Prevalence of Dientamoeba fragilis, Giardia duodenalis, Entamoeba histolytica/dispar, and Cryptosporidium spp in Da Nang, Vietnam, detected by a multiplex real‐time PCR

Abstract

€Ogren J, Van Nguyen S, Nguyen MK, Dimberg J, Matussek A. Prevalence of Dientamoeba fragilis, Giardia duodenalis, Entamoeba histolytica/dispar and Cryptosporidium spp in Da Nang, Vietnam, detected by a multiplex real-time PCR. APMIS. 2016; 124: 529-533. We surveyed the prevalence of Dientamoeba fragilis, Giardia duodenalis, Entamoeba histolytica, Entamoeba dispar, and Cryptosporidium spp in individuals with and without gastrointestinal (GI) symptoms residing in and around Da Nang city, Vietnam. Fecal samples were collected from children (n = 100) and adults (n = 80) with GI symptoms and from healthy individuals (n = 88) reporting no GI symptoms. Parasite detection was performed by multiplex real-time PCR. Overall, except for G. duodenalis, we found a low prevalence (<5%) of D. fragilis and E. dispar and no detection of E. histolytica and C. spp in all participants with GI symptoms. Specifically for D. fragilis this contrasts with findings in European populations of children with GI symptoms showing prevalence up to 73%. Moreover, our results indicate that the prevalence of G. duodenalis is higher in patients with GI symptoms compared to asymptomatic individuals and this difference is most obvious in young patients.Key words: Dientamoeba fragilis; Giardia duodenalis; Entamoeba histolytica/dispar and Cryptosporidium spp; PCR; prevalence.Andreas Matussek, Division of Medical Diagnostics, Clinical Microbiology Laboratory, County Hospital Ryhov, 55185 J€ onk€ oping, Sweden. e-mail: andreas.matussek@rjl.seThe World Health Organization (WHO) ranks diarrheal disease as the second most common cause of morbidity and mortality in children in the developing world (1). Many studies have been conducted in various geographic areas to identify the etiology of these diarrheal illnesses and to formulate a composite picture for estimating their global burden. The etiological agents of diarrhea include viruses, bacteria, and parasites. Among parasites, Entamoeba histolytica, Giardia duodenalis, Cryptosporidium spp., and Dientamoeba fragilis are considered to be the most common (2-4).Dientamoeba fragilis is a flagellate that varies in prevalence from 1% to 70% depending on mode of detection and population studied (5, 6).Transmission of D. fragilis is not fully understood. It is thought to be transmitted via the ova of Enterobius vermicularis (7, 8) and also a cyst form has recently been detected that may play a role in the transmission (9). Its pathogenicity has been debated and studies have shown a correlation between infection and gastrointestinal (GI) symptoms in Swedish children (10).Giardia duodenalis is a flagellate common in most parts of the world and is considered as the most common non-viral cause of diarrhea. Infections can cause acute diarrhea with or without vomiting and fever, chronic infections causing malnutrition, lactose intolerance and abdominal pain, or asymptomatic infections (11).Entamoeba histolytica is the cause of amoebic colitis, amoebic dysentery, and amoebic liver Received 8 December 2015. Accepted 23 ...

Dientamoeba fragilis diagnosis by fecal screening: relative effectiveness of traditional techniques and molecular methods

“…Data on the international prevalence of D. fragilis are limited. Worldwide, the prevalence has been reported to range from 0.4% to 71% [2,8,11,12], making it a more frequent cause of gastrointestinal infection than Giardia lamblia [13][14][15]. The sensitivity of diagnostic techniques and the expertise of testing laboratories affect the reported prevalence rate of D. fragilis [14,16].…”

Genetic diversity in the metronidazole metabolism genes nitroreductases and pyruvate ferredoxin oxidoreductases in susceptible and refractory clinical samples of Giardia lamblia

“…Giardia cysts with beads from previous IMS steps, were frozen and thawed three times before adding proteinase K followed by AL buffer and RNase A from the MagAttract® kit. The samples were then incubated at 56 °C for 1 h according to ( Ogren et al, 2016 ), followed by 2 freeze-thaw cycles before a final heat incubation at 98 °C for 15 min. Remaining beads and cyst wall debris were pelleted and removed by centrifugation at 11000xG for 2 min before following the manufacturer's instructions.…”

Prevalence and genetic characterization of Dientamoeba fragilis in asymptomatic children attending daycare centers

“…Most studies on Dientamoeba prevalence come from high-income countries, however prevalence data have also been reported in developing regions where adequate sanitation is not available 2 – 4 . Recently, surveys based on microscopy and/or molecular assays have been carried out in low-resource communities in Asia 10 , Middle East 11 and Africa 12 . In Latin America, information is still limited 13 – 16 , including in Brazil, where there have been only four studies on this subject 17 – 20 .…”