[Spinal cord histoplasmoma. A case report]

Abstract

Over a period of 2 months, a 60-year-old man, a chicken breeder, experienced low back pain, lower limb weakness predominant on the right side, and urinary difficulties, leading progressively to a flaccid paraplegia with sphincter impairment. Concomitant poor cognitive performances were noted. MRI showed enlargement of the conus terminalis, with a low-intensity signal on T1-weighted images, high-intensity signal on T2-weighted images, and areas of intramedullar contrast enhancement. A biopsy of the lesion showed macrophages containing yeast cells, with PAS and Grocott staining aspects compatible with the presence of Histoplasma capsulatum (Hc). A brain MRI showed multiple localizations in the brain stem and in both hemispheres with associated edema. Disseminated histoplasmosis was confirmed by a biopsy of a sub-maxillary ganglion demonstrating a necrotic tuberculoid lymphadenitis containing yeast cells resembling Hc. Immune tests disclosed the presence of HTLV1 anti-bodies without immunodeficiency nor HIV co-infection. An anti-micotic treatment was started 2 weeks after surgery, with intra-venous amphotericin B, for 21 days, followed by itraconazole, orally for 90 days. Cognitive functions improved significantly in 5 weeks while paraplegia and sphincter impairment remained unchanged. Seven months later, cerebral MR aspects dramatically improved while the conus medullaris lesion diminished, and the edematous component disappeared in all areas. Even though histoplasmosis is endemic in our region, CNS localization is rare, generally in disseminated forms associated with immunodeficiency. Brain granulomas are well-known, but spinal cord histoplasmomas are exceptional: only four cases have been evaluated by MRI. Unlike our case, spinal cord forms generally improve, due to surgery associated with antifungus medication, or sometimes due to specific medical treatment alone but with sufficient dosage.