Hair-related diseases Notes

NOTES NOTES HAIR–RELATED DISEASES GENERALLY, WHAT ARE THEY? PATHOLOGY & CAUSES ▪ Conditions affecting either total number of hairs/thickness of hair on body ▪ Scalp most commonly affected SIGNS & SYMPTOMS ▪ See individual diseases DIAGNOSIS ▪ See individual diseases TREATMENT ▪ See individual diseases ALOPECIA AREATA osms.it/alopecia-areata PATHOLOGY & CAUSES ▪ Chronic localized hair loss, generally on scalp; autoimmune-related ▪ May occur at any age, but > 30 years old in most cases; lifetime prevalence 2% CAUSES ▪ Exact mechanism unclear; hypothesized ▫ T cells release cytokines, chemokines → normal hair cycle disrupted → hair loss ▪ Spontaneous regrowth of hair possible, often within one year RISK FACTORS ▪ Genetic ▫ Close family members, history of autoimmune conditions SIGNS & SYMPTOMS ▪ Usually smooth, circular patches of hair loss, but can be any shape ▪ Can be accompanied by nail changes ▫ Nail pitting, roughening/longitudinal fissuring of nail plate ▪ Associated with other autoimmune conditions ▫ Psoriasis, vitiligo, thyroid disease DIAGNOSIS LAB RESULTS ▪ Biopsy (unclear cases) ▫ Peribulbar lymphocytic inflammatory infiltrates characteristic ▫ Follicular edema, cellular necrosis, microvesiculation, pigment incontinence OSMOSIS.ORG 21

OTHER DIAGNOSTICS ▪ Based on timeline of events, physical examination (exclamation point hairs) ▫ Short, broken hairs around area of hair loss ▫ Narrower proximal than distal end ▫ Dermatoscope may make hairs easier to spot TREATMENT ▪ Treatment unreliable, temporary; no cure MEDICATIONS ▪ Intralesional steroid injections of triamcinolone acetonide ▪ Topical agents including 5% minoxidil solution/topical steroids Figure 4.1 The clinical appearance of the scalp in a case of alopecia areata. TELOGEN EFFLUVIUM osms.it/telogen-effluvium PATHOLOGY & CAUSES ▪ Periodic episodes of increased hair thinning/shedding due to altered follicle growth cycle ▫ Occurs during follicles’ telogen (resting) phase CAUSES ▪ May be related to ▫ Recent stressor (e.g. major illness/ surgery) ▫ Drugs/toxins ▫ Nutritional deficiencies SIGNS & SYMPTOMS ▪ Non-scarring, diffuse < 50% hair loss ▪ Nail changes ▫ Deep grooved lines running from side to side may be present 22 OSMOSIS.ORG DIAGNOSIS OTHER DIAGNOSTICS ▪ Determine timeline of stressors, recent events, drug/medication usage, course/ characteristics of hair loss ▪ Hair-pull test ▫ Grasp 50–60 hairs → tug lightly ▫ If > 6–10 hairs extracted, test = positive ▫ Telogen hairs confirmed by microscopic examination TREATMENT ▪ Sometimes self-correcting OTHER INTERVENTIONS ▪ Reduce stressors, improve diet, handle hair carefully

Chapter 4 Hair-related Diseases Figure 4.2 The clinical appearance of the nails in a case of telogen effluvium. OSMOSIS.ORG 23