The sly "M protein"

foreword

M protein is a large amount of abnormal immunoglobulin produced by the monoclonal malignant proliferation of plasma cells or B lymphocytes, and its essence is an immunoglobulin or a fragment of immunoglobul.

However, the onset of most diseases with M protein presents a chronic course, asymptomatic in the early stage, difficult to detect, and easy to be miss.

case after

History of present illness: The patient is a 69-year-old ma.

Past history: He was hospitalized in our hospital in August 2020 and was diagnosed with coronary heart disease, variant angina pectoris, cerebral arterial insufficiency, grade 3 hypertension and hypertensive retinopat.

Personal history: Born in the country of origin, no history of living abroad, never been to the epidemic area, denied the history of exposure to industrial poisons, dust and radioactive substances, and no history of travel in metallur.

After the patient was admitted to the hospital, a series of laboratory tests were performed, and the inspection items were as follows:

Significantly abnormally elevated total egg and globulin in patients with liver function (Figure 1)

Figure 1 The abnormal rise of TP and GLB triggers the re-examination rule, is it disturbed?

NSE and other tumor markers are undetectable

The blood routine showed that the patient had mild anemia (Figure 2)

Figure 2 Blood routine results of the patient

No abnormality in coagulation item results

case analysis

We first examined the specimen for abnormalities, and we found a stratification between serum and red blood cells (Figure

image 3

There was no obvious abnormality in othe.

Next, we performed electrophoresis and immunoglobulin items for the patie.

We diluted the samples with pure water and normal saline respectively (F.

Figure 4

The real reason is that when the sample is diluted with pure water, the ionic strength in the sample is reduced, which leads to cross-linking and aggregation of high immunoglobulins easily resulting in turbidi.

Now that we have found evidence of high immunoglobulins, why are there no obvious abnormalities in the results of protein electrophoresis and immunoglobulins? With confusion, then the sample we checked last time found that there was a layering phenomenon in the serum and red blood cells of the samp.

So far, all the mysteries have been solv.

Figure 5

Summary

Abnormal globulin is an indirect manifestation of liver disease and immune system damage, and even an early diagnostic indicator of some diseas.

Through this case analysis, the comprehensive patient is a middle-aged male with infection, abnormal increase in immunoglobulin, and positive IgM and light chain K in immunofixation electrophores.

Summarizing this case analysis, will it serve as a wake-up call for us in our future work, and test the normal results? There will be no probl.

Good result analysis ability and good clinical thinking ability are the necessary conditions for becoming an excellent examin.

references

[1] Su Yanjun, Hu Xiaojun, Li Gaiying, et .

Differential diagnosis of 268 cases of hyperglobulinemia [.

Chinese Journal of Modern Medicine, 2017, 19(5): 58-60

[2] Chinese Medical Doctor Association Hematologist Branch, Chinese Medical Association Hematology Branch, Chinese Medical Doctor Association Multiple Myeloma Professional Committ.

Guidelines for the diagnosis and treatment of multiple myeloma in China (revised in 2020) [.

Chinese Journal of Internal Medicine, 2020, 59(5): 341-34

[3] Shen Minna, Wu Jiong, Guo Wei, et .

Influence of M protein interference on routine biochemical detection items of serum samples [.

Laboratory Medicine, 2011, 26(11): 730-73