Marked eosinophilia in an immunosuppressed patient with strongyloidiasis

Hyperinfection by Strongyloides stercoralis probably associated with Rituximab in a patient with mantle cell lymphoma and hyper eosinophilia

The first report to our knowledge, of hyperinfection by Strongyloides stercoralis (HS) and hypereosinophilia, associated to immune suppression by Rituximab (the only drug received for the last one year and 10 months), in a patient with mantle-cell lymphoma (MCL), is presented. The patient has a 3-year history of MCL, and developed two accesses of HS during 2008, including meningitis, pneumonia and presence of larvae of S. stercoralis in the lungs. We had a unique chance to look at cytotoxicity of filariform larvae in the expectoration after Ivermectin treatment, showing immobilization and death of larvae, associated with eosinophils attached to the cuticle of the parasite.

Parasites of the small intestine

This paper discusses the most important parasites that inhabit the human small intestine. Beginning with the protozoa and proceeding through the various species of cestodes, nematodes, and trematodes that inhabit the human small bowel, the most important organisms are presented. Possible future developments are discussed along with pathophysiology and treatment in this phylogenic approach. Zoonotic illnesses, those diseases that by their rarity are of little import, and diseases without significant clinical or social implications are beyond the scope of this article and are not discussed.

Parasites of the small intestine

This paper discusses the most important parasites that inhabit the human small intestine. Beginning with the protozoa and proceeding through the various species of cestodes, nematodes, and trematodes that inhabit the human small bowel, the most important organisms are presented. Possible future developments are discussed along with pathophysiology and treatment in this phylogenic approach. Zoonotic illnesses, those diseases that by their rarity are of little import, and diseases without significant clinical or social implications are beyond the scope of this article and are not discussed.

Complicated and fatal Strongyloides infection in Canadians: risk factors, diagnosis and management

Strongyloidiasis, which is caused by the nematode Strongyloides stercoralis, is a common and persistent infection, particularly in developing countries. In the setting of compromised cellular immunity, it can result in fulminant dissemination with case-fatality rates of over 70%. The majority of new Canadian immigrants come from countries where Strongyloides is highly endemic; therefore, the burden of Strongyloides may be underappreciated in Canada. Because early diagnosis and therapy can have a marked impact on disease outcome, screening for this infection should be considered mandatory for patients who have a history of travel or residence in a disease-endemic area and risk factors for disseminated disease (e.g., corticosteroid use and human T-lymphotropic virus type I infection).

Strongyloides stercoralis in the Immunocompromised Population

Strongyloides stercoralis is an intestinal nematode of humans that infects tens of millions of people worldwide. S. stercoralis is unique among intestinal nematodes in its ability to complete its life cycle within the host through an asexual autoinfective cycle, allowing the infection to persist in the host indefinitely. Under some conditions associated with immunocompromise, this autoinfective cycle can become amplified into a potentially fatal hyperinfection syndrome, characterized by increased numbers of infective filariform larvae in stool and sputum and clinical manifestations of the increased parasite burden and migration, such as gastrointestinal bleeding and respiratory distress. S. stercoralis hyperinfection is often accompanied by sepsis or meningitis with enteric organisms. Glucocorticoid treatment and human T-lymphotropic virus type 1 infection are the two conditions most specifically associated with triggering hyperinfection, but cases have been reported in association with hematologic malignancy, malnutrition, and AIDS. Anthelmintic agents such as ivermectin have been used successfully in treating the hyperinfection syndrome as well as for primary and secondary prevention of hyperinfection in patients whose exposure history and underlying condition put them at increased risk.

Epidemiology of infectious complications in cancer patients

Patients with underlying malignancies are at risk for a wide array of infectious diseases that cause significant morbidity and mortality. To develop a clear etiologic understanding of the infectious agents involved first requires a knowledge of the factors that predispose to infection. Neutropenia is clearly the single most important risk factor for infection in the cancer patient. However, a variety of both host and treatment-associated factors act together to predispose these patients to opportunistic infections. Approaching the individual malignancies with a knowledge of the underlying risk factors helps logically guide diagnosis and therapy. The astute clinician must also be aware of new and emerging infections in this patient population. As new pathogens are discovered and established pathogens become increasingly drug resistant, they will continue to present challenges for physicians caring for these patients in the years ahead.