Cryocrystalglobulinemia-An Uncommon Cutaneous Presentation of Multiple Myeloma and Novel Finding of Transepidermal Elimination of Crystals.

ABSTRACT: Cryocrystalglobulinemia (CCG) is a rare subset of type 1 cryoglobulinemia that is classically associated with an underlying paraproteinemia. The cryocrystalglobulins are characterized by extracellular crystals, which are eosinophilic, periodic acid-Schiff positive, and exhibit nonbirefringence under polarized light. This archetypal appearance renders CCG readily diagnosable histologically. Unlike in mixed cryoglobulinemias (types II and III cryoglobulinemia) where there is complement-mediated inflammation amounting to vasculitis, the deposition of crystallized paraproteins within vessels in CCG result in an occlusive vasculopathy and culminate in severe systemic involvement. Aside from cutaneous lesions, the resultant ischemic hypoperfusion manifest frequently with fulminant acute kidney failure, polyarthralgia, peripheral neuropathy, or gastrointestinal ulceration, conferring a poor prognosis. We present an unusual case of a patient diagnosed with immunoglobulin G kappa multiple myeloma that first presented with cutaneous necrosis as a result of CCG and did not have any renal impairment or fatal outcome. We highlight this uncommon entity to underscore the clinical importance of early diagnosis to avoid significant morbidity and mortality. In addition, we also discuss a novel feature of transepidermal elimination of crystalline precipitates demonstrated on his skin biopsy.

Cryoglobulinemic glomerulonephritis: clinical presentation and histological features, diagnostic pitfalls and controversies in the management. State of the art and the experience on a large monocentric cohort treated with B cell depletion therapy.

Cryoglobulinemia is defined by the presence of immunoglobulins having the following characteristics: forming a gel when temperature is <37 °C, precipitate in a reversible manner in the serum, and redissolve after rewarming. The presence of both polyclonal IgG and monoclonal IgM (type II), or of polyclonal IgG and polyclonal IgM (type III) identifies the mixed cryoglobulinemia (MC). The identification of the Hepatitis C virus (HCV) infection in most of the cases previously defined as "essential" represented a cornerstone in the understanding the pathogenesis of this condition. The picture of MC comprehends heterogeneous clinical presentations: from arthralgias, mild palpable purpura, fatigue to severe vasculitis features with skin necrotic pattern, peripheral neuropathy and, less commonly, lungs, central nervous system, gastrointestinal tract, and heart involvement. The kidney represents the most common organ presentation, and the presence of glomerulonephritis is a key element when considering prognosis. We discuss the clinical presentation and histological features, diagnostic pitfalls, and controversies in the management of patients with cryoglobulinemic glomerulonephritis, with a special focus on reporting our experience in treating patients with B cell depletion therapy.

Rituximab plus belimumab in non-infectious refractory cryoglobulinemia vasculitis: A pilot study.

OBJECTIVE: To report the efficacy of rituximab plus belimumab in patients with refractory cryoglobulinemia vasculitis (CV). METHODS: Belimumab was administered intravenously at a dose of 10 mg/kg on days 0, 14, 28 and then every month in association with rituximab in 4 patients with refractory CV. Demographic, clinical and laboratory characteristics, treatment modalities and outcomes were recorded. RESULTS: All patients had type II IgM Kappa cryoglobulinemia, which was associated with primary Sjögren syndrome (n = 1), hepatitis C virus infection (n = 1), and essential (n = 2). Main manifestations of CV included purpura (n = 4), arthralgia and peripheral neuropathy (n = 3), and glomerulonephritis and skin ulcers (n = 1). In all cases, CV was refractory and/or relapse following rituximab. Intravenous belimumab infusion along with rituximab resulted in rapid clinical response in the four patients. Osteitis and recurrent urinary tract infections occurred in two patients. CONCLUSION: Belimumab along with rituximab showed promising results in refractory patients with CV.

Monoclonal glomerulopathy with features of cryoglobulinemic glomerulopathy in murine multiple myeloma model.

