Practical Guidance for Clinical Microbiology Laboratories: Laboratory Diagnosis of Parasites from the Gastrointestinal Tract.

This Practical Guidance for Clinical Microbiology document on the laboratory diagnosis of parasites from the gastrointestinal tract provides practical information for the recovery and identification of relevant human parasites. The document is based on a comprehensive literature review and expert consensus on relevant diagnostic methods. However, it does not include didactic information on human parasite life cycles, organism morphology, clinical disease, pathogenesis, treatment, or epidemiology and prevention.

Production and characterization of monoclonal antibodies against Encephalitozoon intestinalis and Encephalitozoon sp. spores and their developmental stages.

Background: Microsporidia are intracellular obligate parasites traditionally associated with immunosuppressed patients; their detection in immunocompetent patients has increased, highlighting their possible importance as emerging pathogens. Detection of spores in stools, urine, body fluids and tissues is difficult and immunological techniques such as immunofluorescence have proved to be a useful and reliable tool in the diagnosis of human microsporidiosis. For this reason, we have produced and characterized monoclonal antibodies (MAbs) specific for Encephalitozoon intestinalis (the second most frequent microsporidian infecting humans), and other Encephalitozoon species, that can be used in different diagnostic techniques.

Three Cases of Neurologic Syndrome Caused by Donor-Derived Microsporidiosis.

In April 2014, a kidney transplant recipient in the United States experienced headache, diplopia, and confusion, followed by neurologic decline and death. An investigation to evaluate the possibility of donor-derived infection determined that 3 patients had received 4 organs (kidney, liver, heart/kidney) from the same donor. The liver recipient experienced tremor and gait instability; the heart/kidney and contralateral kidney recipients were hospitalized with encephalitis.

Transmission of Balamuthia mandrillaris by Organ Transplantation.

Background: During 2009 and 2010, 2 clusters of organ transplant-transmitted Balamuthia mandrillaris, a free-living ameba, were detected by recognition of severe unexpected illness in multiple recipients from the same donor.

Methods: We investigated all recipients and the 2 donors through interview, medical record review, and testing of available specimens retrospectively. Surviving recipients were tested and treated prospectively.

Use of the Novel Therapeutic Agent Miltefosine for the Treatment of Primary Amebic Meningoencephalitis: Report of 1 Fatal and 1 Surviving Case.

Primary amebic meningoencephalitis (PAM) is a fulminant central nervous system infection caused by the thermophilic free-living ameba Naegleria fowleri. Few survivals have been documented and adequate treatment is lacking. We report 2 PAM cases, 1 fatal and 1 surviving, treated with the novel antiparasitic agent miltefosine.

Diagnosis, Clinical Course, and Treatment of Primary Amoebic Meningoencephalitis in the United States, 1937-2013.

Background: Primary amoebic meningoencephalitis (PAM) is a rapidly progressing waterborne illness that predominately affects children and is nearly always fatal. PAM is caused by Naegleria fowleri, a free-living amoeba found in bodies of warm freshwater worldwide.

Methods: We reviewed exposure location, clinical signs and symptoms, diagnostic modalities, and treatment from confirmed cases of PAM diagnosed in the United States during 1937-2013.

Malignant Transformation of Hymenolepis nana in a Human Host.

Neoplasms occur naturally in invertebrates but are not known to develop in tapeworms. We observed nests of monomorphic, undifferentiated cells in samples from lymph-node and lung biopsies in a man infected with the human immunodeficiency virus (HIV). The morphologic features and invasive behavior of the cells were characteristic of cancer, but their small size suggested a nonhuman origin.

Assessment of blood-brain barrier penetration of miltefosine used to treat a fatal case of granulomatous amebic encephalitis possibly caused by an unusual Balamuthia mandrillaris strain.

Balamuthia mandrillaris, a free-living ameba, causes rare but frequently fatal granulomatous amebic encephalitis (GAE). Few patients have survived after receiving experimental drug combinations, with or without brain lesion excisions. Some GAE survivors have been treated with a multi-drug regimen including miltefosine, an investigational anti-leishmanial agent with in vitro amebacidal activity.

Disseminated Balamuthia mandrillaris Infection.

Balamuthia mandrillaris is a rare cause of human infection, but when infections do occur, they result in high rates of morbidity and mortality. A case of disseminated Balamuthia infection is presented. Early diagnosis and initiation of recommended therapy are essential for increased chances of successful outcomes.

In vitro growth, cytopathic effects and clearance of monolayers by clinical isolates of Balamuthia mandrillaris in human skin cell cultures.

