Rhinosporidiosis

Back

Background

Rhinosporidiosis is a chronic granulomatous infection of the mucous membranes that usually manifests as vascular friable polyps that arise from the nasal mucosa or external structures of the eye.



View Image

Granulomatous mass involving structures of the eye. Image used with permission from doctorfungus.org.

Initially described by Seeber in 1900 in an individual from Argentina,[1] rhinosporidiosis is endemic in India, Sri Lanka, South America, and Africa.[2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14] Cases from the United States and Southeast Asia, as well as scattered occurrences throughout the world, have also been reported. Most cases of rhinosporidiosis occur in persons from or residing in the Indian subcontinent or Sri Lanka. In addition to humans, rhinosporidiosis has been noted in cats, cattle, dogs, ducks, goats, horses, mules, parrots, and swan.[15]

The etiologic agent, Rhinosporidium seeberi, has never been successfully propagated in vitro. Initially thought to be a parasite, for more than 50 years R seeberi had been considered to be a water mold.[16] Molecular biological techniques have more recently demonstrated this organism to be an aquatic protistan parasite, and it has been placed into a new class, the Mesomycetozoea, along with organisms that cause similar infections in amphibians and fish.[17, 18, 19] This reclassification is not without controversy, as other researchers have presented data that R seeberi is a cyanobacterium, further demonstrating the difficulties that arise when working with pathogens that cannot be maintained in the laboratory setting.[20, 21] Other molecular work has demonstrated evidence that R seeberi may have host-specific strains (eg, human vs dog vs swan).[22]

Pathophysiology

Rhinosporidiosis is an infection that is typically limited to the mucosal epithelium. Infection usually results from a local traumatic inoculation with the organism. The disease progresses with the local replication of R seeberi and associated hyperplastic growth of host tissue and a localized immune response.

Infection of the nose and nasopharynx is observed in 70% of persons with rhinosporidiosis; infection of the palpebral conjunctivae or associated structures (including the lacrimal apparatus) is observed in 15%.[23]

Other structures of the mouth, upper airway, and eye may be sites of disease. Disease of the skin, ear, larynx, trachea, bronchi, genitals, and rectum has also been described.[24] Genital rhinosporidiosis has been described in the vagina, penile urethra or meatus, and scrotum.[25] Dissemination with cutaneous and multisite disease is also reported, but this is much less common. Isolated cases of dissemination involving deep organs have been rarely reported.[26, 27]

Epidemiology

Frequency

United States

Rhinosporidiosis cases in the United States are rare but are more common in Texas and the Southeast.

International

Rhinosporidiosis usually affects persons in or from southern India and Sri Lanka. Cases have been reported worldwide, with an increased incidence in South America and Africa.

Mortality/Morbidity

Rhinosporidiosis can cause prolonged painless disease with limited morbidity. Disease of up to 30 years' duration has been reported. Secondary bacterial infection can cause morbidity. Death has been reported in only the few rare reports of disseminated rhinosporidiosis.

Race

Rhinosporidiosis has no known racial predilection.

Sex

Men are affected more commonly than women, with a male-to-female ratio of 4:1.

Age

Rhinosporidiosis most commonly occurs in children and in individuals aged 15-40 years.

Risk Factors

Rhinosporidiosis has been associated with rural residence, occupation in farming or agriculture, and bathing in ponds or rivers.[28, 29, 30]

Prognosis

The prognosis of rhinosporidiosis is excellent, except with dissemination, as described above (see Mortality/Morbidity).

Patient Education

Patients with rhinosporidiosis should be advised that recurrence is possible. They should be instructed to return for further evaluation if symptoms recur or new symptoms arise.

Cases of dissemination or more extensive disease have been associated with a prior history of both treated and untreated nasal disease. Accordingly, ensure that patients are instructed to (1) be vigilant for a recurrence of symptoms or new lesions and (2) promptly consult with their physician if these are noted.

History

Nasal rhinosporidiosis may present with unilateral nasal obstruction or epistaxis. Other symptoms may include local pruritus, coryza with sneezing, rhinorrhea, and postnasal discharge (drip) with cough. Patients often report a sensation that a foreign body is present in their nasal canal.

Eye involvement is initially asymptomatic. Increased tearing may be reported as the disease progresses. Photophobia, redness, and secondary infection may occur.

Skin lesions begin as papillomas that gradually become verrucous.

Physical

Soft polyps may develop on the nose or eye. These polyps are pink to deep red, are sessile or pedunculated, and are often described as strawberrylike in appearance. Because the polyps of rhinosporidiosis are vascular and friable, they bleed easily upon manipulation. This appearance results from sporangia, which are visible as gray or yellow spots in the vascular polypoid masses.

