First record of a new microsporidium pathogenic to Gonipterus platensis in Brazil.

Microsporidia are naturally occurring fungal-related parasites that can infect nearly all animal hosts, but their biocontrol potential of insect pests is routinely overlooked in agriculture and forestry. This research brings the first report describing the natural occurrence of a microsporidium causing disease in field-collected populations of the invasive eucalyptus snout beetle, Gonipterus platensis (Coleoptera: Curculionidae), a major destructive pest of eucalyptus plantations in Brazil. Adult beetles were collected during field surveys in commercial eucalyptus plantations in southern Brazil to be examined and dissected with typical symptoms to verify presence of microsporidian spores in haemolymph. From 14 plantations in different sites, the natural infection occurrence in these populations ranged from 0 to 65%, while a lab colony exhibited an infection incidence of 70%. Spore density in haemolymph of symptomatic insects averaged 2.1 (± 0.4) × 107 spores/beetle. Symptoms in infected adults were identified by an abnormal abdomen with malformation of the second pair of wings, impairing their flight activity. Electron transmission microscopy of the pathogen showed morphological features similar to species belonging to the genus Nosema or Vairimorpha. Phylogenetic analysis of the full-length small subunit ribosomal RNA gene suggests this pathogen's placement in the genus Vairimorpha, but with a sequence identity of ~ 94% with the nearest neighbours. The low level of sequence identity suggests this pathogen may represent a novel taxon in the genus and further requires whole genome sequencing for definitive taxonomic resolution. These findings provide insights on the natural occurrence of this novel pathogen of this invasive pest in Eucalyptus plantations in Brazil. Further studies are needed to determine potential of this microsporidium in the design of conservative or augmentative biological control programs for this invasive pest.

Molecular identification of microsporidian species in patients with epithelial keratitis.

Introduction. Ocular microsporidiosis is a significant emerging infectious disease reported in immunocompromised patients and immunocompetent persons throughout the world.Aim. To identify the pathogens responsible for human keratitis, via corneal scrapings.Methodology. Thirty-three hospitalized patients with epithelial keratitis were examined using staining and DNA sequencing. DNA was extracted from corneal samples and the small-subunit ribosomal RNA gene was amplified by polymerase chain reaction (PCR) and sequenced.Results. Twenty-one samples were positive by staining while PCR generated amplicons in 18 cases. Of the 18 sequences, 16 were identical with, or very similar to, those of Vittaforma corneae (99-100 % similarity) and the remaining two sequences were similar to that of unidentified Microsporidium species deposited in the GenBank.Conclusion. This study has reconfirmed that V. corneae causes epithelial keratitis in humans and that a newly detected Microsporidium species is also involved in microsporidial keratitis as one of the emerging pathogens in Thailand. Ophthalomologists should be aware of microsporidial keratitis in people from Thailand and those from neighbouring countries.

Ultrastructure, molecular phylogeny, and prevalence rates of Alternosema bostrichidis gen. nov. sp. nov. (Microsporidia, Terresporidia), a parasite of Prostephanus truncatus and Dinoderus spp. (Coleoptera, Bostrichidae).

A new species and a new genus of a microsporidium Alternosema bostrichidis isolated from an adult Prostephanus truncatus in Mexico and from three species of the genus Dinoderus in Nigeria are described. The microsporidium is monomorphic, monoxenic, and develops in direct contact with host cell cytoplasm. The infection first appears with thoracic muscles, followed by a generalized invasion of the host. All developmental stages are diplokaryotic. Sporogony is disporoblastic. Mature spores are ovoid. Unfixed spores measure 3.7-4.2 × 2.0-2.6 µm, fixed and stained spores 3.5-5.0 × 2.4-2.8 µm. The polaroplast consists of dense lamellae and rare lamellae. The polar tube is slightly anisofilar, consisting of 11-17 coils, with 9-14 proximal (130 nm in diameter) and 2-3 distal coils (120 nm in diameter) arranged in one layer. Molecular phylogenetic analysis based upon a short portion of small-subunit ribosomal RNA gene (Genbank accession # KP455651) placed the new microsporidium within Liebermannia-Orthosomella lineage, which contains multiple undescribed parasites. In particular, A. bostrichidis showed maximal sequence similarity of 95% to Microsporidium sp. BBRE2 (# FJ755987) from Baikalian Diplacanthus brevispinus (Amphipoda: Acanthogammaridae) and Microsporidium sp. Comp CD Van 2 (# KC111784) from compost and soil in Canada. Frequent, devastating epizootics of laboratory cultures of A. bostrichidis support its potential as a biological control agent of grain borers.

