Cutaneous protothecosis: report of five cases

Successful treatment of cutaneous protothecosis with fluconazole: A case report and epidemiology study of Prototheca infection in China

BACKGROUND

Protothecosis is an infection of humans and animals caused by a rare conditionally pathogenic fungus (prototheca). It can occur in immunocompromised or normal patients.

AIMS

To describe the epidemiology of prototheca infection in China.

METHODS

We report a case of successful treatment of cutaneous protothecosis with fluconazole and analyzed the epidemiological characteristics, risk factors, clinical manifestations, diagnosis, treatment and prognosis of prototheca infections in China.

RESULTS

We describe this case and 29 cases of prototheca infections in China. At present, Prototheca wickerhamii (Pw) infection is the most common infection in China, and single or combined itraconazole is the preferred treatment.

CONCLUSIONS

These results provide detailed information and relevant clinical treatment strategies for the diagnosis and treatment of protothecosis in China.

Successful Treatment of Cutaneous Protothecosis Due to Prototheca wickerhamii with Terbinafine

Protothecosis, an infrequent human infection, is caused by achlorophyllic algae belonging to the genus Prototheca, particularly Prototheca wickerhamii. The skin stands as the most commonly affected organ. This report documents a case involving an 82-year-old male with Protothecosis. Histopathological analysis revealed granulomatous inflammation in the dermis, exhibiting necrotic features and hosting numerous non-budding spherical organisms. These organisms were positively stained using methenamine silver and periodic acid-Schiff stains, confirming identification as P. wickerhamii after validation through tissue culture and sequencing procedures. Initially, the patient received oral itraconazole at a dosage of 200 mg daily, accompanied by topical 1% naftifine-0.25% ketoconazole cream for a duration of 4 weeks, resulting in significant improvement. Subsequently, due to gastrointestinal discomfort presumably linked to itraconazole, terbinafine was administered. Over a span of 3 months, the patient received oral terbinafine at a dosage of 250 mg/day alongside the application of topical 1% naftifine-0.25% ketoconazole cream, leading to complete healing of the skin lesion, leaving behind a fibrotic scar.

New Approaches for risk assessment and management of bovine protothecosis

Protothecosis is a potential zoonosis related to bovine mastitis. In several countries, a higher incidence of protothecal bovine mastitis that is being recorded and the resistance of Prototheca species to various factors (chlorine, high temperatures, antimicrobial and antiseptic treatments, pH variations), make it difficult to control its spread among farms. The authors aim to describe the infection caused by microalgae, focusing on the problems within cattle farms and proposing new approaches to farm management, based on Regulation (EU) No 2016/429 on transmissible animal diseases. This new flexible approach, based on risk analysis, is a further tool in protecting against Prototheca species. The list of transmissible animal diseases under Regulation (EU) No 2016/429 includes those caused by microorganisms resistant to antimicrobials, which can have important implications for human and animal health, feed and food safety. This approach would involve a series of changes to the rules used for Official Controls (Regulation (EU) No 2017/625) moving from the concept of the food chain to that of the agri-food chain.

Protothecosis algaemia in a patient presenting with septic arthritis: A rare case of Prototheca zopfii isolated from Malaysia

Prototheca species have been reported to cause infections in human. Typically, clinical symptoms of protothecosis include cutaneous infection, olecranon bursitis, tenosynovitis and disseminated systemic disease. We report a case of septic arthritis in which Prototheca zopfii was isolated from blood. Joint aspirate was also sent for cultures but did not yield any growth. No other organisms were isolated from this patient during his admission. The blood isolate was identified to species level via Polymerase Chain Reaction (PCR) method. The patient improved with administration of intravenous itraconazole.

Murine and Human Cathelicidins Contribute Differently to Hallmarks of Mastitis Induced by Pathogenic Prototheca bovis Algae

Prototheca bovis (formerly P. zopfii genotype-II) is an opportunistic, achlorophyllous alga that causes mastitis in cows and skin disease in cats and dogs, as well as cutaneous lesions in both immunocompetent and immunosuppressed humans. Antifungal medications are commonly ineffective. This study aimed to investigate innate immune responses contributed by cathelicidins to P. bovis in the mammary gland using a mastitis model in mice deficient in the sole murine cathelicidin (Camp). We determined P. bovis caused acute mastitis in mice and induced Camp gene transcription. Whereas, Camp-/- and Camp+/+ littermates had similar local algae burden, Camp+/+ mice produced more pro-inflammatory cytokines, TNF-α, and Cxcl-1. Likewise, Camp+/+ bone marrow-derived macrophages were more responsive to P. bovis, producing more TNF-α and Cxcl-1. Human cathelicidin (LL-37) exhibited a different effect against P. bovis; it had direct algicidal activity against P. bovis and lowered TNF-α, Cxcl-1, and IL-1β production in both cultured murine macrophages and mammary epithelial cells exposed to the pathogenic algae. In conclusion, cathelicidins were involved in protothecosis pathogenesis, with unique roles among the diverse peptide family. Whereas, endogenous cathelicidin (Camp) was key in mammary gland innate defense against P. bovis, human LL-37 had algicidal and immunomodulatory functions.

