Autoimmune diseases of the peripheral nervous system

Animal models of immune-mediated demyelinating polyneuropathies

Immune-mediated demyelinating polyneuropathies (IMDPs) are rare disorders in which dysregulated adaptive immune responses cause peripheral nerve demyelinating inflammation and axonal injury in susceptible individuals. Despite significant advances in understanding IMDP pathogenesis guided by patient data and representative mammalian models, specific therapies are lacking. Significant knowledge gaps in IMDP pathogenesis still exist, e.g. precise antigen(s) and mechanisms that initially trigger immune system activation and identification of large population disease susceptibility factors. The initial directional cues for antigen-specific effector or autoreactive leukocyte trafficking into peripheral nerves are also unknown. An overview of current animal models, with emphasis on the experimental autoimmune neuritis and spontaneous autoimmune peripheral polyneuropathy models, is provided. Insights on the initial directional cues for peripheral nerve tissue specific autoimmunity using a novel Major Histocompatibility Complex class II conditional knockout mouse strain are also discussed, suggesting an essential research tool to study cell- and time-dependent adaptive immunity in autoimmune diseases.

What is known about the effects of vitamin D in neuropsychiatric lupus?

Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect several organs and systems. The central and/or peripheral nervous system can suffer from complications known as neuropsychiatric lupus (NPSLE). Studies have associated the manifestations of SLE or NPSLE with vitamin D deficiency. It has been shown that hypovitaminosis D can lead to cognition deficits and cerebral hypoperfusion in patients with NPSLE. In this review article, we will address the main features related to vitamin D supplementation or serum vitamin D levels with neuropsychiatric manifestations, either in patients or in animal models of NPSLE.

In persons with CIDP, auto-HSCT can be conducted fully on an outpatient basis and induces significant clinical responses: A prospective study in a single center

BACKGROUND

Chronic inflammatory demyelinating polyneuropathy (CIDP) is one of the world's most common treatable neuropathy which usually responds to immunosuppressive treatment. Autologous hematopoietic stem cell transplantation (aHSCT) is an intense way of inducing immunosuppression.

OBJECTIVE

We analyze the evolution of CIDP patients treated with aHSCT in our center.

METHODS

Between 2018 and 2023, persons with CIDP were prospectively autografted employing the "Mexican method" to conduct grafts on an outpatient basis, employing cyclophosphamide 200 mg/Kg and rituximab 1000 mg. The protocol is registered in ClinicalTrials.gov identifier NCT02674217.

RESULTS

In our center 21 autologous transplant cases were completed in 2018-2023. Seven patients provided data to assess the efficacy of the procedure. Positive responses (stabilization and/or improvement) were observed in all seven patients: Five reported improvements in the Inflammatory Neuropathy Cause and Treatment (INCAT) score and one reported stabilization. In the Inflammatory Rasch-Built Overall Disability Scale (I-RODS) score. Median INCAT score was 5 (range 1-9), whereas median I-RODS score was 24 (range 11-29). Five patients (71%) reported improvement in the INCAT score, one reported stabilization and one informed worsening; concerning the I-RODS score 5 (71%) informed improvement, whereas two reported stabilization.

CONCLUSION

aHSCT conducted fully in an outpatient basis, employing the conditioning regimen of the "Mexican method" appears to be a feasible therapeutic option for persons with CIDP. Additional studies are needed to confirm these observations.

Gut Microbiota and Autoimmune Diseases: A Charming Real World Together with Probiotics

BACKGROUND

The role of gut microbiota in human disease is fascinating for hundreds of researchers worldwide. Many works have highlighted that gut microbiota modulates the immune system and that its disruption can trigger autoimmune and inflammatory immune-mediated diseases. Probiotics are able to positively modify microbiota composition.

OBJECTIVE

The aim of this review is to report the most important findings regarding the effects of probiotics administration in the most common autoimmune disease and inflammatory immune-mediated diseases.