In vivo and animal models of monoclonal light chain-associated renal diseases are limited. The Vk*MYC transgenic model with multiple myeloma in 50-70 weeks old mice with renal involvement has been reported before, but detailed renal pathologic changes have not been well documented. This study fully investigated pathologic changes in the kidneys of Vk*MYC transgenic model using light microscopy, immunofluorescence stains for kappa and lambda light chains, and electron microscopy. Compared to the kidneys of wild-type mice, the kidneys of transgenic mice showed either mesangial segmental expansion, some with associated hypercellularity, and/or thrombotic obstruction of glomerular capillaries. The glomeruli revealed stronger lambda staining than kappa light chain staining. Six out of 12 kidneys from transgenic mice showed abundant electron-dense deposits when examined ultrastructurally. The deposits were located in glomerular capillary lumina in three cases. Large luminal and subendothelial deposits were characterized by randomly disposed microtubular structures measuring up to 16 nm in diameter, with overall features most consistent with cryoglobulins. In summary, about 50% of kidneys from the Vk*MYC mice with myeloma had features most consistent with monoclonal cryoglobulinemic glomerulopathy.

Clinicopathological study of mixed cryoglobulinemic glomerulonephritis secondary to hepatitis B virus infection.

BACKGROUND: Cryoglobulinemic glomerulonephritis (CryoGn) caused by hepatitis B virus (HBV) infection was rarely reported. Our study aimed to investigate the clinical features, renal pathology findings, and prognosis in patients with HBV related CryoGn. METHODS: This was a retrospective study including seven Chinese patients with HBV related CryoGn in a tertiary referral hospital from April 2016 to March 2019. The clinical and pathological data were collected and analyzed. RESULTS: Age at renal biopsy was 47 ± 12 years, with female/male ratio 3/4. Urine protein was 5.6 (3.0, 6.6) g/d and five cases presented with nephrotic syndrome. The baseline eGFR was 23.5 (20.2, 46.3) ml/min per 1.73m2. The extrarenal manifestations included purpura (n = 6), arthralgia (n = 1), peripheral neuropathy (n = 1), and cardiomyopathy (n = 1). Six cases had type II cryoglobulinemia with IgMκ, the other one had type III. The median cryocrit was 4.0 (1.0, 15.0) %. Renal pathologic findings on light microscopy: endocapillary proliferative glomerulonephritis (Gn) (n = 3), membranoproliferative Gn (n = 3), and mesangial proliferative Gn (n = 1). On immunofluorescence microscopy, the predominant type of immunoglobulin deposits was IgM (n = 5). HBsAg and HBcAg deposits were found in one case. Ultrastructural studies showed granular subendothelial and mesangial electron-dense deposits in all patients and microtubules in one case. All patients received antiviral medications. They were given corticosteroid alone (n = 2) or combined with cyclophosphamide (n = 4) or mycophenolate mofetil (n = 1). Two patients received plasmapheresis. The median follow-up time was 18 (6, 37) months. Four patients got remission, two patients died of pneumonia, and one progressed to end-stage renal disease (ESRD). At endpoint of follow-up, 24hUP was 2.1 (0.8-5.2) g/d, and eGFR was 55.3 (20.7, 111.8) ml/min per 1.73m2. The median cryocrit decreased to 1.0 (0, 5.75) %. CONCLUSIONS: The etiology of mixed CryoGn should be screened for HBV infection. Endocapillary proliferative Gn and membranoproliferative Gn were the common pathologic patterns. Diagnosis and treatment in early stage benefit patients' renal outcomes. Immunosuppressive therapy should be considered for severe renal disease, based on efficient antiviral therapy.

Clinical characteristics and treatment outcome of type I cryoglobulinemia in Chinese patients: a single-center study of 45 patients.