Causes

The etiologic agent of rhinosporidiosis, R seeberi, has traditionally been considered a fungus. Recent 18S ribosomal ribonucleic acid (rRNA) gene analysis has placed R seeberi into a novel group of aquatic parasites of the class Mesomycetozoea, some of which cause similar diseases in amphibians and fish.[17, 18, 19]

Most persons with rhinosporidiosis have had bathing or working exposure to stagnant water.[6, 31]

No immune deficiency has been associated with infection.

Complications

Complications of rhinosporidiosis include extremely rare, life-threatening dissemination, local secondary bacterial infection, and recurrence.

Laboratory Studies

Direct observation

Rhinosporidiosis is diagnosed by identifying the typical structures of R seeberi directly on microscopic examination. This includes examination of smears of macerated tissue or histology of prepared biopsy sample sections.

The organism can be observed with typical fungal stains (eg, Gomori methenamine silver [GMS], periodic acid-Schiff [PAS]), as well as with standard hematoxylin and eosin (H&E) staining.

Smears can also be observed with potassium hydroxide (KOH) preparation.

Serologic testing

Serologic testing (immunoblot (dot – enzyme-linked immunosorbent assay [ELISA]) identification of antirhinosporidial antibody) has been developed and used for epidemiologic studies in endemic areas, but this testing is not available for or routinely used in patient diagnosis.[32, 31]

Imaging Studies

Recent evaluation of the use of computed tomography (CT) imaging to delineate the site and extent of disease has been published.[33] Moderate-to-intense enhancement by CT was noted in the majority of lesions in the 16 people included in that study.

Histologic Findings

In 1923, Ashworth described in detail the life cycle of the organism in tissue.[16] This cycle begins with a round endospore that is 6-10 µm in diameter. The endospore grows to become a thick-walled sporangium of 100-350 µm in diameter that contains up to several thousand endospores. These structures are similar to the smaller endospores (2-5 µm in diameter) and spherules (30-60 µm in diameter) of Coccidioides immitis.

The sporangia of R seeberi are observed under the normal epithelium. They are associated with immune cells, including neutrophils, lymphocytes, plasma cells, and multinucleated giant cells, often in scattered granuloma. Papillomatous hyperplasia and hypervascularity are also common. See the images below.



View Image

Sporangia of Rhinosporidium seeberi within nasal polyp (periodic acid-Schiff [PAS] stain). Image used with permission from doctorfungus.org.



View Image

Sporangia of Rhinosporidium seeberi in polyp (Gomori methenamine silver [GMS]) stain. Image used with permission from doctorfungus.org.

Medical Care

Rhinosporidiosis is treated with surgical excision because, generally, medical treatment has not been proven effective. However, multiple reports of successful treatment of individuals with long courses of dapsone have been published.[34, 35] This drug may be useful in individuals with multisite rhinosporidiosis.

Surgical Care

Local surgical excision is the treatment of choice for rhinosporidiosis. Recurrence has been reported with simple excision. Wide excision with electrocoagulation of the lesional base has been promoted to decrease recurrences.

Author

Duane R Hospenthal, MD, PhD, FACP, FIDSA, FASTMH, Physician, San Antonio Infectious Diseases Consultants; Adjunct Professor of Medicine, Department of Medicine, University of Texas Health Science Center at San Antonio

Disclosure: Nothing to disclose.

Specialty Editors

Francisco Talavera, PharmD, PhD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Thomas M Kerkering, MD, Chief of Infectious Diseases, Virginia Tech Carilion School of Medicine

Disclosure: Nothing to disclose.

Chief Editor

Pranatharthi Haran Chandrasekar, MBBS, MD, Professor, Chief of Infectious Disease, Department of Internal Medicine, Wayne State University School of Medicine

Disclosure: Nothing to disclose.

Additional Contributors

Gary L Gorby, MD, Associate Professor, Departments of Internal Medicine and Medical Microbiology and Immunology, Division of Infectious Diseases, Creighton University School of Medicine; Associate Professor of Medicine, University of Nebraska Medical Center; Associate Chair, Omaha Veterans Affairs Medical Center

Disclosure: Nothing to disclose.

Acknowledgements

Robert Rivard, MD Deputy Chief, Department of Clinical Research

Robert Rivard, MD is a member of the following medical societies: American College of Physicians, American Medical Association, Armed Forces Infectious Diseases Society, and Infectious Diseases Society of America

Disclosure: Nothing to disclose.

