Fanconi anemia

Fanconi anemia is a rare disorder characterized by progressive bone marrow failure, various congenital abnormalities, and predisposition to malignancies (often acute myeloid leukemia). Bone marrow failure usually results in decreased production of all blood cells. It is considered the commonest type of inherited marrow failure syndrome ^7,11. It is almost invariably inherited in an autosomal recessive pattern.

Terminology

Fanconi anemia should not be confused with Fanconi syndrome which is a renal disease. 

Epidemiology

The estimated incidence is ~1:35,000 births. There may be a higher frequency in Ashkenazi Jews and Afrikaners in South Africa. There might also be a slight male predilection. 

Associations

• horseshoe kidney ⁶
• endocrine abnormalities
  • hypothyroidism
  • short stature
  • growth hormone deficiency ¹⁰
• hepatic tumors ¹²
• squamous cell carcinomas
  • esophagus
  • vulva
  • oropharynx ¹²

Pathology

Genetics

It is mostly transmitted by autosomal recessive inheritance (>99%).

Classification 

At least 13 genetic subtypes are described:

• type a
• type b
• type c
• type d1
• type d2
• type e
• type f
• type g
• type i 
• type j 
• type l
• type m
• type n

Radiographic features

Although non-specific, commonly described features include:

• radial ray anomalies: including absent thumb
• triphalangeal thumb
• congenital hip dysplasia
• scoliosis
• vertebral anomalies

Treatment and prognosis

The main cause of mortality is from marrow failure. Treatments include transfusion of blood products and bone marrow transplants. As most cases are inherited, genetic counseling is important.

History and etymology

First described by a Swiss pediatrician, Guido Fanconi (1892-1979), in 1927 ^8,9.