To explore the clinical characteristics and outcomes in Chinese patients with type I cryoglobulinemia (CG), we retrospectively analyzed the clinical data, management, and outcomes of 45 patients diagnosed with type I CG in our hospital from January 2015 to March 2019. In our study, all type I CGs were secondary to hematologic diseases, and monoclonal gammopathy of unknown significance was the most common primary disease, accounting for 48.9% (n = 22). Additionally, B cell non-Hodgkin lymphoma, Waldenström's macroglobulinemia, and multiple myeloma accounted for 24.4% (n = 11), 20.0% (n = 9), and 6.7% (n = 3), respectively. In patients with type I CG, skin damage was the most common symptom, presenting in 57.8% of the patients, followed by peripheral neuropathy (22.2%) and renal involvement (15.6%). Treatment was initiated in 29 patients (64.4%), and the most common choice was a rituximab-based regimen in 13 patients (44.8%), followed by bortezomib-based regimen in 11 patients (37.9%). Clinical symptoms were significantly improved after treatment, and the clinical remission rate was 86.2%, including 34.5% of complete clinical remission, while the laboratory response rate was 88.9%, including 33.3% of complete response and 55.6% of partial response. The expected 1-year overall survival was 97.8%. In conclusion, for patients with multisystemic involvement, such as skin damage, kidney damage, or peripheral neuropathy, the diagnosis of type I CG should be considered, and the underlying disease needs to be explored. Symptoms and primary diseases should be taken into consideration before choosing initial management.

Membranoproliferative Glomerulonephritis and Mixed Cryoglobulinemia as a Form of Presentation of Visceral Leishmaniasis.

BACKGROUND Visceral leishmaniasis (VL) is an endemic systemic disease in the Mediterranean countries, including Spain. This vector-borne infection can present with several clinical presentations, from asymptomatic to severe forms. Renal impairment is frequently described in VL but is usually mild and related to interstitial nephritis, being that glomerular involvement is rarely found. CASE REPORT We describe a case of a 69-year-old Spanish male presenting with subacute renal failure due to membranoproliferative glomerulonephritis and mixed cryoglobulinemia accompanied by other autoimmune features (hypocomplementemia, antinuclear and antiDNA antibodies). No hepatosplenomegaly was found with abdominal ultrasound. Hepatotropic viruses and human immunodeficiency virus serological markers were negatives. We initially suspect the presence of an autoimmune disease and the patient was treated with steroids without improvement. After an extensive study including renal and bone marrow biopsy, a correct diagnosis of visceral leishmaniasis was made, and treatment with liposomal amphotericin B was initiated, achieving renal function recovery and normalization of immunological manifestations. CONCLUSIONS Renal involvement can be an important feature of VL and it might be associated with increased morbidity and mortality. The association between mixed cryoglobulinemia and renal involvement in VL have rarely been described. VL is frequently associated with diverse autoimmune manifestations and it can be initially misdiagnosed, which could lead to fatal consequences. The role of the immune system in the formation of cryoglobulins are discussed. In our case, an autoimmune disease was initially suspected, and starting treatment with steroids pulses was initiated. However, the presence of mixed cryoglobulinemia in this patient who was hepatitis C serological marker negative and who had poor renal function recovery after immunosuppressive treatment made us suspect other pathologies. The presence of cryoglobulinemia with renal disease in endemic areas of Leishmania should make us exclude this infection before starting immunosuppressive treatment.

Rheumatoid factor-producing CD21low anergic clonal B-cells in essential mixed cryoglobulinaemia: a model for autoantigen-driven pathogenesis of infectious and non-infectious cryoglobulinaemias.

OBJECTIVES: Essential mixed cryoglobulinaemia (EMC) is a disorder of B-cells producing rheumatoid factor (RF), and is clinically and immunologically similar to mixed cryoglobulinaemia (MC) related to hepatitis C virus (HCV-MC). We report here the first comprehensive analysis of B-cell clonality, phenotype and function in EMC. METHODS: The study population included 16 patients with EMC and 24 patients with HCV-MC. Molecular analysis was done for the detection of circulating clonal B cells and for B cell receptor sequencing. B-cell phenotype, proliferative response, apoptosis and ERK signaling were analysed by flow cytometry. RESULTS: Molecular analysis of immunoglobulin genes rearrangements revealed circulating B-cell clones in about half of patients, on average of smaller size than those found in HCV-MC patients. Sequence analysis showed usage of the same stereotyped RF-encoding B-cell receptors frequently expressed in HCV-MC and in primary Sjögren's syndrome. B-cells with low expression of CD21 (CD21low) and unusual homing and inhibitory receptors were increased in EMC and in HCV-MC, but at a significantly lower extent in the former. The CD21low B-cells of EMC and HCV-MC patients shared functional features of exhaustion and anergy, namely reduced proliferation upon ligation of Toll-like receptor 9, high constitutive expression of phosphorylated ERK, and proneness to spontaneous apoptosis. CONCLUSIONS: Our findings suggest a common pathogenetic mechanism in EMC, HCV-MC and primary Sjögren's syndrome, consisting of autoantigen-driven clonal expansion and exhaustion of selected RF-producing B-cells. The more massive clonal expansion in HCV-MC may be due to co-stimulatory signals provided by the virus.

