Human Cutaneous Protothecosis: A Case Report and Review of Cases from Mainland China, Hong Kong, and Taiwan

Combinatory effect of ALA-PDT and itraconazole in the treatment of cutaneous protothecosis

BACKGROUND

As a rare subcutaneous infection, protothecosis is easily misdiagnosed. Similar to other subcutaneous infection, there is no unified standard for treatment, for cases not suitable for surgery, clinicians often use antifungal drugs based on their experience, and the course of treatment varies from several months to several years. Based on the fact that there are few relevant materials and researches on photodynamic therapy (PDT), we conducted a study based on a clinical case that used oral itraconazole combined with 5-aminolevylinic acid photodynamic therapy (ALA-PDT) to treat a patient with cutaneous protothecosis caused by Prototheca wicherhamii.

METHODS

Different concentrations of ALA and different light doses were used to investigate the effects of ALA-PDT on the growth inhibition of P. wickerhamii in vitro with Colony-counting Methods. And we used transmission electron microscopy (TEM) to visualize the structural changes and the effects of ALA-PDT treating on cellular structures of the P. wickerhamii. Futher, we performed the susceptibility test of P. wickerhamii to itraconazole before and after ALA-PDT in vitro.

RESULTS

We have successfully treated a patient with cutaneous protothecosis caused by P. wickerhamii by using combination therapy in a total of 9-week course of treatment. In vitro, ALA-PDT can inhibit the growth of P. wickerhamii when the ALA concentration was 5 mg/mL (P < 0.01), and this effect became stronger as the concentration of ALA or light dose is increased. Using TEM, we confirmed that ALA-PDT can disrupt the cell wall structure and partition structure of P. wickerhamii, which may contribute to its inhibitory effect. Further studies showed that the MIC of itraconazole for P. wickerhamii was decreased after ALA-PDT.

CONCLUSIONS

ALA-PDT combined with oral itraconazole can be used to treat cutaneous protothecosis. Accordingly, ALA-PDT can destroy the cell wall and partition structure of P. wickerhamii leading to an inhibitory effect on it in vitro, and the effect is enhanced with the increase of ALA concentration and light dose. Also, the sensitivity of P. wickerhamii to itraconazole is observed increased after ALA-PDT. So our study provides a theoretical basis for the promising treatment against cutaneus protothecosis.

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.

Simultaneous infection with Fusarium proliferatum and Prototheca wickerhamii localized at different body sites

2012 Elsevier Ltd. All rights reserved. Subcutaneous infections caused by two unusual fungi are rare. Here we report an elderly woman with long-term glucocorticoid use who was infected with Fusarium proliferatum on the right dorsum of the hand presenting with a verrucous plaque and Prototheca wickerhamii on the left dorsum of the hand presenting with geographic ulcers with erythematous plaques. The diagnosis was made through histopathological examination of skin samples and fungal culture, with identification through molecular examination. She was successfully treated with voriconazole.

Burden of ischemic stroke in mainland China and Taiwan province from 1990 to 2019: with forecast for the next 11 years

Ischemic stroke is featured with high incidence, mortality, and disability. The aim of this study is to use Global Burden of Disease database to describe and compare the burden of ischemic stroke in mainland China and Taiwan province and to further predict the expected changes in the next 11 years using statistical modeling methods. Information on ischemic stroke incidence and mortality in China (mainland and Taiwan province) during 1990-2019 was obtained from the Global Burden of Disease database to analyze the effects of region, gender, and age on the incidence and mortality of ischemic stroke in China. The autoregressive integrated moving average model was used to predict the age-standardized incidence rate and age-standardized mortality rate of ischemic stroke in males and females in mainland China and Taiwan province in the next 11 years. The period from 1990 to 2019 witnessed an overall upward trend in the number of incidence and deaths in mainland China and Taiwan province. In 2019, there were nearly 2.87 million ischemic incidence cases with stroke in mainland China, with more female patients than male in the age group of over 60 years. Among the nearly 1.03 million deaths, the death toll of men under the age of 85 years was higher than that of women, while in Taiwan province, the number of incidence was 28 771, with more female patients of all ages than male. Among the 6788 deaths, the death toll of men under the age of 80 years was higher than that of women. In 2019, the age group with the highest number of patients in the two regions was 65-69 years, while the highest number of deaths was found in people aged 85 years and above. As our autoregressive integrated moving average model predicted, the age-standardized incidence rate value of ischemic stroke is expected to be 163.23/100 000 persons in mainland China by 2030, which would continue to increase, while the age-standardized mortality rate value of ischemic stroke is expected to be 16.41/100 000 persons in Taiwan province by 2030, which showed a decreasing trend. Disease burden of ischemic stroke is still increasing in mainland China and Taiwan province, and health resources should be deployed to implement effective prevention and control strategies, taking into account region, gender, and age.

Human protothecosis: A case report in northeastern Brazil

We describe a case of extensive human cutaneous protothecosis in the northeastern of Brazil. The diagnosis was made through histopathological examination of skin samples and culturing on Sabouraud dextrose agar, with identification through mass spectrometry. Treatment with itraconazole failed and was switched to liposomal amphotericin followed by voriconazole with clinical cure. Prothotecosis should be a diagnostic hypothesis when there are skin lesions after trauma, specially in situations of atypical evolution.