References

  1. Seeber GR. Un neuvo esporozoario parasito del hombre: dos casos encontrades en polipos nasales. Thesis, Universidad Nacional de Buenos Aires. 1900.
  2. Capoor MR, Khanna G, Rajni, Batra K, Nair D, Venkatchalam VP, et al. Rhinosporidiosis in Delhi, north India: case series from a non-endemic area and mini-review. Mycopathologia. 2009 Aug. 168(2):89-94. [View Abstract]
  3. Gaines JJ Jr, Clay JR, Chandler FW, Powell ME, Sheffield PA, Keller AP 3rd. Rhinosporidiosis: three domestic cases. South Med J. 1996 Jan. 89(1):65-7. [View Abstract]
  4. Hospenthal DR. Uncommon Fungi and Related Species. Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 8th ed. Philadelphia, Pa: Elsevier Saunders; 2015. 3003-3015.
  5. Hospenthal DR. Entomophthoramycosis, Lobomycosis, Rhinosporidiosis, and Sporotrichosis. Guerrant RL, Walker DH, Weller PF, eds. Tropical Infectious Diseases. Principles, Pathogens, & Practice. 3rd. Philadelphia, Pa: Saunders Elsevier; 2011. 603-607.
  6. Karunaratne WAE. Rhinosporidiosis in Man. London, England: The Athlone Press; 1964.
  7. Kwon-Chung KJ, Bennett JE. Rhinosporidiosis. Medical Mycology. Philadelphia, Pa: Lea & Febiger; 1992. 695-706.
  8. Mohan H, Chander J, Dhir R, Singhal U. Rhinosporidiosis in India: a case report and review of literature. Mycoses. 1995 May-Jun. 38(5-6):223-5. [View Abstract]
  9. Moses JS, Shanmugham A, Kingsly N, et al. Epidemiological survey of rhinosporidiosis in Kanyakumari district of Tamil Nadu. Mycopathologia. 1988 Mar. 101(3):177-9. [View Abstract]
  10. Rippon JW. Rhinosporidiosis. Medical Mycology. The Pathogenic Fungi and the Pathogenic Actinomycetes. 3rd ed. Philadelphia, Pa: WB Saunders Co; 1988. 362-72.
  11. Satyanarayana C. Rhinosporidiosis with a record of 255 cases. Acta Otolaryngol. 1960 Mar. 51:348-66. [View Abstract]
  12. Das S, Kashyap B, Barua M, Gupta N, Saha R, Vaid L. Nasal rhinosporidiosis in humans: new interpretations and a review of the literature of this enigmatic disease. Med Mycol. 2011 Apr. 49(3):311-5. [View Abstract]
  13. Almeida FA, Feitoza Lde M, Pinho JD, Mello GC, Lages JS, Silva FF, et al. Rhinosporidiosis: the largest case series in Brazil. Rev Soc Bras Med Trop. 2016 Jul-Aug. 49 (4):473-6. [View Abstract]
  14. Vélez A, Jiménez G, Hidrón A, Talero S, Agudelo CA. Rhinosporidiosis in Colombia: case series and literature review. Trop Doct. 2018 Oct. 48 (4):289-293. [View Abstract]
  15. Kennedy FA, Buggage RR, Ajello L. Rhinosporidiosis: a description of an unprecedented outbreak in captive swans (Cygnus spp.) and a proposal for revision of the ontogenic nomenclature of Rhinosporidium seeberi. J Med Vet Mycol. 1995 May-Jun. 33(3):157-65. [View Abstract]
  16. Ashworth JH. On Rhinosporidium seeberi (Wernicke 1903) with special reference to its sporulation and affinities. Trans R Soc Edinburgh. 1923. 53:301-342.
  17. Fredricks DN, Jolley JA, Lepp PW, Kosek JC, Relman DA. Rhinosporidium seeberi: a human pathogen from a novel group of aquatic protistan parasites. Emerg Infect Dis. 2000 May-Jun. 6(3):273-82. [View Abstract]
  18. Herr RA, Ajello L, Taylor JW, Arseculeratne SN, Mendoza L. Phylogenetic analysis of Rhinosporidium seeberi's 18S small-subunit ribosomal DNA groups this pathogen among members of the protoctistan Mesomycetozoa clade. J Clin Microbiol. 1999 Sep. 37(9):2750-4. [View Abstract]
  19. Mendoza L, Taylor JW, Ajello L. The class mesomycetozoea: a heterogeneous group of microorganisms at the animal-fungal boundary. Annu Rev Microbiol. 2002. 56:315-44. [View Abstract]
  20. Ahluwalia KB, Dhaulakhandi DB, Garg LC. Sequence analysis of 16S rRNA gene inRhinosporidium seeberi shows similarity to plant chloroplast DNA. Bioinformation. 2010 Sep 20. 5(3):89-96. [View Abstract]
  21. Vilela R, Mendoza L. The taxonomy and phylogenetics of the human and animal pathogen Rhinosporidium seeberi: A critical review. Rev Iberoam Micol. 2012 Apr 12. [View Abstract]