METHODS

Literature research was performed in PubMed, Google Scholar, and Medline, as well as in specific journal websites using the keywords: "autoimmunity", "microbiota", and "probiotics". The article selection has been made independently by three authors, and controversies have been solved by a fourth researcher. Only English-language articles were included and preference was given to clinical trials, meta-analysis, and case series. After the review process, 68 articles have been considered.

RESULTS

Relying on this evidence, many studies have investigated the potential of probiotics in restoring gut eubiosis, thus affecting pathogenesis, clinical manifestations, and course of these pathologies. Even in the light of few and sometimes contradictory studies, physicians should start to consider these preliminary findings when approaching patients suffering from autoimmune disease. After an accurate case-by-case evaluation of potential candidates, probiotics might be introduced besides the standard therapeutic plan as supportive measures.

Immunological and Hematological Response to Local Transplantation of Stem Cells in Injured Radial Nerve of Dogs

The current study was carried out to investigate the immunological and hematological changes due to local transplantation of human umbilical cord-mesenchymal-stem cells (HUC-MSCs) and scaffold-stem cells (SSCs) into the injured radial nerve. Therefore, three equal groups of dogs were subjected to this study; experimental (EG), positive control (PCG) and negative control (NCG). At 1st week, dogs of EG were showed an obvious mobility dysfunction. At 2nd and 4th weeks, there were apparent improvements reported on general and physical activities as well as functional ability of forelimb with the presence of slight lameness that was cured completely at 5th week. Regarding to immunobiomarkers, insignificant differences were showed at 1st week. However, significantly increase in IgG and TNF-α, and decrease in IL-10 was reported at 2nd, 4th, and 6th weeks. Regarding to hematologic parameters, significantly increases were recorded in total WBCs from 2nd week onwards, lymphocytes and neutrophils at 2nd week, monocytes at the 2nd and 4th weeks, and total RBCs at the 8th and 16th weeks. Significant differences were not reported in values of PCV and Hb throughout this study. In conclusion, HUC-MSCs and SSCs confirmed high activities in supporting of immunological and hematological responses, and in restoration of nerve function

Neurological manifestations and implications of COVID-19 pandemic

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China and rapidly spread worldwide, with a vast majority of confirmed cases presenting with respiratory symptoms. Potential neurological manifestations and their pathophysiological mechanisms have not been thoroughly established. In this narrative review, we sought to present the neurological manifestations associated with coronavirus disease 2019 (COVID-19). Case reports, case series, editorials, reviews, case-control and cohort studies were evaluated, and relevant information was abstracted. Various reports of neurological manifestations of previous coronavirus epidemics provide a roadmap regarding potential neurological complications of COVID-19, due to many shared characteristics between these viruses and SARS-CoV-2. Studies from the current pandemic are accumulating and report COVID-19 patients presenting with dizziness, headache, myalgias, hypogeusia and hyposmia, but also with more serious manifestations including polyneuropathy, myositis, cerebrovascular diseases, encephalitis and encephalopathy. However, discrimination between causal relationship and incidental comorbidity is often difficult. Severe COVID-19 shares common risk factors with cerebrovascular diseases, and it is currently unclear whether the infection per se represents an independent stroke risk factor. Regardless of any direct or indirect neurological manifestations, the COVID-19 pandemic has a huge impact on the management of neurological patients, whether infected or not. In particular, the majority of stroke services worldwide have been negatively influenced in terms of care delivery and fear to access healthcare services. The effect on healthcare quality in the field of other neurological diseases is additionally evaluated.

