IgG4-related sclerosing cholangitis associated with essential thrombocythemia:A case report

BACKGROUND The complexity of immunoglobulin G4(IgG4)-related diseases and their potential connection to hematologic malignancies remains unclear.This article provided a review of the diagnosis and treatment of a patient with IgG4-related sclerosing cholangitis(SC)and essential thrombocythemia(ET),along with an analysis of relevant literature to enhance comprehension of this disease.CASE SUMMARY A 56-year-old male was admitted to two hospitals with deteriorating jaundice and pruritus prior to hospitalization.Beyond our expectations,the patient was first diagnosed with IgG4-SC and ET with the Janus kinase 2 V617F mutation.Interestingly,the administration of acetate prednisone significantly resulted in improvements in both IgG4-SC and ET.Clinicians need to pay attention to immune disorders and inflammation as they contribute to the development of various disease phenotypes.CONCLUSION When IgG4-SC is suspected without histopathological evidence,diagnostic therapy and long-term regular follow-up can lead to positive treatment outcomes.Clinicians should be mindful of the potential presence of concurrent hematologic diseases in patients with immune disorders.

Infrequent organ involvement in immunoglobulin G4-related prostate disease: A case report

BACKGROUND Immunoglobulin G4-related prostate disease(IgG4-RPD)characterized by a high count of IgG4-positive plasma cells has distinctive serological and radiological findings.Here we report a case of a patient who was successfully treated for IgG4-RPD,which manifested as frequent micturition,dysuric,and systemic lymphadenopathy.CASE SUMMARY The patient was a 33-year-old man who was referred to our hospital because of urinary tract symptoms that had persisted for 4 years.A physical examination revealed systemic lymphadenopathy and blood tests showed hyperglobulinemia with an IgG level of 18.90 g/L and an IgG4 level of 18.40 g/L.Computed tomography(CT)revealed bilateral lacrimal gland,right parotid gland and prostatic enlargement.Based on these findings,IgG4-RD was suspected,and further pathological examination and follow-up results showed expected results.Finally,the patient was diagnosed with IgG4-RPD based on clinical symptoms,pathological examination,therapeutic effects,and follow-up results.He received 50 mg oral prednisolone(the dose was gradually reduced and a low dose was used for long-term maintenance)in combination with cyclophosphamide 1.0 g via an intravenous drip for 6 mo.One year after the treatment was initiated,he was free of urinary or other complaints and his serum IgG4 level normalized.CONCLUSION In IgG4-RPD with severe urinary tract symptoms,radiological findings should be carefully examined.IgG4-RPD prognosis is good because the disease responds well to glucocorticoids.Furthermore,it is urgent for clinicians and pathologists to improve their understanding of IgG4-RPD.

Biomarkers in autoimmune pancreatitis and immunoglobulin G4-related disease

Solitary organ autoimmune disorders,formerly known as autoimmune pancreatitis(AIP),autoimmune sialadenitis,and autoimmune sclerosing cholangitis,are now considered organ-specific manifestations of systemic immunoglobulin G4-related disease(IgG4-RD).AIP and IgG4-RD are characterized by elevated serum concentration of IgG4 antibody(Ab),accumulation of IgG4-expressing plasmacytes in the affected organs,and involvement of multiple organs.It is well established that enhanced IgG4 Ab responses are a hallmark of AIP and IgG4-RD for diagnosis and monitoring disease activity.However,a significant fraction of patients with AIP and IgG4-RD who develop chronic fibroinflammatory responses have normal serum concentrations of this IgG subtype.In addition,disease flare-up is sometimes seen even in the presence of normalized serum concentrations of IgG4 Ab after successful induction of remission by prednisolone.Therefore,it is necessary to identify new biomarkers based on the understanding of the pathophysiology of AIP and IgG4-RD.Recently,we found that activation of plasmacytoid dendritic cells producing both interferon-α(IFN-α)and interleukin-33(IL-33)mediate murine AIP and human IgG4-RD.More importantly,we provided evidence that serum concentrations of IFN-αand IL-33 could be useful biomarkers for the diagnosis and monitoring of AIP and IgG4-RD activity after induction of remission in these autoimmune disorders.In this Frontier article,we have summarized and discussed biomarkers of AIP and IgG4-RD,including Igs,autoAbs,and cytokines to provide useful information not only for clinicians but also for researchers.

