Entamoeba infections and associated risk factors among migrant workers in Peninsular Malaysia.

The influx of low skilled migrant workers to Malaysia from low socio-economic countries where gastrointestinal parasitic infections are prevalent has raised concerns about transmission to the local population. Three methods for detection (serology, microscopy and molecular techniques) were utilized to identify Entamoeba infections amongst the targeted cohort and determine risk factors associated with infection. Serological screening of 484 migrant workers from five working sectors in Peninsular Malaysia using IgG4 ELISA based on the rPPDK antigen showed an overall seroprevalence of 7.4% (n = 36; CL95 = 5.3-10.1%) with only one factor statistically associated with seropositivity of anti-amoebic antibodies, i.e. years of residence in Malaysia (χ2 1 = 4.007, p = 0.045). Microscopic examination of 388 faecal samples for protozoan cysts and trophozoites showed a slightly higher prevalence (11.6%; n=45; CL95: 8.4-14.8%). Meanwhile, amplification of the 16S rDNA gene detected two species i.e. Entamoeba dispar (23/388; 5.9%; CL95: 3.6-8.3%) and E. histolytica (11/388; 2.8%; CL95: 1.2-4.5%) and mixed infections with both parasites in only three samples (3/388; 0.8%; CL95: 0.2-2.2%). Entamoeba dispar infection was significantly associated with those employed in food and domestic services (χ2 4 = 12.879, p = 0.012). However, none of the factors affected the prevalence of E. histolytica infection. Despite the low prevalence of E. histolytica in faecal samples of the study cohort, the presence of this pathogenic parasite still poses potential public health risks and calls for tighter control strategies based on better availability of chemotherapeutic treatment and accessibility to appropriate health education.

Entamoeba infections and associated risk factors among migrant workers in Peninsular Malaysia

@#The influx of low skilled migrant workers to Malaysia from low socio-economic countries where gastrointestinal parasitic infections are prevalent has raised concerns about transmission to the local population. Three methods for detection (serology, microscopy and molecular techniques) were utilized to identify Entamoeba infections amongst the targeted cohort and determine risk factors associated with infection. Serological screening of 484 migrant workers from five working sectors in Peninsular Malaysia using IgG4 ELISA based on the rPPDK antigen showed an overall seroprevalence of 7.4% (n = 36; CL95 = 5.3–10.1%) with only one factor statistically associated with seropositivity of anti-amoebic antibodies, i.e. years of residence in Malaysia (χ2 1 = 4.007, p = 0.045). Microscopic examination of 388 faecal samples for protozoan cysts and trophozoites showed a slightly higher prevalence (11.6%; n=45; CL95: 8.4–14.8%). Meanwhile, amplification of the 16S rDNA gene detected two species i.e. Entamoeba dispar (23/388; 5.9%; CL95: 3.6–8.3%) and E. histolytica (11/388; 2.8%; CL95: 1.2–4.5%) and mixed infections with both parasites in only three samples (3/388; 0.8%; CL95: 0.2–2.2%). Entamoeba dispar infection was significantly associated with those employed in food and domestic services (χ2 4 = 12.879, p = 0.012). However, none of the factors affected the prevalence of E. histolytica infection. Despite the low prevalence of E. histolytica in faecal samples of the study cohort, the presence of this pathogenic parasite still poses potential public health risks and calls for tighter control strategies based on better availability of chemotherapeutic treatment and accessibility to appropriate health education.

Epidemiology and immunodiagnostics of Strongyloides stercoralis infections among migrant workers in Malaysia