Deciphering immune mechanisms in chronic inflammatory demyelinating polyneuropathies

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune disease of the peripheral nerves that presents with either chronic progression or relapsing disease. Recent studies in samples from patients with CIDP and mouse models have delineated how defects in central (thymic) and peripheral (extrathymic) immune tolerance mechanisms can cause PNS autoimmunity. Notably, nerve parenchymal cells actively contribute to local autoimmunity and also control disease outcome. Here, we outline how emerging technologies increasingly enable an integrated view of how immune cells and PNS parenchymal cells communicate in CIDP. We also relate the known heterogeneity of clinical presentation with specific underlying mechanisms. For example, a severe subtype of CIDP with tremor is associated with pathogenic IgG4 autoantibodies against nodal and paranodal proteins. An improved understanding of pathogenic mechanisms in CIDP will form the basis for more effective mechanism-based therapies.

Incidence, Risk Factors, and Outcome of Immune-Mediated Neuropathies (IMNs) following Haploidentical Hematopoietic Stem Cell Transplantation

Immune-mediated neuropathies (IMNs) following hematopoietic stem cell transplantation have been described recently, which, excluding Guillain-Barré syndrome and chronic inflammatory demyelinating polyneuropathy, may present with atypical patterns. This retrospective, nested, case-control study reviewed data from 3858 patients who received haploidentical hematopoietic stem cell transplantation (haplo-HSCT) during the past 10 years at a single center, and 40 patients (1.04%) with IMN following haplo-HSCT were identified. Chronic graft-versus-host disease (cGVHD) (P = .043) and cytomegalovirus (CMV) viremia (P = .035) were recognized as independent risk factors for the development of IMN after haplo-HSCT. There were no significant differences in overall survival (P = .619), disease-free survival (P = .609), nonrelapse mortality (P = .87), or the incidence of relapse (P = .583) between patients with and without IMN after haplo-HSCT. However, patients with post-transplant IMN were at higher risk of developing cGVHD (P = .012) than patients who did not develop IMN. Twenty-four of the 40 patients with IMN (60%) attained neurologic improvement after treatments including vitamins B₁ and B₁₂ and/or immunomodulatory agents. However, 19 (47.5%) patients still had persistent motor/sensory deficits despite receiving timely treatment. More studies are needed to help develop standardized diagnostic and therapeutic strategies for patients with post-transplant IMN.

Peripheral nervous system involvement in systemic lupus erythematosus: Prevalence, clinical and immunological characteristics, treatment and outcome of a large cohort from a single centre

Disorders of peripheral nervous system in patients with systemic lupus erythematosus (PNS-SLE) are a major cause of morbidity. The aims of the present study were to determine the prevalence of PNS-SLE involvement in a large cohort of SLE patients from a single centre, to characterize such involvement, treatment modalities and outcome, and to identify the possible variables that may be associated with its presence. We performed an observational cross-sectional study that included all SLE patients being followed in our department between March and December 2015 who met at least one of the PNS-SLE case definitions proposed in 1999 by the American College of Rheumatology. Overall, 93 out of 524 (17,7%) patients presented with PNS-SLE syndrome; 90 (96.8%) of them were women with a mean age at PNS-SLE syndrome diagnosis was 44.8±14.1years and the average time from diagnosis of SLE to PNS-SLE diagnosis was 88 (range, 541-400) months. The most frequent manifestation was polyneuropathy (36.6%), followed by non-compression mononeuropathy (23.7%), cranial neuropathy and myasthenia gravis (7.5%, each), and Guillain-Barré syndrome (1.1%). The most frequent electrodiagnostic tests (EDX) pattern was axonal degeneration, present in 49 patients that corresponded to 80.3% of the overall EDX patterns. Mixed sensory-motor neuropathy was the most common type of involvement accounted for 56% of cases. Thirty-six out of 90 (40%) received glucocorticoids and/or immunosuppressant agents. Overall, global response (complete and/or partial) to treatments was achieved in 77.4% of patients without differences between the types of PNS-SLE involvement. Older age at SLE diagnosis (37.3±14.8 versus 30.8±12; p=0.001) and absence of hematologic involvement as cumulative SLE manifestation (11.8% versus 21.5%; p=0.034) had independent statistical significant associations with PNS-SLE development. The PNS-SLE involvement is not uncommon. Its most frequent manifestation is sensory-motor axonal polyneuropathy. The involvement occurs more frequently in patients who are diagnosed with SLE at older age. Prospective studies are needed to establish the incidence of PNS-SLE syndromes and the role of hematological manifestations in their development.

