyperandrogenism: at increased risk of CVS disease and DM
Acne associated with genetic syndromes
- Apert syndrome:
- Autosomal dominant
- Disfiguring synostoses of the bones, - hands and feet, vertebral bodies, cranium
- Increased incidence of severe, early-onset acne that is nodulocystic and more widespread than classic acne - extensors of arms, buttocks and thighs
- Acne typically resistant to treatment, roaccutane may be beneficial
- Other cutaneous: seborrhoea, nail anomalies (single nail for second throug fourth digits), diffuse pigmentary dilution of hair and skin
- Mutation ins FGFR2 - encodes fibroblast growth factor receptor 2 –> effects follicular keratinocyte proliferation, sebaceous lipogenesis, inflammatory cytokine production
- Borrone dermato-cardio-skeletal syndrome:
- Autosomal recessive
- SH3PXD2B mutation
- Dysmorphic facies, thick skin, acne conglobata, vertebral abnormalitis, mitral valve prolapse
- PAPA
- PAPASH
- PASH
Drug induced acne
- monomorphous eruption of inflammatory papules and pustules
- Medications - did you MISPLACE your meds Bae?
MEK inhibitors (trametinib) Iodides, isoniazid Steroids Phenytoin, progestins Lithium Anabolic steroids - danazol, testosterone Corticotropin, cyclosporin EGFR inhibitors
Bromide, B6, B12
Azathioprine
Chloracne
- several weeks after exposure to halogenated aromatic hydrocarbons
- Can be percutaneous, inhalation of ingestion
- Found in electrical conductors, insulators, insecticides, fungicides, herbicides, wood preservatives
- Comedo like lesions and yellowish cysts with minimal inflammation - malar and retroaurciular areas of head and neck, and can be on axillae and scrotum
- Can persist for several years following exposure
- Additional: grayish discolouration, hypertrichosis
- Rx: remove, topical or oral retinoids
Radiation acne
- comedone like papules at sites of previous exposure to therapeutic ionizing radiation
- appear as acute phase of radiation dermatitis starts to resolve
- The rays induce epithelial metaplasia within the follicle, creating adherent hyperkeratotic plugs that are resistant to expression
Idiopathic facial aseptic granuloma
- thought to be form of rosacea in children
- young - 2-4 years of age roughly
- Dermal lymphohistiocytic infiltrate with foreign body type giant cells
- > 40% have at least 2 other signs of rosacea: recurrent chalazions, facial flushing, telangiectasias, papulopustules