A Vavraia-like microsporidium as the cause of deadly infection in threatened and endangered Eurycea salamanders in the United States.

BACKGROUND: Eurycea sosorum (Barton Springs salamander) and Eurycea nana (San Macros salamander) are listed as endangered and threatened species, respectively, by the U.S. Fish and Wildlife Service (USFWS) with habitats restricted to small regions near Austin, Texas, USA. The conservation efforts with the Eurycea salamanders at the captive breeding program in San Marcos Aquatic Resources Center (SMARC), a USFWS facility, have seen an unexpected and increased mortality rate over the past few years. The clinical signs of sick or dead salamanders included erythema, tail loss, asymmetric gills or brachial loss, rhabdomyolysis, kyphosis, and behavior changes, suggesting that an infectious disease might be the culprit. This study aimed to identify the cause of the infection, determine the taxonomic position of the pathogen, and investigate the potential reservoirs of the pathogen in the environment. RESULTS: Histopathological examination indicated microsporidian infection (microsporidiosis) in the sick and dead Eurycea salamanders that was later confirmed by PCR detection. We also determined the near full-length small subunit ribosomal RNA (SSU rRNA) gene from the microsporidian pathogen, which allowed us to determine its phylogenetic position, and to design primers for specific and sensitive detection of the pathogen. Phylogenetic analysis indicated that this pathogen was closely related to the insect parasites Vavraia spp. and the human opportunistic pathogen, Trachipleistophora hominis. This Vavraia-like microsporidium was present in dead salamanders at SMARC archived between 2011 and 2015 (positive rates ranging between 52.0-88.9% by PCR detection), as well as in some aquatic invertebrates at the facility (e.g. snails and small crustaceans). CONCLUSIONS: A Vavraia-like microsporidian was at least one of the major pathogens, if not solely, responsible for the sickness and mortality in the SMARC salamanders, and the pathogen had been present in the center for years. Environmental invertebrates likely served as a source and reservoir of the microsporidian pathogen. These observations provide new knowledge and a foundation for future conservation efforts for Eurycea salamanders including molecular surveys, monitoring of the pathogen, and discovery of effective treatments.

A Microsporidian Infection in Phoronids (Phylum Phoronida): Microsporidium phoronidi n. sp. from a Phoronis embryolabi.

Microsporidia-like spores (2.0-3.0 × 1.3-1.5 µm) were discovered upon examination of histological sections taken from Phoronis embryolabi Temereva, Chichvarkhin 2017 found inhabiting burrows of shrimps Nihonotrypeae japonica (Decapoda, Callianassidae) from the Sea of Japan, Russia. Ultrastructural examination of spores revealed one nucleus and a uniform polar filament of 7-11 coils. Representatives of the phylum Phoronida have never been recorded as hosts of microsporidia. Parasites developed in vasoperitoneal tissue and caused formation of multinucleate syncytia. Basing on unique host and fine morphology, we assign the novel finding to Microsporidium phoronidi n. sp. and place provisionally in the collective genus Microsporidium.

Description and phylogeny of a new microsporidium from the elm leaf beetle, Xanthogaleruca luteola Muller, 1766 (Coleoptera: Chrysomelidae).

