Insights into the immunological description of cryoglobulins with regard to detection and characterization in Slovenian rheumatological patients.

The detection of cryoglobulins (CG) used to diagnose cryoglobulinemic vasculitis requires strict adherence to protocol, with emphasis on the preanalytical part. Our main objectives were to introduce a more sensitive and specific protocol for the detection of CG and to characterize CG in Slovenian patients diagnosed with cryoglobulinemic vasculitis, other vasculitides, connective tissue diseases or non-rheumatic diseases examined at the Department of Rheumatology (University Medical Centre Ljubljana). Samples were routinely analyzed for the presence of CG with the protocol using the Folin-Ciocalteu reagent. In the newly introduced protocol, the type of CG was determined by immunofixation on visually observed positive samples and the concentration of CG in the cryoprecipitate and rheumatoid factor (RF) activity were measured by nephelometry. RF, C3c and C4 were measured in patients` serum and a decision tree analysis was performed using all results. The agreement between negative and positive results between the two protocols was 86%. Of the 258 patient samples tested, we found 56 patients (21.7%) with positive CG (37.5% - type II, 62.5% - type III). The RF activity was observed in 21.4% of CG positive subjects. The median concentration of type II CG was significantly higher than that of type III CG (67.4 mg/L vs. 45.0 mg/L, p = 0.037). Patients with type II had lower C4 concentrations and higher RF compared to patients with type III CG. In the decision tree, C4 was the strongest predictor of cryoglobulinemia in patients. With the newly implemented protocol, we were able to improve the detection and quantification of CG in the samples of our rheumatology patients and report the results to adequately support clinicians.

Lupus nephritis with cryoglobulinemic glomerulonephritis features: a diagnostic conundrum.

In this clinical case, we report an atypical and unique presentation of systemic lupus erythematosus (SLE) in a 39-year-old female with nephrotic syndrome. The patient exhibited class IV plus V lupus nephritis and extensive immune complex deposition within the intracapillary and arteriolar regions suggestive of cryoglobulinemic glomerulonephritis, despite no detectable circulating cryoglobulins. Electron microscopy revealed cryoglobulin-like deposit distribution in all glomerular examined compartments, namely subendothelial, intramembranous, subepithelial, and mesangial, apparently extending from the capillary hyaline thrombi. The case highlights the possibility of severe renal injury in SLE without circulating cryoglobulins and the diverse kidney manifestations associated with the disease. However, the impact on patient outcome was minimal, as classical treatment (id est National Institute of Health regimen) remained effective.

Recent updates in the diagnosis and management of cryoglobulinemic vasculitis.

INTRODUCTION: Cryoglobulinemic vasculitis (CV), also known as mixed cryoglobulinemic syndrome (MCS), is a systemic vasculitis that affects small blood vessels. It exhibits a wide range of clinical manifestations, making its treatment a continuing challenge for physicians. AREAS COVERED: We conducted a comprehensive review to evaluate the current status of diagnosis, management, and treatment of mixed cryoglobulinemia (MC). The accurate clinical and serological evaluation plays a vital role in diagnosing MC, identifying potential comorbidities, and monitoring its main manifestations and complications. Treatment strategies should be individualized based on the underlying etiopathogenesis, the severity of organ involvement, and the associated underlying disease. At present, the two mainstays of CV treatment are direct antiviral agents (for HCV-related CV) and B-cell-targeted therapy. EXPERT OPINION: MC remains one of the few autoimmune diseases where the etiology is known, at least for the majority of patients. Its pathogenetic mechanism offers a unique opportunity to investigate the interplay between infections and the immune system. Moving forward, the primary challenge will continue to lie in the treatment of resistant or refractory cases of CV, particularly those associated with autoimmune diseases, or cases classified as 'essential' CV.

Serological and Molecular Characterization of Hepatitis C Virus-Related Cryoglobulinemic Vasculitis in Patients without Cryoprecipitate.

