Trichinosis-related polyarteritis nodosa

Reviews on trichinellosis (II): neurological involvement

Neurological involvement may occur in 0.2%-52% of cases with trichinellosis, generally in the most severely affected patients. This review focuses on neurotrichinellosis and includes a brief overview of selected cases reported in the literature. Our primary goal was to increase the awareness of infectious diseases specialists, neurologists, and general practitioners about these major complications with possible fatal outcome. Seventy seven of the cases, for which enough details were available, have been pooled for statistical analysis. The mean age of the investigated group was 34.6 ± 16.8 years. Patients with both focal and diffuse manifestations predominated (55.8%), and they were significantly older (40 ± 15.5 years old) than those who presented solely focal (28.9 ± 17.8 years old; p = 0.03) or diffuse lesions (27.9 ± 15.3 years old; p = 0.007). In most of the cases (59.7%), complete recovery was reported, whereas 23.4% of cases had sequelae and 16.9% of the patients died. Patients who died had significantly lower eosinophil counts (13.8% ± 14%) when compared with those who made complete recovery (28.7% ± 18%; p = 0.015) and the cases with sequelae (35% ± 17.9%; p = 0.006). To sum up, trichinellosis must be considered in the differential diagnosis of any patient with encephalitis or other central nervous system malady of ambiguous etiology.

Infection and vasculitis

Vasculitis may be associated with infection, immunization or anti-microbial drugs. Infections are responsible for a number of different types of vasculitis. Conversely, patients with vasculitis may develop infections, which sometimes mimic relapse. The aim of this review is to summarize the various aspects of the inter-relationship between vasculitis and infection, and the physiopathological mechanisms involved, in light of our current knowledge from animal models. Currently, a causal relationship between infection and vasculitis has only been established in a few instances and many mechanisms remain hypothetical. This inter-relationship is further assessed from the point of view of clinical presentation and therapeutic options, based on case reports and prospective observational data.

[Systemic vasculitis during parasitosis]

A RARE EVENTUALITY: Although parasite infections are frequent, observations of vasculitis related to parasitosis are, however, very rare. REGARDING THE MECHANISM: The simultaneous occurrence of a parasitosis and vasculitis may be the consequence of either the direct implication of a parasite observed in the histological lesions in the onset of alteration in the vascular wall, or of immunopathological phenomena occuring during the anti-parasite immune response, or a fortuitous association. THE HUMAN PARASITOSIS IMPLIED: In most cases, vasculitis associated with parasitosis is an isolated event with varied clinical aspects. Such cases have been reported in toxoplasmosis, trichinosis, strongyliasis, ascaridiosis, sarcocystosis, amibiasis, leishmaniosis and toxocarosis.

Rheumatic manifestations of parasitic diseases

OBJECTIVES

To consolidate the spectrum and frequency of parasite-related rheumatic syndromes, which have largely been regarded as exceedingly rare by the general medicine, infectious disease, and rheumatology literature.

METHODS

A MEDLINE search was performed for articles on rheumatic syndromes related to parasitic infections published from 1966 through December 2000. Identified articles included clinical and epidemiologic studies describing cases of rheumatic syndromes associated with verified parasitic infection.

RESULTS

Rheumatologic syndromes, including inflammatory arthritis, inflammatory myositis, and vasculitis, have been described among multiple different parasite infections of all parasitic divisions, including Protozoa, Nematoda, and Platyhelminthes. Individual parasitic divisions are often associated with particular rheumatic syndromes, such as reactive arthritis and spondyloarthropathy, inflammatory or infectious myositis, and reactive or parainfectious vasculitis.

CONCLUSIONS AND RELEVANCE

Parasitic infection may underlie the clinical presentation of some rheumatic conditions. Given the continued and growing number of patients at risk for parasitosis by virtue of their country of origin, travel habits, and an immunocompromised state, potential parasitosis must be considered in patients undergoing evaluation for rheumatic complaints.

Trichinosis

Preview The incidence of many infectious diseases has declined as a result of modern sanitation, disease surveillance programs, and other public health measures. Trichinosis, however, continues to occur at a frequency that merits awareness by physicians. Dr Stack describes a case linked to homemade pork sausage and reviews current factors in epidemiology, diagnosis, and treatment of this uncommon but still troublesome disease.

Rheumatic syndromes associated with parasites

A variety of musculoskeletal syndromes has been described in association with numerous parasitic infestations. Arthritis, enthesitis, myositis and vasculitis have been described in infected individuals resident in, or visitors to, endemic areas. The diagnosis of parasitic rheumatism is supported by poor response to anti-inflammatory drugs and improvement following antiparasitic treatment.

[Periarteritis nodosa and parvovirus B19 infection]

The authors report a case of polyarteritis nodosa which coincide with serological conversion to parvovirus B19. After review of the literature, they recall the role of this virus in human pathology and also the role of different infectious agents in the PAN pathogenesis.

Randomized trial of albendazole versus tiabendazole plus flubendazole during an outbreak of human trichinellosis

To determine the therapeutic usefulness of benzimidazoles in trichinellosis, 117 patients from a single outbreak were treated either with albendazole alone (N = 59) or with a regimen including tiabendazole followed by flubendazole (N = 58). The criteria of disease activity were evaluated at days 1, 7, 15, and 45. No difference was found between the two groups with regard to the evolution of myalgia, fever, fatigue, new clinical manifestations, or laboratory and serologic data. Both treatment regimens were well tolerated. In all, 30 patients of the albendazole group and 29 of the tiabendazole-flubendazole group were reevaluated 16 months later. Serology was negative in 70% of the albendazole-treated patients vs 34.5% of the tiabendazole-flubendazole-treated patients (P less than 0.01). The muscle biopsy examination of nine patients suggested less parasitic infection in the albendazole group. In conclusion, no difference was noted during the early therapeutic responses to the drugs used, but albendazole might be more effective than the other regimen in treating residual larval infestation estimated 16 months after the onset of the disease.

Pathogenesis of rheumatoid arthritis: a vascular hypothesis

Past research into the pathogenesis of RA has generally concerned itself with established inflammation. The present review summarizes alterations in microvascular anatomy and function which occur during the hypoxic state, in various experimental and disease conditions. It further shows that tissue hypoxia is a common finding in RA and that the microvascular alterations of RA are similar to those produced by experimental hypoxia. The available data suggest that microcirculatory compromise, concomitant with an increase in metabolic needs of synovial tissue, may initiate tissue injury via anoxia and acidosis, resulting in hydrolytic enzyme release, increased vascular permeability and acceleration of inflammatory processes. It is further believed that the microcirculatory abnormality may be generalized, accounting for the systemic manifestations often seen in RA. Factors effecting arteriolar blood flow obstruction are reviewed to identify areas for future investigation in RA and other disorders involving microvasculopathy. The multitude of longknown and newly recognized factors predisposing to vasospasm and vasodilatation have been outlined as a guide to possible mechanisms which may be operative in RA. An attempt has been made to gather and synthesize the available data in the hope that it may stimulate other investigators to pursue more definitive research into specific areas which may show early microvascular abnormalities in the pathophysiology of RA. Identification of factors operative early in the pathogenesis of RA, before it becomes self-perpetuating, may well be a step in the direction of preventing the ravages of this disease, or providing insight to more effective control.