Fatal Cokeromyces recurvatus Pneumonia: Report of a Case Highlighting the Potential for Histopathologic Misdiagnosis as Coccidioides

Abstract

Cokeromyces recurvatus is a dimorphic zygomycete with histologic morphology similar to Coccidioides immitis. A 66-year-old man who was status-post bone marrow transplantation for chronic myelogenous leukemia was hospitalized with new onset rash, nausea, and vomiting and subsequently expired. A sputum culture collected on the day of death revealed heavy growth of C. recurvatus 6 days after collection. At autopsy, microscopic examination of the lungs revealed numerous thick-walled, nonbudding spherules ranging in size from 40 to 80 µm. Initial immunohistochemical staining of the formalin-fixed lung tissue was positive for Coccidioides. Additional immunoperoxidase staining revealed the organisms were consistent with a zygomycete fungus, compatible with C. recurvatus infection. Polymerase chain reaction using panfungal primers was attempted on the formalin-fixed tissue but was inconclusive. This case highlights the potential for misdiagnosing Cokeromyces as Coccidioides when the diagnosis is based on histology and immunohistochemical staining.

Mucormycosis Caused by Unusual Mucormycetes, Non-Rhizopus, -Mucor, and -Lichtheimia Species

“…Also, yeast-like cells were observed in secretions from six of the patients with possible or probable infection or colonization (15,23,151,270,284,335) and from tissue sections in three cases (15,293,335). However, histological evidence of C. recurvatus infection with invasion of lung tissue by yeast-like cells and pseudohyphae has been described in only one case (293).…”

“…C. recurvatus has been recovered from peritoneal fluid after viscus perforation secondary to intestinal lymphosarcoma in a cat (226). Only eight cases of human C. recurvatus infection (293), probable (23,270) or possible (15,210,219,335) disease, or colonization (151,284) have been reported in the literature. The species was first isolated by Shanor et al (309) in 1950.…”

“…This fungus has been isolated from vaginal secretions (151,210,284), stool (15,335), urine (23), sputum (293), pleural and peritoneal fluids (219), and fluid from intra-abdominal abscesses (270). Also, yeast-like cells were observed in secretions from six of the patients with possible or probable infection or colonization (15,23,151,270,284,335) and from tissue sections in three cases (15,293,335). However, histological evidence of C. recurvatus infection with invasion of lung tissue by yeast-like cells and pseudohyphae has been described in only one case (293).…”

“…This patient had recurrent abdominal pain 10 months later, with C. recurvatus growing in his peritoneal fluid; he had a recovery with surgery and use of antifungal drugs (AmB and L-AmB in sequential therapy) (270). Therefore, three cases (23,270,293) met the criteria of this review for C. recurvatus infection.…”

“…C. recurvatus is a dimorphic Mucormycetes organism of the order Mucorales and family Thamnidiaceae that has been isolated only in North America (23,293,309), where it can be found in soils and the feces of lizards, certain rodents (23,226,279,293), and occasionally humans (151,284,293). C. recurvatus has been recovered from peritoneal fluid after viscus perforation secondary to intestinal lymphosarcoma in a cat (226).…”