This study describes a new genus and species of microsporidia which is a pathogen of the elm leaf beetle, Xanthogaleruca luteola Muller, 1776 (Coleoptera: Chrysomelidae). The beetles were collected from Istanbul in Turkey. All developmental stages are uninucleate and in direct contact with the host cell cytoplasm. Giemsa-stained mature spores are oval in shape and measured 3.40 ± 0.37 µm in length and 1.63 ± 0.20 µm in width. These uninucleate spores have an isofilar polar filament with 11 turns. The spore wall was trilaminar (75 to 115 nm) with a rugose, electron-dense exospore (34 to 45 nm) and a thickened, electron-lucent endospore (65 to 80 nm) overlaying the plasmalemma. Morphological, ultrastructural, and molecular features indicate that the described microsporidium is dissimilar to all known microsporidian taxa and confirm that it has different taxonomic characters than other microsporidia infecting X. luteola and is named here as Rugispora istanbulensis n. gen., n. sp.

[The water supply of a pediatric hospital as a possible source of an outbreak of diarrhea due to Microsporidium spp. in immunocompromised patients]. / Agua potable como posible fuente de brote de diarrea por Microsporidium spp. en pacientes inmunocomprometidos en un hospital pediátrico.

INTRODUCTION: The hospital water supply is a reservoir of a variety of potentially pathogenic microorganisms that can particularly affect children and immunocompromised patients. Potentially pathogenic Microsporidium spp. have been identified in water. Microsporidiosis is an emerging parasitic and opportunistic infection in immunocompromised patients. OBJECTIVE AND METHOD: to describe an outbreak of nosocomial diarrhea due to Microsporidium, species Encephalitozoon intestinalis. RESULTS: Seven cases of E. intestinalis associated diarrhea were reported between november 2012 and february 2013, in a unit of immunocompromised patients in L. Calvo Mackenna Children's Hospital. Microsporidium spp. was found in the hospital water supply and water reservoir tank. Secondary cases were transmitted by contact. Control measures included contact precautions, not to use faucet water for hand washing, bottled water for drinking and water reservoir tank sanitation. CONCLUSIONS: This research is about a nosocomial outbreak associated with water supply. Water quality in Chilean hospitals is an unresolved issue, especially in immunocompromised patient areas. Compliance of cleaning and disinfection of water supply systems in hospitals must be ensured.

Agua potable como posible fuente de brote de diarrea por Microsporidium spp. en pacientes inmunocomprometidos en un hospital pediátrico / The water supply of a pediatric hospital as a possible source of an outbreak of diarrhea due to Microsporidium spp. in immunocompromised patients

Introduction: The hospital water supply is a reservoir of a variety of potentially pathogenic microorganisms that can particularly affect children and immunocompromised patients. Potentially pathogenic Microsporidium spp. have been identified in water. Microsporidiosis is an emerging parasitic and opportunistic infection in immunocompromised patients. Objective and Method: to describe an outbreak of nosocomial diarrhea due to Microsporidium, species Encephalitozoon intestinalis. Results: Seven cases of E. intestinalis associated diarrhea were reported between november 2012 and february 2013, in a unit of immunocompromised patients in L. Calvo Mackenna Children's Hospital. Microsporidium spp. was found in the hospital water supply and water reservoir tank. Secondary cases were transmitted by contact. Control measures included contact precautions, not to use faucet water for hand washing, bottled water for drinking and water reservoir tank sanitation. Conclusions: This research is about a nosocomial outbreak associated with water supply. Water quality in Chilean hospitals is an unresolved issue, especially in immunocompromised patient areas. Compliance of cleaning and disinfection of water supply systems in hospitals must be ensured.