Prolonged B cells stimulation due to the Hepatitis C virus (HCV) can result in autoimmunity, stigmatized by rising levels of cryoglobulins (CGs), the rheumatoid factor (RF), and free light chains (FLC) of immunoglobulins (Ig) associated with a range of symptoms, from their absence to severe cryoglobulinemic vasculitis and lymphoma. Here, we aimed to identify an immunological signature for the earliest stages of vasculitis when cryoprecipitate is still not detectable. We firstly analyzed the IgG subclasses, FLC, and RF in 120 HCV-RNA-positive patients divided into four groups according to the type of cryoprecipitate and symptoms: 30 asymptomatic without cryoprecipitate (No Cryo), 30 with vasculitis symptoms but without CGs that we supposed were circulating but still not detectable (Circulating), 30 type II and 30 type III mixed cryoglobulinemia (Cryo II and Cryo III, respectively). Our results revealed that patients with supposed circulating CGs displayed a pattern of serological parameters that closely resembled Cryo II and Cryo III, with a stronger similarity to Cryo II. Accordingly, we analyzed the groups of Circulating and Cryo II for their immunoglobulin heavy chain (IgH) and T-cell receptor (TCR) gene rearrangements, finding a similar mixed distribution of monoclonal, oligoclonal, and polyclonal responses compared to a control group of ten HCV-RNA-negative patients recovered from infection, who displayed a 100% polyclonal response. Our results strengthened the hypothesis that circulating CGs are the origin of symptoms in HCV-RNA-positive patients without cryoprecipitate and demonstrated that an analysis of clonal IGH and TCR rearrangements is the best option for the early diagnosis of extrahepatic complications.

A Rare Manifestation of Hepatitis A Associated Cryoglobulinemia.

Cryoglobulins can precipitate in the blood when exposed to lower temperatures. These abnormal immunoglobulins are more commonly affiliated with Hepatitis C infection but there have been cases reported with Hepatitis A association for which we present this case. The patient was treated with steroids which did show gradual improvement of symptoms but, ultimately, the patient developed renal failure and required temporary hemodialysis. Care should be taken to assess patients with cryoglobulins for other viral serologies besides Hepatitis C.

Non-hepatitis-associated mixed cryoglobulinemia with polyclonal plasma cells disease and alcoholic cirrhosis: A rare case report.

Mixed cryoglobulinemia refers to the serum presence of a variety of cryoglobulins, which are defined as immunoglobulins that precipitate at temperatures of < 37°C. The most common cause of mixed cryoglobulinemia is hepatitis C virus (HCV), while other infections, including hepatitis B virus (HBV) and HIV infections, and lymphoproliferative and autoimmune disorders have also been associated with the disease. We reported a rare case of type II-III mixed cryoglobulinemia caused by alcoholic cirrhosis. We need to increase the awareness of and facilitate the early identification of mixed cryoglobulinemia in our clinical study when encountering a patient with liver cirrhosis combined with renal impairment so that treatment can begin early to improve the success rate of therapy and reduce the fatality rate in a potentially life-saving therapy.

Monoclonal Gammopathy of Thrombotic Significance.

The current review provides an overview of the thrombotic risk observed in patients with MG who do not otherwise require treatment. We discuss clinical and biomarker studies that highlight the heterogenous hemostatic profile observed in these patients and how knowledge has evolved over the past 20 years. Biomarker studies suggest shared biologic features between multiple myeloma and monoclonal gammopathy of undetermined significance (MGUS), which involves both hypercoagulability and platelet activation. Hemostatic abnormalities identified in MGUS patients cannot be translated into clinical practice as they lack correlation to clinical events. The prothrombotic phenotype of MGUS patients has not been ascertained yet, but novel data on coagulation markers are promising. We also review rare conditions associated with the thrombogenic properties of the monoclonal protein that predispose to arterial, venous or microthrombotic events and demonstrate that the M-protein can be linked to clinically significant thrombotic events. Cryoglobulinemia, cryofibrinogenemia, cryo-crystaloglobulinemia and MG-related antiphospholipid syndrome are reviewed. We propose the new umbrella term "monoclonal gammopathy of thrombotic significance" (MGTS) to refer to significant, recurrent thrombotic events in patients with MGUS that provide a rationale for targeting the underlying plasma cell clone. Identifying MGUS patients at high risk for thrombotic events is currently a challenge.

