Intravenous blood glucose <0.3, peripheral blood glucose 5.0, where did the blood sugar go?

Blood sugar is an important source of energy for the normal operation of the body.

Recently, an extremely low blood sugar result has attracted the attention of laboratory teachers.

Blood sugar is an important source of energy for the normal operation of the body.

Recently, an extremely low blood sugar result has attracted the attention of laboratory teachers.

Patient, male, 37 years old, fatigue, abdominal distension for more than 2 months

【History of present illness】

In the past two months, the patient had no obvious inducements for conscious fatigue, abdominal distension, discomfort in the left upper abdomen, gastric discomfort after eating, no obvious oiliness, nausea, vomiting, abdominal pain, and diarrhea

【Auxiliary Inspection】

WBC: 130*109/L, promyelocytic 0.

Meso-myelocytic cells 0.

Rod-shaped nucleus granulocytes are 0.

Clinical diagnosis : chronic myeloid leukemia

The clinician stated that the patient's blood sugar could not be so low because:

1.

2.

At this time, the teacher in the department has a question, why is the GLU test result so low? Is it caused by equipment, reagents, etc.

3.

• Re-collect blood samples
  .
  

Re-collect blood samples
.

• It is suspected whether it is related to the time when the specimen is placed
  .
  

It is suspected whether it is related to the time when the specimen is placed
.

(2) Serum samples and whole blood samples collected at the same time were placed for 1 hour for testing.
It was found that the blood glucose results of the whole blood samples dropped greatly, reaching 1/3 of the original results, while the blood glucose results of the serum samples did not change significantly
.

It is confirmed that the whole blood sample will decrease with the increase of the storage time, and the blood sugar result will decrease
.

It has been reported in the literature that for normal specimens, the blood glucose concentration in the blood specimens was measured after 2 hours at room temperature and 3 hours, and the drop rates were 6.
57% and 10.
18%
.
Therefore, in order to prevent the decomposition of blood sugar, those specimens that cannot be tested immediately should be centrifuged and stored as soon as possible
.
At the same time, many documents record that patients with leukemia, especially "chronic myeloid leukemia", often have pseudo-hypoglycemia when the white blood cells are elevated
.
The main reason is that the proliferation of granulocytes and platelets in leukemia patients is extremely active, the metabolism is vigorous, and the consumption of glucose is increased
.
At room temperature, normal blood glucose decreases by 20-25% per hour
.
[2]  

In addition to leukemia, are there other conditions that can cause a false reduction in blood sugar? With this question in mind, let's discuss several cases of false hypoglycemia today
.

It is not uncommon for patients with leukemia, especially "chronic myeloid leukemia", to suffer from hypoglycemia.
The main reason is explained in the above article
.
In addition, patients with other types of leukemia and tumor patients also have hypoglycemia.
The main reasons are that the tumor consumes too much glucose, produces too little glucose, glycogen synthesis or decomposition and release defects, malnutrition, and abnormal fat mobilization
.
At present, most scholars believe that tumors mainly release insulin-like substances and cause hypoglycemia
.
Hypoglycemia can inhibit endogenous self-insulin secretion, and eventually form hypoglycemia and hypoinsulinemia
.
Insulin-like substances released by tumor cells are similar in biological activity to endogenous self-insulin, and both can lower blood sugar
.
[3]

2 The storage method of blood samples can also cause false hypoglycemia

Polycythemia is characterized by significantly exceeding normal levels of the number of red blood cells, hemoglobin and total blood.
Polycythemia vera is a myeloproliferative disease dominated by clonal erythrocytosis
.

The decrease in blood glucose concentration is due to the fact that red blood cells can survive for a certain period of time after being isolated.
They can obtain energy through glycolysis.
Red blood cells use 100% anaerobic glycolysis of glucose to obtain energy.
Therefore, the longer the specimen is placed, the more obvious the decrease in blood sugar will be
.
[5]

Cyanotic congenital heart disease is caused by the existence of abnormal passages between the left and right hearts, combined with right ventricular outflow tract obstruction (pulmonary artery stenosis) or severe pulmonary hypertension, which causes the right heart pressure to increase and exceed the left heart, and the blood flows from the left to the left.
The abnormal passage between the right heart shunts from right to left, and the patient develops persistent cyanosis.
At this time, the pulmonary blood flow is reduced, and the common tetralogy of Fallot and the downward movement of the tricuspid valve are common
.

Cyanotic congenital heart disease due to long-term hypoxemia, under the action of erythropoietin, it will stimulate the bone marrow to produce more red blood cells, which will produce polycythemia.
It uses anaerobic glycolysis of glucose to obtain energy and consume blood.
The glucose in it will reduce blood sugar during the red blood cell stocking time after blood sampling
.
   

Fasting blood sugar is, we often say POCT blood glucose, refers to clinical testing in the next patient, and detecting the general fingers at the end of whole blood as a detection sample, comprising a small artery, the capillary vessels mixed blood and venules, and may also contain interstitial At the same time, rapid blood glucose is easily affected by many factors such as hematocrit, capillary oxygen partial pressure and excessive squeezing
.
Therefore, the test results of peripheral blood and venous blood are different.
The blood glucose level measured by the automatic laboratory biochemical analyzer using serum as the sample is 11.
2% higher than that of peripheral blood and about 6.
9% higher than that of venous whole blood.
This may be When the serum is separated from the whole blood, red blood cells are aggregated and squeezed to cause some red blood cells to rupture, and glucose is released into the serum, causing the glucose concentration to be higher than that of whole blood
.
[6] 

1.
Standardize the pre-treatment process
.

2.
View the response curve of the specimen result
.

3.
Combine the results of other test items
.

4.
Establish a complete re-inspection process
.

It must be analyzed from the clinical patient's own reasons
.
include:

1.
Establish a good way of communication with clinicians to clarify whether the clinical symptoms are consistent with the test results
.

2.
According to the conditions of different patients, adopt corresponding detection strategies
.

Only in this way can we review, issue a qualified inspection report, and be responsible for the results and the patients
.

【Reference Materials】