Skeletal dysplasia-T-cell immunodeficiency-developmental delay syndrome

What it is

From: Orphanet

A rare genetic multiple congenital anomalies/dysmorphic syndrome characterized by the association of developmental delay, variable intellectual disability, skeletal dysplasia, and in many cases T-cell immunodeficiency and other immunologic abnormalities. Skeletal findings include short stature, anomalies of the long bones, hands and feet, and pelvis, platyspondyly, cervical malformation, and pectus excavatum. Dysmorphic facial features, such as coarse face, hypertelorism, and broad nasal tip, may be present. Additional reported manifestations are seizures, hyperreflexia, nystagmus, and muscular hypotonia, as well as multiple liver cysts.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Abnormality of the skeletal system · Very frequent (99-80%)

An abnormality of the skeletal system.

Global developmental delay · Very frequent (99-80%)

A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.

Motor delay · Very frequent (99-80%)

A type of Developmental delay characterized by a delay in acquiring motor skills.

Severe platyspondyly · Very frequent (99-80%)

Abnormal facial shape · Frequent (79-30%)

An abnormal morphology (form) of the face or its components.

Abnormal thorax morphology · Frequent (79-30%)

Any abnormality of the thorax (the region of the body formed by the sternum, the thoracic vertebrae and the ribs).

Abnormality of limb bone morphology · Frequent (79-30%)

Any abnormality of bones of the arms or legs.

Abnormality of the cervical spine · Frequent (79-30%)

Any abnormality of the cervical vertebral column.

Abnormality of the ilium · Frequent (79-30%)

An abnormality of the ilium, the largest and uppermost bone of the pelvis.

Acetabular dysplasia · Frequent (79-30%)

A smaller than normal acetabulum that has insufficient femoral head coverage leading to abnormal hip joint contact pressures, instability and pain.

Brachydactyly · Frequent (79-30%)

Digits that appear disproportionately short compared to the hand/foot. The word brachydactyly is used here to describe a series distinct patterns of shortened digits (brachydactyly types A-E). This is the sense used here.

Broad metacarpals · Frequent (79-30%)

Abnormally broad metacarpal bones.

Broad phalanges of the hand · Frequent (79-30%)

Increased width of the phalanges of the hand.

Decreased circulating antibody level · Frequent (79-30%)

An abnormally decreased level of immunoglobulin in blood.

Other findings in the same source

From: Orphanet

Additional reported features include Decreased lymphocyte proliferation in response to mitogen (Frequent (79-30%)); Decreased total T cell count (Frequent (79-30%)); Delayed ability to sit (Frequent (79-30%)); Disproportionate short stature (Frequent (79-30%)); Frontal bossing (Frequent (79-30%)); Hypereosinophilia (Frequent (79-30%)); Hypoplasia of the odontoid process (Frequent (79-30%)); Hyporeflexia (Frequent (79-30%)); Hypotonia (Frequent (79-30%)); Intellectual disability (Frequent (79-30%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Antenatal; Neonatal

Inheritance in the source

From: Orphanet

Autosomal recessive

Frequency and the population described

From: Orphanet

Reported case(s): 12.0; Worldwide. This is a published case count, not prevalence. Point prevalence: <1 / 1 000 000; Worldwide; Class only.

Understanding the inheritance label

From: MedlinePlus Genetics

An autosomal recessive pattern usually involves disease-causing changes in both copies of a gene. Parents may each carry one altered copy without having the condition themselves. A genetic counsellor can explain carrier testing and reproductive implications using the actual laboratory findings, rather than the condition name alone.

Which doctor should you see?

The suggested department for discussing Skeletal dysplasia-T-cell immunodeficiency-developmental delay syndrome is Orthopaedics, with a orthopaedic specialist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

Additional services that may be relevant, depending on the findings, include: Clinical Genetics.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• What explains the change in pain, movement or function?
• Which activities need adjustment while the diagnosis is being clarified?
• What are the roles of rehabilitation, observation and surgery in this situation?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Skeletal dysplasia-T-cell immunodeficiency-developmental delay syndrome. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.