Cutaneous Pedal Manifestations in Patient With Hepatitis C Virus-Associated Cryoglobulinemia: Case Report and Review of Literature.

Cryoglobulinemia is an uncommon blood dyscrasia that can manifest itself in the lower extremity. Due to the insidious nature of this disease, dermatological symptoms and ulcerations can easily be mistaken for more common entities. The authors present an overview of cryoglobulinemia and a case report of a patient with lower extremity manifestations of this disorder. This can provide specific guidance on the steps necessary to accurately establish the diagnosis of cryoglobulinemia or rule it out and pursue other etiologies causing lower extremity ulceration.

Management of mixed cryoglobulinemia with rituximab: evidence and consensus-based recommendations from the Italian Study Group of Cryoglobulinemia (GISC).

Cryoglobulinemic vasculitis (CV) or mixed cryoglobulinemic syndrome (MCS) is a systemic small-vessel vasculitis characterized by the proliferation of B-cell clones producing pathogenic immune complexes, called cryoglobulins. It is often secondary to hepatitis C virus (HCV), autoimmune diseases, and hematological malignancies. CV usually has a mild benign clinical course, but severe organ damage and life-threatening manifestations can occur. Recently, evidence in favor of rituximab (RTX), an anti-CD 20 monoclonal antibody, is emerging in CV: nevertheless, questions upon the safety of this therapeutic approach, especially in HCV patients, are still being issued and universally accepted recommendations that can help physicians in MCS treatment are lacking. A Consensus Committee provided a prioritized list of research questions to perform a systematic literature review (SLR). A search was made in Medline, Embase, and Cochrane library, updated to August 2021. Of 1227 article abstracts evaluated, 27 studies were included in the SLR, of which one SLR, 4 RCTs, and 22 observational studies. Seventeen recommendations for the management of mixed cryoglobulinemia with rituximab from the Italian Study Group of Cryoglobulinemia (GISC) were developed to give a valuable tool to the physician approaching RTX treatment in CV.

Cryocrystalglobulinemia Leading to Multi-Organ Failure in Chronic Lymphocytic Leukemia Achieving Complete Renal Recovery.

Cryocrystalglobulinemia (CCG) is a rare and fatal subset of type I cryoglobulinemia that is classically associated with an underlying monoclonal gammopathy. Cryocrystalglobulins are created when immunoglobulins self-assemble into extracellular crystal arrays, which often leads to severe systemic hypoperfusion and occlusive vasculopathy that culminates in multi-organ failure. Most commonly, the resultant ischemia manifests as cutaneous lesions and renal insufficiency, which can progress to fulminant kidney failure requiring renal replacement therapy. CCG is commonly associated with lymphoproliferative disorders and is most frequently reported in the literature in context of plasma cell dyscrasias with minimal cases describing CCG secondary to other types of lymphoid neoplasms, especially those that attain complete organ recovery. We report a unique case of a patient who presented with multi-organ failure, including cryoglobulinemic glomerulonephritis (CryoGN) consistent with monoclonal gammopathy of renal significance (MGRS), who was found to have type I IgG kappa CCG due to chronic lymphocytic leukemia (CLL). With the assistance of plasmapheresis, hemodialysis, and clone-directed therapy, the patient achieved complete renal recovery. We highlight this uncommon entity to emphasize the clinical importance of early diagnosis and timely treatment given CCG's significant morbidity and mortality.

Serum cystatin C is an early renal dysfunction biomarker in patients with hepatitis C virus.