Balamuthia mandrillaris is a free-living ameba (FLA) that has been isolated or its DNA identified in soil, dust and water. It causes a fatal central nervous system infection in humans and animals. Although it is environmental as Acanthamoeba and Naegleria fowleri, the two other free-living amebae that also cause CNS infections in humans and other animals, Balamuthia does not feed on bacteria as the other FLA.

Identification of Giardia duodenalis and Enterocytozoon bieneusi in an epizoological investigation of a laboratory colony of prairie dogs, Cynomys ludovicianus.

Since 2005, black-tailed prairie dogs (Cynomys ludovicianus) have been collected for use as research animals from field sites in Kansas, Colorado, and Texas. In January of 2012, Giardia trophozoites were identified by histology, thin-section electron microscopy, and immunofluorescent staining in the lumen of the small intestine and colon of a prairie dog euthanized because of extreme weight loss. With giardiasis suspected as the cause of weight loss, a survey of Giardia duodenalis in the laboratory colony of prairie dogs was initiated.

Successful treatment of an adolescent with Naegleria fowleri primary amebic meningoencephalitis.

Naegleria fowleri is a thermophilic, free-living ameba that causes primary amebic meningoencephalitis. The infections are nearly always fatal. We present the third well-documented survivor of this infection in North America.

Microsporidiosis acquired through solid organ transplantation: a public health investigation.

Background: Encephalitozoon cuniculi, a microsporidial species most commonly recognized as a cause of renal, respiratory, and central nervous system infections in immunosuppressed patients, was identified as the cause of a temporally associated cluster of febrile illness among 3 solid organ transplant recipients from a common donor.

Objective: To confirm the source of the illness, assess donor and recipient risk factors, and provide therapy recommendations for ill recipients.

Design: Public health investigation.

Balamuthia mandrillaris Encephalitis: Survival of a Child With Severe Meningoencephalitis and Review of the Literature.

Balamuthia mandrillaris causes granulomatous amoebic encephalitis, which is frequently fatal. There are few reports of survival in children. A 4-year-old child developed severe meningoencephalitis with multiple intracranial ring-enhancing lesions.

Serologic survey for exposure following fatal Balamuthia mandrillaris infection.

Granulomatous amebic encephalitis (GAE) from Balamuthia mandrillaris, a free-living ameba, has a case fatality rate exceeding 90% among recognized cases in the USA. In August 2010, a GAE cluster occurred following transplantation of infected organs from a previously healthy landscaper in Tucson, AZ, USA, who died from a suspected stroke. As B.

Diagnostic challenges in Balamuthia mandrillaris infections.

Balamuthia mandrillaris is an emerging cause of subacute granulomatous amebic encephalitis (GAE). The diagnosis of this infection has proven to be difficult and is usually made postmortem. Early recognition and treatment may offer some benefit.

Characterization of a new pathogenic Acanthamoeba Species, A. byersi n. sp., isolated from a human with fatal amoebic encephalitis.

Acanthamoeba spp. are free-living amoebae that are ubiquitous in natural environments. They can cause cutaneous, nasopharyngeal, and disseminated infection, leading to granulomatous amebic encephalitis (GAE) in immunocompromised individuals.

Infections with free-living amebae.

Acanthamoeba spp., Balamuthia mandrillaris, and Naegleria fowleri are mitochondria-bearing, free-living eukaryotic amebae that have been known to cause infections of the central nervous system (CNS) of humans and other animals. Several species of Acanthamoeba belonging to several different genotypes cause an insidious and chronic disease, granulomatous amebic encephalitis (GAE), principally in immunocompromised hosts including persons infected with HIV/AIDS.

Balamuthia mandrillaris: in vitro interactions with selected protozoa and algae.

Although Balamuthia mandrillaris was identified more than two decades ago as an agent of fatal granulomatous encephalitis in humans and other animals, little is known about its ecological niche, biological behavior in the environment, food preferences and predators, if any. When infecting humans or other animals, Balamuthia feeds on tissues; and in vitro culture, it feeds on mammalian cells (monkey kidney cells, human lung fibroblasts, and human microvascular endothelial cells). According to recent reports, it is believed that Balamuthia feeds on small amebae, for example, Acanthamoeba that are present in its ecological niche.

Primary amebic meningoencephalitis in Florida: a case report and epidemiological review of Florida cases.

Primary amebic meningoencephalitis (PAM) is a rare but nearly always fatal infection of the central nervous system caused by the thermophilic, free-living ameba Naegleria fowleri. Since its first description in 1965 through 2010, 118 cases have been reported in the U.S.