Leukemia, and Malabsorption

Mastocytosis, or mast cell disease, is a heterogeneous group of clinical disorders characterized by the abnormal accumulation of mast cells in various tissues, especially in the skin and hematopoietic organs. Mastocytosis usually appears in infancy or early adulthood. In most pediatric cases, the disease is limited to the skin, but it can be associated with systemic symptoms due to the release of mediators from mast cells, even when there is no systemic infiltration. It usually has a good prognosis, with substantial improvement or spontaneous resolution before puberty. In rare cases, the disease may remain active through adolescence as a systemic adult mastocytosis. Cutaneous mastocytosis is characterized by macules, papules, nodules, or diffuse infiltration of the skin, often associated with localized hyperpigmentation. Gentle rubbing of the lesions induces histamine release from mechanically activated mast cells, causing local wheals, erythema, and often pruritus, a phenomenon termed the 'Darier sign.' In contrast to childhood-onset mastocytosis, adult-onset mastocytosis often persists for the lifetime of the patient and is also more likely to be a severe and systemic disease involving numerous organs. In some cases, it is associated with a clonal hematologic non-mast-cell lineage disease, such as a myelodysplastic or myeloproliferative disorder. Adult-onset mastocytosis can also lead to the rare mast cell leukemia, which carries a high risk of mortality (summary by Bodemer et al., 2010 and Kambe et al., 2010).

MASTOCYTOSIS, CUTANEOUS; MASTC Is also known as mastocytosis, maculopapular cutaneous|mastocytosis, diffuse cutaneous|urticaria pigmentosa

• Neoplasm
• Pain
• Anemia
• Hypertension
• Hepatomegaly

SOURCES: OMIM ORPHANET MENDELIAN

LIG4 syndrome is a hereditary disorder associated with impaired DNA double-strand break repair mechanisms and characterized by microcephaly, unusual facial features, growth and developmental delay, skin anomalies, and pancytopenia, which is associated with combined immunodeficiency (CID).

LIG4 SYNDROME Is also known as dna ligase iv deficiency|ligase 4 syndrome

• Intellectual disability
• Global developmental delay
• Microcephaly
• Growth delay
• Micrognathia

SOURCES: OMIM MESH ORPHANET MENDELIAN

Waldenström macroglobulinemia (WM) is an indolent B-cell lymphoproliferative disorder characterized by the accumulation of monoclonal cells in the bone marrow and peripheral lymphoid tissues, and associated with the production of serum immunoglobulin M (IgM) monoclonal protein.

• Hearing impairment
• Ataxia
• Neoplasm
• Anemia
• Peripheral neuropathy

SOURCES: OMIM ORPHANET MENDELIAN

Shwachman-Diamond syndrome (SDS) is a rare multisystemic syndrome characterized by chronic and usually mild neutropenia, pancreatic exocrine insufficiency associated with steatorrhea and growth failure, skeletal dysplasia with short stature, and an increased risk of bone marrow aplasia or leukemic transformation.

SHWACHMAN-DIAMOND SYNDROME Is also known as pancreatic insufficiency and bone marrow dysfunction|shwachman syndrome|shwachman-bodian syndrome|shwachman-diamond syndrome|shwachman-bodian-diamond syndrome|sds|lipomatosis of pancreas, congenital

• Intellectual disability
• Global developmental delay
• Short stature
• Generalized hypotonia
• Scoliosis

SOURCES: OMIM ORPHANET MENDELIAN

Mevalonic aciduria (MVA) is a rare, very severe form of mevalonate kinase deficiency (MKD; see this term) characterized by dysmorphic features, failure to thrive, psychomotor delay, ocular involvement, hypotonia, progressive ataxia, myopathy, and recurrent inflammatory episodes.

MEVALONIC ACIDURIA Is also known as mva|complete mevalonate kinase deficiency

• Intellectual disability
• Seizures
• Global developmental delay
• Short stature
• Generalized hypotonia

SOURCES: OMIM ORPHANET MENDELIAN

Dyskeratosis congenita (DC) is a rare ectodermal dysplasia that often presents with the classic triad of nail dysplasia, skin pigmentary changes, and oral leukoplakia associated with a high risk of bone marrow failure (BMF) and cancer.