Introducción: Los sistemas de suministro de agua potable de los hospitales constituyen un reservorio de una variedad de microorganismos potencialmente patógenos que pueden afectar especialmente a niños y pacientes inmunocomprometidos. Especies de Microsporidium spp. potencialmente patógenos para el hombre han sido identificadas en el agua potable. La microsporidiosis es una infección parasitaria oportunista en pacientes inmunocomprometidos. Objetivos y Método: Describir un brote de diarrea nosocomial por Microsporidium de la especie Encephalitozoon intestinalis. Resultados: Se registraron siete casos de diarrea por E. intestinalis, entre noviembre de 2012 y febrero de 2013, en una unidad de pacientes inmunocomprometidos del Hospital de Niños Luis Calvo Mackenna, comprobándose la presencia de Microsporidium spp. abundante en el agua potable y estanques del hospital. Los casos secundarios pudieron transmitirse por contacto. Las medidas de control fueron precauciones de contacto, no usar agua de grifos para lavado de manos, ingesta de agua envasada y desinfección de estanques. Conclusiones: Esta investigación corresponde a un brote nosocomial transmitido por agua potable. La importancia de la calidad del agua en los hospitales de nuestro país es un tema no resuelto, especialmente en áreas que atienden pacientes inmunocomprometidos. Debe asegurarse el cumplimiento de limpieza y desinfección de los sistemas de suministro de agua en los hospitales.

Occurrence of Microsporidium sp. and other pathogens in Ips amitinus (Coleoptera: Curculionidae).

A new microsporidium is reported from the small spruce bark beetle, Ips amitinus: Microsporidium sp. with uninucleate oval spores measuring 3.5 × 2.5 µm; infecting cells of the midgut epithelium, midgut muscles, the fat body, the Malpighian tubules, and the gonads of adult beetles collected in Austria. Seven other pathogens were found in beetles collected from Austria, the Czech Republic, and Finland. Six of them were already known from I. amitinus. Nosema cf. typographi is recorded for the first time in the overwintering generation of I. amitinus from the Czech Republic.

Ultrastructural characterization of Acarispora falculifera n.gen., n.sp., a new microsporidium (Opisthokonta: Chytridiopsida) from the feather mite Falculifer rostratus (Astigmata: Pterolichoidea).

Only about 20 species of microsporidia have been described from mites. All except one species produce typical spores with a long polar filament and a polaroplast. This paper is the first study of an atypical microsporidium infection in a feather mite (Falculifer rostratus). The infection of the pigeon feather mite is restricted to the colon epithelium where it leads to hypertrophy of the concerned cells. During sporogony, a multinucleate plasmodial aggregate is formed within a sporont (endogenous sporogony resulting in a polysporophorous vesicle). The cisterns delimiting the single sporoblasts later form the spore walls. Sporogonial stages are in direct contact to the host cell cytoplasm. Merogonial stages were not present. Spores are tiny (3.6 µm × 2.6 µm), broad oval in form and monokaryotic. The spore wall of mature spores consists of a three-layered endospore and a thin, electron-dense, wavy exospore. The polar filament is anisofilar and completely coiled in 3-4 turns. In cross-sections, it has a star-like appearance because the electron-dense core forms rounded compartments of lucent material at its surface. In superficial sections, this results in a honeycomb-like pattern. A polaroplast is missing. The polar filament arises subapically at a polar sac that lacks an internal anchoring disk. These atypical spore structures clearly classify the species from the feather mite as a member of the order Chytridiopsida. It could not be clearly affiliated to one of the known genera, so we created a new genus, Acarispora, with the species A. falculifera.

Tubulinosema pampeana sp. n. (Microsporidia, Tubulinosematidae), a pathogen of the South American bumble bee Bombus atratus.

An undescribed microsporidium was detected and isolated from the South American bumble bee Bombus atratus collected in the Pampas region of Argentina. Infection intensity in workers averaged 8.2 × 10(7)spores/bee. The main site of infection was adipose tissue where hypertrophy of adipocytes resulted in cyst-like body formation. Mature spores were ovoid and monomorphic. They measured 4.00 µm × 2.37 µm (fresh) or 3.98 µm × 1.88 µm (fixed). All stages were diplokariotic and developed in direct contact with host cytoplasm. Isofilar polar filament was arranged in 16 coils in one or, posteriorly, two layers. Coiling angle was variable, between perpendicular and almost parallel to major spore axis. Late meronts and sporogonial stages were surrounded by vesicles of approximately 60 nm in diameter. Based on both new and already designed primers, a 1827 bp (SSUrRNA, ITS, LSUrRNA) sequence was obtained. Data analyses suggest that this microsporidium is a new species of the genus Tubulinosema. The name Tubulinosema pampeana sp. n. is proposed.

