Rejection-Biochemistry

Top 5 causes of rejection:

1. Repeated test

• • Please refer Retesting Interval.

  • Check the patient previous test results via Webpage iLab prior to blood taking procedure.

  • If retesting is indicated but the interval in between requests is shorter than the allowable limit, please consult with Integrated Laboratory MO / Pathologist during office hours OR contact oncall MO / Pathologist after office hours.

2. Test not indicated

• Special Chemistry tests require a relevant clinical information with additional investigation (imaging) in order to proceed with the test. Example given:

1. Thyroid Function Test (TSH and fT4).

   1. Neck ultrasound shows solitary/multinodular swelling.

   2. Patient on medications that can affect thyroid hormone physiology (e.g. Lithium, Amiodarone).

   3. Patient has palpitation and ECG shows new onset atrial fibrillation.

   4. Free T3 only be offered in known case of T3 thyrotoxicosis and in a newly diagnosed subclinical hyperthyroidism patient.

   5. Hyper- or hypothyroidism symptoms ALONE does NOT warrant full TFT.

2. Tumor marker.

   1. Alpha Fetoprotein (AFP) indicated as a screening tool for patient who is at high risk of developing hepatocellular carcinoma (chronic Hep B, Hep C infection).

   2. CA 15-3 only indicated in monitoring treatment in patient with breast cancer.

   3. CEA in patient with altered bowel habit and underwent colonoscopy which show polyps in the descending colon.

   4. For other tumor marker requests and indication, please refer A Quick Guide for Requesting for Serum Tumour Markers in MOH Facilities in Penang State 2021.

3. Vitamin B12 and Folate mainly indicated for:

   1. Macrocytic anaemia with unknown B12/Folate status. Please include the FBC result (Hemoglobin, MCV, MCH).

   2. Neurodegenerative/Geriatric patient.

   3. Patient with chronic malabsorption due to any cause.

   4. Patient on vitamin B12 or folate supplement/treatment.

4. Serum Protein Electrophoresis.

   1. Specialist counter-signed is compulsory.

   2. For new case, please provide a relevant clinical information, lab result and imaging findings pertaining to the CRAB symptoms (Calcium level, Renal parameters - creatinine and urea, Anemia markers - hemoglobin, and Bone indicators - skeletal survey).

5. Procalcitonin.

   1. Specialist counter-signed is compulsory.

   2. The test only offered to HQE Intensive Care Unit (ICU) patient and established Covid 19 patient. The requests received from other wards and hospitals require consultation with Integrated Laboratory MO/Pathologist during office hours OR oncall MO/Pathologist after office hours.

3. No sample received

• Prior to blood taking procedure, ensure how many volume of blood needed with number and types of blood collection tube used.

• It is often noted that request form that requested routine biochemistry test (e.g. Renal Profile, Liver Function Test, Fasting Lipid Profile) together with Fasting Blood Sugar (Glucose) will miss sending the Fluoride Oxalate tube for Glucose measurement.

• For blood glucose request, please use Fluoride Oxalate tube (grey cap).

• Test sent to referral laboratories SHOULD NOT SHARE same sample tube with tests done in-house.

4. Hemolyzed

• Difficult venepuncture and improper handling of the collected specimens increase the risk of sample hemolysis.

• Refer (*Remarks) on sample collection on factors that can contribute to sample hemolysis.

• Avoid prolonged storage of the sample in the ward or clinic. 

• Deliver specimens promptly to the laboratory following collection.

5. Blood clotted

• Clotted blood gas is not suitable for sample analysis as it can lead to damage to the cartridge or analyzer leading to downtime.

• Refer to Specimen Collection & Handling for procedure of collection and transportation of Blood Gas Specimen.