Down Syndrome (Trisomy 21): Complications

The following are the most important conditions or complications that may be contributed to by Down syndrome (trisomy 21):

Congenital malformations, deformities, and chromosomal abnormalities (Q00-Q99).

  • Malformations of the gastrointestinal tract – prevalence (disease incidence): 7%.
    • Hirschsprung’s disease (MH; synonym: megacolon congenitum) – genetic disorder with both autosomal recessive inheritance and sporadic occurrence; disorder affecting the last third of the colon (sigmoid and rectum) in most cases; belongs to the group of aganglionoses (absence of ganglion cells) in the submucosal plexus or myentericus (Auerbach’s plexus); leads to hyperplasia of the upstream nerve cells, which leads to increased acetylcholine release; due to the permanent stimulation of the ring muscles, it thus comes to a permanent contraction of the affected intestinal section
  • Absence of the patellae – rarity.
  • Genu valgum (knock-kneed) – prevalence: 22%.
  • Cardiac vitia (heart defect) – about 50% of newborns.
  • Hip abnormalities – prevalence: about 8%.
  • Congenital hypothyroidism (congenital hypothyroidism).
  • Pes cavus (hollow foot)
  • Pes planus (flat foot) – prevalence: 60%.
  • Pes valgus (bent foot) – prevalence: 24 %.
  • Pronation (inward rotation) of the foot – prevalence: 16%.

Respiratory system (J00-J99)

  • Reactive airway disease (bronchial asthma, active bronchospasm) – prevalence: 32%.

Endocrine, nutritional, and metabolic diseases (E00-E90).

Skin and subcutaneous (L00-L99).

  • Alopecia areata (circular hair loss) – prevalence: 2.5-11%
  • Cheilitis (inflammation of the lips) – prevalence (disease frequency): 20% in children and adolescents.
  • Elastosis perforans serpiginose (EPS; characterized by transepidermal elimination of abnormal elastic fibers) – specific for Down syndrome.
  • Wrinkled or furrowed tongue – prevalence (disease incidence): 28% in children and adolescents.
  • Fine, thin hair – prevalence (disease frequency): 27.4% in children and adolescents.
  • Hypertrophy (enlargement) of the papillae of the tongue – prevalence: 22% in children and adolescents.
  • Keratosis pilaris (rubbing iron-like scale-covered nodules) – prevalence: 4% in children and adolescents.
  • Lichenification (extensive leathery change of the skin) – prevalence: 52.6% in children and adolescents.
  • Livedo reticularis (reticular bluish-purple drawing of the skin, following the course of vessels) – prevalence: 2% in children and adolescents.
  • Milia-like calcinosis cutis (MLCC; pathological (pathological) deposition of calcium salts resembling a skin gravel)) – specific for Down syndrome.
  • Multiple eruptive dermatofibromas (MED) (benign proliferation of connective tissue cells) – for Down syndrome specific.
  • Palmoplantar hyperkeratosis (wart-like thickening on palms and soles) – prevalence (disease incidence): 10% in children and adolescents.
  • Seborrheic eczema (greasy scales on redness in regions rich in sebaceous glands) – prevalence (disease frequency): 3% in children and adolescents.
  • Trichotillomania (hair plucking: compulsive pulling out their own hair) – prevalence (disease frequency): 4% in children and adolescents.
  • Vitiligo (white spot disease) – prevalence (disease frequency): 3% in children and adolescents.
  • Premature graying – prevalence (disease frequency): 14% in children and adolescents.
  • Xerosis (skin dryness)

Mouth, esophagus (esophagus), stomach, and intestines (K00-K67; K90-K93).

  • Chronic idiopathic constipation (constipation) – difficult bowel evacuation, unknown cause, in which bowel movements are regularly absent for more than four days.
  • Lingua geographica (map tongue): harmless alteration of the tongue surface; constitutional anomaly; the tongue gets its typical appearance by shedding of the epithelium of the filiform papillae of the tongue surface (papillae filiformes); whitish and reddish districts resembling a map appear; spectrum of symptoms ranges from asymptomatic to a burning sensation or burning pain; prevalence (disease frequency): 4% in children and adolescents
  • Celiac disease (chronic disease of the mucosa of the small intestine (small intestinal mucosa) due to hypersensitivity to the cereal protein gluten (gluten intolerance) – prevalence (disease frequency): (4,5-7 %) [1,2]

Musculoskeletal system and connective tissue (M00-M99).

  • Atlantoaxial instability (AAI; instability of the second upper cervical joint).
  • Juvenile idiopathic arthritis (JIA; synonyms: juvenile rheumatoid arthritis (JRA), juvenile chronic arthritis, JCA), oligoarticular – prevalence: 0.2%.
  • Scoliosis (lateral bending of the spine with simultaneous rotation (twisting) of the vertebrae) – prevalence: about 9%.

Neoplasms – tumor diseases (C00-D48).

  • Acute leukemias: The risk of developing acute leukemia is increased 14 to 20-fold in children with Down syndrome (compared with the normal population)
  • Syringomas – benign (benign) tumors of the sweat gland excretory ducts; specific for Down syndrome – prevalence: 18.5%.
  • Transient leukemia – occurs in 5-10% in the neonatal period; found exclusively in children with Down syndrome.

Ears – mastoid process (H60-H95).

Psyche – nervous system (F00-F99; G00-G99).

  • Autism – refers to a person’s seclusion from the outside world. Affected individuals encapsulate themselves in their own world of thought and imagination.
  • Dementia
    • By age 55, 2 out of 3 people with Down syndrome are receiving medical treatment for dementia.
    • Dementia 20 times more likely to be the cause of death than in the general population; approximately 70% of patients with Down syndrome die of dementia; among those with dementia, those with an ApoE4 allele were most likely to die (7-fold increased risk of death).
  • Depression
  • Obsessive-compulsive disorder

Further

  • Hip instability
  • Increased gait instability
  • Increased hypermobility
  • Visual problems – prevalence: 85% in children and adolescents; increases with age.

Note: All prevalences (disease frequencies) given above refer to patients with Down syndrome.