The clinical spectrum of bulbar conjunctival rhinosporidiosis

Abstract

Purpose: To report the clinical spectrum of bulbar conjunctival rhinosporidiosis at a tertiary eye care oculoplastics facility.

Methods: Retrospective chart review of biopsy-proven ocular and adnexal rhinosporidiosis over a five-year period (2017-2022). Demographic details, clinical presentation, management interventions, and outcomes in a series of cases with bulbar conjunctival rhinosporidiosis were documented and analyzed.

Results: A total of 14 cases of biopsy-proven bulbar conjunctival rhinosporidiosis were included in this study. These formed 22.2% of all cases of ocular adnexal rhinosporidiosis and 46.7% of all conjunctival cases diagnosed within the study period. All the cases underwent surgical excision of the conjunctival mass with five (35.7%) requiring a scleral patch graft for scleral thinning with or without staphyloma formation. Most patients had a good outcome on medium to long-term follow-up.

Conclusions: Even though tarsal conjunctival involvement is reported as the most common form of conjunctival rhinosporidiosis in the literature, in our series, bulbar conjunctival disease comprised nearly half of all conjunctival cases, and over 20% of all adnexal cases. Most appear to do well with complete surgical excision of the granuloma. Rarely, long-standing cases may develop scleral thinning with or without staphyloma formation which may need major tectonic support to protect the integrity of the eyeball. Most of these also appear to do well on medium to long-term follow-up.

Keywords: Bulbar; conjunctival; rhinosporidiosis.

Figure 1

External photograph of the left eye showing a pinkish-brown soft tissue mass nasally (a) that revealed an edematous hyperreflective conjunctival epithelium and stroma, multiple small hyporeflective spots (blood vessels) scattered throughout the stromal tissue suggestive of the highly vascular nature of the lesion, and variable sized hyperreflective dots representing multiple sporangia-containing spherules of Rhinosporidium seeberi on AS-OCT (b). Histopathological sections stained with hematoxylin-eosin (H and E, x20) (c) and Gomori-methenamine-silver (GMS, x20) (d), show edematous epithelial and stromal tissue with an inflammatory infiltrate and multiple thick-walled sporangia with endospores at different stages of maturation

Figure 2

Different clinical presentations of bulbar conjunctival rhinosporidiosis – sessile lesion simulating a pyogenic granuloma of the ocular surface (a); temporally located granuloma simulating ocular surface squamous neoplasia, especially with the prominent feeder vessel superiorly (b); large granuloma on the medial bulbar conjunctiva completely obscuring the caruncle and the plica (c); chronic infection resulting in focal scleral thinning with uveal show and an absent granuloma (d). Lesions in (a), (b), and (c) show typical whitish specks on the surface while in D, these were extremely subtle and located deep in the lower fornix seen only at surgery under high magnification of the operating microscope

Figure 3

Scleral thinning with early staphylomatous bulge seen in a case of long-standing bulbar conjunctival rhinosporidiosis (a) managed with tectonic support by a scleral patch graft that is stable and well taken at two years post-surgery (b), and a large superiorly located focus of scleromalacia perforans simulating necrotizing scleritis with an adjacent inferior conjunctival granuloma (c) also managed with an appropriately-sized scleral patch graft seen at the two-week postoperative follow-up (d) providing the necessary tectonic support to preserve globe integrity