Strongyloides stercoralis hyperinfection: an unusual cause of gastrointestinal bleeding

Hiperinfecção por Strongyloides stercoralis: uma causa incomum de hemorragia digestiva

Summary

Strongyloidiasis is a parasitic disease that may progress to a disseminated form, called hyperinfection syndrome, in patients with immunosuppression. The hyperinfection syndrome is caused by the wide multiplication and migration of infective larvae, with characteristic gastrointestinal and/or pulmonary involvement. This disease may pose a diagnostic challenge, as it presents with nonspecific findings on endoscopy.

Keywords:
gastrointestinal hemorrhage; gastrointestinal endoscopy; parasitic diseases; Strongyloides stercoralis

Resumo

Hiperinfecção por Strongyloides stercoralis: uma causa incomum de hemorragia digestiva A estrongiloidíase é uma parasitose que pode evoluir para uma forma disseminada, denominada síndrome de hiperinfecção, nos pacientes em estados de imunossupressão. A síndrome de hiperinfecção é ocasionada pela grande multiplicação e migração de larvas infectantes, com envolvimento gastrointestinal e/ou pulmonar característico. Essa doença pode representar um desafio diagnóstico, pois apresenta- se em achados inespecíficos à endoscopia.

Palavras-chave:
hemorragia gastrointestinal; endoscopia gastrointestinal; doenças parasitárias; Strongyloides stercolaris

Introduction

Strongyloides stercoralis is a parasite endemic of tropical and subtropical regions, with the capacity of completing its life cycle within its host through an auto-infective cycle. The low level of suspicion for the diagnosis of strongyloidiasis can lead physicians to miss or delay the final diagnosis.¹

Case report

A 76-year-old male, resident of São Paulo, Brazil, was referred to the hospital in May 2014, with a 2-month history of nausea, vomiting, anorexia, and 10-lb weight loss. Past medical history of metastatic castration-resistant prostate cancer, with recent palliative treatment with chemotherapy, and corticosteroids.

Laboratory tests during admission revealed mild anemia (hemoglobin: 11.1 mg/dL), normal total leukocyte count, normal peripheral blood eosinophil count and an increased C-reactive protein. Upper gastrointestinal endoscopy (UGE) showed gastric mucosal erythema, areas of atrophy, intestinal metaplasia, and pyloric stenosis due to cicatricial retraction. Duodenal mucosa presented a crispy surface with enlarged and rigid villosities, diffuse erythema, edema and friability (Figures 1 and 2). Biopsy from duodenum revealed larval form of Strongyloides stercoralis in mucosal crypts (Figure 3). Patient was treated with ivermectin for 2 days, and with high doses of proton pump inhibitors (PPI).

FIGURE 1
Severe bulbo-duodenitis with mild diffuse bleeding.

FIGURE 2
At close inspection with narrow-band imaging (NBI), enlarged and rigid duodenal villosities are seen.

FIGURE 3
Duodenal biopsy showing Strongyloides stercoralis larval infection in the mucosal crypts (arrow) (HE).

During hospitalization, he presented massive melena and hemorrhagic shock. Fluids and blood transfusion were started. UGE repeated during the gastrointestinal bleeding showed diffuse hemorrhagic duodenitis and bleeding erosions, which were endoscopically treated with argon plasma coagulation and hemoclips. Patient died after 11 days of hospitalization from Strongyloides stercoralis hyperinfection syndrome and sepsis.

Discussion

Strongyloidiasis is often an asymptomatic infection of upper small intestine. Immunosuppression may lead to hyperinfection with dissemination of S. stercoralis to almost all organs, with bacterial sepsis.² The hyperinfection syndrome is frequently associated with corticosteroid administration, and other immunosuppressive conditions, such as malignancies.³ This disease is potentially lethal, with mortality rates up to 87%, and it is characterized by gastrointestinal and/or pulmonary involvement.⁴Clinical manifestations of gastrointestinal impairment include abdominal pain, diarrhea, bleeding, nausea and vomiting. Diagnosis is challenging due to non-specific clinical features, and can be done by biopsy of suspicious changes at upper endoscopy.⁵

• Study conducted at Instituto do Câncer de São Paulo (ICESP), Faculdade de Medicina, Universidade de São Paulo (USP), São Paulo, SP, Brazil

References

• ¹
  Agrawal V, Agarwal T, Ghoshal UC. Intestinal strongyloidiasis: a diagnosis frequently missed in the tropics. Trans R Soc Trop Med Hyg. 2009; 103(3):242-6.
• ²
  Lim S, Katz K, Krajden S, Fuksa M, Keystone JS, Kain KC. Complicated and fatal Strongyloides infection in Canadians: risk factors, diagnosis and management. CMAJ. 2004; 171(5):479-84.
• ³
  Machado ER, Teixeira EM, Gonçalves-Pires MDRF, Loureiro ZM, Araújo RA, Costa-Cruz JM. Parasitological and immunological diagnosis of Strongyloides stercoralis in patients with gastrointestinal cancer. Scand J Infect Dis. 2008; 40(2):154-8.
• ⁴
  Marcos LA, Terashima A, Dupont HL, Gotuzzo E. Strongyloides hyperinfection syndrome: an emerging global infectious disease. Trans R Soc Trop Med Hyg. 2008; 102(4):314-8.
• ⁵
  Keiser PB, Nutman TB. Strongyloides stercoralis in the immunocompromised population. Clin Microbiol Rev. 2004; 17(1):208-17.

Publication Dates

• Publication in this collection
  Jul-Aug 2015

History

• Received
  04 Sept 2014
• Accepted
  09 Sept 2014