FADD-related immunodeficiency
Learn about FADD-related immunodeficiency, its reported features, relevant specialists, and questions to discuss at a medical consultation.
The sources compiled here do not cover: diagnosis, treatment, prevention, prognosis. Ask the treating doctor about these.
What it is
From: Orphanet
FADD-related immunodeficiency is a rare genetic immunological disease reported in a single consanguineous Pakistani family with several affected members presenting with severe bacterial and viral infections, recurrent hepatopathy (portal inflammation, fibrosis), and recurrent, stereotypical febrile episodes, sometimes lasting several days, with encephalopathy and difficult-to-control seizures. Variable cardiac malformations were also reported. Although there were autoimmune lymphoproliferative syndrome (ALPS)-like biological features, clinical ALPS was not present. A homozygous missense mutation in the FADD gene (11q13.3) was found in the family and the disease is thought to follow an autosomal recessive pattern of inheritance.
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.
- Decreased liver function · Obligate (100%)
- Reduced ability of the liver to perform its functions.
- Encephalopathy · Obligate (100%)
- Encephalopathy is a term that means brain disease, damage, or malfunction. In general, encephalopathy is manifested by an altered mental state.
- Seizure · Obligate (100%)
- A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
- Cerebral atrophy · Frequent (79-30%)
- Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum.
- Hepatic fibrosis · Frequent (79-30%)
- The presence of excessive fibrous connective tissue in the liver. Fibrosis is a reparative or reactive process.
- Autoimmune antibody positivity · Occasional (29-5%)
- The presence of an antibody in the blood circulation that is directed against the organism's own cells or tissues.
- Pulmonary artery atresia · Occasional (29-5%)
- A congenital anomaly with a narrowing or complete absence of the opening between the right ventricle and the pulmonary artery.
- Ventricular septal defect · Occasional (29-5%)
- A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum.
When it may begin
From: Orphanet
Infancy; Neonatal
Inheritance in the source
From: Orphanet
Autosomal recessive
Frequency and the population described
From: Orphanet
Reported case(s): 4.0; 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 FADD-related immunodeficiency is Allergy and Immunology, with a allergist / clinical immunologist 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.
- Does the history suggest an allergy, an immune problem or another explanation?
- How would any proposed allergy or immune test change care?
- Is an individual emergency plan needed, and who should understand it?
Treatment discussions and follow-up
The material gathered for this draft does not provide a complete condition-specific treatment pathway for FADD-related immunodeficiency. 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.
Allergy and Immunology is not listed separately on The Doctor Index; the nearest speciality is internal medicine. Every profile shows the doctor’s registration and what has been checked.
All allergy and immunology conditions →
Sources
- Orphanet — FADD-related immunodeficiency — Orphadata Science, CC BY 4.0
- Human Phenotype Ontology Consortium — terminology definitions — HPO licence; definitions reproduced without alteration
- MedlinePlus Genetics — inheritance patterns — Public-domain Genetics education
- Government of India — Emergency Response Support System — Official reference for India emergency number
Source: MedlinePlus, National Library of Medicine. Orphadata Science: Free access data from Orphanet. © INSERM 1999; July 2026 data, CC BY 4.0. This product uses the Human Phenotype Ontology (hp/releases/2026-09-01). Only sources listed for this article apply. Source material has been selected and arranged; HPO definitions are reproduced without alteration. No source organisation endorses this compilation. Köhler S et al. The Human Phenotype Ontology project: linking molecular biology and disease through phenotype data. Nucleic Acids Research 2014;42(D1):D966–D974. doi:10.1093/nar/gkt1026.
General information, not advice about your situation. Errors can be reported through the corrections process. Reference TDI-C-0874.