Dirofilaria repens in Vietnam: detection of 10 eye and subcutaneous tissue infection cases identified by morphology and molecular methods

From 2006 to 2010, hospitals in Hanoi treated 10 human patients for dirofilariasis. The worms were collected from parasitic places, and identification of the species was completed by morphology and molecular methods. Ten parasites were recovered either from the conjunctiva (n=9) or subcutaneous tissue (n=1). The parasites were 4.0-12.5 cm in length and 0.5-0.6 mm in width. Morphological observations suggested all parasites as Dirofilaria repens. Three of the 10 parasites (1 from subcutaneous tissue and 2 from eyes) were used for molecular confirmation of the species identification. A portion of the mitochondrial cox1 (461 bp) was amplified and sequenced. Nucleotide and amino acid homologies were 95% and 99-100%, respectively, when compared with D. repens (Italian origin, GenBank AJ271614; DQ358814). This is the first report of eye dirofilariasis and the second report of subcutaneous tissue dirofilariasis due to D. repens in Vietnam.     

Orbital Dirofilariasis in Iran: A Case Report

Dirofilariasis is a common parasitic disease in both domestic and wild animals around the world, with canines as the principal reservoir host and mosquitoes as the vector. Human ophthalmic dirofilariasis is an uncommon condition, but there have been reports from many parts of the world, including Africa, Australia, the Americas, Europe, and Asia. Ophthalmic involvement with Dirofilaria may present itself as periorbital, subconjunctival, orbital, or intraocular infections. In this report, we present a case of orbital dirofilariasis with lateral rectus muscle involvement. To our knowledge, this is the first orbital dirofilariasis case reported in Iran. Although debulking of the tumor usually leads to resolution, our patient showed an episode of recurrence after biopsy. Complete recovery was achieved after a spontaneous discharge, without the need for systemic medication.     

Two cases of ectopic dirofilariasis by Dirofilaria immitis in subconjunctival and subcutaneous tissues in dogs

We report two cases of ectopic dirofilariasis caused by Dirofilaria immitis in the subconjunctival and subcutaneous tissues of dogs. In Case 1, a 10-year-old female poodle suffered from a subconjunctival mass in the left eye that was refractory to antibiotic and steroid treatments. The mass was removed surgically, and a whitish nematode was identified within the mass. In Case 2, a stray 3-year-old male greyhound was rescued and transferred to a local veterinary hospital. During care, two nematodes were observed on the left hind paw and leg. The observed worms were not typical of D. immitis; therefore, the species was confirmed using molecular methods. Phylogenetic analysis revealed high genetic identity with other previously reported D. immitis strain. Subcutaneous and subconjunctival dirofilariasis have been mainly caused by D. repens. To the best of our knowledge, this is the first report of subconjunctival ectopic dirofilariasis by D. immitis in a dog, and the first report of subcutaneous localization in Korea. Therefore, in endemic regions, ectopic dirofilariasis caused by D. immitis should be considered as a differential diagnosis in subconjunctival and subcutaneous masses.     

Human pulmonary dirofilariasis: parasitological aspects of the 2d case reported in Italy]

The parasitological aspects of a case of pulmonary human dirofilariasis, recently reported by Fabbretti and collaborators (1990) in a 58 year-old man from Ferrara province, are described. This is the second case of pulmonary human dirofilariasis recorded in Italy. The nematode was rolled up inside a small pulmonary artery and was associated with a nodular infarcted lesion, discovered during an X-ray check as a "coin lesion". A pulmonary lobectomy was performed on the patient with a presumptive diagnosis of a malignant neoplastic nodule. The exact diagnosis was only made with the histological examination. In spite of the bad preservation of the nematode, it was possible to diagnose it as an immature female of Dirofilaria probably belonging to the species repens.     