A Brain-Derived Neurotrophic Factor-Based p75NTR Peptide Mimetic Ameliorates Experimental Autoimmune Neuritis Induced Axonal Pathology and Demyelination

Axonal damage and demyelination are major determinants of disability in patients with peripheral demyelinating neuropathies. The neurotrophin family of growth factors are essential for the normal development and myelination of the peripheral nervous system (PNS), and as such are potential therapeutic candidates for ameliorating axonal and myelin damage. In particular, BDNF promotes peripheral nerve myelination via p75 neurotrophin receptor (p75NTR) receptors. Here, we investigated the therapeutic efficacy of a small structural mimetic of the region of BDNF that binds to p75NTR (cyclo-dPAKKR) in experimental autoimmune neuritis (EAN), an established animal model of peripheral demyelinating neuropathy. Examination of rodents induced with EAN revealed that p75NTR is abundantly expressed in affected peripheral nerves. We found that systemic administration of cyclo-dPAKKR ameliorates EAN disease severity and accelerates recovery. Animals treated with cyclo-dPAKKR displayed significantly better motor performance compared to control animals. Histological assessment revealed that cyclo-dPAKKR administration limits the extent of inflammatory demyelination and axonal damage, and protects against the disruption of nodal architecture in affected peripheral nerves. In contrast, a structural control peptide of cyclo-dPAKKR exerted no influence. Moreover, all the beneficial effects of cyclo-dPAKKR in EAN are abrogated in p75NTR heterozygous mice, strongly suggesting a p75NTR-dependent effect. Taken together, our data demonstrate that cyclo-dPAKKR ameliorates functional and pathological defects of EAN in a p75NTR-dependant manner, suggesting that p75NTR is a therapeutic target to consider for future treatment of peripheral demyelinating diseases and targeting of p75NTR is a strategy worthy of further investigation.

Plasma Fibrinogen in Patients With Bell Palsy

OBJECTIVE

To determine the plasma fibrinogen level in patients with Bell palsy and explore the significances of it in Bell palsy.

METHODS

One hundred five consecutive patients with facial paralysis were divided into 3 groups: group I (Bell palsy), group II (temporal bone fractures), and group III (facial nerve schwannoma). In addition, 22 volunteers were defined as control group. Two milliliters fasting venous blood from elbow was collected, and was evaluated by CA-7000 Full-Automatic Coagulation Analyzer.

RESULTS

The plasma fibrinogen concentration was significantly higher in the group of patients with Bell palsy (HB IV-VI) than that in the control group (P <0.05). There was no significant difference between group II and control group (P >0.05); similarly, there was also no marked difference between group III and control group (P >0.05). In group I, the plasma fibrinogen levels became higher with the HB grading increase. The plasma fibrinogen level of HB-VI was highest.

CONCLUSIONS

Plasma fibrinogen has an important clinical meaning in Bell palsy, which should be used as routine examination items. Defibrinogen in treatment for patients with high plasma fibrinogen content also should be suggested.

Novel immunotherapeutic strategies in chronic inflammatory demyelinating polyneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a chronic immune-mediated neuropathy: it is clinically heterogeneous (relapsing-remitting form, chronic progressive form, monophasic form or CIDP having a Guillain-Barré syndrome-like onset), but potentially treatable. Although its pathophysiology remains largely unknown, CIDP is considered an immune-mediated neuropathy. Therefore, many immunotherapies have been proposed in this peripheral nervous system disorder, the most known efficient treatments being intravenous immunoglobulin, corticosteroids and plasma exchange. However, these therapies remain unsatisfactory for many patients, so numerous other immunotherapeutic strategies have been evaluated, based on their immunosuppressant or immunomodulatory potency. We have performed a large review of the literature about treatment in CIDP, with a special emphasis on novel and alternative immunotherapeutic strategies.