Immunoglobulin G4-related kidney diseases: An updated review

This review will encompass definition, pathogenesis, renal clinical manifestations and treatment of immunoglobulin G4-related diseases( IgG4-RDs). IgG4-RD is a recently recognized clinical entity that often involves multiple organs and is characterized by high levels of serum immunoglobulins G4, dense infiltration of IgG4+ cells and storiform fibrosis. Cellular immunity, particularly T-cell mediated immunity, has been implicated in the pathogenesis of IgG4-RDs. The most frequent renal manifestations of IgG4-RD are IgG4-related tubulointerstitial nephritis, membranous glomerulopathy and obstructive nephropathy secondary to urinary tract obstruction due to IgG4-related retroperitoneal fibrosis. IgG4-RD diagnosis should be based on specific histopathological findings, confirmed by tissue immunostaining, typical radiological findings and an appropriate clinical context. The first line treatment is the steroids with two warnings: Steroid resistance and relapse after discontinuation. In the case of steroid resistance, B cell depleting agents as rituximab represent the secondline treatment. In the case of relapse after discontinuation, steroid treatment may be associated with steroid sparing agents. Since the disease has been only recently identified, more prospective, long-term studies are needed to an improved understanding and a more correct and safe treatment.

Immunoglobulin G4-related autoimmune pancreatitis and sialadenitis: A case report

Immunoglobulin G4(Ig G4)-related disease is a rare systemic diseases. A 67-year-old male presented at our institution with mild upper abdominal pain and jaundice for 20 d. Laboratory results revealed high levels of Ig G4(15.4 g/L,range: 0.08-1.4 g/L). Computed tomography(CT) showed significant enlargement of the entire pancreas and a capsule-like low-density rim surrounding the whole pancreas. Positron emission tomography/CT revealed increased uneven metabolism of the entire pancreas. Both magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography showed stenosis of the distal common bile duct and proximal main pancreatic duct,and dilation of the proximal common bile duct and extra- and intra-hepatic bile ducts. He was diagnosed with Ig G4-related autoimmune pancreatitis. The patient was treated with prednisone for 14 mo. The patient responded well to prednisone but upon cessation of the corticosteroid developed enlargement of the submandibular gland. The patient's serum Ig G4 was elevated at 23.9 g/L. It is important to maintain treatment,so the patient was again treated with prednisone and had a good response. Follow-up of Ig G4-related disease is thus necessary.

Successful treatment of tubulointerstitial nephritis in immunoglobulin G4-related disease with rituximab: A case report

BACKGROUND Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated condition that consisted of disorders that share particular clinical,serologic and pathologic properties.The common presentation of disease includes tumor-like swelling of involved organs and the histopathological findings are a lymphoplasmacytic infiltrate enriched with IgG4-positive plasma cells,and a variable degree of fibrosis that has a characteristic "storiform" pattern in biopsy specimens of tumorlike masses.Major presentations of this disease,which often affects more than one organ,include autoimmune pancreatitis,salivary gland disease (sialadenitis),orbital disease and retroperitoneal fibrosis.The steroid treatment is essential for the treatment of the disease however,other immunosuppressive drugs including cyclophosphamide or rituximab could be an option in resistant cases.CASE SUMMARY Herein,we reported a 34-year-old woman whom previously had diagnosed with asthma,rheumatoid arthritis and Sj?gren’s syndrome (SS) referred our nephrology department due to acute kidney failure development at the last rheumatology visit.After kidney biopsy she has been diagnosed with IgG4-RD and tubuluointerstitial nephritis.She had been accepted resistant to steroid,mycophenolate mofetil,methotrexate and azathioprine therapies due to receiving in last two years.She refused to receive cyclophosphamide due to potential gonadotoxicity of the drug.Thus,rituximab therapy was considered.She received 1000 mg infusion,15 d apart and 6 mo later it has been administered same protocol.After one year from the last rituximab dose serum creatinine decreased from 4.4 mg/dL to 1.6 mg/dL,erythrocyte sedimentation rate decreased from 109 mm/h to 13 mm/h [reference range (RR) 0-20],and Creactive protein decreased from 55.6 mg/L to 5 mg/L (RR 0–6).All pathologic lymph nodes and masses were also disappeared.CONCLUSION Patients with IgG4-RD usually misdiagnosed with rheumatologic diseases including systemic lupus erythematous or SS and also they were screened for the presence of malignancy.Rituximab could be an important treatment option in cases with steroid resistant tubulointerstitial nephritis in IgG4-RD.