Background: Hepatitis C virus (HCV) may induce extrahepatic manifestations as acute or chronic renal dysfunction. The aim was to evaluate the diagnostic role of some biomarkers as cystatin C, cryoglobulins, rheumatoid factor (RF), and complement C3 for extrahepatic renal affection in newly diagnosed patients with HCV infection. Methods: Blood and urine were collected from randomized individuals screened for new HCV infection (n=400). The studied populations were divided into 3 groups: control group I: thirty healthy individuals not suffering from either liver or kidney diseases, group IIa: thirty HCV patients who have positive HCV antibody test but showed negative PCR test, and group IIb: thirty HCV patients who showed positive results for both HCV antibody and PCR tests. Results: In HCV group IIb, levels of serum total bilirubin, AST and ALT, and urine albumin/creatinine ratio were increased whereas serum albumin and creatinine clearance were decreased versus other groups. However, the levels of blood urea nitrogen and serum creatinine were still within the normal range in all groups. In HCV group IIb, cystatin C, cryoglobulins, and RF levels were increased; meanwhile, serum creatinine/cystatin C ratio and complement 3 levels were decreased compared to the other groups. HCV-infected patients significantly had higher serum cystatin C (>1.24 mg/L, P<0.001) and lower creatinine/cystatin C ratio (<70.1µMol/mg, P=0.002), and cystatin C was significantly correlated with liver and kidney parameters. Conclusion: High serum cystatin C and low creatinine/cystatin C ratio may be early indicators of mild renal dysfunction with normal serum levels of creatinine in HCV-infected individuals.

FORECASTING THE DEVELOPMENT OF PURULENT-INFLAMMATORY POSTOPERATIVE COMPLICATIONS IN PATIENTS WITH OBSTRUCTIVE BOWEL OBSTRUCTION.

OBJECTIVE: The aim: The purpose of the study is to improve the results of treatment of patients with acute intestinal obstruction of tumor origin by developing individualized surgical tactics considering the level of cryoglobulins. PATIENTS AND METHODS: Materials and methods: 96 patients with ileus of tumor origin were studied. The mean age of patients was 54.7 ± 5.9 years. 30 patients were diagnosed with colorectal cancer, 35 patients - with sigmoid cancer, 13 patients - with cecum and ascending colon, 11 patients - with transverse colon cancer, and 7 patients with descending colon cancer. Isolation of cryoglobulins from blood serum was performed by the method of A. E. Kalovidoris with modifications. The content of Ig A, Ig M, Ig G, total Ig E in the serum was investigated using enzyme-linked immunosorbent assay systems "Granum-Ukraine", the content of allergen-specific Ig E was investigated using enzyme-linked immunosorbent assay systems produced by "Microgen". RESULTS: Results: As a result of treatment of 96 patients, it was found that the level of development of postoperative purulent complications was significantly influenced by the level of cryoglobulinemia and the volume of surgery (CMU, p <0.05). It was found that in patients with decompensated intestinal obstruction, the initial concentration of cryoglobulins was 16.4% higher than in the group with compensated intestinal obstruction (CMU, p <0,05). CONCLUSION: Conclusions: Determination of cryoglobulinemia on admission of patients with acute obstructive ileus of tumor origin is a simple and effective method for predicting the development of purulent-inflammatory complications in the postoperative period and can influence the choice of treatment tactics.

Analysis of cryoproteins with a focus on cryofibrinogen: a study on 103 patients.

OBJECTIVES: Cryofibrinogen (CF) is an abnormal protein in plasma that precipitates at 4 °C and dissolves at 37 °C. Whilst serum cryoglobulins (CGs) analysis is common practice, CF investigation is rarely performed. This study aims to describe the testing methodology developed at our laboratory, potential pitfalls for all analytical phases, the distribution among hospital wards and clinical conditions underlying test requests and clinical conditions in which to order CF analysis is useful. METHODS: Retrospective analysis of laboratory samples received between January 2019 and June 2021 with CF testing requests. RESULTS: A complete protocol for CF pre-analytical, analytical and post-analytical phases are supplied. Most test requests were received from the rheumatology department for systemic sclerosis or liver transplant screening. Among the 103 in-patients included, CF+ was confirmed in 68 patients (66%). Of observed CF+ patients (n=68) most cases were CGs- (n=44, 67%). Isolated CF was found in 43% of the cases. Among CF- patients (n=35; 34%) only 2 patients had positive CGs (CGs+). Among rheumatology patients (n=66), isolated CF+ was observed in 45% (n=30/66), whilst among patients with systemic sclerosis with CF+ (n=19), isolated CF+ was detected in 79% (n=15/19). CONCLUSIONS: Described analytical procedures may be used for the creation of harmonized recommendations and indications for CF analysis. Isolated CF positivity among hospitalized patients, predominantly rheumatology and systemic sclerosis patients, appears higher than rates previously reported in literature. We propose CF test recommendations should be included in investigation protocols for diseases where cryofibrinogenemia may occur.