New strategies in the management of Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is an acute and usually monophasic, neurological, demyelinating disease. Although most patients have good outcomes without sequelae after conventional plasma exchange and intravenous immunoglobulin therapy, 20% of patients continue to have severe disease and 5% die of their disease. Therefore, there is an obvious need for more acceptable and efficacious therapies. Experimental autoimmune neuritis (EAN) is the classical animal model for GBS. As there is no specific drug for GBS, several drugs targeting the humoral and cellular components of the immune response have been used to treat EAN in the endeavour to find new treatment alternatives for GBS. This review focused on some new strategies for GBS, which have been reported but have not yet been widely used, and on the main drugs which have been investigated in EAN.

Lymphoma-associated dysimmune polyneuropathies

Lymphoma consists of a variety of malignancies of lymphocyte origin. A spectrum of clinical peripheral neuropathy syndromes with different disease mechanisms occurs in about 5% of lymphoma patients. There exists a complex inter-relationship between lymphoproliferative malignancies and autoimmunity. An imbalance in the regulation of the immune system presumably underlies various immune-mediated neuropathies in patients with lymphoma. This article reviews lymphoma and more-or-less well-defined dysimmune neuropathy subgroups that are caused by humoral and/or cell-mediated immune disease mechanisms directed against known or undetermined peripheral nerve antigens.

Psoriasis and the risk of pneumonia: a population-based study

BACKGROUND

Psoriasis is a prevalent autoimmune disorder. Various studies have reported on the relationship between psoriasis and chronic diseases but very few have explored the association between psoriasis and subsequent acute infection. This retrospective cohort study aimed to compare the risk of pneumonia between subjects with and those without psoriasis.

METHODS

The medical records of 14,022 patients with psoriasis and 14,022 without psoriasis were obtained from the Taiwan Longitudinal Health Insurance Database 2000. Each patient was followed-up for a three-year period. Cox proportional hazard regressions were performed to compare difference of subsequent pneumonia incidence between subjects with and those without psoriasis.

RESULTS

There were 206 (1.47%) subjects with psoriasis and 138 (0.98%) without psoriasis hospitalized for pneumonia. By Cox proportional hazard regressions analysis, the HR (hazard ratio) of pneumonia requiring hospitalization for patients with psoriasis was 1.50 (95% confidence interval [CI]: 1.21-1.86) compared to patients without psoriasis. The adjusted HR was 1.40 (95% CI: 1.12-1.73). The adjusted HR of pneumonia hospitalization for subjects with mild and severe psoriasis was 1.36 (95% CI: 1.09-1.70) and 1.68 (95% CI: 1.12-2.52), respectively, compared to those without psoriasis.

CONCLUSIONS

Patients with psoriasis have significantly higher incidence of pneumonia compared to those without psoriasis.

IVIG regulates BAFF expression in patients with chronic inflammatory demyelinating polyneuropathy (CIDP)

Recent studies indicate that the cytokine B-cell activating factor (BAFF) is involved in the pathogenesis of chronic inflammatory demyelinating polyneuropathy (CIDP). Intravenous immunoglobulin (IVIg) is standard treatment for CIDP and is known to rapidly modulate increased serum levels of pro-inflammatory cytokines. We evaluated the expression profile of BAFF and its corresponding BAFF-receptor in samples from CIDP patients, focusing on rapid changes before and after IVIg treatment. In CIDP patients BAFF serum concentrations were elevated compared to controls. Treatment with high-dose IVIg restored those elevated BAFF serum levels. Whereas treatment with IVIg did not affect BAFF production in monocytes, antibodies against BAFF could be detected in IVIg preparations, which may explain the short-term decrease of BAFF levels after IVIg treatment. Our data suggest that BAFF plays an important role in the pathogenesis of CIDP and may serve as marker for IVIg treatment response.

