Test Center

My Recent Searches

  • No Recent Search.

My Tests Viewed

  • No Test Viewed.

Developmental Delay/Intellectual Disability (DD/ID)

Developmental Delay/Intellectual Disability (DD/ID)

Test Guide

Developmental Delay/Intellectual Disability (DD/ID)

  

 
Figure. Laboratory Evaluation of Developmental Delay/Intellectual
Disability (DD/ID)

    

Test Menu and Clinical Application

Individuals who present with DD/ID may benefit from the tests listed below. Some patients not yet diagnosed with DD/ID may manifest other symptoms suggestive of a genetic or metabolic disorder. These symptoms are presented herein to help identify patients who may benefit from a specific test.

Acylcarnitine, Plasma

Test Code: 14531X

Clinical Use: Diagnose organic aciduria or fatty acid disorder

Individuals Suitable for Testing: Those with cardiac arrhythmia, marked hypoglycemia, hepatomegaly, seizures, coma, muscle disease, lethargy

Amino Acid Analysis, LC/MS, CSF

Test Code: 29881

Clinical Use: Diagnose amino acid disorders in which CSF levels are elevated relative to other sample types (eg, nonketotic hyperglycinemia)

Individuals Suitable for Testing: Those with convulsions, apnea, hypotonia, poor feeding, wandering eye movements, muscle spasms, lethargy, hiccups

Amino Acid Analysis, LC/MS, Plasma
(Includes 34 analytes)

Test Code: 767X

Clinical Use: Diagnose primary aminoacidopathies or screen for secondary aminoacidopathies; monitor response to therapy

Individuals Suitable for Testing: Those with variable symptoms that may include coma, seizures, tachypnea, poor feeding, failure to thrive, vomiting, lethargy; those diagnosed with an aminoacidopathy

Amino Acid Analysis, LC/MS, Urine
(Includes creatinine)

Test Code: 36183X

Clinical Use: Diagnose primary and secondary aminoacidopathies

Individuals Suitable for Testing: Those with variable symptoms that may include coma, seizures, tachypnea, poor feeding, failure to thrive, vomiting, lethargy

Canavan Disease Mutation Analysisa

Test Code: 31650X

Clinical Use: Diagnose Canavan disease; determine carrier status

Individuals Suitable for Testing: Those with seizures, spasticity, poor visual fixation, irritability, poor feeding, poor head control, hypotonia, increased deep tendon reflexes, increased head circumference, or a family history of Canavan disease

Carnitine, LC/MS/MS

(Includes free and total carnitine and carnitine esters)

Test Code: 70107X

Clinical Use: Diagnose primary or secondary carnitine deficiency; monitor patients with carnitine deficiency

Individuals Suitable for Testing: Those with tachycardia, hepatomegaly, hypotonia, lethargy; those diagnosed with carnitine deficiency

Carnitine, LC/MS/MS and Acylcarnitine

Test Code: 15948X

Clinical Use: Diagnose organic aciduria, fatty acid disorder, primary or secondary carnitine deficiency

Individuals Suitable for Testing: Those with cardiac arrhythmia or tachycardia, hepatomegaly, seizures, hypotonia, coma, lethargy

Chromosome Analysis, Blood

Test Code: 14596

Clinical Use: Determine genetic cause of DD/ID

Individuals Suitable for Testing: Those with dysmorphic features, birth defects, growth abnormalities, behavior problems

Chromosome Analysis, Follow-up

Test Code: 10708X

Clinical Use: Diagnose a chromosomal abnormality

Individuals Suitable for Testing: Family members of individuals with a known chromosomal abnormality

FISH, Angelmana

Test Code: 14608X

Clinical Use: Diagnose Angelman syndrome

Individuals Suitable for Testing: Those with seizures, wide mouth, protruding tongue, prominent jaw, thin upper lip, absent speech, ataxic gate, paroxysmal laughter, light hair/skin pigmentation

FISH, Cri du chata

Test Code: 14614X

Clinical Use: Diagnose Cri du chat syndrome

Individuals Suitable for Testing: Those with cat-like cry, severe psychomotor dysfunction, microencephaly, round face, hypertelorism, small jaw, low-set ears, epicanthal folds, hypotonia

FISH, DiGeorge, Velocardiofacial (VCFS)a

Test Code: 14610X

Clinical Use: Diagnose DiGeorge/velocardiofacial syndrome

Individuals Suitable for Testing: Those with cardiac malformations, seizures, hypocalcemia, high susceptibility to infections, hypertelorism, cleft palate, bifid uvula, small jaw, low-set ears, speech delay, scoliosis, hernia, schizophrenia/mental health disorders

