| BackgroundSystemic amyloidosis often involves the kidneys and may lead to end-stage renal disease(ESRD).According to the different constituent precursor proteins,it can be divided into many types,with different treatment methods and prognosis.To improve patient prognosis,it will be necessary to identify different types that are essential for treatment.There are potential diagnostic flaws in conventional pathological diagnostic techniques.Laser Microdissection followed by Mass Spectrometry(LMD/MS)is a new amyloid classification method,which has not yet been widely developed in clinical practice.Objective(1)Using LMD/MS technology to identify the amyloid precursor protein of patients that cannot be diagnosed by traditional pathological diagnostic methods,so as to type diagnosis.(2)Taking the typing results of conventional pathological techniques combined with LMD/MS analysis as clues,the clinical and pathological characteristics of 321 patients with different types of amyloidosis were analyzed and compared.Methods(1)Substantial subjects:A total of 321 patients with renal amyloidosis confirmed by renal biopsy in the First Affiliated Hospital of Zhengzhou University and submitted to other hospitals on January 30,2012 and July 1,20(2)Routine pathological classification and LMD/MS analysis;kidney tissue specimens were stained with Congo red(slice thickness 6um)under light microscope and polarized light microscopy.Direct immunofluorescence detection of light chain protein κ,λ,immunohistochemical staining detection of amyloid A(AA).Observe the deposition of amyloid fibrils under an electron microscope.Collected 54 patients with paraffin-embedded pathology specimens that could not be diagnosed by conventional pathological methods during the same period.The collected specimens are sliced,deparaffinized,and stained.The laser fiber cutting system is used to obtain the amyloidosis lesion area that is positive for Congo red staining,and complete protein extraction,enzyme digestion,desalination,mass spectrometry detection,database search and data analysis.The specific protein composition of the diseased area determines the subtype of amyloidosis.(3)Collect clinical data of 321 patients with amyloid nephropathy:age,sex,course of disease(clinical symptoms to diagnosis),clinical symptoms(edema,fatigue,etc.).Biochemical indicators include hemoglobin,albumin,24-hour urine protein quantification,blood creatinine,estimated glomerular filtration rate(eGFR),complement C3,C4,and nephrotic syndrome.The diagnostic criteria are:24-hour urine protein quantification>3.5 g,blood albumin<30g/L.Renal insufficiency is defined as eGFR<60ml·min-1·(1.73 m2)-120 were selected.(4)Collect pathological data of 321 patients with amyloid nephropathy:The pathologist re-read the film under the unknown diagnosis,and semi-quantitatively scored the deposition of amyloid in various parts of the kidney,renal interstitial fibrosis,renal tubular atrophy,inflammatory cell infiltration.(5)According to the results of traditional pathological classification and mass spectrometry analysis,the patients with amyloid nephropathy are divided into groups.Among them,patients with AL/AH/AHL type amyloid nephropathy belong to the monoclonal immunoglobulin group,and the remaining subtypes are Non-monoclonal immunoglobulin group.The monoclonal immunoglobulin group was divided into AL group and AH/AHL subgroups,and the clinical and pathological characteristics of patients with amyloidosis in different groups were compared.Results(1)The diagnosis rate of LMD/MS analysis was 100%,and that of routine pathological techniques was 83.18%.The results showed that 287 cases of AL type(89.41%),23 cases of AH/AHL type(7.17%),4 cases of AA type(1.25%),2 cases of ATTR type(0.62%),2 cases of AGel type(0.62%),1 case of ALys type(0.31%),1 case of ALECT2 type(0.31%),and 1 case of ATTR+ALλ type(0.31%).(2)There was no significant difference in sex and age between the monoclonal immunoglobulin group and non-monoclonal immunoglobulin group,and the levels of urinary protein were similar(all P>0.05).The monoclonal immunoglobulin group had a lower frequency of renal damage than the non-monoclonal immunoglobulin group.pathological semi-quantitative score according to the results of monoclonal immunoglobulin group of renal interstitial amyloid(IA)deposit less,renal interstitial fibrosis with tubular atrophy(Ifib),inflammatory cells infiltration(Iinf)degree is lower,statistically significant difference(P<0.05).The comparison between the AH/AHL group and the AL group showed that patients in the AH/AHL group renal interstitial fibrosis with tubule atrophy(Ifib)is lower,the difference is statistically significant(all P<0.05).ConclusionThe clinical and pathological changes of the monoclonal immunoglobulin group were less than those of the non-monoclonal immunoglobulin type amyloidosis,and the alteration of AH/AHL type amyloidosis were more notable. |
PDF Full Text Request