Genotypic assignment of infection by Dirofilaria repens

Dirofilariasis is a parasitic disease, which if treated inappropriately due to misdiagnosis, can cause unwanted complications particularly when the infection is located in the breast. The numerous obstacles that can cause misdiagnosis of dirofilariases by standard morphological procedures prompted the development of a Dirofilaria repens-specific direct polymerase chain reaction (PCR)-based diagnostic approach using freshly infected dog blood. Reliable amplification of nematode DNA from formalin-fixed infected human specimens by this method is only possible from relatively fresh biological material, preserved in the fixative for up to 20 days. We report here our first case of dirofilariasis since the development of PCR genotyping, where the pathogen was morphologically unrecognizable and the diagnosis was based exclusively on DNA amplification. We complete our methodological contribution to the clinical laboratory diagnosis of dirofilariasis by presenting two more cases, where the primary genotypic assignment of infection by D. repens was further confirmed by conventional morphological means.     

Dirofilaria repens diagnosed by the presence of microfilariae in fine needle aspirates: a case report

BACKGROUND: Dirofilariasis due to Dirofilaria repens with viable microfilariae outside the worm have not been reported before. CASE: A 40-year-old truck driver from rural Shiraz, Iran, had a firm mass, 2.5 x 2.5 cm, at the dorsolateral aspect of the right forearm. Fine needle aspiration (FNA) was performed on 2 occasions. Several microfilariae with blunt heads, pointed posterior ends and empty caudal spaces resembling microfilariae of Wuchereria bancrofti but longer were seen. Since Iran is a nonendemic area for lymphatic filariae and the patient had a history of contact with a dog, with the impression of dirofilariasis, the mass was excised, and the presence of adult worms in tissue sections confirmed the diagnosis. CONCLUSION: This case ofsubcutaneous dirofilariasis was diagnosed by detecting microfilariae in FNA smears and was confirmed on histopathology.     

A Case of Human Pulmonary Dirofilariasis in a 48-Year-Old Korean Man

Dirofilariasis is a rare disease in humans. We report here a case of a 48-year-old male who was diagnosed with pulmonary dirofilariasis in Korea. On chest radiographs, a coin lesion of 1 cm in diameter was shown. Although it looked like a benign inflammatory nodule, malignancy could not be excluded. So, the nodule was resected by video-assisted thoracic surgery. Pathologically, chronic granulomatous inflammation composed of coagulation necrosis with rim of fibrous tissues and granulations was seen. In the center of the necrotic nodules, a degenerating parasitic organism was found. The parasite had prominent internal cuticular ridges and thick cuticle, a well-developed muscle layer, an intestinal tube, and uterine tubules. The parasite was diagnosed as an immature female worm of Dirofilaria immitis. This is the second reported case of human pulmonary dirofilariasis in Korea.     

Dirofilariasis presenting as a breast lump.

Dirofilariasis is now recognized as a zoonosis. Infection of humans occurs when a mosquito that has obtained larvae-containing blood from an infected animal transmits the larvae, after they have developed to the infective stage, to a human. Dirofilarial infections in humans have been reported from around the world. In this paper a case is reported in which subcutaneous dirofilariasis in a human presented as a lump in the breast. The epidemiologic and pathogenetic features of this disease are discussed.     

Human dirofilariasis in Italy: a new palpebral case with spontaneous healing in Abruzzo

One case of human palpebral dirofilariasis by Dirofilaria repens, in Abruzzo, is described. It is the first case reported in this region. The parasite was released following the energetic rubbing of the palpebral area, with the result in the spontaneous recovery of the patient.     

Human dirofilariasis due to Dirofilaria (Nochtiella) repens: an update of world literature from 1995 to 2000.