  22. Silva V, Pereira CN, Ajello L, Mendoza L. Molecular evidence for multiple host-specific strains in the genus Rhinosporidium. J Clin Microbiol. 2005 Apr. 43(4):1865-8. [View Abstract]
  23. Pushker N, Kashyap S, Bajaj MS, Meel R, Sood A, Sharma S, et al. Primary lacrimal sac rhinosporidiosis with grossly dilated sac and nasolacrimal duct. Ophthal Plast Reconstr Surg. 2009 May-Jun. 25(3):234-5. [View Abstract]
  24. Deshpande AH, Agarwal S, Kelkar AA. Primary cutaneous rhinosporidiosis diagnosed on FNAC: a case report with review of literature. Diagn Cytopathol. 2009 Feb. 37(2):125-7. [View Abstract]
  25. Sasidharan K, Subramonian P, Moni VN, Aravindan KP, Chally R. Urethral rhinosporidiosis. Analysis of 27 cases. Br J Urol. 1987 Jan. 59(1):66-9. [View Abstract]
  26. Agrawal S, Sharma KD, Shrivastava JB. Generalized rhinosporidiosis with visceral involvement; report of a case. AMA Arch Derm. 1959 Jul. 80(1):22-6. [View Abstract]
  27. Adiga BK, Singh N, Arora VK, Bhatia A, Jain AK. Rhinosporidiosis. Report of a case with an unusual presentation with bony involvement. Acta Cytol. 1997 May-Jun. 41(3):889-91. [View Abstract]
  28. Dutta S, Haldar D, Dutta M, Barik S, Das Biswas K, Sinha R. Socio-demographic Correlates of Rhinosporidiosis: A Hospital-Based Epidemiologic Study in Purulia, India. Indian J Otolaryngol Head Neck Surg. 2017 Mar. 69 (1):108-112. [View Abstract]
  29. Almeida FA, Feitoza Lde M, Pinho JD, Mello GC, Lages JS, Silva FF, et al. Rhinosporidiosis: the largest case series in Brazil. Rev Soc Bras Med Trop. 2016 Jul-Aug. 49 (4):473-6. [View Abstract]
  30. Karthikeyan P, Vijayasundaram S, Pulimoottil DT. A Retrospective Epidemiological Study of Rhinosporidiosis in a Rural Tertiary Care Centre in Pondicherry. J Clin Diagn Res. 2016 May. 10 (5):MC04-8. [View Abstract]
  31. Arseculeratne SN, Sumathipala S, Eriyagama NB. Patterns of rhinosporidiosis in Sri Lanka: comparison with international data. Southeast Asian J Trop Med Public Health. 2010 Jan. 41(1):175-91. [View Abstract]
  32. Sudasinghe T, Rajapakse RP, Perera NA, Kumarasiri PV, Eriyagama NB, Arseculeratne SN. The regional sero-epidemiology of rhinosporidiosis in Sri Lankan humans and animals. Acta Trop. 2011 Oct-Nov. 120(1-2):72-81. [View Abstract]
  33. Prabhu SM, Irodi A, Khiangte HL, Rupa V, Naina P. Imaging features of rhinosporidiosis on contrast CT. Indian J Radiol Imaging. 2013 Jul. 23(3):212-8. [View Abstract]
  34. Job A, Venkateswaran S, Mathan M, Krishnaswami H, Raman R. Medical therapy of rhinosporidiosis with dapsone. J Laryngol Otol. 1993 Sep. 107(9):809-12. [View Abstract]
  35. Madke B, Mahajan S, Kharkar V, Chikhalkar S, Khopkar U. Disseminated cutaneous with nasopharyngeal rhinosporidiosis: Light microscopy changes following dapsone therapy. Australas J Dermatol. 2011 May. 52(2):e4-6. [View Abstract]
  36. Prasad V, Shenoy VS, Rao RA, Kamath PM, Rao KS. Rhinosporidiosis: A Chronic Tropical Disease in Lateral Pharyngeal Wall. J Clin Diagn Res. 2015 May. 9 (5):MD01-2. [View Abstract]

Granulomatous mass involving structures of the eye. Image used with permission from doctorfungus.org.

Sporangia of Rhinosporidium seeberi within nasal polyp (periodic acid-Schiff [PAS] stain). Image used with permission from doctorfungus.org.

Sporangia of Rhinosporidium seeberi in polyp (Gomori methenamine silver [GMS]) stain. Image used with permission from doctorfungus.org.

Granulomatous mass involving structures of the eye. Image used with permission from doctorfungus.org.

Sporangia of Rhinosporidium seeberi within nasal polyp (periodic acid-Schiff [PAS] stain). Image used with permission from doctorfungus.org.

Sporangia of Rhinosporidium seeberi in polyp (Gomori methenamine silver [GMS]) stain. Image used with permission from doctorfungus.org.