Rapid identification of Prototheca species by the API 20C system

The Effect of Some Natural Essential Oils Against Bovine Mastitis Caused by Prototheca zopfii Isolates In Vitro

The aim of the study was to evaluate the effect of essential oils obtained from Thymus vulgaris L., Origanum vulgare L., Origanum majerana L., Mentha × piperita L. and Allium ursinum L. against Prototheca zopfii strains that cause inflammation of the udder (mastitis) in cows. The study was conducted on ten strains derived from milk samples. The microdilution method was used to determine the sensitivity of P. zopfii strains to the studied essential oils, and the disk diffusion method was used to determine the sensitivity to antifungal chemotherapeutics. The plates were incubated for 48 h at 37 °C under aerobic conditions. All strains of algae were sensitive to the essential oils marjoram, thyme and oregano and resistant to mint and garlic oils. MIC values ranged from 0.25 to 1 μl/ml. Marjoram oil demonstrated the greatest activity, and oregano oil the weakest. Among the antifungal agents tested, 90% of strains showed sensitivity to nystatin. One of the tested strains (71/IV) was resistant to all investigated antifungal agents. The tested essential oils are known to have anti-algae activity and can be used as natural agents for prophylaxis in animals, particularly in mastitis-affected cows.

Short communication: Cold atmospheric plasma inactivation of Prototheca zopfii isolated from bovine milk

Mastitis is a serious bovine diseases that can be caused by Prototheca zopfii, yeast-like algae belonging to the family Chlorellaceae. The substantial economic losses and health damage associated with bovine mastitis emphasize the need to develop effective strategies aimed at control of the infection. Unfortunately, P. zopfii is highly resistant to most common antibacterial and antifungal agents, as well as to heat treatment. We report here the first attempt to use cold atmospheric plasma to inactivate this pathogen. We studied 20 strains of P. zopfii isolated from milk samples taken from cows with clinical or subclinical mastitis. The studies confirmed the high level of resistance of P. zopfii to typical antifungal agents, such as voriconazole, fluconazole, amphotericin B, caspofungin, anidulafungin, and micafungin. In contrast, each of the strains revealed high susceptibility to cold atmospheric plasma, >2-fold higher compared with a reference strain of Candida albicans. The obtained results are promising and open up a new approach in the fight against P. zopfii.

A rapid real-time PCR/DNA resolution melting method to identify Prototheca species

AIM

The study describes the development of a simple and rapid tool to identify yeast-like microalgae belonging to the genus Prototheca.

METHODS AND RESULTS

The method, based on two-step Real Time PCR reaction followed by DNA Resolution Melting Analysis (qPCR/RMA), has been developed using reference strains belonging to both pathogenic (P. zopfii genotype 2, P. wickerhamii and P. blaschkeae) and non-pathogenic species (P. zopfii genotype 1, P. stagnora and P. ulmea). In order to validate the method, seventy recently isolated Prototheca strains were thus tested in parallel with both the first qPCR/RMA and the conventional genotype-specific PCR assay: they were classified as P. zopfii genotype 1, P. zopfii genotype 2 and P. blaschkeae, with a perfect accordance between the two above methodologies. Furthermore, we used the second qPCR/RMA to identify the other species (P. stagnora, P. ulmea and P. wickerhamii), which cannot be discriminated by conventional PCR assay.

CONCLUSIONS

The assay two-step Real Time PCR is accurate, robust, cost-effective and faster than auxonographical, biochemical or conventional molecular biology methods.

SIGNIFICANCE AND IMPACT OF THE STUDY

the rapid and high throughout two-step qPCR/RMA tool can be usefully used for the identification of clinical and environmental Prototheca species into the framework of the diagnosis of animal (e.g. bovine mastitis) or human protothecosis.

Prototecose: uma doença emergente

Prototecose, causada por Prototheca zopfii ou P. wickerhamii, é uma doença emergente em animais e humanos. Em bovinos, P. zopfii é uma importante causa de mastite ambiental. Em cães e gatos, a prototecose é causada principalmente por P. zopfii. Em cães, causa infecção cutânea ou uma forma sistêmica envolvendo diversos órgãos. Em gatos, predominam as lesões tegumentares na região da face e plano nasal. No homem, a prototecose, causada principalmente por P. wickerhamii, manifesta-se sob três formas: cutânea, articular com bursite do olécrano e sistêmica. Pode ocorrer em indivíduos imunocompetentes, os quais podem apresentar bursite e/ou infecções cutâneas localizadas, ou em indivíduos imunossuprimidos, nos quais a enfermidade pode ser disseminada e/ou com envolvimento visceral. A prototecose causada por P. wickerhamii foi descrita recentemente em caprinos como causa de rinite afetando o vestíbulo nasal, união mucocutânea, pele da face e orelha. Nesta revisão são abordadas as características microbiologias e susceptibilidade a antimicrobianos do agente, e a epidemiologia, sinais clínicos, patologia, diagnóstico, tratamento e controle da prototecose em animais domésticos e no homem.

