Developmental Delay/Intellectual Disability Diagnostic Evaluation Clinical Pathway — Primary Care

Laboratory Collection Instructions and Recommendations

The laboratory tests are recommended based on individual presentation.

Document history of special diet (such as ketogenic diet) and medication in the child’s chart and on the lab request form. These data are needed for appropriate interpretation of results.

Tests and Guidance

Plasma Amino Acids	Recommend 4 hour fasting prior to specimen draw
Metabolic Tests available at CHOP	Plasma amino acids, plasma acylcarnitine profile, urine organic acids, plasma total homocysteine, carbohydrate deficient transferrin (CDT) and N-glycan analysis
Urine Glycosaminoglycan (GAGs) Urine Oligosaccharides	Recommended laboratories Labcorp (Urine total GAGs) Quest Diagnostics^® (Urine total GAGs) Greenwood Diagnostic (CHOP send-out) Sample specifications Random urine sample, can use urine bag for young children Volume: ≥ 3 mL Container: plastic urine tube Must be sent frozen, preferably on dry ice Requisition Form for Greenwood Diagnostic Order
Urine Purine and Pyrimidine Panel	Recommended laboratory Mayo Clinic Laboratories Sample specifications Random urine sample, can use urine bag for young children Volume: ≥ 3 mL Container: plastic urine tube Must be sent frozen Requisition Form for Mayo Clinic Laboratories
Urine Creatine Disorders Panel	Recommended laboratory Mayo Clinic Laboratories Sample specifications Random urine sample, can use urine bag for young children Volume: ≥ 1 mL Container: plastic urine tube Immediately freeze the sample If possible, avoid ordering other tests to be performed on the same urine sample Requisition Form for Mayo Clinic Laboratories
Biotinidase Activity, Serum	Recommended laboratory Mayo Clinic Laboratories Sample specifications Serum sample Volume: ≥ 1 mL Container: Red-top tube Centrifuge immediately, aliquot serum into plastic vial Requisition Form for Mayo Clinic Laboratories

If you have questions about any of the clinical pathways or about the process of creating a clinical pathway, please contact us.

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The clinical pathways are based upon publicly available medical evidence and/or a consensus of medical practitioners at The Children’s Hospital of Philadelphia (“CHOP”) and are current at the time of publication. These clinical pathways are intended to be a guide for practitioners and may need to be adapted for each specific patient based on the practitioner’s professional judgment, consideration of any unique circumstances, the needs of each patient and their family, and/or the availability of various resources at the health care institution where the patient is located.

Accordingly, these clinical pathways are not intended to constitute medical advice or treatment, or to create a doctor-patient relationship between/among The Children’s Hospital of Philadelphia (“CHOP”), its physicians and the individual patients in question. CHOP does not represent or warrant that the clinical pathways are in every respect accurate or complete, or that one or more of them apply to a particular patient or medical condition. CHOP is not responsible for any errors or omissions in the clinical pathways, or for any outcomes a patient might experience where a clinician consulted one or more such pathways in connection with providing care for that patient.

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Developmental Delay/Intellectual Disability Diagnostic Evaluation Clinical Pathway — Primary Care

Laboratory Collection Instructions and Recommendations

Tests and Guidance

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Developmental Delay/Intellectual Disability — Laboratory Collection — Clinical Pathway: Primary Care

Developmental Delay/Intellectual Disability Diagnostic Evaluation Clinical Pathway — Primary Care

Laboratory Collection Instructions and Recommendations

Tests and Guidance