DYSKERATOSIS CONGENITA Is also known as dkc|dc|dyskeratosis congenita, scoggins type|zinsser-engman-cole syndrome

• Global developmental delay
• Short stature
• Hearing impairment
• Microcephaly
• Scoliosis

SOURCES: ORPHANET MESH OMIM MENDELIAN

Dubowitz syndrome (DS) is a rare multiple congenital syndrome characterized primarly by growth retardation, microcephaly, distinctive facial dysmorphism, cutaneous eczema, a mild to severe intellectual deficit and genital abnormalities.

• Intellectual disability
• Seizures
• Short stature
• Hearing impairment
• Microcephaly

SOURCES: ORPHANET MENDELIAN

Neurofibromatosis type I is an autosomal dominant disorder characterized by cafe-au-lait spots, Lisch nodules in the eye, and fibromatous tumors of the skin. Individuals with the disorder have increased susceptibility to the development of benign and malignant tumors. NF1 is sometimes referred to as 'peripheral neurofibromatosis.' The worldwide incidence of NF1 is 1 in 2,500 to 1 in 3,000 individuals (reviews by Shen et al., 1996 and Williams et al., 2009).Type II neurofibromatosis (NF2 ) is a genetically distinct disorder caused by mutation in the gene encoding merlin (NF2 ) on chromosome 22q12. NF2, sometimes known as 'central neurofibromatosis,' is characterized by bilateral acoustic neuroma and meningioma, but few skin lesions or neurofibromas (Rouleau et al., 1993).Some patients with homozygous or compound heterozygous mutations in mismatch repair genes (see, e.g., MLH1; {120436} and MSH2; {609309}) have a phenotype characterized by early onset malignancies and mild features of NF1, especially cafe-au-lait spots; this is known as the mismatch repair cancer syndrome (OMIM ), sometimes referred to as brain tumor-polyposis syndrome-1 or Turcot syndrome. These patients typically do not have germline mutations in the NF1 gene, although a study by Wang et al. (2003) suggested that biallelic mutations in mismatch repair genes may cause somatic mutations in the NF1 gene, perhaps resulting in isolated features resembling NF1.See also Legius syndrome (OMIM ), a genetically distinct disorder with a similar phenotype to NF1.

NEUROFIBROMATOSIS TYPE 1 DUE TO NF1 MUTATION OR INTRAGENIC DELETION Is also known as von recklinghausen disease due to nf1 mutation or intragenic deletion|neurofibromatosis, peripheral type|von recklinghausen disease

• Intellectual disability
• Seizures
• Short stature
• Scoliosis
• Hypertelorism

SOURCES: ORPHANET OMIM MENDELIAN

The thrombocytopenia-absent radius syndrome (TAR) is characterized by reduction in the number of platelets and absence of the radius; preservation of the thumb distinguishes TAR from other syndromes that combine blood abnormalities with absence of the radius, such as Fanconi anemia (see {227650}). Individuals with TAR have low numbers of megakaryocytes, platelet precursor cells that reside in bone marrow, and frequently present with bleeding episodes in the first year of life that diminish in frequency and severity with age. The severity of skeletal anomalies varies from absence of radii to virtual absence of upper limbs, with or without lower limb defects such as malformations of the hip and knee (summary by Albers et al., 2012).

THROMBOCYTOPENIA-ABSENT RADIUS SYNDROME; TAR Is also known as tar syndrome|chromosome 1q21.1 deletion syndrome, 200-kb

• Intellectual disability
• Seizures
• Global developmental delay
• Short stature
• Hearing impairment

SOURCES: ORPHANET OMIM MENDELIAN

Cartilage-hair hypoplasia is a disease affecting the bone metaphyses causing small stature from birth.

CARTILAGE-HAIR HYPOPLASIA Is also known as autosomal recessive metaphyseal chondrodysplasia|metaphyseal chondrodysplasia, mckusick type

• Intellectual disability
• Short stature
• Scoliosis
• Growth delay
• Neoplasm

SOURCES: OMIM ORPHANET MENDELIAN