Schimke immuno-osseous dysplasia

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Schimke immuno-osseous dysplasia is a condition characterized by short stature, kidney disease, and a weakened immune system. People with this condition have flattened spinal bones (vertebrae) that shorten their neck and trunk. The adult height for people with this condition is typically between 3 and 5 feet. Additional skeletal problems in people with Schimke immuno-osseous dysplasia include abnormalities of the hip joints and the end of the leg bones where they meet the hip joint. These skeletal problems can cause the hip joints to break down (degenerate) over time, leading to joint pain and a limited range of movement. This combination of skeletal problems and spinal abnormalities is called spondyloepiphyseal dysplasia as it affects the bones of the spine (spondylo-) and the ends of long bones (epiphyses) in the legs. It affects most people with Schimke immuno-osseous dysplasia.People with Schimke immuno-osseous dysplasia often have kidney (renal) disease that may lead to life-threatening renal failure and end-stage renal disease (ESRD).

Individuals with Schimke immuno-osseous dysplasia also have a shortage of immune system cells called T cells. T cells identify foreign substances and defend the body against infection. This shortage of T cells causes people with Schimke immuno-osseous dysplasia to have recurrent infections.

Other features frequently seen in people with Schimke immuno-osseous dysplasia include an exaggerated curvature of the lower back (lordosis); darkened patches of skin (hyperpigmentation), typically on the chest and back; abnormalities of the teeth; and a broad nasal bridge with a rounded tip of the nose.

Less common signs and symptoms of Schimke immuno-osseous dysplasia include an accumulation of fatty deposits in the lining of the arteries (atherosclerosis), reduced blood flow to the brain (ischemic stroke), migraine-like headaches, an underactive thyroid gland (hypothyroidism), a decrease in the number of blood cells (anemia), a lack of sperm (azoospermia), and irregular menstruation.

In severe cases, individuals with Schimke immuno-osseous dysplasia do not survive past childhood. In mild cases, people with Schimke immuno-osseous dysplasia can survive into adulthood.

ORPHANET DEFINITION A rare a multisystem disorder characterized by spondyloepiphyseal dysplasia and disproportionate short stature, facial dysmorphism, T-cell immunodeficiency, and progressive, proteinuric steroid-resistant nephropathy.

Inheritance

From: MedlinePlus Genetics, National Library of Medicine

Autosomal recessive

Frequency in the source

From: MedlinePlus Genetics, National Library of Medicine

Reported case(s): 133.0; Worldwide. This is a published case count, not prevalence. Point prevalence: <1 / 1 000 000; Worldwide; Class only.

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.

Abnormal lymphocyte physiology · Very frequent (99-80%)

Any anomaly of lymphocyte function.

Abnormality of the femoral head · Very frequent (99-80%)

An abnormality of the femoral head.

Focal segmental glomerulosclerosis · Very frequent (99-80%)

Segmental accumulation of scar tissue in individual (but not all) glomeruli.

Intrauterine growth retardation · Very frequent (99-80%)

An abnormal restriction of fetal growth with fetal weight below the tenth percentile for gestational age.

Nephropathy · Very frequent (99-80%)

A nonspecific term referring to disease or damage of the kidneys.

Proteinuria · Very frequent (99-80%)

Increased levels of protein in the urine.

Short stature · Very frequent (99-80%)

A height below that which is expected according to age and gender norms. Although there is no universally accepted definition of short stature, many refer to "short stature" as height more than 2 standard deviations below the mean for age and gender (or below the 3rd percentile for age and gender dependent norms).

Abdominal distention · Frequent (79-30%)

Distention of the abdomen.

Abnormal facial shape · Frequent (79-30%)

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

Abnormal proportion of naive CD4 T cells · Frequent (79-30%)

Abnormal increase or decrease of the naive CD4+ T cell subpopulation, commonly characterized as CD45RA+, CD45RO-, or CD27+, measured as percentage of total CD4+ T cells in the blood, compared to a reference range for a given sex and age-group. These cells are sometimes also characterized as CD62L+ and CCR7+.

Abnormality of T cell physiology · Frequent (79-30%)

A functional anomaly of T cells.

Abnormality of the nervous system · Frequent (79-30%)

An abnormality of the nervous system.

Abnormality of thyroid physiology · Frequent (79-30%)

An abnormal functionality of the thyroid gland.

Anemia · Frequent (79-30%)

A reduction in erythrocytes volume or hemoglobin concentration.

Other findings in the same source

From: Orphanet

Additional reported features include Atherosclerosis (Frequent (79-30%)); Broad nasal tip (Frequent (79-30%)); Cerebral ischemia (Frequent (79-30%)); Decreased total neutrophil count (Frequent (79-30%)); Disproportionate short-trunk short stature (Frequent (79-30%)); Global developmental delay (Frequent (79-30%)); Growth delay (Frequent (79-30%)); Headache (Frequent (79-30%)); Hyperlipidemia (Frequent (79-30%)); Hypermelanotic macule (Frequent (79-30%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: MedlinePlus Genetics, National Library of Medicine

Antenatal; Infancy; Neonatal

Inheritance in the source

From: MedlinePlus Genetics, National Library of Medicine

Autosomal recessive

Frequency and the population described

From: MedlinePlus Genetics, National Library of Medicine

Reported case(s): 133.0; 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 Schimke immuno-osseous dysplasia 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 Schimke immuno-osseous dysplasia. 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.