Morphology and phylogeny of Agmasoma penaei (Microsporidia) from the type host, Litopenaeus setiferus, and the type locality, Louisiana, USA.

Since June 2012, samples of wild caught white shrimp, Litopenaeus setiferus, from the Gulf of Mexico, Plaquemines and Jefferson Parishes (Louisiana, USA) with clinical signs of microsporidiosis have been delivered to the Louisiana Aquatic Diagnostic Laboratory for identification. Infection was limited predominantly to female gonads and was caused by a microsporidium producing roundish pansporoblasts with eight spores (3.6×2.1 µm) and an anisofilar (2-3+4-6) polar filament. These features allowed identification of the microsporidium as Agmasoma penaei Sprague, 1950. Agmasoma penaei is known as a microsporidium with world-wide distribution, causing devastating epizootic disease among wild and cultured shrimps. This paper provides molecular and morphological characterisation of A. penaei from the type host and type locality. Comparison of the novel ssrDNA sequence of A. penaei from Louisiana, USA with that of A. penaei from Thailand revealed 95% similarity, which suggests these geographical isolates are two different species. The A. penaei sequences did not show significant homology to any other examined taxon. Phylogenetic reconstructions using the ssrDNA and alpha- and beta-tubulin sequences supported its affiliation with the Clade IV Terresporidia sensu Vossbrink 2005, and its association with parasites of fresh and salt water crustaceans of the genera Artemia, Daphnia and Cyclops.

Morphological and phylogenetic description of a new xenoma-inducing microsporidian, Microsporidium aurata nov. sp., parasite of the gilthead seabream Sparus aurata from the Red Sea.

A new species of Microsporidia found in the marine teleost Sparus aurata collected from Hurghada coasts along the Red Sea, Egypt was described based on light and ultrastructural studies. Twenty three (30.6%) out of 75 of the examined fish were parasitized with a microsporidian parasite. Numerous macroscopic whitish cysts embedded in the peritoneal cavity were observed to infect many organs of the body including muscles, connective tissues, and the intestinal epithelium. The infection was developed as tumor-like masses of often up to 5 mm in diameter inducing an enormous hypertrophy to the infected organs. Fresh spores appeared mostly ovoid to pyriform in shape reaching a size of 1.7 ± 0.5 (1.5-2.5) µm × 1.3 ± 0.4 (1-2) µm; they possessed a large vacuole at the posterior end. These spores were located within a sporophorous vesicle which was bound by a thick amorphous wall. The ultrastructural features support the placement of the present species within the genus Microsporidium. The developmental stages were enclosed within a xenoma structure that was bounded by a double-layered cyst wall. The life cycle of the microsporidian pathogen described herein included four stages: proliferation (merogony), sporogony, sporoblast, spores, and liberation. Mature spores appeared electron dense, uninucleate, and were ellipsoidal in shape. At the anterior end of the spore, the anchoring disk was found in a central position. There was a definite number (5-11) of turns of the polar tube. A 538-bp region of the SSU rDNA gene of the studied species was sequenced (GenBank accession number: KF0220444). Multiple sequence alignment calculated a high degree of similarity (>92%) with six microsporidian species. The most closely related sequence was provided by the GenBank entry AF151529 for Microsporidium prosopium isolated from Hyperoplus lanceolatus differing in 67 nucleotide positions in its SSU rDNA with the highest percentage of identity (97.2%) and the lowest divergence value (0.20). Variations in the morphology of the spores and developmental stages between the two species revealed that the two species are different. The site of infection in the host and description of the onset of parasite development are strong criteria for the placement of the microsporidian parasite of the fish S. aurata within the genus Microsporidium as a new species, and we propose to name it Microsporidium aurata nov. sp.

Disseminated infection caused by novel species of Microsporidium, Thailand.