Treatment for experimental autoimmune neuritis with clodronate (Bonefos)

Experimental autoimmune neuritis (EAN) serves as an animal model for human Gullain-Barre syndrome (GBS), an autoimmune disease causing demyelination and inflammation of peripheral nerves. Macrophages, which play a major role in this autoimmune inflammatory process, can be selectively targeted by high doses of bisphophonates. The goal of this study was to examine the effect of the bisphosphonate, clodronate, on the severity of the EAN model. EAN was induced in female adult rats by immunization with bovine peripheral myelin. A number of treatment protocols with clodronate were used based on the common dosage regimen of 20 mg/kg in humans starting with the appearance of clinical signs on day 10 post-immunization. The clinical parameters measured included a clinical score, a motor performance test performed on a Rotarod and body weight. The expression of the matrix metaloprotease (MMP-9) in the sciatic nerves was measured as a marker of inflammatory macrophages. Treatment with clodronate, 20 mg/kg daily and 40 mg/kg every 2 days, significantly reduced the disease severity (a 75% decrease in severity, p < 0.01 by ANOVA) as measured by the clinical score compared to controls. Performance on the Rotarod test and body weight confirmed the clinical score findings. MMP-9 expression levels were significantly lower in the sciatic nerves of clodronate-treated rats. The present findings support the efficiency of clodronate in inflammatory diseases of the peripheral nervous system. The mechanism of action includes inhibition of inflammatory macrophages. The results suggest the use of bisphosphonates be considered in humans with GBS.

Treatment of chronic inflammatory demyelinating polyneuropathy: from molecular bases to practical considerations

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune disease of the peripheral nervous system, in which both cellular and humoral immune responses are involved. The disease is clinically heterogeneous with some patients displaying pure motor form and others also showing a variable degree of sensory dysfunction; disease evolution may also differ from patient to patient, since monophasic, progressive, and relapsing forms are reported. Underlying such clinical variability there is probably a broad spectrum of molecular dysfunctions that are and will be the target of therapeutic strategies. In this review we first explore the biological bases of current treatments and subsequently we focus on the practical management that must also take into account pharmacoeconomic issues.

A review of the use of biological agents for chronic inflammatory demyelinating polyradiculoneuropathy

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a group of idiopathic, acquired, immune-mediated inflammatory demyelinating diseases of the peripheral nervous system. A majority of patients with CIDP respond to "first-line" treatment with IVIG, plasmapheresis and/or corticosteroids. There exists insufficient evidence to ascertain the benefit of treatment with "conventional" immunosuppressive drugs. The inconsistent efficacy, long-term financial burden and health risks of non-specific immune altering therapy have drawn recurrent attention to the possible usefulness of a variety of biological agents that target key aspects in the CIDP immunopathogenic pathways. This review aims to give an updated account of the scientific rationale and potential use of biological therapeutics in patients with CIDP. No specific treatment recommendations are given. The discovery, development and application of biological markers by modern molecular diagnostic techniques may help identify drug-naïve or treatment-resistant CIDP patients most likely to respond to targeted immunotherapy.

PCR based bronchoscopic detection of common respiratory pathogens in chronic cough: a case control study

BACKGROUND

Viral respiratory tract infection is the most frequent cause of acute cough and is reported at onset in about one third of patients with chronic cough. Persistent infection is therefore one possible explanation for the cough reflex hypersensitivity and pulmonary inflammation reported in chronic cough patients.

METHODS

Bronchoscopic endobronchial biopsies and bronchoalveolar lavage cell counts were obtained from ten healthy volunteers and twenty treatment resistant chronic cough patients (10 selected for lavage lymphocytosis). A screen for known respiratory pathogens was performed on biopsy tissue. Chronic cough patients also underwent cough reflex sensitivity testing using citric acid.