To investigate the status of Strongyloides(S.) stercoralis infections among migrant workers in Malaysia for the first time and identify risk factors. Methods: Four diagnostic methods were employed for the detection of S. stercoralis including microscopy, enzyme-linked immunosorbent assay (ELISA) using a commercial kit, ELISA using the rSs1a antigen and polymerase chain reaction (PCR). Low and semi-skilled workers from five working sectors (i.e. manufacturing, food service, agriculture and plantation, construction and domestic service) were tested on a voluntary basis. Results: The overall seroprevalence of S. stercoralis from 483 workers employing the ELISA commercial kit for IgG was 35.8% (n=173; 95% CI: 31.5%-40.1%) whereas seroprevalence using the rSs1a-ELISA was 13.0% (n=63; 95% CI: 10.0%-16.0%). Cross tabulation between the ELISA commercial kit and rSs1a-ELISA showed that only 6.4% (n=31; 95% CI: 4.2%-8.6%) of the samples were positive in both tests. Microscopic examination of all 388 fecal samples were negative; however subsequent testing by a nested PCR against DNA from the same samples successfully amplified DNA from three male subjects (0.8%; 3/388). Male workers, India and Myanmar nationality, food service occupation and those living in the hostel were statistically significant with seroprevalence (P<0.005). Conclusion: This is the first report on the epidemiology of S. stercoralis infections among the migrant workers in Malaysia. Our results highlight the importance of using appropriate diagnostic tools for detection. The presence of anti-S. stercoralis antibodies in the study population calls for improvements in personal hygiene and sanitation standards among migrant workers in Malaysia through control strategies including health education campaigns and programs aimed at increasing awareness and healthy behaviors.

Distribution of Giardia duodenalis (Assemblages A and B) and Cryptosporidium parvum amongst migrant workers in Peninsular Malaysia.

The influx of low skilled workers from socioeconomically deprived neighbouring countries to Malaysia has raised concerns about the transmission of communicable gastrointestinal diseases such as giardiasis and cryptosporidiosis to the local population. Therefore, a cross sectional study was conducted to investigate the prevalence of both diseases and the genetic diversity of these pathogens in the migrant population. Microscopic examination of faecal samples from 388 migrant workers involved in five working sectors were screened and 10.8% (n = 42) were found to be positive with Giardia spp. and 3.1% (n = 12) with Cryptosporidium spp. infections. PCR amplicons at the triosephosphate isomerase (tpi) gene were successfully obtained for Giardia duodenalis from 30 (30/388; 7.73%) samples with assemblages AII and B in 13 (13/30; 43.3%) and 17 (17/30; 56.7%) positive samples, respectively. Nine samples (9/388; 2.3%) were identified as Cryptosporidium parvum using PCR-RFLP analysis. Country of origin, duration of residence in Malaysia and working sectors significantly influenced G. duodenalis assemblage AII infections amongst the targeted population. Meanwhile, C. parvum infection was significantly associated with those working in the food service sector. Despite the low presence of pathogenic G. duodenalis and C. parvum in the study population, the results highlight the risk of anthroponotic foodborne and waterborne transmission and therefore call for implementation of control strategies through improvements in personal hygiene and sanitation standards.

Sirolimus therapy in a child with partially diazoxide-responsive hyperinsulinaemic hypoglycaemia.

Hyperinsulinaemic hypoglycaemia (HH), which causes persistent neonatal hypoglycaemia, can result in neurological damage and it's management is challenging. Diazoxide is the first-line treatment, albeit not all patients will fully respond to it, as episodes of hypoglycaemia may persist and it entails unpleasant adverse effects. Sirolimus, an mTOR inhibitor, has reportedly been successful in treating children with severe diffuse HH, thus obviating the need for pancreatectomy. We report a girl with HH, with a novel heterozygous ABCC8 gene missense mutation (c.4154A>T/ p.Lys1385Thr), who was initially responsive to diazoxide therapy. After 11 months of diazoxide treatment, she developed intermittent, unpredictable breakthrough episodes of hypoglycaemia, in addition to generalized hypertrichosis and weight gain from enforced feeding to avoid hypoglycaemia. Sirolimus, which was commenced at 15 months of age, gradually replaced diazoxide, with significant reduction and abolition of hypoglycaemia. The hypertrichosis resolved and there was less weight gain given the reduced need for enforced feeding. Sirolimus, which was administered over the next 15 months, was well tolerated with no significant side effects and was gradually weaned off. After stopping sirolimus, apart from hypoglycaemia developing during an episode of severe viral gastroenteritis, the capillary glucose concentrations were maintained >3.5 mmol/L, even after a 10 h fast. Sirolimus may have a role in the treatment of partially diazoxide-responsive forms of HH who experience breakthrough hypoglycaemia, but the long-term safety and efficacy of sirolimus are not established. LEARNING POINTS: Conventional treatment of diffuse HH with diazoxide is not always effective in controlling hypoglycaemia and can be associated with unpleasant side effects.Sirolimus was successfully used to abolish recurrent hypoglycaemia in partially diazoxide-responsive HH, with resolution of unacceptable diazoxide-associated side effects.Sirolimus was well tolerated with no clinically significant side effects.Shortly after stopping sirolimus, the capillary glucose levels remained normoglycemic.

