Protothecosis in hematopoietic stem cell transplantation: case report and review of previous cases

Abstract

Prototheca species are achlorophyllus algae. Prototheca wickerhamii and Prototheca zopfii cause human disease. In immunocompetent individuals, they cause soft tissue infections and olecranon bursitis, but in transplant recipients, these organisms can cause disseminated disease. We report a fatal case of disseminated P. zopfii infection in an hematopoietic stem cell transplant (HSCT) recipient with bloodstream infection and involvement of multiple soft tissue sites. We review all previous cases of protothecosis in HSCT reported in the literature. Protothecosis is uncommon after HSCT, but has a disseminated presentation that is frequently fatal. It is commonly misidentified as a yeast. Tumor necrosis factor-alpha inhibitors and contamination of central venous catheters may contribute to development of protothecosis. Optimal treatment approaches are yet to be defined. New agents such as miltefosine may be possible future therapies.

Prototheca wickerhamii algaemia: an emerging infection in solid organ transplant recipients

“…Manufacturers continue to expand the reference databases, improving the limitations of this technology . The initial failed identification in our case, and in a prior report , likely reflects the absence of representative reference spectra for certain species isolates, protein variability among strains, or the nature of the organism, and the extraction method used to reveal its protein milieu. The forces required to produce efficient breakage of the organisms may be comparable to those required for organisms with lipid‐rich waxy cell wall, such as Mycobacteria , because Prototheca species contain a rigid wall with high tensile strength and several thick‐walled autospores .…”

“…Other medications, such as tetracycline, aminoglycoside, echinocandin, terbinafine, and polymyxin, used alone or in combination, had mixed results . Miltefosine, an alkylphosphocholine drug used for leishmaniasis and salvage therapy for fungal infection, has in vitro activity against P. zopfii ; hence, it could be a potential treatment option for protothecosis but remains to be evaluated in clinical practice .…”

Successful treatment of cutaneous protothecosis with liposomal amphotericin and oral itraconazole

“…A wide range of systemic manifestations has been reported, including abdominal infections, pneumonia, bloodstream infection and central nervous system infection [2] , [9] , [10] , [11] . Peritoneal catheter and other device infections are also described [2] , [12] , [13] . Disseminated disease is reported generally in the immunosuppressed, frequently with exogenous steroid use, as with this case [2] .…”

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

“…Although numerous cases of Prototheca infection in immunocompetent hosts with or without a history of trauma have been reported , immunosuppression is increasingly recognized as a risk factor, as it has been reported in patients with acquired immunodeficiency syndrome (AIDS) , diabetes mellitus , chronic steroid use , steroid and cyclosporine use for myasthenia gravis , belimumab and rituximab use for systemic lupus erythematous , chemotherapy for solid or hematologic malignancy , hematopoietic stem cell transplantation (HSCT) and solid organ transplantation , and infliximab therapy for graft‐versus‐host disease after HSCT . A case of breakthrough protothecosis during long‐term voriconazole therapy for pulmonary aspergillosis after HSCT was also reported .…”