Strongyloides stercoralis Infection in a Patient with Chronic Renal Failure from North China.

Introduction: Human strongyloidiasis is a generally neglected parasitic disease of major global distribution, spreading commonly in tropical and subtropical areas. As for China, strongyloidiasis occur mainly in South of China and no relevant information about the parasite infection in North China was available.

Case Presentation: An 84-year-old man from Shanxi province, North China, was admitted to Department of Nephrology with complaints of a 7-month history of intermittent edema of both lower extremity with foam urine and 3-day history of fever, chill and diarrhea. Large numbers of rhabditiform larva of Strongyloides stercoralis (S. stercoralis) were observed in a stool sample. Diagnosis of S. stercoralis infection was established by morphological observations of larvae under the microscope in both wet mount and Wright-Giemsa staining smear and further confirmed by molecular biology identification.

Conclusions: We report a rare case of S. stercoralis infection in a patient with chronic renal failure from North China, which implies the possibility of developing human strongyloidiasis in cooler climates. In addition, our case suggests that clinicians should consider the complication of S. stercoralis infection in immunosuppressed patient populations with chronic renal failure. Morphological details of S. stercoralis in Wright-Giemsa staining was first described in the present case. Our results also support the use of molecular techniques targeting COX1 gene sequence for the diagnosis of S. stercoralis infection, which was prove to be necessary in laboratory practice, especially for those inexperienced morphologists in temperature zone.