Aase syndrome or Aase–Smith syndrome is a rare

inherited disorder A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. Although polygenic disorders ...

characterized by

anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, th ...

with some joint and

skeletal A skeleton is the structural frame that supports the body of an animal. There are several types of skeletons, including the exoskeleton, which is the stable outer shell of an organism, the endoskeleton, which forms the support structure inside ...

deformities. Aase syndrome is thought to be an

autosomal An autosome is any chromosome that is not a sex chromosome. The members of an autosome pair in a diploid cell have the same morphology, unlike those in allosome, allosomal (sex chromosome) pairs, which may have different structures. The DNA in au ...

dominant inherited disorder. The genetic basis of the disease is not known. The anemia is caused by underdevelopment of the

bone marrow Bone marrow is a semi-solid tissue found within the spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It is composed of hematopoietic ce ...

, which is where blood cells are formed. It is named after the American paediatricians Jon Morton Aase and

David Weyhe Smith David Weyhe Smith (September 24, 1926 – January 23, 1981) was an American pediatrician and dysmorphologist. Smith was born in Oakland, California. He gained his medical degree from Johns Hopkins School of Medicine and worked with Lawson Wilk ...

, who characterized it in 1968.

Signs and symptoms

Among the presentation are: * Mildly slowed growth * Pale skin * Delayed closure of fontanelles (soft spots) * Narrow shoulders * Triple jointed thumbs, absent or small knuckles, decreased skin creases at finger joints * Inability to fully extend the joints from birth (congenital contractures) *

Cleft palate A cleft lip contains an opening in the upper lip that may extend into the nose. The opening may be on one side, both sides, or in the middle. A cleft palate occurs when the palate (the roof of the mouth) contains an opening into the nose. The te ...

* Deformed ears * Droopy eyelids

Complications

* Complications related to anemia include weakness, fatigue, and decreased oxygenation of the blood. * Decreased white blood cells alter the body's ability to fight infection. * If a heart defect exists, it may cause multiple complications (depending on the specific defect). * Severe cases have been associated with still birth or early death.

Cause

Some cases of Aase syndrome (45%) have been shown to be inherited, and are due to a change in one gene which makes ribosomal proteins. However, many cases are not inherited and occur without a known cause.

Diagnosis

* A CBC (

complete blood count A complete blood count (CBC), also known as a full blood count (FBC), is a set of medical laboratory tests that provide cytometry, information about the cells in a person's blood. The CBC indicates the counts of white blood cells, red blood cell ...

) will show anemia and a decrease in the

white blood cell White blood cells, also called leukocytes or leucocytes, are the cell (biology), cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and de ...

count. * An

echocardiogram An echocardiography, echocardiogram, cardiac echo or simply an echo, is an ultrasound of the heart. It is a type of medical imaging of the heart, using standard ultrasound or Doppler ultrasound. Echocardiography has become routinely used in th ...

may reveal heart defects ( ventricular septal defect is most common). * X-rays will show skeletal abnormalities as described above. * A bone marrow

biopsy A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a diseas ...

may be performed.

Prevention

As with most genetic diseases there is no way to prevent the entire disease. With prompt recognition and treatment of infections in childhood, the complications of low white blood cell counts may be limited.

Treatment

Frequent

blood transfusion Blood transfusion is the process of transferring blood products into a person's circulation intravenously. Transfusions are used for various medical conditions to replace lost components of the blood. Early transfusions used whole blood, but mo ...

s are given in the first year of life to treat anemia. Prednisone may be given, although this should be avoided in infancy because of side effects on growth and brain development. A

bone marrow transplant Hematopoietic stem-cell transplantation (HSCT) is the transplantation of multipotent hematopoietic stem cells, usually derived from bone marrow, peripheral blood, or umbilical cord blood in order to replicate inside of a patient and to produce ...

may be necessary if other treatment fails.

Prognosis

Anemia usually resolves over the years.

References

External links

{{Medical resources , DiseasesDB = 29332 , ICD10 = , ICD9 = , ICDO = , OMIM = 147800 , MedlinePlus = 001662 , eMedicineSubj = , eMedicineTopic = , Orphanet = 916 Genetic disorders with OMIM but no gene Syndromes affecting blood Syndromes with cleft lip and/or palate