Bloom Syndrome Definition
Table Of Content:
It is a rare form of inherited disorder that is also known as ‘Bloom-Torre-Machacek syndrome’. This condition was first described and discovered by the New York dermatologist Dr. David Bloom in 1954. This is an autosomal recessive disorder which manifests itself with several breaks and rearrangements in the chromosomes of the patient. Damage to the DNA maximizes the risk of multiple cancers in the initial years of life.
Bloom Syndrome Causes
The mutations in the BLM lead to this syndrome. The BLM gene offers directions for producing a family of proteins called the RecQ helicases. Helicases are enzymes which adhere to DNA and unwind the two spiral strands of the DNA molecule. The unwinding of the strands is essential for copying DNA that will prepare for cell division and also for correcting the damages of the destroyed DNA. This protein maintains the structure and integrity of DNA. If the BLM gene gets altered, the BLM protein is hindered from performing its function of ensuring genomic stability. This leads to an increase of sister chromatid exchange to 10 fold. This chromosomic instability causes gaps and breaks in the genetic material which leads to defects in the normal cell activities and lead to health problems.
This condition is inherited in an autosomal recessive pattern and this implies that both copies of the gene in each cell have alterations. The parents of the child with an autosomal recessive condition will carry one copy of the altered gene but usually they do not show any symptoms of the condition.
Bloom Syndrome Symptoms
The disorder gives rise to the following symptoms:
- Short stature
- Development of rashes on skin areas exposed to sunlight.
- Development of infiltrated scaly skin rashes that take the shape of butterfly. These arise on patches of skin over the nose and cheeks.
- High pitched voice
- Alterations in facial features such as long, narrow face, prominent nose and ears.
- Skin pigmentation which includes hypo and hyper pigmented areas that appears in the eyes as well.
- Mild immune deficiency
- Recurrent pneumonia
- Ear infections
- Hypogonadism, or inability to produce sperms, resulting in infertility in males.
- Early onset as well as early stoppage of menstruation which leads to infertility in females.
- Risk of developing cancer.
- Mild mental retardation
- Possibility of Diabetes mellitus
Bloom Syndrome Diagnosis
A physician who is an expert in identifying the symptoms may suggest for special chromosome testing or testing of the Bloom Syndrome gene. Prenatal diagnosis can be done for couples who are carriers of the mutated gene.
Bloom Syndrome Treatment
There is no treatment available to make the genome in the cells stable and block the abnormal mutations. However, children who have poor feeding habits and have been suffering from gastro-esophageal reflux will require non-volitional feeding. It can increase the deposition of fat in infants. The facial skin patches will have to be protected from sunlight by avoiding sunlight and the usage of head cover and sunscreens. The middle ear infection, pneumonia and respiratory tract infections should be treated with antibiotics so that the lungs do not get damaged severely.
Physicians should check patients frequently for a possible progression of cancer. Diagnostic methods such as mammography, pap smears and colonoscopy should be done in the early stages. Bone marrow transplantation is helpful in the treatment of cancer. If the sib is genetically identical, a marrow can be donated. Non-BS pregnancies are also possible if stem cells are harvested from the placental blood and are stored in a freezing environment. Malignant cases of cancer need surgical oncological treatment. Patients are also likely to need the support of a health team of dermatologist to offer guidance to the family regarding sun protection, an oncologist for cancer check-ups and endocrinologist for short stature and hypogonadism throughout their lifetime.
Bloom Syndrome Prognosis
Patients with neoplasms arising due to this condition have the maximum risk of early death in the second or third decade which comes just after malignant cases. The various types of leukemia often occur at an average age of 22 years. Patient who live after the age of 22 years tend to develop solid tumors at the age of 35 years. However, these tumors are susceptible to chemotherapy and radiotherapy. Patients get immune to infections with increasing age. Erythema and sensitivity to sunlight also improve with age.
Bloom Syndrome Complications
The complications of this disorder include:
- Chronic lung defects
- Inability to learn
- Mental retardation
- Occurrence of cancer, which leads to cell getting divided in an uncontrolled manner
- Increased level of activity of BLM protein, which lead to maximum number of cell deaths that slows down the growth.
Bloom Syndrome Pictures
These images will help you understand how this disorder alters the physical appearance of its sufferers.
Picture 1 – Bloom Syndrome
Picture 2 – Bloom Syndrome Image