Cutaneous Protothecosis in Patient with Diabetes Mellitus and Review of Published Case Reports

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.

Case for diagnosis. Ulcer and papular lesions in a patient with diabete mellitus. Protothecosis

Protothecosis is a rare disease caused by achlorophilic algae of the genus Prototheca spp. In general, three clinical forms are observed: cutaneous, articular and systemic. The cutaneous form is the most common one. This study describes a patient with isolated erythematous papules and erythematous papular plaques in the scapular regions, with a previous histopathological diagnosis of cryptococcosis. New tests were conclusive for the diagnosis of protothecosis, caused by Prototheca wickerhamii.

Lethal systemic and brain infection caused by Prototheca zopfii algae in a patient with acute myeloid leukemia

Systemic protothecosis is an exceptionally rare cause of sepsis with few available therapeutic options. Here, we report on a female patient with newly diagnosed acute myeloid leukemia who died after start of chemotherapy due to a severe septic shock caused by a disseminated systemic infection with Prototheca zopfii including encephalitis.

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.

cytb as a New Genetic Marker for Differentiation of Prototheca Species

Achlorophyllous unicellular microalgae of the genus Prototheca (Trebouxiophyceae, Chlorophyta) are the only known plants that cause infections in both humans and animals, collectively referred to as protothecosis. Human protothecosis, most commonly manifested as cutaneous, articular, and disseminated disease, is primarily caused by Protothecawickerhamii, followed by Protothecazopfii and, sporadically, by Protothecacutis and Protothecamiyajii In veterinary medicine, however, P. zopfii is a major pathogen responsible for bovine mastitis, which is a predominant form of protothecal disease in animals. Historically, identification of Prototheca spp. has relied upon phenotypic criteria; these were later replaced by molecular typing schemes, including DNA sequencing. However, the molecular markers interrogated so far, mostly located in the ribosomal DNA (rDNA) cluster, do not provide sufficient discriminatory power to distinguish among all Prototheca spp. currently recognized. Our study is the first attempt to develop a fast, reliable, and specific molecular method allowing identification of all Prototheca spp. We propose the mitochondrial cytb gene as a new and robust marker for diagnostics and phylogenetic studies of the Prototheca algae. The cytb gene displayed important advantages over the rDNA markers. Not only did the cytb gene have the highest discriminatory capacity for resolving all Prototheca species, but it also performed best in terms of technical feasibility, understood as ease of amplification, sequencing, and multiple alignment analysis. Based on the species-specific polymorphisms in the partial cytb gene, we developed a fast and straightforward PCR-restriction fragment length polymorphism (RFLP) assay for identification and differentiation of all Prototheca species described so far. The newly proposed method is advocated to be a new gold standard in diagnostics of protothecal infections in human and animal populations.

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.

[A case of cutaneous protothecosis]

The paper describes a case of a rare opportunistic infection, such as skin lesion caused by achlorophyllic unicellular algae of the genus Prototheca. It provides a detailed pathologic description of the foci of cutaneous protothecosis, such as pandermal inflammatory infiltrate, granulomas, pseudoepitheliomatous hyperplasia, and intraepidermal abscesses. Criteria for pathogen detection in histological sections are given.

Successful treatment of cutaneous protothecosis with liposomal amphotericin and oral itraconazole

Protothecosis is a rare algal infection, affecting primarily immunocompromised hosts. Optimal management is unclear: in-vitro antimicrobial breakpoints are not established and therapeutic decisions are primarily based on case reports. We present a case of cutaneous Prototheca wickerhamii infection in an immunosuppressed 63 year old male, successfully treated with liposomal amphotericin and prolonged itraconazole. Inoculation may have been through frequent hot-tub use, highlighting hot-tub exposure as an infection risk for the immunocompromised host.

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.

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.