A Rare Cause of Pedunculated Polyps Caused by Strongyloides
  • Omer Yousaf
    Norton Community Hospital, Ballad Health, Norton, VA, USA
  • Arisha Carreon
    Norton Community Hospital, Ballad Health, Norton, VA, USA
  • Ibrahim Mohsin
    Norton Community Hospital, Ballad Health, Norton, VA, USA


Colitis, pseudopolyposis, Strongyloides stercoralis, pedunculated polyps


Introduction: Strongyloidiasis is a systemic disease caused by the nematode Strongyloides stercoralis. Strongyloides is unique among parasites in that it can remain undetected for decades. Although patients may present with the typical symptoms of a skin rash, cough or diarrhoea, a rare manifestation of infection is pseudopolyposis in the colon. This case highlights the unique finding of pseudopolyposis in a patient with strongyloidiasis with negative stool studies.

Case description: We present the case of an 81-year-old man with a delayed diagnosis of strongyloidiasis. The patient initially presented to the clinic for evaluation of productive cough and was treated empirically for bronchitis. He subsequently developed vomiting and diarrhoea with imaging revealing circumferential wall thickening of the ascending colon, consistent with colitis. Although stool tests were negative, the patient was treated with antibiotics, and then underwent a colonoscopy which revealed multiple polyps. Biopsy results confirmed Strongyloides infection. The patient was treated with ivermectin and improved.

Discussion: This case describes the unique finding of colonic pseudopolyposis in a patient infected with Strongyloides in rural southwest Virginia. Strongyloidiasis is often misdiagnosed due to its non-specific gastrointestinal symptoms and the chronic nature of the disease. Although stool studies are routinely negative for parasitic infection, CT scan findings suggestive of colitis should be followed by colonoscopy with biopsy of any abnormal lesion in the right clinical context. Determining the definitive diagnosis in a timely manner is crucial for establishing the specific treatment and for resolution of the disease.



  • Montes M, Sawhney C, Barros N. Strongyloides stercoralis: there but not seen. Curr Opin Infect Dis 2010;23(5):500–504.
  • Porto MA, Alcântara LM, Leal M, Castro N, Carvalho EM. Atypical clinical presentation of strongyloidiasis in a patient co-infected with human T cell lymphotrophic virus type I. Am J Trop Med Hyg 2005;72(2):124–125.
  • Caumes E, Keystone JS. Acute strongyloidiasis: a rarity. Chronic strongyloidiasis: a time bomb! J Travel Med 2011;18(2):71–72.
  • Salvador F, Sulleiro E, Sánchez-Montalvá A, Saugar JM, Rodríguez E, Pahissa A, et al. Usefulness of Strongyloides stercoralis serology in the management of patients with eosinophilia. Am J Trop Med Hyg 2014;90:830–834.
  • Buonfrate D, Requena-Mendez A, Angheben A, Cinquini M, Cruciani M, Fittipaldo A, et al. Accuracy of molecular biology techniques for the diagnosis of Strongyloides stercoralis infection - a systematic review and meta-analysis. PLoS Negl Trop Dis 2018;12(2):e0006229.
  • Thompson BF, Fry LC, Wells CD, Olmos M, Lee DH, Lazenby AJ, et al. The spectrum of GI strongyloidiasis: an endoscopic-pathologic study. Gastrointest Endosc 2004;59(7):906–910.
  • Minematsu H, Hokama A, Makishi T, Arakaki K, Kinjo F, Fujita J. Colonoscopic findings and pathologic characteristics of Strongyloides colitis: a case series. Digestion 2011;83:210–214.
  • Ra H, Chung JW, Chung DH, Kim JH, Kim YJ, Kim KO, et al. Strongyloidiasis presenting as yellowish nodules in colonoscopy of an immunocompetent patient. Clin Endosc 2019;52(1):80–82.
  • Nam S, Han M, Kim Y, Kum Y, Suh I, Bae H. Two cases of strongyloidiasis diagnosed by colonoscopic biopsy. Korean J Pathol 2007;41:343–346.
  • Qu Z, Kundu UR, Abadeer RA, Wanger A. Strongyloides colitis is a lethal mimic of ulcerative colitis: the key morphologic differential diagnosis. Hum Pathol 2009;40(4):572–577.
  • Keiser PB, Nutman TB. Strongyloides stercoralis in the immunocompromised population. Clin Microbiol Rev 2004;17(1):208–217.
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    Published: 2022-03-03
    Issue: 2022: Vol 9 No 3 (view)

    How to cite:
    Yousaf O, Carreon A, Mohsin I. A Rare Cause of Pedunculated Polyps Caused by Strongyloides . EJCRIM 2022;9 doi:10.12890/2022_003008.

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