Strongyloides stercoralis hyper-infection syndrome in HIV+/AIDS patients in Iran

Abstract

Strongyloides stercoralis is an intestinal nematode in humans, distributed through tropical and subtropical regions of the world. In most individuals, the infection has a chronic nature due to auto-infection at the low level. Accelerated auto-infection, mainly after an alteration in immune status, can cause a syndrome of severe hyper-infection or potentially fatal disseminated strongyloidiasis. Due to the increasing numbers of immunocompromised patients in Iran, strongyloidiasis is an emerging public health concern in the country. In the current study, which was carried out between 2003 and 2005, for the investigation on strongyloidiasis in HIV(+)/AIDS patients, a total of 781 patients were examined by agar plate culture, formalin ether concentration, and direct smear preparation of stool samples. According to the results, 2 out of 781 HIV( + )/AIDS patients were found infected with S. stercoralis, but both patients were at the progressive stage of AIDS and showing severe hyper-infection syndrome. In both cases, numerous rhabditiform and filariform larvae were found in fresh stool direct smears, and rapid and intensive development of parasite in agar plate cultures. In conclusion, in the progressive stages of AIDS, as a result of immunosuppression conditions or in the context of chemotherapy, S. stercoralis is capable of inducing overwhelming infection.

Prevalence of Strongyloides stercoralis and other intestinal parasitic infections among mentally retarded residents in central institution of southern Iran

“…Our country is endemic for S. stercoralis, especially the north of Iran with temperate [17] and the south with warm and humid climate. Our studied people included severely mentally retarded individuals with unusual behaviors such as geophagia and coprophagia and strongyloidiasis was found to be high among them as we expected.…”

“…Moreover, asymptomatic infection can remain for decades due to the occurrence of several auto infection cycles [15,17] .…”

“…S. stercoralis's unique life cycle makes it possible to survive in human host and causes autoinfection to lead chronic disease which could have remained for several years [13][14][15] . Although most of infections are asymptomatic, disseminated and hyper infection may occur in immunocompromised and immune deficient individuals as a fatal disease [16][17][18][19][20] .…”

“…Few epidemiological studies carried out in mentally retarded populations in Iran [24,25] and other parts of the world have indicated the prevalence of intestinal parasitic infections among them [26][27][28][29] . The 17.3% showed the highest incidence followed by Entamoeba coli (9.8%), Blastocystis hominis (7.5%), Giardia lamblia (2.3%), Endolimax nana (2.3%), Hymenolepis nana (0.8%), Oxyuris vermicularis (0.8%), and Chilomasix mesnili (0.8%). Double infections were found to be as: Strongyloides stercoralis + Giardia lamblia (2.3%), Entamoeba coli + Giardia lamblia (1.5%), Entamoeba coli + Blastocystis hominis (1.5%), Oxyuris vermicularis + Entamoeba coli (0.8%), Strongyloides stercoralis + Entamoeba coli (0.8%), respectively.…”

A PCR-Based Molecular Detection of Strongyloides stercoralis in Human Stool Samples from Tabriz City, Iran

“…Autoinfection occurs frequently, leading to chronic disease remaining for several years [3,9,10]. Hyper and disseminated infections may occur in immunocompromised patients which could result in death [11,12,13,14,15]. …”