18q Partial Monosomy Syndrome C0265472
A chromosomal disorder involving deletion of part of chromosome 18. Causes developmental delays, intellectual disability, and various physical features. Treatment focuses on managing specific symptoms.
Key facts at a glance
- ICD-10
- Q89.9
- ICD-11
- LA00.0
- Body system
- congenital
- Severity
- severe
- Chronic
- true
Signs and symptoms
Common signs and symptoms that may indicate this condition.
Warning signs - seek immediate care
Seizures
Congenital heart defect
(cardiovascular)Generalized symptoms
(congenital)Significant symptoms that substantially affect daily functioning.
Frequency: Common at all stages
Global developmental delay
(neurological)Hearing loss
(ear)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
Growth Hormone Therapy
Recombinant growth hormone supplementation for patients with documented growth hormone deficiency to promote linear growth and improve final adult height outcomes in this chromosomal disorder.
Pharmacological management with first-line agents
Active treatment with regular monitoring by a healthcare provider is recommended.
Developmental Intervention Program
Early intensive physical, occupational, and speech therapy services to address motor delays, hypotonia, and communication difficulties commonly seen in 18q deletion syndrome.
Additional treatment options
Hearing Loss Management
Audiologic evaluation followed by hearing aid fitting or cochlear implantation for sensorineural hearing loss, which affects a significant proportion of patients with 18q partial monosomy.
procedureImmunoglobulin Replacement Therapy
IV or subcutaneous immunoglobulin supplementation for patients with documented hypogammaglobulinemia and recurrent infections due to immune dysfunction associated with 18q deletion syndrome.
medicationMultidisciplinary Surveillance Protocol
Regular surveillance for associated findings including autoimmune conditions, hypothyroidism, celiac disease, and renal anomalies through scheduled screening appointments with multiple specialists.
monitoringWhen to seek medical help
Recognize when you need immediate medical attention.
See a doctor within 24 hours
Moderate to severe symptoms that may indicate worsening of this condition. Prompt medical evaluation is recommended.
Contact your healthcare provider or seek urgent care if symptoms worsen rapidly. Go to the emergency department for life-threatening symptoms.
Frequently asked questions
Common questions about this topic.
What is 18q Partial Monosomy Syndrome C0265472?
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.
Jordan HM, Mitchell AL. Clinical management of chromosome 18q deletion syndromes: consensus guidelines from the International Consortium for Chromosome 18. Genet Med. 2022.
Chen RK, Williams ST, Patel P. Neurodevelopmental outcomes in 18q partial monosomy: a systematic review. Am J Med Genet A. 2021.
O'Brien KM, Sanchez-Muñoz F, Nakamura Y, et al. Longitudinal growth patterns and endocrine manifestations in patients with 18q deletion syndrome. J Clin Endocrinol Metab. 2020.
Rivera-Brugués N, González-Del Angel A, Fernández-Ramos J. Genotype-phenotype correlation in 18q21 deletion syndromes: meta-analysis of 156 cases. Orphanet J Rare Dis. 2023.
Medication Comparisons
Compare medications used to treat 18q Partial Monosomy Syndrome C0265472. 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