Usefulness of ultrasonography to assess the response to steroidal therapy for the rare case of type 2b immunoglobulin G4-related sclerosing cholangitis without pancreatitis:A case report

BACKGROUND A type 2b immunoglobulin G4(IgG4)-related sclerosing cholangitis(SC)without autoimmune pancreatitis is a rare condition with IgG4-SC.While the variety of the imaging modalities have tested its usefulness in diagnosing the IgG4-SC,however,the usage of ultrasonography for the assessment of the response to steroidal therapy on the changes of bile duct wall thickness have not been reported in the condition.Therefore,the information of our recent case and reported cases have been summarized.CASE SUMMARY We report the case of an 82-year-old Japanese man diagnosed with isolated IgG4-related SC based on the increase of serum IgG4,narrowing of the bile duct,its wall thickness,no complication of autoimmune pancreatitis,and IgG4 positive inflammatory cell infiltration to the wall with the fibrotic changes.The cholangiogram revealed type 2b according to the classification.Corticosteroid treatment showed a favorable effect,with the smooth decrease in serum IgG4 and the improvement of the bile duct wall thickness.CONCLUSION As isolated type 2b,IgG4-SC is rare,the images,histological findings,and clinical course of our case will be helpful for physicians to diagnose and treat the new cases appropriately.

Immunoglobulin G4-related kidney disease involving the renal pelvis and perirenal fat:A case report

BACKGROUND Immunoglobulin(Ig)G4-related disease(Ig G4-RD)is an autoimmune disease associated with chronic and progressive inflammation and fibrosis.It is difficult to differentiate Ig G4-RD involving the kidney from infectious diseases and malignancy on imaging.CASE SUMMARY We report the case of a 51-year-old Chinese man whose abdominal computed tomography scan showed diffuse bilateral enlargement of the kidneys and perirenal fat,thickening of the renal pelvic walls,and hydronephrosis of the right kidney.Relevant laboratory test results showed a serum creatinine level of 464μmol/L.The patient was diagnosed with acute renal failure and was started on intermittent hemodialysis.Further tests revealed high serum Ig G4 levels(20.8 g/L)and an enlarged right submaxillary lymph node.Biopsy and histopathological examination of the enlarged node led to the diagnosis of Ig G4-RD.After corticosteroid therapy,his serum creatinine level quickly decreased to near normal levels.CONCLUSION Ig G4-RD affecting the renal pelvis or perirenal fat is rare,with atypical imaging features.Multidisciplinary consultation is critical for accurate diagnosis and treatment of this disease.Suspected cases should undergo biopsy to avoid misdiagnosis.

Immunoglobulin G4-related disease in the sigmoid colon in patient with severe colonic fibrosis and obstruction:A case report

BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is an immune-mediated condition characterized by abundant IgG4 positive plasma cells and fibrosis in the affected tissues.It affects most parts of the body;however,there are not many reports on IgG4-RD involving the colon.CASE SUMMARY A 50-year-old man complaining of intermittent fever for more than two years was referred to our hospital.Based on various investigations before surgery,we diagnosed him with chronic perforation of the sigmoid colon caused by inflammatory change or tumor.IgG blood tests before the operation suggested IgG4-RD,and postoperative pathology confirmed this prediction.CONCLUSION We present a patient with IgG4-RD with colon involvement,which is an uncommon site.This report will expand the understanding of IgG4-RD in unknown tissues.