Clinicopathological features and course of cutaneous protothecosis

BACKGROUND

Protothecosis is an uncommon infection caused by the achlorophyllic algae found more commonly in tropical areas. Only a limited number of cases have been reported.

OBJECTIVE

We aimed to evaluate the clinicopathological features and treatment outcomes of cutaneous protothecosis.

METHODS

We retrospectively identified 20 pathology-confirmed cases of cutaneous protothecosis based on skin biopsies in two tertiary medical centres in Taiwan from 1997 to 2015.

RESULTS

The age of the patients at the time of diagnosis ranged from 48 to 85 years (mean age of 74 years). All lesions developed on the limbs. Twelve (60%) patients had adrenal insufficiency, but no patients had active malignancy at diagnosis. Interestingly, four (20%) patients had concurrent scabies infestation. Clinically, most lesions were erythematous plaques studded with punctate ulcers. Microscopically, the most common finding was granulomatous inflammation. Nineteen (95%) cases were successfully treated with itraconazole for 14-148 days with only one case of recurrence. Concomitant scabies should be suspected if pruritus is recalcitrant despite itraconazole treatment.

CONCLUSION

Despite its rarity, cutaneous protothecosis has become more significant due to an increased prevalence of immunocompromised individuals. Steroid overuse or iatrogenic adrenal insufficiency predisposes individuals to high-risk infections. Neglecting the disease leads to a chronic and incurable state. Protothecosis should be suspected in chronic eczematous and ulcerative plaques on the limbs refractory to conventional antibacterial and antiviral treatments, especially in patients with adrenal insufficiency. Clinical suspicion should be confirmed by skin biopsies, and confirmed cases can be successfully treated with itraconazole.

Protothecal bursitis after simultaneous kidney/liver transplantation: a case report and review

Solid organ transplantation is an accepted therapy for end-stage diseases of the kidneys, liver, heart, and lungs. Unfortunately, transplantation is associated with infectious complications. Here, we present a case report of Prototheca wickerhamii olecranon bursitis and review all of the cases in solid organ transplant (SOT) recipients published in the literature to date. In our patient, the infection resolved with surgical therapy and limited antifungal therapy, and no symptoms have recurred over 24 months of follow-up. A review of the literature suggests that 50% of SOT recipients with Prototheca infection present with disseminated infection, and the overall mortality is 75%. More studies are required to determine the optimal management of protothecosis in this population.

Well-known surface and extracellular antigens of pathogenic microorganisms among the immunodominant proteins of the infectious microalgae Prototheca zopfii

Microalgae of the genus Prototheca (P.) are associated with rare but severe infections (protothecosis) and represent a potential zoonotic risk. Genotype (GT) 2 of P. zopfii has been established as pathogenic agent for humans, dogs, and cattle, whereas GT1 is considered to be non-pathogenic. Since pathogenesis is poorly understood, the aim of this study was to determine immunogenic proteins and potential virulence factors of P. zopfii GT2. Therefore, 2D western blot analyses with sera and isolates of two dogs naturally infected with P. zopfii GT2 have been performed. Cross-reactivity was determined by including the type strains of P. zopfii GT2, P. zopfii GT1, and P. blaschkeae, a close relative of P. zopfii, which is known to cause subclinical forms of bovine mastitis. The sera showed a high strain-, genotype-, and species-cross-reactivity. A total of 198 immunogenic proteins have been analyzed via MALDI-TOF MS. The majority of the 86 identified proteins are intracellularly located (e.g., malate dehydrogenase, oxidoreductase, 3-dehydroquinate synthase) but some antigens and potential virulence factors, known from other pathogens, have been found (e.g., phosphomannomutase, triosephosphate isomerase). One genotype-specific antigen could be identified as heat shock protein 70 (Hsp70), a well-known antigen of eukaryotic pathogens with immunological importance when located extracellularly. Both sera were reactive to glyceraldehyde-3-phosphate-dehydrogenase of all investigated strains. This house-keeping enzyme is found to be located on the surface of several pathogens as virulence factor. Flow-cytometric analysis revealed its presence on the surface of P. blaschkeae.

