Kleefstra Syndrome 2 C4540395
A rare genetic condition affecting multiple body systems, causing intellectual disability and distinctive facial features. Treatment involves managing specific symptoms with a team of specialists.
Key facts at a glance
- ICD-10
- G40.909
- ICD-11
- 8A00.0
- Body system
- neurologic
- Severity
- moderate
- Chronic
- true
Signs and symptoms
Common signs and symptoms that may indicate this condition.
Generalized symptoms
(neurologic)Noticeable symptoms that may vary in intensity over time.
Frequency: Common at all stages
Global developmental delay
(neurologic)Speech and language impairment
(neurologic)Behavioral abnormalities
(neurologic)Microcephaly
(neurologic)Diagnosis and tests
How this condition is diagnosed and what test results mean.
Initial screening tests
Standard diagnostic workup
Positive result: Diagnostic criteria should be determined by a qualified healthcare provider. [Content pending medical review.]
Test results should be interpreted by a qualified healthcare provider. [Content pending medical review.]
Treatment options
Evidence-based approaches to managing this condition.
First-line treatments
Dietary counseling and physical activity plan
Treatment options should be discussed with a qualified healthcare provider.
Early intervention physical therapy
Structured physical therapy program focusing on motor skill development, muscle tone normalization, and improving coordination and balance. Therapy is typically provided 2-3 times weekly with regular reassessment of developmental progress.
Behavioral and developmental interventions
Applied behavior analysis (ABA) and developmental psychology support addressing communication, social skills, and behavioral challenges commonly associated with Kleefstra syndrome. Interventions are tailored to individual cognitive level.
Additional treatment options
Seizure management
Anticonvulsant medications may be prescribed if seizure activity is present, with selection based on seizure type and individual tolerability. Regular EEG monitoring helps guide treatment adjustments.
medicationSpeech and communication therapy
Speech-language pathology focusing on language development, alternative communication systems, and feeding difficulties. Augmentative and alternative communication (AAC) devices may be introduced when appropriate.
complementaryMultidisciplinary monitoring
Regular comprehensive monitoring including cardiac evaluation, renal ultrasound, and endocrine assessment to screen for associated anomalies. Coordinated care across specialties ensures early detection of complications.
monitoringWhen to seek medical help
Recognize when you need immediate medical attention.
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Frequently asked questions
Common questions about this topic.
What is Kleefstra Syndrome 2 C4540395?
Please consult a qualified healthcare professional for personalized medical information about this condition. [Content pending medical review.]
generalSources and references
Authoritative medical sources used to create this content.
Kleefstra T, Kramer JM. Kleefstra syndrome: clinical and molecular update. Hum Genet. 2022;141(3-4):285-300.
Willemsen MH, Rujendra R, Lee B, et al. Consensus guidelines for diagnosis and management of Kleefstra syndrome spectrum disorders. Genet Med. 2021;23(7):1200-1213.
Cogné B, Eggermann S, Marlair C, et al. Molecular characterization and clinical phenotype of KMT5C-related Kleefstra syndrome 2. Mol Genet Genomic Med. 2020;8(11):e1478.
Faundes V, Newman WG, Clayton-Smith J. Phenotypic spectrum and genetics of EHMT1-related and KMT5C-related neurodevelopmental disorders: a systematic review. Orphanet J Rare Dis. 2023;18(1):45.
Medication Comparisons
Compare medications used to treat Kleefstra Syndrome 2 C4540395. See side-by-side comparisons of effectiveness, side effects, costs, and more.
View Medication ComparisonsThis information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 20, 2026. · Read our editorial policy