FROZEN (-20°C) PREFERRED OR REFRIGERATED. THERE IS LIMITED STABILITY AT ROOM (AMBIENT) TEMPERATURE AND THIS SHOULD BE AVOIDED.
0Setup
BATCHED.
Components Parameters
0 MIN (BASAL) THEN 30MIN, 60MIN, 90MIN, AND 120MIN GROWTH HORMONE AFTER 75G ORAL GLUCOSE LOAD
PRE-ANALYTIC CONSIDERATIONS
Test Ordering Instructions
FILL OUT TEST REQUEST FORM FULLY & LEGIBLY. 75GMS (OR 1.75G/KG OF BODY WEIGHT FOR CHILDREN) OF ORAL GLUCOSE. BASAL GROWTH HORMONE LEVEL 30MIN, 60MIN, 90MIN, AND 120MIN GROWTH HORMONE AFTER ORAL GLUCOSE. CONSENT FORM NEEDED. ORAL GLUCOSE PROCURED SEPARATELY.
Patient preparation
10-12 HOUR FASTING (FASTING MEANS THAT ONLY WATER AND PRESCRIBED MEDICATION IF ANY ARE PERMITTED DURING THE FASTING PERIOD); 30 MINUTES REST PRIOR TO COLLECTION. MULTI-SAMPLING WILL BE PERFORMED.
Sample type
5 SERUM SAMPLES WITH ACCURATE COLLECTION SEQUENCE ON THE SAMPLE LABELS.
Container/ preservative
SERUM SEPARATOR TUBE (SST/ GEL) OR PLAIN (RED TOP) VACUTAINER.
Sample volume
2ML OF SERUM EACH (0MIN, 30, 60, 90, 120MIN) AND COLLECTION SEQUENCE CORRECTLY LABELED ON THE 5 TUBES.
Rejection criteria
LABELING ISSUE (UNLABELED/ MISLABELED/ COLLECTION SEQUENCE NOT STATED); MISSING REQUEST FORM; MISMATCH BETWEEN REQUEST FORM & SAMPLE DETAILS; MISSING AGE/ GENDER; WRONG SAMPLE TYPE; INSUFFICIENT SAMPLE. NONFASTING BASELINE STATUS.
Other Instructions
CENTRIFUGE SST (SERUM GEL TUBES) WITHIN 1-2 HOURS OF COLLECTION. CENTRIFUGE RED TOP VACUTAINERS AND ALIQUOT SERUM WITHIN 1-2 HOURS OF COLLECTION. THE SEPARATION VIAL MUST BE LABELED WITH AT LEAST 2 PATIENT IDENTIFIERS AND THE SAMPLE TYPE.
Reference intervals
INTERPRETIVE DATA IS PROVIDED ON THE REPORT. FAILURE TO ADEQUATELY SUPPRESS IS CONSISTENT WITH AUTOMONOUS GH PRODUCTION E.G. BY ANTERIOR PITUITARY ADENOMAS OR ECTOPIC PRODUCTION.
Clinical Utility
EVALUATION OF SUSPECTED GROWTH HORMONE EXCESS E.G. GIGANTISM, ACROMEGALY.
Test Limitations/ Confounders
INCORRECT LABELING OF COLLECTION SEQUENCE WILL RESULT IN INACCURATE INTERPRETATION. UNFROZEN SAMPLES