Retiform purpura: Workup and therapeutic considerations in select conditions.

In this article we focus on updates in select etiologies of retiform purpura. These causes of retiform purpura, in addition to bacterial or fungal sepsis, disseminated intravascular coagulation, purpura fulminans, and catastrophic antiphospholipid syndrome, are important diagnoses with potential for morbidity and mortality. Important aspects in the pathophysiology, patient demographics and risk factors, updates in the diagnostic workup, histopathology, and treatment of these specific conditions are discussed.

Cryoglobulinemic vasculitis and glomerulonephritis: concerns in clinical practice.

OBJECTIVE: Cryoglobulinemia often causes systemic vasculitis, thereby damaging to skin and internal organs including kidneys, even life-threatening. This review aimed to introduce the advances in understanding, detection, and treatment of this disease in recent years, with a particular concern to clinical practice. DATA SOURCES: All the data in this review were from the English or Chinese literature in the PubMed and China National Knowledge Infrastructure databases as of March 2019. STUDY SELECTION: This review selected important original articles, meaningful reviews, and some reports on cryoglobulinemia published in recent years and in history, as well as the guidelines for treatment of underlying diseases which lead to cryoglobulinemia. RESULTS: Diagnosis of cryoglobulinemia relies on serum cryoglobulin test, in which to ensure that the blood sample temperature is not less than 37°C in the entire pre-analysis phase is the key to avoid false negative results. Cryoglobulinemic vasculitis (Cryo Vas), including cryoglobulinemic glomerulonephritis (Cryo GN), usually occurs in types II and III mixed cryoglobulinemia, and can also be seen in type I cryoglobulinemia caused by monoclonal IgG3 or IgG1. Skin purpura, positive serum rheumatoid factor, and decreased serum levels of C4 and C3 are important clues for prompting types II and III Cryo Vas. Renal biopsy is an important means for diagnosis of Cryo GN, while membranous proliferative GN is the most common pathological type of Cryo GN. In recent years, great advances have been made in the treatment of Cryo Vas and its underlying diseases, and this review has briefly introduced these advances. CONCLUSIONS: Laboratory examinations of serum cryoglobulins urgently need standardization. The recent advances in the diagnosis and treatment of Cryo Vas and GN need to be popularized among the clinicians in related disciplines.

Clinical practice: hepatitis C virus infection, cryoglobulinemia and cryoglobulinemic vasculitis.

Cryoglobulins are circulating immunoglobulins that reversibly precipitate at temperatures below 37 °C. Type-II cryoglobulins consist of monoclonal IgM/polyclonal IgG immune complexes (ICs), whereas in type-III cryoglobulins both IgM and IgG are polyclonal. The clinical condition resulting from the presence of cryoglobulins in the blood is called mixed cryoglobulinemia (MC), which can be asymptomatic or manifest as cryoglobulinemic vasculitis (CV). Type-I cryoglobulins, consisting of a single monoclonal isotype, are detected in patients with lymphoproliferative disorders. It is now established that > 90% of MCs are associated with HCV infection. Clinically, the spectrum of symptoms may range in severity from occasional purpuric eruptions to life-threatening features. In addition to the development of liver cirrhosis and hepatocellular carcinoma, the possible progression of HCV-positive CV patients to B-cell non-Hodgkin lymphoma (B-NHL) has been reported. The pathogenetic role played by HCV infection in the onset of B-NHL is suggested by regression of the latter following the achievement of a sustained virologic response (SVR). For several years, interferon-α alone or combined with ribavirin has been the standard of care. However, the rates of clinical, biochemical, and virologic responses have been low, and the occurrence of relapse frequent. The addition of rituximab has resulted in a higher rate of responses. With the advent of direct-acting antiviral agents, SVR has been achieved in ~ 95% of CV patients. However, in a minority of patients, despite SVR, CV may persist or reappear over variable lengths of time from the completion of therapy. The eventual appearance of B-NHL is also possible.