Human protothecosis

Human protothecosis is a rare infection caused by members of the genus Prototheca. Prototheca species are generally considered to be achlorophyllic algae and are ubiquitous in nature. The occurrence of protothecosis can be local or disseminated and acute or chronic, with the latter being more common. Diseases have been classified as (i) cutaneous lesions, (ii) olecranon bursitis, or (iii) disseminated or systemic manifestations. Infections can occur in both immunocompetent and immunosuppressed patients, although more severe and disseminated infections tend to occur in immunocompromised individuals. Prototheca wickerhamii and Prototheca zopfii have been associated with human disease. Usually, treatment involves medical and surgical approaches; treatment failure is not uncommon. Antifungals such as ketoconazole, itraconazole, fluconazole, and amphotericin B are the most commonly used drugs to date. Among them, amphotericin B displays the best activity against Prototheca spp. Diagnosis is largely made upon detection of characteristic structures observed on histopathologic examination of tissue.

Meningitis due toPrototheca wickerhamii: rare case in China

A rare case of Prototheca wickerhamii meningitis is reported in a patient without any underlying immunodeficient condition. Wet-mount microscopy and culture of cerebral spinal fluid specimens, along with temperature resistance, cycloheximide tolerance, carbohydrates assimilation, including API 20C AUX tests of the isolated etiologic agent were performed. In addition, transmission and scanning electron microscopy studies and in vitro antifungal susceptibility tests were conducted. Through the combination of these investigations, the isolate was identified as P. wickerhamii and the patient was successfully treated with intravenous amphotericin B and itraconazole. This is the first detailed report of meningitis caused by P. wickerhamii in China.

Onychoprotothecosis: report of the first case in Brazil

The present report describes a case of onychoprotothecosis caused by Prototheca wickerhamii in a nonimmunocompromized female. Dermatological examination showed yellowish discoloration of the left and right forefinger nails, showing onicolysis and hyperkeratosis. The repeated isolation of the algae Prototheca (organisms morula-like) as well as the repeated culture in media, Sabouraud agar, confirmed the diagnosis. The patient was successfully treated with tioconazol 1% topic solution. The aim of this paper was to present a rare condition.

Cutaneous protothecosis: report of a third Brazilian case

The present report describes a case of cutaneous protothecosis caused by Prototheca wickerhamii in a nonimmunocompromised Brazilian female. Dermatological examination revealed a 15-cm diffusely infiltrated eczema-like plaque recovered with many pustule-like lesions on the right forearm. We emphasize the mycological and pathological aspects of this infection that can lead to misdiagnosis. The patient was successfully treated with itraconazole.

A case report of canine protothecosis

A 10-year-old spayed mongrel dog was referred with repeated intercurrent hematochezia and anal bleeding. The dog was vigorous and had a normal appetite, and the fecal test showed no abnormal signs. Despite treatment primarily with sulfasalazine, the condition did not improve and unilateral blindness developed. A Prototheca zopfii infection was identified by further examination with bowel culture on Sabouraud's agar without cyclohexane and antibiotics. Subsequent to a vision loss in the other eye, the dog died showing signs of neurological disorder.

Protothecosis in patients with cancer: case series and literature review

OBJECTIVE

To review our recent experience with protothecosis in patients with cancer at The University of Texas MD Anderson Cancer Center, and compare these cases with others reported in the literature.

METHODS

We report on three patients with protothecosis and cancer who were seen at The University of Texas MD Anderson Cancer Center from January 1979 to May 2002, and reviewed all cases of protothecosis in patients with cancer reported in the literature since 1966.

RESULTS

Overall, 13 cases of protothecosis complicating cancer were evaluated. The median age of the patients was 41 years (range, 7-73 years). Seven patients (54%) had an underlying hematologic malignancy, and one infection occurred after bone marrow transplantation. Neutropenia was uncommon in these patients (14%). Prototheca wickerhamii was the most common Prototheca species identified as the causative agent of infection. Skin infection was the most common presentation of protothecosis, occurring in five patients (38%), followed by disseminated disease in three patients (23%), algaemia in three patients (23%), pulmonary infection in one patient (8%), and olecranon bursitis in one patient (8%). Information on the use of antifungal therapy was available for ten patients. Seven of the ten patients received amphotericin B, while three received triazoles (fluconazole in two, itraconazole in one). Breakthrough protothecosis occurred during the administration of systemic antifungal therapy with itraconazole in one patient. All seven patients who received amphotericin B showed a response, as did one of the three patients given triazoles. Seven (58%) of the patients died during the study period, only one (17%) of protothecosis.