Vasculitis crioglobulinémica por hiperviscosidad y formación de criogel como debut de mieloma múltiple. Caso clínico / Cryoglobulinemic vasculitis due to hyperviscosity and cryogel formation as the onset of multiple myeloma. Report of one case

Multiple Myeloma (MM) is characterized by a clonal expansion of plasma cells in the bone marrow. These cells typically produce a monoclonal immunoglobulin, and its symptoms arise either from plasma cell infiltration in several organs, or secondary to the presence of a monoclonal protein peak. Symptoms can be summarized by the acronym CRAB (hypercalcemia, renal failure, anemia and bone lesions). Sometimes, in the setting of a protein secreting monoclonal gammopathy, formation of cryoglobulins develops. Cryoglobulins are plasma proteins that precipitate at low temperatures, forming a cold - induced precipitate at small vessels, causing a wide range of clinical manifestations. We report a female consulting for ulcers lasting 2 months in the left foot associated with purpuric lesions in both lower limbs. Protein electrophoresis showed a monoclonal peak in the gamma region. Bone marrow aspirate showed 27% of plasma cells with kappa chain restriction by cytometry. The presence of cryoglobulins was confirmed. The patient was treated with dexamethasone and bortezomib, with a progressive healing of lower limb lesions and disappearance of cryoglobulins. She was discharged in good conditions.

[Cryoglobulinemic vasculitis]. / Kryoglobulinämische Vaskulitis.

Cryoglobulinemic vasculitis (CV) is a rare immune complex disease of small vessels (capillaries, venules or arterioles) with detection of cryoglobulins (CG). These are serum proteins that precipitate at temperatures below the normal body temperature. The laboratory diagnostics are logistically challenging because the temperature of the blood sample must be maintained continuously at 37 °C until arrival in the laboratory to prevent early precipitation of the proteins with adsorption to corpuscular blood components. Cryoglobulins can be divided into three classes (types I-III), with each class associated with specific underlying diseases and symptom complexes. Cryoglobulinemia can be caused by hematological, virological or autoimmune diseases and mixed forms also occur. The most common cause to date is a hepatitis C infection. Treatment of the underlying disease is obligatory, with antiviral treatment of hepatitis C offering the rare possibility of causal treatment. Depending on the severity of cryoglobulinemia, immunosuppressive therapy is indicated to prevent permanent damage caused by the inflammation.

Practical Details for the Detection and Interpretation of Cryoglobulins.

BACKGROUND: Cryoglobulins are immunoglobulins that precipitate at low temperature. Strict preanalytical and analytical conditions are critical for the detection of cryoglobulins. CONTENT: This review will focus on practical recommendations for detection and characterization of cryoglobulins and the technical problems that may be encountered. A laboratory report format is proposed for presentation of these results that includes the parameters necessary for an optimal interpretation by clinicians. The first step of detection of cryoglobulins can be performed in any laboratory that has a 37 °C incubator and temperature-controlled centrifuge. The second step is the characterization of cryoglobulins, and this often must be performed in more specialized laboratories. Characterization includes immunoglobulin typing, for the classification of cryoglobulins and potential underlying disease(s); quantification of immunoglobulins and rheumatoid factor in the cryoprecipitate to define the pathogenicity; and quantification of serum complement, which is useful for diagnosis. SUMMARY: These practical recommendations will be useful for the accurate detection of cryoglobulins, an essential step for the diagnosis of cryoglobulinemic vasculitis, a rare but severe clinical manifestation of cryoglobulins.

A Case of Mixed Type II Cryoglobulinemic Vasculitis Associated With Marginal Zone B-cell Lymphoma.

