What is Bloom syndrome?

Bloom syndrome is a rare hereditary disease associated with an increased risk of cancer. The most striking characteristic is retarded growth, which may already begin during pregnancy and can persist through infancy and childhood into adulthood. Noticeable reddening of the skin in areas exposed to sunlight, especially in the face, is also common.

How is Bloom syndrome diagnosed?

Typical characteristics of Bloom syndrome

There are a number of common characteristics with Bloom syndrome, specifically:

  • Retarded growth during pregnancy, persisting during infancy and childhood

  • Reduced subcutaneous fatty tissue

  • Dwarfism

  • Hypersensitivity to sunlight

  • Reddening of the face (symmetric = butterfly rash)

  • Immunodeficiency

  • Acid reflux (gastroesophageal reflux)

  • Frequent infections, especially in the upper airways

  • Chronically obstructive airway diseases

  • Learning disorders / low intelligence (not universal)

  • Premature loss of ovarian function in women

  • Limited fertility or infertility in men

  • Narrowing of the urinary tract in men

  • Type II diabetes mellitus

The existence of Bloom syndrome should be suspected when the following indicative combination of findings is found:

  • Unexplained severely retarded growth during pregnancy that persists through infancy and childhood until adolescence

  • Significantly retarded growth and reddish skin changes in the facial area after exposure to sunlight (butterfly rash)

  • Considerably retarded growth and a tumor diagnosis

Genetic Diagnostics

Bloom syndrome can be diagnosed based on its characteristic clinical presentation and confirmed by genetic analysis.

What is the risk of cancer?

The following tumor diagnoses are most commonly associated with Bloom syndrome:

  • Blood cancer (leukemia: acute lymphatic leukemia and acute myeloid leukemia)

  • Tumors of the lymphatic tissue (lymphomas)

  • Tumors of the gastrointestinal tract (colorectal tumors)

  • Soft tissue tumors (sarcomas)

  • Tumors of the genital and urinary tract

  • Breast cancer

  • Kidney tumors (nephroblastomas)

  • Brain tumors (medulloblastomas)

  • Eye tumors (retinoblastomas)

  • Germ cell tumors

Many tumors develop with the same distribution pattern as in the healthy population but with an earlier onset time.

What causes Bloom syndrome?

The increased risk of tumors is explained by genetic damage, which is due to structural DNA instability, and leads to an increased rate of spontaneous mutations, i.e. alters the genetic information.

Is there a treatment?

The treatment predominantly consists of diagnosing preliminary cancer stages as early as possible. Treatment is in line with the corresponding treatment recommendation. Doses and the duration of treatment may need to be adjusted due to heightened sensitivity of the cells to ionizing radiation and DNA-damaging substances.

Surveillance Recommendations for the Early Detection of Cancer

Surveillance Recommendations

Regular physical examinations are recommended, these include checking for physical growth and the frequency of infections. Annual laboratory testing, an annual skin examination, and a six-monthly dental examination should also be performed.

Evidence-based standards are lacking for early detection, particularly during childhood. The following are the consensus recommendations of the American Association for Cancer Research:

  • Hematology-oncology:

    • Medical history and a physical examination
    • Avoidance of exposure to radiation
    • Blood count every 3-4 months
    • Breast MRI and ultrasound from 18 years of age
    • Annual colonoscopy from 10-12 years of age
    • Stool test every 6 months
    • Ultrasound of the kidneys every 3 months after diagnosis until age 8 (screening for nephroblastoma)
    • HPV vaccination

  • Dermatology:

    • Annual skin examination
    • Limit exposure to sunlight!

  • Pulmonology:

    • Lung function testing according to clinical need
    • Aggressive antibiotic treatment after an antibiogram

  • Gastroenterology/nutrition:

    • Basic examination
    • Swallowing tests as needed
    • Dietary supplementation

  • Endocrinology:

    • Annual TSH, T3, T4
    • Annual glucose test on an empty stomach and a lipid profile from the age of 10

  • Orthopedics:

    • Annual scoliosis examination

  • Dental:

    • Six-monthly checkups

Self-Care and Support

What should I pay special attention to?

Avoid sunlight exposure, especially on the face.

Magnetic resonance imaging (MRI) and ultrasound are preferred to X-rays and computer tomography (CT) for diagnostics.

Support Groups and Additional Information