FISH, Miller-Diekera

Test Code: 14612X

Clinical Use: Diagnose Miller-Dieker syndrome

Individuals Suitable for Testing: Those with central nervous system disorders, microencephaly/lissencephaly, prominent forehead, bitemporal hollowing, small nose with upturned nares, protuberant upper lip, thin vermilion border of upper lip

FISH, Smith-Magenisa

Test Code: 14611X

Clinical Use: Diagnose Smith-Magenis syndrome

Individuals Suitable for Testing: Those with heart defect, brachycephaly, hearing loss, speech delay with hoarse/deep voice, sleep disturbance, hyperactivity, self-destructive behavior, broad face/ nasal bridge, Down syndrome-like facies

FISH, Neonatal Screena

Test Code: 36053

Clinical Use: Determine genetic cause of DD/ID (includes +13, +18, +21, X, Y)

Individuals Suitable for Testing: Those with dysmorphic features, birth defects, growth abnormalities, behavior problems

FISH, Wolf-Hirschhorna

Test Code: 14613X

Clinical Use: Diagnose or confirm the diagnosis of Wolf-Hirschhorn syndrome

Individuals Suitable for Testing: Those with cardiac septal defects, microencephaly, hypotonia, seizures, hypospadias/cryptorchidism (males), absent uterus (females), prominent glabella, short philtrum, hypertelorism, downturned corners of mouth

Gaucher Disease, DNA Mutation Analysisa

Test Code: 21503X

Clinical Use: Diagnose Gaucher disease; determine carrier status

Individuals Suitable for Testing: Those with hepatosplenomegaly, bone fractures and lesions, thrombocytopenia, or a family history of Gaucher disease

Genomic Alterations, Postnatal, ClariSure® Oligo-SNP Arrayb

Test Code: 16478

Clinical Use: Determine genetic cause of DD/ID

Individuals Suitable for Testing: Those with DD, ID, autism spectrum disorders, or multiple congenital abnormalities

Homocysteine (Nutritional and Congenital)

Test Code: 36362X

Clinical Use: Diagnose homocystinuria; monitor homocysteine levels in patients with homocystinuria

Individuals Suitable for Testing: Those with dislocated ocular lens, osteoporosis, scoliosis, thinning/lengthening of long bones, thromboembolism, psychiatric disorders, or diagnosed homocystinuria

Maple Syrup Disease (MSUD) Mutation Analysis (Ashkenazi Jewish)b

Test Code: 16067

Clinical Use: Diagnose MSUD; determine carrier status

Individuals Suitable for Testing: Those with seizures, alternating hypertonia/hypotonia, poor feeding, lethargy, failure to thrive, or a family history of MSUD

Methylmalonic Acid

Test Code: 34879

Clinical Use: Diagnose methylmalonic acidemia; monitor methylmalonic acid levels after diagnosis

Individuals Suitable for Testing: Those with respiratory distress, hepatomegaly, lethargy, failure to thrive, vomiting, hypotonia, or with diagnosed methylmalonic acidemia

Methylmalonic Acid, Urine
(Includes creatinine)

Test Code: 16508X

Clinical Use: Diagnose methylmalonic acidemia; monitor methylmalonic acid levels after diagnosis

Individuals Suitable for Testing: Those with respiratory distress, hepatomegaly, lethargy, failure to thrive, vomiting, hypotonia, or with diagnosed methylmalonic acidemia

Niemann-Pick Disease Mutation Analysisa

Test Code: 10222X

Clinical Use: Diagnose Niemann-Pick disease; determine carrier status

Individuals Suitable for Testing: Those with hepatosplenomegaly, hypotonia, muscle weakness, vomiting, constipation, and/or cherry-red corneal spot and those with a family history of Niemann-Pick disease

Organic Acids, Qualitative, Urine

Test Code: 10049X

Clinical Use: Screen for organic aciduria

Individuals Suitable for Testing: Those with variable symptoms that may include coma, liver disease, seizures, hypotonia, ataxia, failure to thrive, lethargy

Organic Acids, Quantitative, Random Urine, Full Panel

Test Code: 38067

Clinical Use: Diagnose organic aciduria

Individuals Suitable for Testing: Those with variable symptoms that may include coma, liver disease, seizures, hypotonia, ataxia, failure to thrive, lethargy