Cutaneous Protothecosis in a Patient with Chronic Lymphocytic Leukemia: A Case Report and Literature Review

Protothecosis is a rare infection, which has the potential to cause severe disease in patients with underlying immunosuppression. We describe a case of an elderly female with chronic lymphocytic leukemia (CLL), as well as other risk factors, who presented with pustular and erythematous plaques, initially presumed to be leukemia cutis. A biopsy with special stains revealed the lesions to be cutaneous protothecosis, thus presenting a most unusual concurrence of disease entities. The literature to date on this rare infection will be reviewed.

Cutaneous protothecosis--case report

Cutaneous protothecosis is a rare infection caused by achlorophyllic algae of the genus Prototheca. The lesions usually occur on exposed areas, related with trauma, in immunocompromised patients. The most common clinical presentation is a vesicobullous and ulcerative lesion with pustules and scabs, simulating bacterial, fungal or herpetic infections or eczema. The diagnosis is determined by agent identification through histopathology, culture and the carbohydrates assimilation test. The finding of morula-like spherules is characteristic of Prototheca sp. Its rarity and non-specific clinical aspect may difficult the disease diagnosis. We report a case of a diabetic patient, in chronic use of systemic corticosteroids, that developed a skin lesion after trauma to the right leg.

Antimicrobial activity of Mentha piperita and Saturenja hortensis in a murine model of cutaneous protothecosis

BACKGROUND

To date there is no defined pharmacologic treatment protocol available against cutaneous protothecosis, which is difficult to combat using conventional drugs.

OBJECTIVES

Our experiment aimed to comparatively investigate the effect of two essential oils (Mentha piperita and Saturenja hortensis) against cutaneous protothecosis experimentally induced by Prototheca zopfii in mice.

MATERIALS AND METHODS

Immunosuppressed BALB/c female mice, were divided into six experimental groups, infected with P. zopfii, and then treated for 21 days against the infection. The effectiveness of the different treatments was assessed clinically and histologically by quantifying the degree of inflammation (immunohistochemical quantification of macrophages, T lymphocytes and neutrophils) and fibrosis.

RESULTS

Skin lesions in experimental protothecosis from non-treated mice were more severe as compared to the four groups of treated animals. Both M. piperita and S. hortensis have proved to be efficient in vivo in the treatment of cutaneous protothecosis by reducing the clinical signs and significantly reducing the degree of inflammation (P<0.05 for the number of macrophages, T lymphocytes and neutrophils) and fibrosis as compared to untreated animals.

CONCLUSION

Interestingly, our study shows that M. piperita and S. hortensis could represent a potential source of natural antimicrobial products in the treatment of cutaneous protothecosis.

Human cutaneous protothecosis: report of a case and literature review

The Prototheca species is achlorophyllic algae and rarely causes human infection. Human protothecosis presents clinically as a cutaneous infection, olecranon bursitis, and disseminated systemic disease. We report a case of human cutaneous protothecosis involving the left wrist. A 68-year-old man presented with an ill-defined erythematous lesion with crust at the dorsal aspect of his left wrist. A punch biopsy was performed to reveal the histologic features of granulomatous inflammation with necrosis at the upper dermis, containing Prototheca organisms, of which, the characteristic features were highlighted by special staining. Through a molecular study, the Prototheca zopfii species was identified.

Prototheca wickerhamii infection of a corneal graft

Algae are generally noninfectious agents in mammals, with few known pathogenic algae. Prototheca is an achlorophylic nonphotosynthetic algae, globally ubiquitous, and readily isolated from rivers, lakes, ponds, and soil. Although canine and bovine protothecosis have been reported more widely, infections in humans are rare, particularly in patients with an intact immune system. The majority of protothecal infections in humans is associated with Prototheca wickerhamii. We report an unusual case of P. wickerhamii infection in an immunocompetent corneal transplant patient.