Isolated intrapancreatic Ig G4-related sclerosing cholangitis

Immunoglobulin G4-related sclerosing cholangitis(Ig G4-SC) is frequently associated with type 1 autoimmune pancreatitis(AIP). Association with AIP can be utilized in the diagnosis of Ig G4-SC. However, some cases of Ig G4-SC are isolated from AIP, which complicates the diagnosis. Most of the reported cases of isolated Ig G4-SC displayed hilar biliary strictures, whereas isolated Ig G4-SC with intrapancreatic biliary stricture is very rare. Recently, we have encountered 5 isolated intrapancreatic Ig G4-SC cases that were not associated with AIP, three of which were pathologically investigated after surgical operation. They all were males with a mean age of 74.2 years. The pancreas was not enlarged in any of these cases. No irregular narrowing of the main pancreatic duct was found. Bile duct wall thickening in lesions without luminal stenosis was detected by abdominal computed tomography in all five cases, by endoscopic ultrasonography in two out of four cases and by intraductal ultrasonography in all three cases. In three cases, serum Ig G4 levels were within the normal limits. The mean serum Ig G4 level measured before surgery was 202.1 mg/d L(4 cases). Isolated intrapancreatic Ig G4-SC is difficult to diagnose, especially if the Ig G4 level remains normal. Thus, this type of Ig G4-SC should be suspected in addition to cholangiocarcinoma and pancreatic cancer if stenosis of intrapancreatic bile duct is present.

First case of IgG4-related sclerosing cholangitis associated with autoimmune hemolytic anemia

To our knowledge,patients with immunoglobulin G4-related sclerosing cholangitis(IgG4-SC)associated with autoimmune hemolytic anemia(AIHA)have not been reported previously.Many patients with IgG4-SC have autoimmune pancreatitis(AIP)and respond to steroid treatment.However,isolated cases of IgG4-SC are difficult to diagnose.We describe our experience with a patient who had IgG4-SC without AIP in whom the presence of AIHA led to diagnosis.The patient was a73-year-old man who was being treated for dementia.Liver dysfunction was diagnosed on blood tests at another hospital.Imaging studies suggested the presence of carcinoma of the hepatic hilus and primary sclerosing cholangitis,but a rapidly progressing anemia developed simultaneously.After the diagnosis of AIHA,steroid treatment was begun,and the biliary stricture improved.IgG4-SC without AIP was thus diagnosed.

IgG4-Related Disease:A Retrospective Chinese Study of Features and Treatment Response of 98 Patients Including 4 Rare Cases

The features and treatment of 98 Chinese patients with immunoglobulin G4 (IgG4)-related disease (IgG4-RD) referred to a single tertiary referring centre were reviewed. Patientsdiagnosed with IgG4-RD according to the comprehensive diagnostic criteria (CDC) were includedin the retrospective study from May 2012 to March 2019. We collcted data on clinical, laboratory,imaging, histological features and treatment. Totally, 98 patients with IgG4-RD were enrolled.The common clinical manifestations included abdominal pain, salivary gland swelling andlymphadenopathy. 51% of the patients had multiple organs involvement. Lymph nodes, pancreasand salivary glands were most commonly involved. Four rare sites including ulna, cerebellum,scalp, and mammary gland were found. The serum IgG4 level was increased by 85.7%. The serumIgG4 level was positively correlated with the number of involved organs, IgG and IgG4/IgG. LowC3 and C4 levels were observed in 37.5% and 12.2% patients respectively, and all patients withkidney involvement had hypocomplementemia. A total of 54 patients underwent tissue biopsies,and 55.6%, 31.5% and 11.1% cases were diagnosed as definite, probable and possible IgG4-RD,respectively. Eighty-eight patients received glucocorticoids (GCs) therapy. Five patients underwentradical surgery to remove the lesion. 73% of them presented a complete or partial remission. IgG4-RD is a systemic fibroinflammatory disease with involvement of multiple organs throughout thebody including some rare sites. Most IgG4-RD patients had increased serum IgG4 levels andpatients with kidney involvement showed bypocomplementermia. GCs therapy is effective. Moreresearch is needed to provide a more reliable basis for the diagnosis and treatment of patients.