Histopathology of the skin in rheumatic diseases.

Rheumatological systemic autoimmune diseases, such as connective tissue diseases, rheumatoid arthritis or spondyloarthritis, are characterized by the presence of joint involvement associated with extra-articular manifestations. Among them, cutaneous diseases are often the most relevant and representative clinical manifestation, as in psoriatic arthritis, scleroderma or systemic lupus erythematosus. In this context, it is useful for rheumatologists to understand better skin diseases and their histopathological features. Evaluation of skin biopsy specimens can be helpful not only to confirm the diagnosis in both classic and clinically atypical variants, but also to improve further our knowledge of the pathogenetic mechanisms and the close link between skin and articular diseases. In this review, we discuss the clinical features, diagnostic evaluation and the histopathological features of skin manifestation of the most relevant rheumatological autoimmune diseases.

The evaluation of disease activity in Sjögren's syndrome based on the degree of MALT involvement: glandular swelling and cryoglobulinaemia compared to ESSDAI in a cohort study.

OBJECTIVES: To investigate if indicators of a heavier involvement of mucosa-associated lymphoid tissue (MALT) in primary Sjögren's syndrome (pSS), i.e. persistent salivary gland (SG) swelling and cryoglobulinaemia, might better evaluate the lymphoma risk compared to the ESSDAI. Therefore, the current concept of disease activity of pSS should be re-evaluated, based solely on ESSDAI. METHODS: A cohort of 255 pSS patients, including 30 pSS with B-cell lymphoma, was investigated. Three subgroups were distinguished, i.e. pSS developing lymphoma in the follow-up (n=12), pSS with lymphoma at cohort inclusion (n=18), and control pSS not developing lymphoma in the follow-up (n=225). SG swelling, cryoglobulinaemia and ESSDAI were evaluated at baseline, in the follow-up to one year before lymphoma diagnosis, and at lymphoma diagnosis. RESULTS: SG swelling and/or cryoglobulinaemia at baseline were significantly higher (p=0.0003) in pSS patients evolving into lymphoma if compared to pSS controls, while ESSDAI showed no significant difference. Both SG swelling and cryoglobulinaemia persisted and sometimes developed ex novo in the follow-up. SG swelling and cryoglobulinaemia were present in 24/30 (80%) cases the time of lymphoma diagnosis, and lymphoma itself was usually of MALT/marginal zone histotype (90%), leading to peculiar manifestation of lymphoma in pSS. CONCLUSIONS: The autoimmune and lymphoproliferative involvement of MALT is the biological substrate of pSS. If this involvement is heavier, as reflected by SG swelling and cryoglobulinaemia, disease activity may be considered higher, and the risk of lymphoma is increased. The current concept and evaluation of activity of pSS, based solely on the ESSDAI, needs revision.

Increased genomic instability following treatment with direct acting anti-hepatitis C virus drugs.

Mixed Cryoglobulinemic Vasculitis (MCV) is a prominent extra-hepatic manifestation of Hepatitis C virus (HCV) infection. HCV has been reported to cause B-cell disorders and genomic instability. Here, we investigated B-cell activation and genome stability in HCV-MCV patients receiving the direct antiviral agent, Sofosbuvir, at multiple centers in Egypt. Clinical manifestations in HCV-MCV patients were improved at the end of treatment (EOT), such as purpura (100%), articular manifestations (75%) and neuropathy (68%). Eighteen patients (56%) showed vasculitis relapse after EOT. BAFF and APRIL were higher at EOT and continued to increase one year following treatment onset. Chromosomal breaks were elevated at EOT compared to baseline levels and were sustained at 3 and 6 months post treatment. We report increased expression of DNA genome stability transcripts such as topoisomerase 1 and TDP1 in HCV-MCV patients after treatment, which continued to increase at 12 months from treatment onset. This data suggest that B-cell activation and DNA damage are important determinants of HCV-MCV treatment outcomes.