Updated: 1/23/2017

Alopecia Areata

Review Topic
  • A 35-year old woman with a past medical history of atopic dermatitis comes to the dermatologist for multiple, round patches of balding on her scalp. She has had more and more of these bald spots for about 2 months. She cannot recall any instigating events and denies pulling out her hair intentionally. Physical exam reveals no inflammation or erythema in the affected areas. A punch biopsy reveals lymphocytic infiltration. She has a family history of rheumatoid arthritis and Grave’s disease. 
  • Chronic, autoimmune non-scarring hair loss disorder
    • as opposed to scarring cicatricial alopecic disorders such as discoid lupus or lichen planopilaris that lead to destruction of hair follicle
  • Epidemiology:
    • rare (1.7% lifetime risk of developing disease)
    • affects males and females equally
    • affects children and adults equally
  • Associated conditions:
    • other autoimmune diseases, especially thyroid and atopic disorders 
  • Symptoms:
    • smooth, discrete, circular patches of hair loss that are typically without pain or itchiness
    • can spontaneously regrow hair or spontaneously progress to alopecia totalis/universalis
    • no erythema, inflammation, or scarring
    • nail abnormalities are common, including pitting of nail plate
  • Clinical evaluation of hair loss sites
    • “exclamation point hairs” at margins of patches
      • short, broken hairs that narrow at the base
      • extracted easily
      • low sensitivity
  • Punch biopsy
    • peribulbar lymphocytic inflammatory infiltrates surrounding follicles
  • Laboratory studies normal
Differential Diagnosis
  • Tinea capitis
  • Trichotillomania (nervous hair pulling)
  • Androgenetic alopecia
  • Cicatricial alopecia
  • Telogen effluvium
  • Traction alopecia
    • secondary to hair tension that is prolonged or repetitive
  • Watchful waiting for mild cases, as hair may regrow spontaneously
  • Limited therapies available; all with limited efficacy
    • intralesional corticosteroids (triamcinolone)
    • topical steroids
    • pulsed prednisone
    • topical immunotherapy
  • Currently under investigation: targeted immunotherapies
    • janus kinase inhibitors tofacitinib, ruxolitinib 
Prognosis, Prevention, and Complications
  • Variable, unpredictable pattern of regrowth, patchy hair loss, and progression to alopecia totalis or universalis 