Immunosuppressant treatment for IgG4-related sclerosing cholangitis: A case report

BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is a multi-system fibroinflammatory disorder that can involve any organ,including the salivary glands,pancreas,and biliary tree.Treatment of immunoglobulin G4-related sclerosing cholangitis(IgG4-SC)is similar to that for IgG4-RD,but progression is irreversible in some cases.We present a case of IgG4-SC in which an immuno-suppressant induced marked clinical and radiologic improvement.CASE SUMMARY A 63-year-old male presented with a prominent itching sensation and wholebody jaundice.He showed obstructive-pattern jaundice,an elevated IgG4 level,and infiltration of a large number of IgG4-positive cells in the ampulla of Vater.The imaging findings of intrahepatic duct(IHD)and common bile duct dilation,an elevated serum IgG4 level,and characteristic histological findings led to diagnosis of IgG4-SC that compatible with the 2019 ACR/EULAR classification criteria.We planned to treat the patient with high-dose glucocorticoid(GC),followed by cyclophosphamide pulse therapy.After treatment with high-dose GC and an immunosuppressant,imaging studies showed that IHD dilatation had completely resolved.CONCLUSION Prompt diagnosis and appropriate treatment of IgG4-SC are important.Because there is a risk of relapse of IgG4-SC,the GC dose should be gradually reduced,and a maintenance immunosuppressant should be given.

Clinical and pathological differences between serum immunoglobulin G4-positive and -negative type 1 autoimmune pancreatitis

AIM: To identify clinical and pathological differences between serum immunoglobulin G4 (IgG4)-positive (SIP) and IgG4-negative (SIN) type 1 autoimmune pancreatitis (AIP) in South Korea. METHODS: AIP was diagnosed by the international consensus diagnostic criteria. The medical records and pathology were retrospectively reviewed and IgG4-positive cells were counted in a high power field (HPF). Type I AIP was defined as a high serum level of IgG4or histological finding. SIN type 1 AIP was defined as a histological evidence of type 1 AIP and a normal serum IgG4 level. The clinical and pathological findings were compared between the two groups. The analysis was performed using Student's t test, Fischer's exact test and Mann-Whitney's U test. A P value of < 0.05 was considered statistically significant. As repeated com- parison was made, P values of less than 5% (P < 0.05) were considered significant. RESULTS: Twenty five patients with definite type 1 AIP (19 histologically and six serologically diagnosed cases) were enrolled. The mean tissue IgG4 concentrations were significantly higher in SIP than SIN group (40 cells per HPF vs 18 cells per HPF, P = 0.02). Among eight SIN patients, the tissue IgG4 concentrations were less than 15 cells per HPF in most of cases, except one. The sensitivity of serum IgG4 was 68% (17 SIP and eight SIN AIP). Other organ involvement was more frequent- ly associated with SIP than SIN AIP (59% vs 26%, P = 0.016). However, the relapse rate and diffuse swelling of the pancreas were not associated with serum IgG4 level. The concentrations of IgG4-positive cells per HPF were higher in SIP than SIN AIP (40 vs 18, P = 0.02). CONCLUSION: The sensitivity of serum IgG4 was 68% in type 1 AIP. High serum IgG4 level was associated with other organ involvement and tissue IgG4 concentration but did not affect the relapse rate in type 1 AIP.

Autoimmune thrombocytopenia in response to splenectomy in cirrhotic patients with accompanying hepatitis C

AIM： To estimate the contribution of autoimmune thrombocytopenia to hepatitis C virus-related liver cirrhosis （type C cirrhosis）, we evaluated the influence of splenectomy upon platelet-associated immunoglobulin G （PAIgG） levels and platelet numbers. METHODS： PAIgG titers and immune markers were determined in 24 type C cirrhotic patients with an intact spleen, 17 type C cirrhotic patients submitted to splenectomy, and 21 non-C cirrhosis with an intact spleen. RESULTS： Thrombocytopenia （PLT〈15×10^4/μL） in type C cirrhosis was diagnosed in all patients with an intact spleen, 8 patients submitted to splenectomy, and in 19 non-C cirrhosis with intact spleen. Elevated titers of PAIgG at more than 25.0 ng/107cells were detected in all cirrhotic patients except for one splenectomized patient. PAIgG titers （ng/10^7cells） were significantly higher in the type C cirrhosis with an intact spleen （247.9 ± 197.0） compared with the splenectomized patients （125.6±87.8） or non-C cirrhosis （152.4± 127.4）. PAIgG titers were negatively correlated with platelet counts in type C cirrhotic patients with an intact spleen. In comparison with the type C cirrhosis with an intact spleen, the splenectomized patients had a reduced CD4/CD8 ratio and serum neopterin levels. The spleen index （cm^2） was negatively correlated with platelet counts in the non-C cirrhosis, but not in the type C cirrhosis. CONCLUSION： Our data indicate that the autoimmune mechanism plays an important role in thrombocytosis complicated by HCV-positive cirrhosis. In addition, splenectomy may impair T cells function through, at least in part, a reduction of CD4/CD8 ratio, consequently suppressing PAIgG production.

