You are currently viewing Aromatase Excess Syndrome :‎ Medical Notes & Mindmap

Aromatase excess syndrome is a rare genetic disorder that happens when the enzyme aromatase is made in too large of a quantity. This enzyme is what changes androgens, which are male hormones, into oestrogens (female hormones).

People with aromatase excess syndrome have too much aromatase in their bodies, which makes them have high levels of oestrogen and low levels of androgens.

This can cause a number of symptoms, such as early puberty, weight gain, and bigger breast tissue in men. Some treatments include drugs that stop the body from making aromatase and hormone therapy to get the levels of androgens back to normal.

Aromatase Excess Syndrome :‎ [MEDNOTES+MINDMAP]

  • Definition:

    • A metabolic disorder characterized by an overproduction of estrogen in females and low levels of testosterone in males, caused by an increased activity of the enzyme aromatase.

  • Epidemiology:

    • More commonly seen in females
    • Prevalence is unknown
    • Can occur in any age group
    • Can be inherited or acquired
  • Natural history:

    • Symptoms typically begin to appear during puberty
    • Can lead to a variety of physical and psychological symptoms, including:
      • Excess body fat
      • Enlarged breasts
      • Irregular menstrual cycles
      • Infertility
      • Depression
      • Anxiety
      • Cognitive impairment
  • Classification/Types/Stages:

    • Primary Aromatase Excess Syndrome: caused by a genetic mutation that leads to increased aromatase activity
    • Secondary Aromatase Excess Syndrome: caused by an underlying medical condition or medication that increases aromatase activity
    • Stage 1: mild symptoms, such as irregular menstrual cycles
    • Stage 2: moderate symptoms, such as enlarged breasts and excess body fat
    • Stage 3: severe symptoms, such as infertility and cognitive impairment.
  • Risk Factors : 

    • Genetic mutations in the CYP19A1 gene (encodes for aromatase enzyme)
    • Obesity
    • Polycystic ovary syndrome (PCOS)
    • Excessive exposure to estrogen
  • Etiology/Causes : 

    • Aromatase enzyme converts androgens (such as testosterone) to estrogen
    • In Aromatase Excess Syndrome, there is an overproduction of aromatase enzyme leading to excessive estrogen production
    • This can occur due to genetic mutations in the CYP19A1 gene or due to other factors such as obesity or PCOS
  • Signs : 

    • Gynecomastia (enlargement of breast tissue in males)
    • Feminization (such as decreased body hair and increased breast size)
    • Infertility
    • Elevated estrogen levels in blood tests
  • Symptoms :

    • Fatigue
    • Hot flashes
    • Mood changes
    • Irregular menstrual cycles
    • Headaches
    • Decreased sex drive
  • Pathology/Pathogenesis :

    • Excessive estrogen production leads to a variety of hormonal imbalances and symptoms
    • This can also lead to increased risk of certain cancers, such as breast cancer


  • Diagnosis :

    • Elevated estrogen levels
    • Elevated estradiol levels
    • Elevated estrone levels
    • Low levels of androgens
    • Genetic testing for CYP19A1 mutations
  • Tests Required :

    • Blood tests for hormone levels
    • Genetic testing
    • Ultrasound or MRI to assess for ovarian or adrenal tumors
  • Associated with :

    • Ovarian or adrenal tumors
    • Polycystic ovary syndrome (PCOS)
    • Obesity
    • Insulin resistance
  • Similar diseases/syndromes :

    • Congenital adrenal hyperplasia (CAH)
    • Estrogen-secreting tumors
    • Hypogonadism
  • Treatment :

    • Surgery to remove ovarian or adrenal tumors
    • Medications to decrease estrogen production (such as anastrozole or letrozole)
    • Hormone replacement therapy to increase androgen levels
    • Weight loss and exercise to improve insulin resistance and obesity-related symptoms
    • Close monitoring of hormone levels and tumors with regular follow-up appointments.

Dr. Arin Nandi

Passionate About Medical Science & Helping Future Doctors Achieve Top Ranks In Medical Exams. He is professionally a dentist as well as a public health expert from JIPMER working in department