Severe congenital neutropenia

What it is, symptoms and effects

From: MedlinePlus Genetics, National Library of Medicine

Severe congenital neutropenia is a condition that increases the risk of repeated infections in affected individuals. People with this condition have an abnormally low level (deficiency) of neutrophils, a type of white blood cell that plays a role in inflammation and in fighting infection. The shortage of neutrophils, called neutropenia, is apparent at birth or soon afterward. It leads to frequent infections beginning in infancy, including infections of the sinuses, lungs, and liver. Affected individuals can also develop fevers and inflammation of the gums (gingivitis) and skin. Approximately 40 percent of affected people have decreased bone density (osteopenia) and may develop osteoporosis, a condition that makes bones progressively more brittle and likely to fracture. In people with severe congenital neutropenia, bone disorders can begin at any time from infancy through adulthood.

Approximately 20 percent of people with severe congenital neutropenia develop certain cancerous conditions of the blood, particularly myelodysplastic syndrome or leukemia during adolescence.

Some people with severe congenital neutropenia have additional health problems such as seizures, developmental delay, or heart and genital abnormalities.

ORPHANET DEFINITION A rare primary immunodeficiency, without an associated lymphocyte deficit, characterized by impaired neutrophil maturation and/or function, associated with severe infections, diverse comorbidities, and/or an increased risk of leukemic transformation.

Inheritance

From: MedlinePlus Genetics, National Library of Medicine

Autosomal recessive; Autosomal dominant; X-linked recessive

Frequency in the source

From: MedlinePlus Genetics, National Library of Medicine

Prevalence at birth: 1-9 / 1 000 000; Europe; Value and class. Point prevalence: 1-9 / 1 000 000; Europe; Value and class. Prevalence at birth: 1-9 / 100 000; Sweden; Value and class. Point prevalence: 1-9 / 1 000 000; France; Value and class.

Understanding terms used in the source

These definitions explain medical words used above. A definition is not evidence that another condition is present, and it does not predict how a symptom will develop. Ask the clinician which terms apply to the actual examination or test result.

Immunodeficiency

Failure of the immune system to protect the body adequately from infection, due to the absence or insufficiency of some component process or substance.

Osteoporosis

Osteoporosis is a systemic skeletal disease characterized by low bone density and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility. According to the WHO criteria, osteoporosis is defined as a BMD that lies 2.5 standard deviations or more below the average value for young healthy adults (a T-score below -2.5 SD).

Osteopenia

Osteopenia is a term to define bone density that is not normal but also not as low as osteoporosis. By definition from the World Health Organization osteopenia is defined by bone densitometry as a T score -1 to -2.5.

Affected

This term applies to a family member who is diagnosed with the same condition as the individual who is the primary focus of investigation (the proband).

Leukemia

A cancer of the blood and bone marrow characterized by an abnormal proliferation of leukocytes.

When it may begin

From: MedlinePlus Genetics, National Library of Medicine

Childhood

Inheritance in the source

From: MedlinePlus Genetics, National Library of Medicine

Autosomal recessive; Autosomal dominant; X-linked recessive

Frequency and the population described

From: MedlinePlus Genetics, National Library of Medicine

Prevalence at birth: 1-9 / 1 000 000; Europe; Value and class. Point prevalence: 1-9 / 1 000 000; Europe; Value and class. Prevalence at birth: 1-9 / 100 000; Sweden; Value and class. Point prevalence: 1-9 / 1 000 000; France; Value and class.

Which doctor should you see?

The suggested department for discussing Severe congenital neutropenia is Clinical Genetics, with a clinical geneticist as the relevant type of clinician. Paediatrician (children) or physician (adults), with clinical geneticist referral.

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.

• Does the exact genetic or chromosome finding explain the observed features?
• Would a genetic counsellor help the family understand the result?
• Which organ-specific assessments are appropriate for this particular diagnosis?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Severe congenital neutropenia. 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.