CONCLUSIONS

Protothecosis is an uncommon infection in cancer patients, implying that Prototheca spp. have a low pathogenic potential in this population. Pulmonary involvement in particular is uncommon in these patients. Amphotericin B appears to be the most effective antifungal agent; the role of triazoles in treating protothecosis is uncertain, but they may be less effective.

Protothecosis

Intravenous amphotericin B remains the most effective drug for eradicating Prototheca infections. It should be used as a first-line agent in cases of disseminated disease and in patients with severe underlying illness or with immunosuppression or immunocompromise. Azole antifungals and surgery should be reserved for patients with more localized disease. Itraconazole appears to be the most effective agent of this drug class, and it should be administered at 200 mg/day for 2 months. Surgical excision should be considered as a first-line therapy in patients who present with olecranon bursal infections.

Cutaneous protothecosis: report of the second Brazilian case

The present report describes a case of cutaneous protothecosis caused by Prototheca wickerhamii in a non-immunocompromised female from the state of Bahia, Brazil. This is the second case described in Brazil. Dermatological examination revealed diffusely infiltrated erythematous plaques on the flexor aspect of the right arm and forearm. The authors emphasize the pathological aspects that can lead to misdiagnosis this condition. The patient was successfully treated with fluconazole.

Two cases of protothecosis in Nagoya, Japan

Two cases of protothecosis caused by Prototheca wickerhamii have been reported from Nagoya in a 12 year period in both cases the infection presented on the cheeks of otherwise healthy women. Biopsies showed numerous PAS positive staining organisms with the distinctive mulberry like endosporulation in the dermis. Prototheca wickerhamii was identified on sugar assimilation tests of colonies isolated from tissue on Sabouraud agar. Case 1 responded to 11 months of oral ketoconazole therapy. Case 2 might not respond to itraconazole. The source of the infections has not been identified.

Simple new test for rapid differentiation of Prototheca stagnora from P. wickerhamii and P. zopfii

A simple new test to differentiate Prototheca wickerhamii and P. zopfii from P. stagnora by determining susceptibility to neomycin is described. Susceptibility determined using a 30 micrograms neomycin disk provides a rapid and reliable means of distinguishing P. wickerhamii and P. zopfii from P. stagnora.

Mycotic and algal bovine mastitis in Denmark

A one-year examination of mammary secretions (n = 2,896) from Danish cattle with clinical or subclinical mastitis revealed 45 strains of fungi and algae. The strains originated from 44 mammary secretions of 42 cows in 40 herds. The following species of fungi were identified: Candida catenulata (n = 2), Candida kefyr (n = 6), Candida krusei (n = 17), Candida rugosa (n = 6), Candida tropicalis (n = 3), Candida valida (n = 1), Geotrichum capitatum (n = 5). The algal species Prototheca zopfii was demonstrated in five samples.

Protothecosis: a report of two cases in Japan and a review of the literature

Protothecosis is an emerging opportunistic infection caused by species belonging to the genus Prototheca. Two Japanese cases of protothecosis are documented with a critical review of the literature. A current perspective concerning the microbiology and disease entity of protothecosis is described in detail.

Successful treatment of Prototheca peritonitis complicating continuous ambulatory peritoneal dialysis

We describe the second reported case of peritonitis caused by the alga Prototheca wickerhamii in a patient on continuous ambulatory peritoneal dialysis (CAPD). This organism, which grows slowly on agar media, is recognised as a race cause of other infections. The condition is clinically similar to cases of fungal peritonitis, but there are important differences, particularly when choosing the best treatment.

First case of human protothecosis in Canada: laboratory aspects

A case of bursitis due to Prototheca wickerhamii is briefly reported. In histological sections the organism stained well with fungal stains, grey with silver methanamine and red with periodic acid Schiff reagent. This unicellular achlorophyllous alga was studied on common laboratory media. The characterization of the Prototheca sp. depends largely on wet mount microscopic examination from broth or agar cultures which ensures the observation of endosporulation and a consistent absence of budding. Otherwise the growth rate and the pasty white colonies may lead to an erroneous identification, most likely as a Cryptococcus sp. P. wickerhamii lends itself very well to standard physiological tests used for the identification of yeasts. The strain was found insensitive to 5-fluorocytosine. The MIC of amphotericin B was 0.15 microgram/ml.