Cutaneous Protothecosis

Prototheca species are an achlorophyllic algae that cause infections primarily in immunocompromised individuals. At least one-half of infectious cases are cutaneous. Because protothecosis is seldom suspected clinically, patients may be subjected to various treatment modalities for extended periods without satisfactory results. Cutaneous protothecosis shares similar clinical and pathologic findings with deep tissue fungal mycoses. The typical presentation occurs most commonly on the face and extremities as erythematous plaques, nodules, or superficial ulcers. Prototheca spp are spherical, unicellular, nonbudding organisms that are sometimes noted on routine hematoxylin-eosin staining but are best visualized with periodic acid–Schiff and Gomori methenamine-silver histochemical stains. Although protothecosis can be diagnosed on biopsy, culture of the organism on a medium such as Sabouraud dextrose agar is required for definitive diagnosis. Treatment may require a combination of surgical excision and antifungal agents. Therefore, cutaneous protothecosis should be considered in a lesion that appears suspicious for the more-common fungal infections.

Aquatic sports dematoses. Part 2 - in the water: saltwater dermatoses

The second part of this three-part series on water-related dermatoses will discuss dermatologic conditions seen in athletes exposed to saltwater. The vast majority of the following dermatoses result from contact with organisms that inhabit saltwater, including bacteria, cnidarians, and echinoderms. This review also will include other dermatoses affecting saltwater athletes and should serve as a guide for dermatologists, sports medicine physicians, and other medical practitioners in recognition and treatment of these dermatoses.

Disseminated protothecosis

Here is presented, a rare case of disseminated protothecosis in a 10-year-old boy with combined immunodeficiency, hitherto unreported from India. Even though it is difficult to diagnose clinically, observation of the sporangiospores within the sporangium in culture gives the accurate laboratory identification of Prototheca spp. In this patient, failure to eradicate the infection with amphotericin B and recurrence with olecranon bursitis along with skin lesions and splenomegaly was observed. Disseminated protothecosis in a child with combined immunodeficiency and failure to eradicate the infection with amphotericin B is reported.

An unusual case of granulomatous lymphadenitis due to Prototheca zopfii var. portoricensis in an immunocompetent man in China

BACKGROUND

Protothecosis is an uncommon human infection caused by Prototheca. Prototheca spp can be considered as saprophytes, and in spite of their frequency in the environment, they are of low virulence and may cause chronic infection with low-grade inflammation in humans. At present, only three species are recognized: Prototheca wickerhamii, Prototheca zopfii and Prototheca stagnora. Of these, the former two have been associated with human disease. This study was an investigation of the clinical and microbiological features of a case of granulomatous lymphadenitis due to P. zopfii var. portoricensis in an immunocompetent man in China.

METHODS

We report the case of a 39-year-old male, who presented with swollen lymph nodes, from which the organism was isolated and identified by the RapidID Yeast Plus test (Remel, Santa Fe, NM, USA) and PCR molecular analysis. The pathogenicity of the isolate was confirmed in a mouse model and antifungal drug susceptibility testing was carried out.

RESULTS

The pathogen was identified as Prototheca zopfii. The DNA sequence of the 18S SSU rDNA regions of the isolate strain were 100% (1205/1205) identical with Prototheca zopfii var. portoricensis. Antifungal susceptibility tests revealed that it was sensitive to amphotericin B, but resistant to 5-flucytosine, fluconazole, ketoconazole, and itraconazole. The patient responded to treatment with intravenous itraconazole and amphotericin B.

CONCLUSIONS

Based on the patient's symptoms and microscopic evaluation, cultures, and molecular analyses of the isolate, granulomatous lymphadenitis due to P. zopfii var. portoricensis was diagnosed. P. zopfii var. portoricensis as a causative agent of human lymphadenitis in an immunocompetent case has not been reported, though a few cases of protothecosis have been reported in China. The real number of protothecosis cases may be greater than that reported in the literature. Thus, clinicians should be vigilant for any unknown cause of granulomatous lymphadenitis and should undertake an intensive histopathology, mycology examination, and even molecular analysis to rule out or confirm a potential Prototheca infection.

Cutaneous Protothecosis following a Tape-Stripping Injury

Background:

Prototheca species are ubiquitous achlorophyllic algae that can, in rare instances, manifest as cutaneous infection in humans at sites of traumatic inoculation into the skin.

Objectives:

We report a 77-year-old man who developed cutaneous protothecosis at the site of an iatrogenic tape-stripping type injury. The diagnosis was confirmed by histologic examination and tissue culture. The patient responded completely to a 17-week course of oral fluconazole.

Conclusion:

Cutaneous protothecosis can present clinically as nonspecific indolent inflammatory plaques that require skin biopsy for definitive diagnosis.

