Cryoglobulins and cryoglobulinemia. Diagnostic and therapeutic considerations

Ultrastructural overlap between immunotactoid and cryoglobulin glomerulopathy: A case report

Immunotactoid glomerulopathy (ITG), a condition characterised by highly organised microtubules on electron microscopy, and cryoglobulin glomerulopathy (CG) are rare forms of kidney injury that may be encountered in patients with cryoglobulinaemia. It has been proposed these two entities are part of the same disease process following observed clinical and histological similarities.

Polyneuropathy: A Rare and Challenging Presentation of Essential Mixed Cryoglobulinemia

A 49-year-old male presented with acute chronic sensory motor bilateral lower extremity polyneuropathy. Electromyography showed bilateral acute sensory motor axonal polyneuropathy. Lumbar spine magnetic resonance imaging showed diffuse bone marrow replacement and bilateral ankylosing spondylitis. Laboratory workup revealed elevated inflammatory markers and low G6PD (glucose-6-phosphate dehydrogenase) level. Due to elevated acute phase reactants, inflammatory polyneuropathy was suspected; patient was treated accordingly with resolution of neuropathy. Three months later, he relapsed and presented with disabling polyneuropathy and renal impairment, which prompted renal biopsy. Renal histopathology revealed the, otherwise mysterious, etiology, essential mixed cryoglobulinemia. Essential mixed cryoglobulinemia was not considered initially due to the absence of classic systemic manifestations of autoimmune disorders.

No. 96-The Reproductive Care of Women Living With Hepatitis C Infection

OBJECTIVE

hepatitis C virus (HCV) is an increasingly important public health problem worldwide. Health care workers providing care to women of childbearing age are uniquely placed in their practices to identify a significant proportion of at-risk patients and to provide appropriate screening and counselling. The primary objective of this guideline is to provide accurate, current information to those offering reproductive care to women living with HCV. This document is also intended to raise awareness of HCV in both the medical and general populations.

OPTIONS

the areas of clinical practice considered in formulating this guideline are disease prevention, targeted screening of individuals at risk of contracting HCV, management of identified patients in the context of reproductive care, and the appropriate referral of patients to those with particular expertise.

OUTCOMES

implementation of these guidelines should facilitate identification of infected individuals. It should also result in improved physical and mental well-being for patients and their families and reduction in transmission rates.

EVIDENCE

the literature between 1966 and 2000, including non- English language publications, was extensively searched utilizing Medline. A multidisciplinary group consisting of experts within the fields of obstetrics and gynaecology, infectious diseases, hepatology, and public health convened in Montreal in February 2000. The working group also included a patient and a representative from the Hepatitis C Society of Canada. The level of evidence for the recommendations has been determined using the criteria described by the Canadian Task Force on Periodic Health Examination.

BENEFITS, HARMS AND COSTS

the public health benefits of increased identification of at-risk individuals, diagnosis, treatment, implementation of risk reduction behaviours, and reduced transmission rates, both on an individual and at the community level, are significant. However, it must be remembered that the diagnosis of a chronic disease may have far reaching effects for the individual patient and her family.

RECOMMENDATIONS

VALIDATION: references were collected through Medline searches and comparison made to existing current guidelines for assessment of consistency. External reviewers expert in their field were also consulted.

Hepatic manifestations in hematological disorders

Liver involvement is often observed in several hematological disorders, resulting in abnormal liver function tests, abnormalities in liver imaging studies, or clinical symptoms presenting with hepatic manifestations. In hemolytic anemia, jaundice and hepatosplenomegaly are often seen mimicking liver diseases. In hematologic malignancies, malignant cells often infiltrate the liver and may demonstrate abnormal liver function test results accompanied by hepatosplenomegaly or formation of multiple nodules in the liver and/or spleen. These cases may further evolve into fulminant hepatic failure.

Cutaneous manifestations of vasculitis

OBJECTIVES

To discuss the clinical features, diagnostic evaluation, and treatment options for cutaneous vasculitis.

METHODS

The literature in the PubMed database was reviewed regarding the presentation, pathophysiology, clinical workup, and treatment of cutaneous vasculitis.

RESULTS

Available classification criteria of vasculitis are based on histopathologic criteria or clinicohistologic features. These have been designed more for research purposes than for clinical application. Skin findings such as palpable purpura, nodules, urticaria, ulcers, and infarction are clues to the presence of vasculitis. Pathologic findings of fibrinoid necrosis, infiltration by neutrophils or lymphocytes, and deposition of complement and immunoglobulin may be helpful in reaching a specific diagnosis. However, there is considerable overlap across different conditions.

CONCLUSIONS

The correct diagnosis of cutaneous manifestations of vasculitis requires an understanding of vasculitis classification, recognition of specific clinical patterns, and the ability to interpret histopathologic data.

