Asymptomatic Strongyloides stercoralis Hyperinfection in an Alcoholic Patient with Intense Anemia

Abstract

Strongyloides stercoralis infection is endemic in many tropical and subtropical areas. The parasite has the unusual ability to multiply inside the host due to the transformation of rhabditiform larvae into infective filariforms. Several studies have shown that chronic alcoholism is an important factor that predisposes to strongyloidiasis. The increased susceptibility to S. stercoralis infections seen in alcoholic individuals could be explained by their increased exposure to the parasite, malnutrition, breakdown of local immune responses, and/or alterations in intestinal barriers. Moreover, ethanol intoxication can elevate human endogenous corticosterone, which, in turn, suppresses T cell function and increases the fecundity and survival of the parasite, mimicking the effect of worm ecdysteroides. Although chronic alcoholism is a risk factor for nematode infection, most cases of hyperinfection or dissemination are associated with the presence of hepatic cirrhosis or strongyloidiasis-related symptoms. The present study describes a case of S. stercoralis hyperinfection in a 51-yr-old male patient without gastrointestinal or pulmonary symptoms and with previous anemia and chronic alcoholism. He was not receiving glucocorticoid therapy and tested negative for HTLV and human immunodeficiency virus (HIV), but he had a history of alcohol addiction for more than 20 yr. Laboratory test results showed increased eosinophilia and a high immunoglobulin E (IgE) level, which may have temporarily protected the patient from dissemination of infection, but not prevented proliferation of the parasite, as shown by the large number of S. stercoralis larvae recovered using the Baermann method. Evaluation for strongyloidiasis should occur in alcoholics, especially in endemic areas, to prevent occult asymptomatic infections from progressing to life-threatening cases.

Hookworm and Threadworm Infections and Their Association With Hemoglobin and Eosinophil Concentrations in Residents of Salvador-Bahia, Brazil

“…Controversially, the S. stercoralis-infected groups were not significantly different from the control group, except the adult male group. The development of anemia in S. stercoralis-infected individuals is correlated with alcoholism, malnutrition, the breakdown of local immune responses, and/or alterations in intestinal barriers 24,39,52 . Our population is characterized by a high socioeconomic status with access to basic sanitation and a good nutritional status.…”

“…This parasite can persist in the host for decades, leading to the development of gastrointestinal, pulmonary or cutaneous symptoms. Disseminated infection causes severe clinical manifestations and is frequently observed in immunocompromised or malnourished individuals 5,28,48,52 .…”

“…The association between S. stercoralis infection and anemia is rare, except in cases of hyperinfection 28,34,39,43,52 . In contrast, hookworm infection induces iron deficiency, which constitutes one of the world's major nutritional problems 2,21,42,49 .…”

Strongyloides Stercoralis and Its Risk Factors: An Experience at a Tertiary Care Hospital

“…It is a known fact that the survival of Strongyloides stercoralis in chronic alcoholics is also due to the breakdown of immune responses in the gastrointestinal tract as a result of alteration in intestinal barriers and there is elevated cortisone, which suppresses the immunity further. (16) Also, alcohol stimulates the transformation of rhabditiform larvae to filariform larvae within the intestine, thereby leading to autoinfection. (17) Strongyloides stercoralis is atypical in the helminthic group undergoing auto-infection, where the parasite undergoes reproduction within human beings leading to infection lasting for ages.…”

Falla orgánica múltiple por estrongiloidiasis diseminada: Comunicación de un caso

“…En primer lugar los malos hábitos de higiene, como caminar descalzos, la autoinfección al evacuar en sus propias ropas o higiene deficiente después de la evacuación 14 . En segundo lugar, puede haber compromiso de la inmunidad de la mucosa intestinal, así como la inmunidad celular, humoral o el sistema del complemento 14,15 . Recientemente se ha reportado una relación directa entre la gravedad del alcoholismo crónico y la infección por esta helmintiasis 16 .…”