Prototecose cutânea: relato de caso

Descreve-se um caso de prototecose cutânea em paciente de 78 anos, submetido a tratamento para pênfigo foliáceo e feohifomicose. Ele apresentava lesões eritematosas infiltradas na perna direita e o diagnóstico foi feito através de estudo histológico e através de cultura da pele lesada. A cura foi obtida com o uso oral de itraconazol.

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.

Protothecosis in 17 Australian dogs and a review of the canine literature

Systemic protothecosis was diagnosed in 17 Australian dogs between 1988 and 2005. There was a preponderance of young-adult (median 4 years), medium- to large-breed dogs. Females (12/17 cases) and Boxer dogs (7 cases, including 6 purebreds and one Boxer cross) were over-represented. Sixteen of 17 dogs died, with a median survival of four months. A disproportionate number of cases were from coastal Queensland. In most patients, first signs were referable to colitis (11/17 cases), which varied in severity, and was often present for many months before other symptoms developed. Subsequent to dissemination, signs were mostly ocular (12 cases) and/or neurologic (8 cases). Two dogs had signs due to bony lesions. Once dissemination was evident, death or euthanasia transpired quickly. Prototheca organisms had a tropism for the eye, central nervous system (CNS), bone, kidneys and myocardium, tissues with a good blood supply. Microscopic examination and culture of urine (5 cases), cerebrospinal fluid (CSF;1 case), rectal scrapings (4 cases), aspirates or biopsies of eyes (5 cases) and histology of colonic biopsies (6 cases) as well as skin and lymph nodes (2 cases) helped secure a diagnosis. Of the cases where culture was successful, P wickerhamii was isolated from two patients, while P zopfii was isolated from five. P zopfii infections had a more aggressive course. Treatment was not attempted in most cases. Combination therapy with amphotericin B and itraconazole proved effective in two cases, although in one of these treatment should have been for a longer duration. One surviving dog is currently still receiving itraconazole. Protothecosis should be considered in all dogs with refractory colitis, especially in female Boxers.

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.

In vitro activity of voriconazole against Prototheca wickerhamii: comparative evaluation of sensititre and NCCLS M27-A2 methods of detection

A total of 104 Prototheca wickerhamii isolates and two control strains were tested for susceptibility to voriconazole using the Sensititre YeastOne colorimetric antifungal plate and NCCLS reference method. Voriconazole was highly active against all isolates, with an MIC at which 90% of isolates were inhibited of < or = 0.5 microg/ml. Comparison of MICs obtained with the Sensititre product and the NCCLS method demonstrated agreement (100% +/- 2 log2 dilutions) between the two methods. Voriconazole may offer an option for the treatment of Prototheca sp. infections, and its efficacy should be established through clinical experience.

Protothecosis successfully treated with amikacin combined with tetracyclines. Fallbericht. Protothecose erfolgreich mit Amikacin plus Tetracyclinen behandelt

Summary We report a case of protothecosis in an 18-year-old female student caused by Prototheca zopfii successfully treated with amikacin combined with tetracyclines. Zusammenfassung Es wird über eine Protothecose, verursacht durch Prototheca zopfii, bei einer 18-jährigen Studentin berichtet, die erfolgreich mit Amikacin in Kombination mit Tetracyclinen behandelt wurde.

Longitudinal analysis of Prototheca zopfii-specific immune responses: correlation with disease progression and carriage in dairy cows

In order to characterize the humoral and cellular immune responses to bovine mammary protothecosis, serum and whey samples obtained from 72 dairy cows assigned to four different clinical stages of infection were examined for specific antibodies by indirect enzyme-linked immunosorbent assay techniques. Milk samples were analyzed for the total numbers of excreted algal cells and somatic cells. After characterization of the course of immune induction in bovine protothecal mastitis, a long-term sentinel study was performed in an affected herd in order to investigate disease progression. A total of 61 dairy cows with protothecal mastitis were examined for shedding of algae cells and for local immune responses three times in 6-month intervals. During acute and chronic stages of protothecosis, significantly elevated specific antibody activities in sera were detected. A strong correlation of whey immunoglobulin A (IgA) and whey IgG1 antibody activity with the total counts of somatic cells in milk was observed, whereas only a weak correlation of whey IgA and whey IgG1 concentrations to the number of algal cells excreted with the milk was seen. Our results from the sentinel long-term study of infected cows revealed that 70.5% of the persistently infected animals were continuously shedding the pathogen. About 4.9% of the animals showed an intermittent shedding, whereas 18% of the cows were tested culturally negative throughout the study. It can be assumed that Prototheca zopfii mastitis in dairy cows is maintained on the herd level by subclinically infected alga-shedding cows.