RESULTS

There was no significant difference in incidence of infection between healthy volunteers and chronic cough patients (p = 0.115) or non-lymphocytic and lymphocytic groups (p = 0.404). BAL cell percentages were not significantly different between healthy volunteers and chronic cough patients without lymphocytosis. Lymphocytic patients however had a significantly raised percentage of lymphocytes (p < 0.01), neutrophils (p < 0.05), eosinophils (p < 0.05) and decreased macrophages (p < 0.001) verses healthy volunteers. There was no significant difference in the cough reflex sensitivity between non-lymphocytic and lymphocytic patients (p = 0.536).

CONCLUSIONS

This study indicates latent infection in the lung is unlikely to play an important role in chronic cough, but a role for undetected or undetectable pathogens in either the lung or a distal site could not be ruled out.

TRIALS REGISTRATION

Current Controlled Trials ISRCTN62337037 & ISRCTN40147207.

Treatment with rituximab in patients with mixed cryoglobulinemia syndrome: results of multicenter cohort study and review of the literature

OBJECTIVE

Mixed cryoglobulinemia syndrome (MCs) is a systemic vasculitis characterized by multiple organ involvement due to the vascular deposition of immune-complexes, mainly the cryoglobulins. B-lymphocyte expansion represents the underlying pathological alteration frequently triggered by hepatitis C virus (HCV) infection. The treatment of MCs syndrome is generally based on antiviral drugs and/or immunosuppressors, among which rituximab, an anti-CD20 monoclonal antibody, has been usefully employed for both cutaneous and visceral MCs organ involvement. This multicenter study retrospectively evaluated the effects of rituximab in a large series of patients with active MCs. The observed results were compared to those emerging from the updated review of the literature on this topic.

METHODS

The study included 87 patients (male/female 19/68, mean age 62.3±11.4SD years, mean disease duration 9±6.2SD years, HCV infection in 92% of cases) with active cryoglobulinemic vasculitis evaluated before rituximab monotherapy and after 6-month follow-up by means of main clinico-serological parameters. A PubMed search up to May 31, 2011, was done to find published clinical studies, including case reports of MCs treated with rituximab.

RESULTS

A significant clinical improvement was observed in a relevant percentage of cases, regardless the presence/absence of associated HCV infection; namely, complete/partial remission of pre-treatment active manifestations was observed in 74% of skin purpuric lesions, up to 87% of non-healing vasculitic leg ulcers, and 44% of the peripheral neuropathy, mainly paresthesias (patient's visual analogical scale from 62±25 to 37±27; p≤.0001). Moreover, cryoglobulinemic nephropathy, observed in 38 patients, significantly improved in 95% of cases (serum creatinine from 1.8±1.1SD to 1.4±0.8SD mg/dl, p≤.0001; 24-hour proteinuria from 2.2±2.1SD to 0.9±1.7SD g/24h, p≤.0001), with complete remission in the 50%. Among 6 patients with complicating non-Hodgkin's B-cell lymphoma a complete or partial remission was observed in 5/6. A complete remission of abdominal vasculitis was also observed in one patient. These beneficial effects were mirrored by the improvement of cryoglobulinemic serological hallmarks, namely cryocrit and low complement C4, in half cases. The safety of rituximab was confirmed by the small number of side effects recorded during the 6-month follow-up. On the whole, the results of the present study are in keeping with those reported in 39 papers present in world literature, including a total of 279 MCs patients.

CONCLUSIONS

Rituximab may be regarded as useful and safe pathogenetic treatment of cryoglobulinemic vasculitis. The actual role of this drug should be definitely confirmed by randomized controlled trials, as well as its position in the therapeutical strategy, mainly with respect to antiviral treatment in HCV-associated MCs.