Oral interferon-alpha treatment of mice with cryoglobulinemic glomerulonephritis

Cryoglobulins are associated with the development of a membranoproliferative glomerulonephritis, often referred to as cryoglobulinemic glomerulonephritis, particularly in the setting of hepatitis C virus infection. Parenteral interferon-alpha (IFN-alpha) commonly is used therapeutically in humans with cryoglobulinemic glomerulonephritis. We tested the therapeutic impact of oral IFN-alpha treatment in thymic stromal lymphopoietin (TSLP) transgenic mice, a strain that develops mixed cryoglobulinemia with glomerulonephritis closely resembling the disease that occurs in humans. A total of 41 female mice were treated for 21 days with daily ingestion of either 500 IU of Universal type I IFN or placebo. The studied groups included TSLP transgenic mice treated with IFN-alpha (n = 13), TSLP transgenic mice treated with placebo (n = 13), wild-type mice treated with IFN-alpha (n = 5), and wild-type mice treated with placebo (n = 10). A total of 39 mice completed the study; two TSLP transgenic mice treated with IFN-alpha died during the study period. Placebo-treated TSLP transgenic mice showed significantly increased mean glomerular tuft areas, mean glomerular areas occupied by macrophages, and mean cell numbers per glomerulus compared with wild-type controls. All three parameters were decreased in IFN-alpha-treated TSLP transgenic mice, although the differences compared with placebo-treated mice did not reach significance. The changes in glomerular matrix deposition were the same in IFN-alpha-treated and placebo-treated mice. The oral ingestion of IFN-alpha seemed to reduce glomerular macrophage influx, but this did not result in decreased glomerular matrix deposition. The limited positive effect provides experimental support for clinical studies that indicate the beneficial effects of IFN-alpha therapy observed in humans with glomerulonephritis might be attributable to its antiviral effect rather than modulation of intrarenal pathophysiologic pathways.

Cryoglobulinemic glomerulonephritis in thymic stromal lymphopoietin transgenic mice

Mixed cryoglobulins are complexes of immunoglobulins that reversibly precipitate in the cold and lead to a systemic disease in humans. Renal involvement usually manifests as a membranoproliferative glomerulonephritis with marked monocyte infiltration and, at times, intracapillary thrombi. Thymic stromal lymphopoietin (TSLP) is a recently cloned cytokine that supports differentiation and long-term growth of B cells. Here we report that TSLP overexpression in mice results in the development of mixed cryoglobulins, with renal involvement closely resembling cryoglobulinemic glomerulonephritis as it occurs in humans. One hundred twenty-three mice were sacrificed at monthly intervals, with at least five TSLP transgenic mice and five controls in each group. Blood, kidneys, spleen, liver, lung, and ear were collected and studied by routine microscopy, immunofluorescence, immunohistochemistry, and electron microscopy. TSLP transgenic animals developed polyclonal mixed cryoglobulinemia (type III) and a systemic inflammatory disease involving the kidney, spleen, liver, lung, and ears. Renal involvement was of a membranoproliferative type demonstrating thickened capillary walls with cellular interposition and double contours of the basement membrane, expansion of the mesangium because of increased matrix and accumulation of immune-deposits, subendothelial immune-deposits, focal occlusion of capillary loops, and monocyte/macrophage influx. In contrast to the severe glomerular lesions, the tubulointerstitium was not involved in the disease process. The renal lesions and the disease course were more severe in females when compared to males. We describe a mouse strain in which a B-cell-promoting cytokine leads to formation of large amounts of mixed cryoglobulins and a systemic inflammatory injury that resembles important aspects of human cryoglobulinemia. This is the first reproducible mouse model of renal involvement in mixed cryoglobulinemia, which enables detailed studies of a membranoproliferative pattern of glomerular injury.

Monoclonal immunoglobulin G cryoglobulinemia and multiple myeloma in a domestic shorthair cat

A 13-year-old castrated domestic shorthair cat was examined because of fever, anorexia, and dermatologic lesions. Crusting, erythema, and well-demarcated purple discoloration of the foot pads and the tips of the pinnae, nose, and tail were seen. A white flocculent precipitate was detected in cooled serum. This precipitate dissolved upon rewarming, consistent with a cryoglobulin. Hypercalcemia, high alanine and aspartate aminotransferase activities, thrombocytopenia, and a monoclonal IgG gammopathy were found. Numerous hepatic nodules were detected by means of abdominal ultrasonography. Cytologic evaluation of fine-needle aspirates of the liver and spleen revealed numerous plasma cells, and evaluation of a bone marrow aspirate revealed plasmacytosis. A diagnosis of multiple myeloma and monoclonal IgG cryoglobulinemia was made, and the cat was euthanatized.