Following on from their review of 1995 (Pampiglione et al.), the authors present an update of human cases of dirofilariasis due to Dirofilaria (Nochtiella) repens (Nematoda, Filarioidea, Onchocercidae) reported in the world literature. Cases of the parasitosis published from 1995 to 2000 are reported country by country. The essential data are presented in tabular form and the clinical, parasitological, histopathological, epidemiological features are analysed. 372 new cases spread over 25 countries are thus added to the list published in 1995. The countries most affected are Italy, Sri Lanka, some republics of the ex-Soviet Union. The age of the patients varied from 4 months to 100 years, the majority being in their 40s. There was virtually no difference in incidence between sexes. The parasite appeared most frequently in the upper half of the body, particularly in the head and ocular region and also in the upper limbs. Cases of visceral involvement are also reported. Of the various forms of human dirofilariasis, that due to D. (N.) repens is confirmed to be the most important as regards not only the number of subjects affected and the wide geographical distribution but also the variety of organs involved, notably the lungs, the male genitals and the female breast, invariably leading to a wrong diagnosis of malignant tumour. In man, the zoonosis may be described as emerging: whereas until the middle of the last century only a few dozen cases were reported, in the last 50 years the number has gradually increased to reach the present 782.     

Pulmonary dirofilariasis diagnosed by fine needle aspiration biopsy. A case report

A case of pulmonary dirofilariasis in a 62-year-old female was diagnosed by fine needle aspiration biopsy. A review of the literature revealed this to be the first reported case diagnosed by this method. The presence of bilateral lesions in this patient is an uncommon finding for this entity.     

Par-1 regulates bicoid mRNA localisation by phosphorylating Exuperantia

The Ser/Thr kinase Par-1 is required for cell polarisation in diverse organisms such as yeast, worms, flies and mammals. During Drosophila oogenesis, Par-1 is required for several polarisation events, including localisation of the anterior determinant bicoid. To elucidate the molecular pathways triggered by Par-1, we have performed a genome-wide, high-throughput screen for Par-1 targets. Among the targets identified in this screen was Exuperantia (Exu), a mediator of bicoid mRNA localisation. We show that Exu is a phosphoprotein whose phosphorylation is dependent on Par-1 in vitro and in vivo. We identify two motifs in Exu that are phosphorylated by Par-1, and show that their mutation abolishes bicoid mRNA localisation during mid-oogenesis. Interestingly, exu mutants in which Exu phosphorylation is specifically affected can to some extent recover from these bicoid mRNA localisation defects during late oogenesis. These results demonstrate that Par-1 establishes polarity in the oocyte by activating a mediator of bicoid mRNA localisation. Furthermore, our analysis reveals two phases of Exu-dependent bicoid mRNA localisation: an early phase that is strictly dependent on Exu phosphorylation and a late phase that is less phosphorylation dependent.     

Trafficking and localisation of resident Golgi glycosylation enzymes

The localisation of glycosylation enzymes within the Golgi apparatus is fundamental to the regulation of glycoprotein and glycolipid biosynthesis. Regions responsible for specifying Golgi localisation have been identified in numerous Golgi resident enzymes. The transmembrane domain of Golgi glycosyltransferases provides a dominant localisation signal and in many cases there are also major contributions from the lumenal domain. The mechanism by which these targeting domains function in maintaining an asymmetric distribution of Golgi resident glycosylation enzymes has been intensely debated in recent years. It is now clear that the targeting of Golgi resident enzymes is intimately associated with the organisation of Golgi membranes and the control of protein and lipid traffic in both anterograde and retrograde directions. Here we discuss the recent advances into how Golgi targeting signals of glycosylation enzymes function, and propose a model for maintaining the steady-state localisation of Golgi glycosyltransferases.     

Immunodiagnosis of human dirofilariasis by enzyme-linked immunosorbent assay using recombinant DNA-derived fusion protein.

An enzyme-linked immunosorbent assay (ELISA) using antigenic beta-galactosidase-Dirofilaria immitis recombinant fusion protein (FP) obtained by the recombinant DNA technique provided a useful diagnostic tool for human dirofilariasis. D. immitis-infected human sera reacted strongly with FP that was immobilized with anti-beta-galactosidase monoclonal antibody on microplates. However, the FP did not react with sera from patients with other filariasis. In detection of anti-D. immitis IgG antibody. ELISA using FP was highly sensitive and specific compared to that using crude somatic antigen.     