Cutaneous Protothecosis with Meningitis Due to Prototheca wickerhamii in an Immunocompetent Teenager: Case Report and Literature Review

Human protothecosis is a rare infection caused by Prototheca spp., which are environmental achloric algae ubiquitously existing in nature. Members of the genus of Prototheca usually cause localized infection that affects the skin or wounds. Systemic infection is extremely rare and tends to occur in immunocompromised patients. Here, we report a case of cutaneous protothecosis and meningitis due to Prototheca wickerhamii in an immunocompetent teenager who obtained full-body tattoos at the time of infection. To the best of our knowledge, this is the first description of P. wickerhamii isolated from both skin tissue and cerebrospinal fluid. The data contained in this report will increase our understanding of this pathogen and elucidate the most optimal treatment.

Characterization of Prototheca CYP51/ERG11 as a possible target for therapeutic drugs

Prototheca spp. are achlorophyllous algae, ubiquitous in nature. An increasing number of human and animal cases of Prototheca infection (protothecosis) are reported, and antifungal azoles, which inhibit sterol 14α-demethylase (CYP51/ERG11) involved in ergosterol biosynthesis, have empirically been used for the treatment of protothecosis. Although Prototheca, like fungi, has ergosterol in the cell membrane, efficacy of the antifungal azoles in the treatment of protothecosis is controversial. For investigating the interaction of azole drugs with Prototheca CYP51/ERG11, the CYP51/ERG11 genomic genes of four strains of P. wickerhamii and one strain each of P. cutis and P. miyajii were isolated and characterized in this study. Compared with the CYP51/ERG11 gene of chlorophyllous Auxenochlorella Protothecoides, it is possible that ProtothecaCYP51/ERG11 gene, whose exon-intron structure appeared to be species-specific, lost introns associated with the loss of photosynthetic activity. Analysis of the deduced amino acid sequences revealed that Prototheca CYP51/ERG11 and fungal CYP51/ERG11 are phylogenetically distant from each other although their overall structures are similar. Our basic in silico studies predicted that antifungal azoles could bind to the catalytic pocket of Prototheca CYP51/ERG11. It was also suggested that amino acid residues away from the catalytic pocket might affect the drug susceptibility. The results of this study may provide useful insights into the phylogenetic taxonomy of Prototheca spp. in relationship to the CYP51/ERG11 structure and development of novel therapeutic drugs for the treatment of protothecosis.

LAY SUMMARY

Cases of infection by microalgae of Prototheca species are increasing. However, effective treatment has not been established yet. In this study, gene and structure of Prototheca's CYP51/ERG11, an enzyme which might serve as a target for therapeutic drugs, were characterized for the first time.

Multiple cutaneous infections caused by Prototheca wickerhamii

Background

Prototheca species are a group of organisms ubiquitously existing in nature but have become a pathogenic threat to public health, which has aroused wide attention. Species identification and antifungal susceptibility have essential and valuable meanings to clinical diagnosis and treatment.

Methods

A case of an 84‐year‐old patient who had suffered from multiple cutaneous infections was reported. Tissue samples of the damaged skin were collected from the patient and used for microscopic examination and tissue culture. Staining methods, the VITEK system with YSD card and the molecular identification method based on partial mitochondrion‐encoded cytochrome b (cytb) gene amplification and sequencing were used for species identification. Antifungal susceptibility testing was completed by using YeastOne plate.

Results

The patient had type II diabetes mellitus. Round, grape‐like, and scattered morula forms were observed under the microscope in bright blue with lactophenol cotton blue staining and in green fluorescence with fungus fluorescence staining. Yeast‐like colonies were grown on both the blood plates and the Sabouraud agar. P wichehamii was identified and presented resistance to three echinocandins, fluconazole, and 5‐fluorocytosine, while was susceptible to amphotericin B, posaconazole, itraconazole, and voriconazole.

Conclusion

Our result revealed that an old patient with diabetes mellitus might be a dangerous population of cutaneous protothecosis. It also highlighted the contribution to microbial methodology on the diagnosis and treatment of such rare fungus infection.

The foot microbiome

BACKGROUND

The human skin microbiome is represented by bacteria, fungi, viruses, and mites.

AIMS

Every human being possess their own unique skin microbiome because intrinsic and environmental factors have a significant impact on the quality and quantity of microorganism. Every site of the body is a separate microbial niche.

PATIENTS

The feet are one of the most unique and heterogeneous microbial niches of human body with areas that differ by skin thickness, anatomical features, distribution of sweat glands, pH, and the availability of oxygen.

RESULTS

Healthy skin of the foot is inhabited by Corynebacteriaceae, Micrococcaceae, Propionibacteriaceae, Actinobacteria, Clostridiales, Lactobacillaceae, Streptococcaceae, Enterobacteriaceae, Moravellaceae, Neisseriaceae, Pastereullaceae, and Proteobacteria. The most common fungi present on the feet are Malassezzia, Cryptococcus, Aspergillus, Rhodotorula, Epicoccum, Saccharomyces, Candida, Epidermophyton Microsporum, and Trichophyton.

CONCLUSIONS

The disturbance of the foot microbiome causes dysbiosis and may lead to pitted keratolysis, fungal, and viral infections or even to protothecosis.

Prototheca wickerhamii prepatellar bursitis in an immunocompetent woman: A case report

Prototheca wickerhamii is a rare cause of septic prepatellar bursitis. We report a patient who had no apparent immunodeficiency developed P. wickerhamii prepatellar bursitis following intra-bursal corticosteroid injection. Clinical manifestations could not distinguish Prototheca bursitis from septic bursitis caused by other pathogens. Bursal fluid aspiration sent for direct microscopic examination and cultures could give an early diagnosis. Systemic antifungal therapy with complete surgical excision of infected bursa provided a good outcome.