Our patient is a male in his 40s with a past medical history of sickle cell trait, factor V Leiden mutation, marginal zone B-cell lymphoma, gastric mucosa-associated lymphoid tissue (MALT) lymphoma, and sarcoidosis who presented with the complaint of hemoptysis, dyspnea, abdominal pain, arthralgias, peripheral edema of the lower extremities with petechial rash, and oliguria. Investigations revealed acute kidney injury and bilateral transudative pleural effusion. Serology was positive for elevated rheumatoid factor, low complement components, and cryoglobulins. Renal biopsy showed membranoproliferative cryoglobulinemic glomerulonephritis with deposition of monoclonal IgM and IgG3 with kappa light chain and C3 component. The patient was diagnosed with mixed type II cryoglobulinemic vasculitis in the setting of untreated marginal B-cell lymphoma. He had a complex clinical course, requiring multiple intubations, hemodialysis, and treatment with intravenous immunoglobulin, plasmapheresis, steroids, and chemotherapy, to which he initially responded. During treatment, he developed cardiomyopathy associated with congestive heart failure and passed away due to cardiac arrest. We present a rare case of mixed type II cryoglobulinemic vasculitis secondary to untreated marginal zone B-cell lymphoma in a hepatitis C virus (HCV) negative patient, which has not been reported before.

Crioglobulinemia: una entidad heterogénea / Cryoglobulinemia: a heterogeneous entity

La crioglobulinemia se define como la presencia de inmunoglobulinas en el suero que se precipitan reversiblemente a bajas temperaturas. Se la clasifica en tipos I, II y III, según las características de las inmunoglobulinas. La primera suele asociarse a enfermedades linfoprolife-rativas y las de tipos II y III, denominadas crioglobulinemias mixtas, a infección por el virus de la hepatitis C, seguida de las enfermedades autoinmunes. Las manifestaciones clínicas se relacionan con obstrucción intravascular en el caso de la crioglobulinemia de tipo I, mientras que las de tipos II y III se manifiestan con vasculitis por depósito de inmunocomplejos. El compromiso cutáneo es el hallazgo principal, seguido del articular, el neurológico y el renal. Se presentan 3 casos de crioglobulinemia que, por los datos de laboratorio y las enfermedades asociadas, difieren de la descripción clásica publicada en los textos.

Cryoglobulinemia is defined as the presence of immunoglobulins in serum that reversibly precipitate at low temperatures. It is classified into types I, II and III on the basis of immunoglobulin characteristics. Type I is associated with lymphoproliferative disorders, type II and III known as mixed cryoglobulinemia, are associated with hepatitis C virus infection and autoimmune diseases. Clinical manifestations are related with occlusion of small and medium blood vessels common in type I cryoglobulinemia while immune-mediated vasculitis is frequent in mixed cryoglobulinemia. Cutaneous damage is the main manifestation, followed by joint, peripheral nerves and renal involvement. We present three cases of cryoglobulinemia that differ from the literature due to their laboratory findings and associated diseases.

Unusual Morphological and Automated Hematology Analyzer Features in 3 Cases of B-cell Malignancy-associated Type I Cryoglobulinemic Vasculitis.

Type I cryoglobulins are monoclonal immunoglobulins produced due to underlying hematological malignancy. Cryoglobulins spontaneously precipitate from serum and plasma at low temperatures and become soluble again on rewarming to 37 °C. Processing of blood at temperature lower than 37 °C in the laboratory may cause precipitation of cryoglobulins resulting in interferences in the automated cell counter analysis. We report three patients with cryoglobulinemic vasculitis wherein each case had different morphology of cryoglobulin precipitates on peripheral blood film, like needle shaped bluish-gray crystals, amorphous weakly basophilic extracellular deposits extraneously indenting red blood cells and basophilic neutrophilic inclusions respectively. The effect of cryoglobulins on two technologically different automated cell counters based on principles of impedance, Volume-Conductivity-Scatter (VCS) and fluorescence flow cytometry was assessed. This case series provides interesting insight into the varying morphological features of cryoglobulins on May-Grunwald-Giemsa stained blood films and interference caused by cryoglobulins in different automated cell counter analysis resulting in pseudo-leucocytosis, pseudo-thrombocytosis, abnormal histograms and scatterplots. Identification of these hematologic abnormalities and artifacts induced by cryoglobulins is necessary since it may be the first clue leading to the timely diagnosis of cryoglobulinemia and hence the underlying hematological malignancy, as in our cases.