We describe a case of microsporidial myositis in a healthy man from Thailand. The small subunit rRNA sequence of this microsporidium is novel and has a close phylogenetic relationship with Endoreticulatus, a genus of lepidopteran microsporidia. Myositis could be caused by more genera of microsporidia than previously known.

Development, ultrastructural pathology, and taxonomic revision of the Microsporidial genus, Pseudoloma and its type species Pseudoloma neurophilia, in skeletal muscle and nervous tissue of experimentally infected zebrafish Danio rerio.

The microsporidium Pseudoloma neurophilia was initially reported to infect the central nervous system of zebrafish causing lordosis and eventually death. Subsequently, muscle tissue infections were also identified. To understand the infection process, development, and ultrastructural pathology of this microsporidium, larval and adult zebrafish were fed P. neurophilia spores. Spores were detected in the larval fish digestive tract 3-h postexposure (PE). By 4.5-d PE, developing parasite stages were identified in muscle tissue. Wet preparations of larvae collected at 8-d PE showed aggregates of spores in the spinal cord adjacent to the notochord. All parasite stages, including spores, were present in the musculature of larval fish 8-d PE. Adult zebrafish sacrificed 45-d PE had fully developed infections in nerves. Ultrastructural study of the developmental cycle of P. neurophilia revealed that proliferative stages undergo karyokinesis, producing tetranucleate stages that then divide into uninucleate cells. The plasmalemma of proliferative cells has a previously unreported glycocalyx-like coat that interfaces with the host cell cytoplasm. Sporogonic stages form sporophorous vacuoles (SPOV) derived from the plasmalemmal dense surface coat, which "blisters" off sporonts. Uninucleate sporoblasts and spores develop in the SPOV. The developmental cycle is identical in both nerve and muscle. The SPOV surface is relatively thick and is the outermost parasite surface entity; thus, xenomas are not formed. Based on the new information provided by this study, the taxonomic description of the genus Pseudoloma and its type species, P. neurophilia, is modified and its life cycle described.

Ultrastructure and molecular phylogenetics of Helmichia lacustris, a microsporidium with an uncoiled isofilar polar filament.

The description of Helmichia lacustris Voronin (Parazitologiya 34:327-331 1998) is supplemented with morphogenesis and ultrastructure of the extrusion apparatus. Formation of the anterior (made up by rare short lamellae) and posterior (made up by spongy matter or small vesicles) regions of the polaroplast is preceded by granulated spheres and agglomerations of bean-like bodies, respectively. The anchoring disc is formed by an oval structure of moderate electron density, sometimes possessing a granular texture. The parasite development occurs within the cisterns of granular endoplasmatic reticulum (ER) of the host cell. Each group of spores is enclosed within a two-layered sheath, including the smooth inner membrane of the sporophorous vesicle and the outer ribosome-encrusted membrane (which originates from the host cell ER) of the parasitophorous vacuole. Two microsporidia, H. lacustris (GenBank accession number GU130406) and Euplotespora binucleata (GenBank accession number DQ675604) share 78.1% of 16S rRNA gene sequence similarity. Both parasites are characterized by an uncoiled isofilar polar filament. They form a cluster nested among terrestrial and aquatic microsporidia with well-developed coiled polar filaments, suggesting that an uncoiled polar filament in this species is a result of reduction, rather than a "primitive" character.

Encephalomyelitis associated with microsporidian infection in farmed greater amberjack, Seriola dumerili (Risso).

An outbreak of a disease characterized by a peculiar spiral movement in farmed greater amberjack, Seriola dumerili (Risso), occurred in Kagoshima Prefecture, Japan, in May 2008, immediately after importing the fish from China. Although neither bacteria nor viruses were detected in routine diagnostic tests, histopathological observations of the affected fish revealed severe inflammation in the tegmentum of the brain including the medulla oblongata and the anterior part of the spinal cord. In addition, a microsporidian parasite was observed in the nerve cell bodies or axons in the inflamed tissues. We identified a microsporidian small subunit rRNA gene (SSU rDNA) from the lesion, and the sequence showed 96.1% identity with that of Spraguea lophii. Subsequent in situ hybridization using probes presumably specific to the SSU rRNA confirmed that the parasite observed in histopathology harboured the identified SSU rRNA. Apparently degenerated microsporidian cells or spores were also frequently observed in tissue sections. Thus, the disease was most probably caused by the infection of a hitherto unknown microsporidian parasite that has a genetic affinity to the genus Spraguea, in the central nervous system of the amberjack.