Phenylalanine

Test Code: 37356

Clinical Use: Diagnose phenylketonuria; monitor phenylalanine levels after diagnosis

Individuals Suitable for Testing: Those with seizures, poor feeding, vomiting, hyperactivity, eczema, hypopigmentation; those diagnosed with phenylketonuria

Phenylalanine and Tyrosine

Test Code: 26336

Clinical Use: Monitor response to treatment of phenylketonuria

Individuals Suitable for Testing: Those with diagnosed phenylketonuria

Prader-Willi/Angelman Syndrome, DNA Methylation Analysisa

Test Code: 11369

Clinical Use: Diagnose Prader-Willi or Angelman syndrome

Individuals Suitable for Testing: Those with severe hypotonia, poor feeding leading to gavage feeding, cryptorchidism (males), hypoplastic labia (females), strabismus, narrow bitemporal diameter, upslanting fissures, short stature, small hands and feet, obesity, hyperphagia, ataxic gate, paroxysmal laughter

Rett Syndrome Mutation Analysisb

Test Code: 15088X

Clinical Use: Diagnose Rett syndrome

Individuals Suitable for Testing: Males with unexplained neonatal encephalopathy; those with Angelman-type symptoms with normal chromosome 15q11.2-q13; those with X-linked mental retardation and a negative fragile X test

Tay-Sachs Disease Mutation Analysisa

Test Code: 21502X

Clinical Use: Diagnose Tay-Sachs disease; determine carrier status

Individuals Suitable for Testing: Those with macular pallor with cherry red spot, blindness, dementia, apathy; family members at risk of carrying a Tay-Sachs mutation

Tryptophan, LC/MS

Test Code: 959X

Clinical Use: Diagnose tryptophanuria; monitor tryptophan levels after diagnosis

Individuals Suitable for Testing: Those with photosensitive skin rash, short stature, cerebellar-like ataxia; those with diagnosed tryptophanuria

Tyrosine

Test Code: 902

Clinical Use: Diagnose tyrosinemia; monitor tyrosine levels after diagnosis

Individuals Suitable for Testing: Those with liver disease, eye symptoms of lacrimation, photophobia, redness, pain; nonpruritic, painful hyperkeratotic skin lesions; those with diagnosed tyrosinemia

XSense®, Fragile X with Reflexb,c

Test Code: 16313

Clinical Use: Diagnose fragile X syndrome; determine carrier status

Individuals Suitable for Testing: Those with dysmorphic features, birth defects, growth abnormalities, and/or behavior problems and those at risk of carrying fragile X abnormality

XSense®, Fragile X with Reflex and Chromosome Analysis, Bloodb,c

Test Code: 16326

Clinical Use: Determine genetic cause of DD/ID; diagnose fragile X syndrome; determine fragile X carrier status

Individuals Suitable for Testing: Those with dysmorphic features, birth defects, growth abnormalities, and/or behavior problems and those at risk of carrying fragile X abnormality

a This test was developed and its performance characteristics have been determined by Quest Diagnostics Nichols Institute. It has not been cleared or approved by the U.S. Food and Drug Administration. The FDA has determined that such clearance or approval is not necessary. Performance characteristics refer to the analytical performance of the test.
b This test was developed and its performance characteristics have been determined by Quest Diagnostics Nichols Institute. Performance characteristics refer to the analytical performance of the test.
c Reflex tests are performed at an additional charge and are associated with additional CPT codes. If the CGG-sizing PCR result suggests carrier status and/or an abnormal triplet-primed PCR result is detected, then Southern blot is performed

References

  1. Curry CJ, Stevenson RE, Aughton D, et al. Evaluation of mental retardation: recommendations of a
    consensus conference. Am J Med Genetics.1997;72:468-477.

  2. Shaffer LG. American College of Medical Genetics guideline on the cytogenetic evaluation of the individual with developmental delay or mental retardation. Genet Med. 2005;7:650-654.

  3. Sherman S, Pletcher BA, Driscoll DA. Fragile X syndrome: diagnostic and carrier testing. Genet Med. 2005;7:584-587.

  4. Miller DT, Adam MP, Aradhya S, et al. Consensus statement: Chromosomal microarray is a first-tier clinical diagnostic test for individuals with developmental disabilities or congenital anomalies. Am J Hum Genet. 2010;86:749-764.
     
Content reviewed 12/2011
 
top of page

* The tests listed by specialist are a select group of tests offered. For a complete list of Quest Diagnostics tests, please refer to our Directory of Services.