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Questions (2)
Lab Values
Blood, Plasma, Serum Reference Range
ALT 8-20 U/L
Amylase, serum 25-125 U/L
AST 8-20 U/L
Bilirubin, serum (adult) Total // Direct 0.1-1.0 mg/dL // 0.0-0.3 mg/dL
Calcium, serum (Ca2+) 8.4-10.2 mg/dL
Cholesterol, serum Rec: < 200 mg/dL
Cortisol, serum 0800 h: 5-23 μg/dL //1600 h:
3-15 μg/dL
2000 h: ≤ 50% of 0800 h
Creatine kinase, serum Male: 25-90 U/L
Female: 10-70 U/L
Creatinine, serum 0.6-1.2 mg/dL
Electrolytes, serum  
Sodium (Na+) 136-145 mEq/L
Chloride (Cl-) 95-105 mEq/L
Potassium (K+) 3.5-5.0 mEq/L
Bicarbonate (HCO3-) 22-28 mEq/L
Magnesium (Mg2+) 1.5-2.0 mEq/L
Estriol, total, serum (in pregnancy)  
24-28 wks // 32-36 wks 30-170 ng/mL // 60-280 ng/mL
28-32 wk // 36-40 wks 40-220 ng/mL // 80-350 ng/mL
Ferritin, serum Male: 15-200 ng/mL
Female: 12-150 ng/mL
Follicle-stimulating hormone, serum/plasma Male: 4-25 mIU/mL
Female: premenopause: 4-30 mIU/mL
midcycle peak: 10-90 mIU/mL
postmenopause: 40-250
pH 7.35-7.45
PCO2 33-45 mmHg
PO2 75-105 mmHg
Glucose, serum Fasting: 70-110 mg/dL
2-h postprandial:<120 mg/dL
Growth hormone - arginine stimulation Fasting: <5 ng/mL
Provocative stimuli: > 7ng/mL
Immunoglobulins, serum  
IgA 76-390 mg/dL
IgE 0-380 IU/mL
IgG 650-1500 mg/dL
IgM 40-345 mg/dL
Iron 50-170 μg/dL
Lactate dehydrogenase, serum 45-90 U/L
Luteinizing hormone, serum/plasma Male: 6-23 mIU/mL
Female: follicular phase: 5-30 mIU/mL
midcycle: 75-150 mIU/mL
postmenopause 30-200 mIU/mL
Osmolality, serum 275-295 mOsmol/kd H2O
Parathyroid hormone, serume, N-terminal 230-630 pg/mL
Phosphatase (alkaline), serum (p-NPP at 30° C) 20-70 U/L
Phosphorus (inorganic), serum 3.0-4.5 mg/dL
Prolactin, serum (hPRL) < 20 ng/mL
Proteins, serum  
Total (recumbent) 6.0-7.8 g/dL
Albumin 3.5-5.5 g/dL
Globulin 2.3-3.5 g/dL
Thyroid-stimulating hormone, serum or plasma .5-5.0 μU/mL
Thyroidal iodine (123I) uptake 8%-30% of administered dose/24h
Thyroxine (T4), serum 5-12 μg/dL
Triglycerides, serum 35-160 mg/dL
Triiodothyronine (T3), serum (RIA) 115-190 ng/dL
Triiodothyronine (T3) resin uptake 25%-35%
Urea nitrogen, serum 7-18 mg/dL
Uric acid, serum 3.0-8.2 mg/dL
Hematologic Reference Range
Bleeding time 2-7 minutes
Erythrocyte count Male: 4.3-5.9 million/mm3
Female: 3.5-5.5 million mm3
Erythrocyte sedimentation rate (Westergren) Male: 0-15 mm/h
Female: 0-20 mm/h
Hematocrit Male: 41%-53%
Female: 36%-46%
Hemoglobin A1c ≤ 6 %
Hemoglobin, blood Male: 13.5-17.5 g/dL
Female: 12.0-16.0 g/dL
Hemoglobin, plasma 1-4 mg/dL
Leukocyte count and differential  
Leukocyte count 4,500-11,000/mm3
Segmented neutrophils 54%-62%
Bands 3%-5%
Eosinophils 1%-3%
Basophils 0%-0.75%
Lymphocytes 25%-33%
Monocytes 3%-7%
Mean corpuscular hemoglobin 25.4-34.6 pg/cell
Mean corpuscular hemoglobin concentration 31%-36% Hb/cell
Mean corpuscular volume 80-100 μm3
Partial thromboplastin time (activated) 25-40 seconds
Platelet count 150,000-400,000/mm3
Prothrombin time 11-15 seconds
Reticulocyte count 0.5%-1.5% of red cells
Thrombin time < 2 seconds deviation from control
Plasma Male: 25-43 mL/kg
Female: 28-45 mL/kg
Red cell Male: 20-36 mL/kg
Female: 19-31 mL/kg
Cerebrospinal Fluid Reference Range
Cell count 0-5/mm3
Chloride 118-132 mEq/L
Gamma globulin 3%-12% total proteins
Glucose 40-70 mg/dL
Pressure 70-180 mm H2O
Proteins, total < 40 mg/dL
Sweat Reference Range
Chloride 0-35 mmol/L
Calcium 100-300 mg/24 h
Chloride Varies with intake
Creatinine clearance Male: 97-137 mL/min
Female: 88-128 mL/min
Estriol, total (in pregnancy)  
30 wks 6-18 mg/24 h
35 wks 9-28 mg/24 h
40 wks 13-42 mg/24 h
17-Hydroxycorticosteroids Male: 3.0-10.0 mg/24 h
Female: 2.0-8.0 mg/24 h
17-Ketosteroids, total Male: 8-20 mg/24 h
Female: 6-15 mg/24 h
Osmolality 50-1400 mOsmol/kg H2O
Oxalate 8-40 μg/mL
Potassium Varies with diet
Proteins, total < 150 mg/24 h
Sodium Varies with diet
Uric acid Varies with diet
Body Mass Index (BMI) Adult: 19-25 kg/m2

(M1.MK.48) A 22-year-old female presents to a dermatologist concerned about the formation of several bald spots on her scalp that have developed over the last 6 weeks. She denies any past medical history; however, she reports a family history of a similar hair loss pattern in her maternal uncle. Physical examination reveals the patient's scalp as shown in Figure A. The patient asks her physician about the prognosis of this disease. Which of the following statements is true about this patient's presenting condition? Review Topic

QID: 102989

Treatment strategies are ineffective at inducing hair regrowth




Hair loss often recurs after successful treatment or spontaneous resolution




Topical immunotherapy is the first-line treatment option and is effective for all patients with the disease




Treatment with minoxidil is likely to be curative, with permanent resolution of hair loss




Spontaneous resolution rarely occurs




Select Answer to see Preferred Response


(M1.MK.46) A 19-year-old male presents to a dermatologist with a concern of patchy hair loss resulting in several areas of baldness on his scalp (Figure A). These bald spots have manifested over the last 2 months. There is no notable scaling, inflammation, or scarring associated with these patches. Which of the following conditions is associated with this patient's presentation? Review Topic

QID: 102987

Non-insulin dependent diabetes




Migraine headaches








Gonococcal arthritis




Autoimmune thyroiditis




Select Answer to see Preferred Response

Topic COMMENTS (2)
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