Periocular Dirofilariasis in a Young Woman: A Case Report

A case of periocular dirofilariasis has been diagnosed in Iran. A 27-yr old female referred with a history of edema and redness in the left eye since 2 wk ago. On slit lamp examination, a moving thread-like worm was seen in the subconjunctival area. Two days later, a 126 mm long, live filaria worm was extracted from the lower lid subcutaneous tissue. The worm was diagnosed as, likelihood, Dirofilaria immitis on microscopic examinations. The present case suggests that D. immitis can cause periocular infections.     

Activation in vitro of some biological systems by extracts of adult worms and microfilariae of Dirofilaria immitis

Extracts of Dirofilaria immitis adults and microfilariae cause the degranulation of mast cells in rat mesentery when applied in vitro and also cause increased vascular permeability in guinea-pigs and rabbits. Adult worms but not microfilariae are able to activate complement in vitro and both stages contain a plasminogen activator. No proteolytic activity or haemolysins could be detected in either stage. The possibility that these factors may be important in the pathogenesis of dirofilariasis and in the adverse drug reactions that may follow treatment of microfilaraemic animals with diethylcarbamazine is discussed.     

Localisation and Mislocalisation of the Interferon-Inducible Immunity-Related GTPase,Irgm1 (LRG-47) in Mouse Cells

Irgm1 (LRG-47) is an interferon-inducible Golgi membrane associated GTPase of the mouse whose disruption causes susceptibility to many different intracellular pathogens. Irgm1 has been variously interpreted as a regulator of homologous effector GTPases of the IRG family, a regulator of phagosome maturation and as an initiator of autophagy in interferon-induced cells. We find that endogenous Irgm1 localises to late endosomal and lysosomal compartments in addition to the Golgi membranes. The targeting motif known to be required for Golgi localisation is surprisingly also required for endolysosomal localisation. However, unlike Golgi localisation, localisation to the endolysosomal system also requires the functional integrity of the nucleotide binding site, and thus probably reflects transient activation. Golgi localisation is lost when Irgm1 is tagged at either N- or C-termini with EGFP, while localisation to the endolysosomal system is relatively favoured. N-terminally tagged Irgm1 localises predominantly to early endosomes, while C-terminally tagged Irgm1 localises to late endosomes and lysosomes. Both these anomalous distributions are reversed by inactivation of the nucleotide binding site, and the tagged proteins both revert to Golgi membrane localisation. Irgm1 is the first IRG protein to be found associated with the endolysosomal membrane system in addition to either Golgi (Irgm1 and Irgm2) or ER (Irgm3) membranes, and we interpret the result to be in favour of a regulatory function of IRGM proteins at cellular membrane systems. In future analyses it should be borne in mind that tagging of Irgm1 leads to loss of Golgi localisation and enhanced localisation on endolysosomal membranes, probably as a result of constitutive activation.     

Human dirofilariasis in Italy: a new case in the spermatic cord

A new case of human dirofilariasis associated with Dirofilaria (Nochtiella) repens (Nematoda, Filarioidea, Onchocercidae) located in the spermatic cord is reported in a 71-year-old man from the province of Campobasso (Central Italy). When clinical signs pointed to a testicular tumor, a monolateral orchifuniculectomy was performed. According to the scientific literature, this case appears to be exceptional in its location, being only the eighth such case recorded in the world until now. The nematode, as well as the presence of vectors suitable for its transmission, had already been observed both in dogs and in humans (3 subcutaneous cases) in the same geographical area.     

Human pulmonary dirofilariasis: report of a new European case

We report a new European case of pulmonary dirofilariasis occurring in an Italian patient. The paper emphasizes the peculiar pathological features of Pulmonary Dirofilariasis, that, on clinical and radiological grounds, closely imitates primary or secondary neoplasms. The disease characteristically presents itself as a solitary subpleural coin-like lesion, histologically corresponding to a well demarcated, roughly spherical infarct, centered by a medium-sized thrombosed artery whose lumen contains the parasite, i.e. a Dirofilaria nematode.