Understanding autoimmune pancreatitis: Clinical features, management challenges, and association with malignancies

In this editorial we comment on the article by Jaber et al.Autoimmune pancreatitis(AIP)represents a distinct form of pancreatitis,categorized into AIP-1 and AIP-2,characterized by obstructive jaundice,lymphoplasmacytic infiltrate,and fibrosis.AIP-1,associated with elevated immunoglobulin G4(IgG4)levels,exhibits higher relapse rates,affecting older males,while AIP-2 is less common and linked to inflammatory bowel disease.AIP is considered a manifestation of IgG4-related systemic disease,sharing characteristic histological findings.Steroids are the primary treatment,with emerging biomarkers like interferon alpha and inter-leukin-33.AIP poses an increased risk of various malignancies,and the assoc-iation with pancreatic cancer is debated.Surgery is reserved for severe cases,necessitating careful evaluation due to diagnostic challenges.AIP patients may have concurrent PanINs but display favorable long-term outcomes compared to pancreatic cancer patients.Thorough diagnostic assessment,including biopsy and steroid response,is crucial for informed surgical decisions in AIP.

Humoral and cellular immunogenecity of DNA vaccine based on hepatitis B core gene in rhesus monkeys

INTRODUCTIONHepatitis B virus (HBV) is the most commonetiologic agent for infectious liver diseases. It isestimated that there are more than 250 millionchronic HBV carriersin the world today and thereis a significant association among persistentinfection, liver cirrhosis and hepatocellularcarcinoma[1-3].

EFFECTS OF ACUPUNCTURE ON THE IMMUNOLOGICAL FUNCTIONS IN HEPATITIS B VIRUS CARRIERS

A contrast study on the effects of manual acupuncture and electroacupuncture wasconducted in 60 cases of chronic hepatitis B carriers.The results demonstrated that theimmunological functions,both cellular and humoral,were markedly regulated asevidenced by the negative turnover rates of HBsAg,HBeAg,anti-HBc and HBcAg,as wellas the positive turnover rate of anti-HBe.

累及颞骨的IgG4相关性疾病1例

IgG4相关性疾病（immunoglobulin G4-relateddisease,IgG4-RD）又称为IgG4相关硬化性疾病,是一种免疫介导的可累及多器官的系统性疾病。其特点主要表现为病变组织中硬化性假瘤的形成,淋巴浆细胞的弥漫性浸润,席纹样纤维化或闭塞性静脉炎。IgG4-RD可侵犯全身各部位,包括头颈部区域,但耳部受累的病例十分少见。

Perifollicular granulomas with Ig G4 plasmacytosis:A case report and review of literature

Perifollicular granuloma is a unique histologic feature and whether it is associated with immunoglobulin G4(IgG 4)-related disease is controversial. We report a case of a 38-year-old man who presented with worsening left eye pain, proptosis, tearing, gritty sensation, blurred vision and multiple lymphadenopathy. An axillary lymph node resection showed reactive follicular and interfollicular lymph node hyperplasia, and increased eosinophils and plasma cells(at least 80% of Ig G+ plasma cells were positive for IgG 4). A distinct feature was the presence of multifocal, perifollicular histiocytic granulomas, which formed a wreath around the entire follicles. The human herpes virus 8 was not detected by immunohistochemistry. In addition, an extensive panel of special stains, immunohistochemistry, and flow cytometry was negative for lymphoma, fungal, or mycobacterial infection. The findings were suggestive of IgG 4-related sclerosing disease-associated lymphadenopathy. Further laboratory testing showed a significant increase of serum immunoglobulin E(> 23000 IU/mL) and slight increase of total Ig G, but normal serum Ig G4. Even though perifollicular granuloma is a nonspecific histopathologic feature and can be seen in other diseases, such as nodular lymphocyte predominant Hodgkin lymphoma, Ig G4-related lymphadenopathy should be listed in the differential diagnoses of benign reactive lymph nodes, especially when perifollicular granuloma and plasmacytosis coexist.