Microsporidial stromal keratitis successfully treated with medical therapy: a case report.

PURPOSE: To report a case of stromal microsporidiosis that responded to medical treatment with systemic albendazole and topical chlorhexidine. METHODS: A 14-year-old adolescent girl presented with a 3-month history of recurrent redness, pain, and dense anterior stromal corneal infiltrate. Repeated microbiological evaluation helped identify microsporidia from the fifth scraping. Initial therapy with fluoroquinolones failed; 0.02% topical chlorhexidine gluconate hourly and 400 mg of oral albendazole twice daily and later 0.5% loteprednol etabonate were given for a total of 12 weeks. RESULTS: There was complete resolution of the infection with corneal scarring with no episodes of recurrence at 1 year of follow-up. The final best-corrected visual acuity was 20/30. CONCLUSIONS: The diagnosis of microsporidia can be challenging, and corneal scraping should be repeated several times in cases having a high index of suspicion. Medical therapy can prove successful in selected cases where the infection may be limited to midstroma.

Emerging microsporidian infections in Russian HIV-infected patients.

Microsporidia were identified in stool specimens by histochemistry and PCR of 30 (18.9%) of 159 HIV-infected patients presenting to the S. P. Botkin Memorial Clinical Hospital of Infectious Diseases, St. Petersburg, Russia. The higher prevalence of Encephalitozoon intestinalis, in 21 (12.8%) patients, than of Enterocytozoon bieneusi, in 2 patients (1.2%), was unexpected. Encephalitozoon cuniculi was detected in three patients: one with strain I and two with strain II. Encephalitozoon hellem was detected in one patient, and two patients were identified as being infected by Microsporidium species. One patient was infected with both E. intestinalis and E. cuniculi. In two patients, the microsporidian species were not identifiable. No statistically significant differences in gender, age, and stage of AIDS were observed between the microsporidian-positive and -negative HIV-infected patients. HIV-infected patients diagnosed with microsporidian infection, however, were significantly more likely to exhibit ≤ 100 CD4(+) T cells/µl blood (20/30 patients [67%]; odds ratio [OR], 3.150; 95% confidence interval [CI(95)], 1.280 to 7.750; P = 0.0116) and weight loss of >10% of the baseline (19/30 patients [63%]; odds ratio, 2.995; CI(95), 1.100 to 8.158; P = 0.0352) than HIV-infected patients not diagnosed with microsporidian infection. In summary, this is the first report describing the diagnosis of microsporidian infection of HIV-infected patients in Russia and the first detection of E. cuniculi strain II in a human.

Evaluation of gram-chromotrope kinyoun staining technique: its effectiveness in detecting microsporidial spores in fecal specimens.

This study was conducted to evaluate the modification of the usual Gram-chromotrope staining technique developed in-house known as Gram-chromotrope Kinyoun (GCK) in comparison with the Weber Modified Trichrome (WMT) staining technique; as the reference technique. Two hundred and ninety fecal specimens received by the Microbiology Diagnostic Laboratory of Hospital Universiti Kebangsaan Malaysia were examined for the presence of microsporidial spores. The sensitivity and specificity of GCK compared to the reference technique were 98% and 98.3%, respectively. The positive and negative predictive values were 92.5% and 99.6%, respectively. The agreement between the reference technique and the GCK staining technique was statistically significant by Kappa statistics (K = 0.941, P < 0.001). It is concluded that the GCK staining technique has high sensitivity and specificity in the detection of microsporidial spores in fecal specimens. Hence, it is recommended to be used in the diagnosis of intestinal microsporidiosis.