Molecular epidemiology of Cryptosporidium in HIV/AIDS patients in Malaysia.

Cryptosporidiosis is a particular concern in immunocompromised individuals where symptoms may be severe. The aim of this study was to examine the epidemiological and molecular characteristics of Cryptosporidium infections in HIV/AIDS patients in Malaysia in order to identify risk factors and facilitate control measures. A modified Ziehl-Neelsen acid fast staining method was used to test for the presence of Cryptosporidium oocysts in the stools of 346 HIV/AIDS patients in Malaysia. Standard coproscopical methods were used to identify infections with other protozoan or helminths parasites. To identify the species of Cryptosporidium, DNA was extracted and nested-PCR was used to amplify a portion of the SSU rRNA gene. A total of 43 (12.4%) HIV-infected patients were found to be infected with Cryptosporidium spp. Of the 43 Cryptosporidium-positive HIV patients, 10 (23.3%) also harboured other protozoa, and 15 (34.9%) had both protozoa and helminths. The highest rates of cryptosporidiosis were found in adult males of Malay background, intravenous drug users, and those with low CD4 T cell counts (i.e., < 200 cells/mm3). Most were asymptomatic and had concurrent opportunistic infections mainly with Mycobacterium tuberculosis. DNA sequence analysis of 32 Cryptosporidium isolates identified C. parvum (84.3%), C. hominis (6.3%), C. meleagridis (6.3%), and C. felis (3.1%). The results of the present study revealed a high prevalence of Cryptosporidium infection in hospitalized HIV/AIDS patients. The results also confirmed the potential significance of zoonotic transmission of C. parvum in HIV infected patients, as it was the predominant species found in this study. However, these patients were found to be susceptible to a wide range of Cryptosporidium species. Epidemiological and molecular characterization of Cryptosporidium isolates provides clinicians and researchers with further information regarding the origin of the infection, and may enhance treatment and control strategies.

Gastrointestinal parasites in rural dogs and cats in Selangor and Pahang states in Peninsular Malaysia.

To estimate the current prevalence of gastrointestinal (GI) parasites in dogs and cats, a total of 105 fresh faecal samples were collected from rural areas in Peninsular Malaysia. Each faecal sample was examined for the presence of GI parasites by microscopic examination after formalin-ether concentration technique and for protozoa, trichrome and Ziehl-Neelsen staining were employed. The overall prevalence of GI parasitic infection was 88.6% (95% CI = 82.5-94.7) in which 88.3% of dogs and 89.3% of cats were infected with at least one parasites species, respectively. There were 14 different GI parasites species (nematodes, cestodes and protozoa) detected, including Ancylostoma spp. (62.9%), Toxocara spp. (32.4%), Trichuris vulpis (21.0%), Spirometra spp. (9.5%), Toxascaris leonina (5.7%), Dipylidium caninum (4.8%), Ascaris spp. (2.9%), Hymenolepis diminuta (1.0%) and others. General prevalence of GI parasites showed a significant difference between helminth (84.4%) and protozoa (34.3%) infections. Monoparasitism (38.1%) was less frequent than polyparasitism (46.7%). As several of these GI parasites are recognized as zoonotic agents, the results of this investigation revealed that local populations may be exposed to a broad spectrum of zoonotic agents by means of environmental contamination with dogs and cats faeces and this information should be used to mitigate public health risks. Prevention and control measures have to be taken in order to reduce the prevalence rates especially in socioeconomically disadvantaged communities where animals live in close proximity to people, poor levels of hygiene and overcrowding together with a lack in veterinary attention and zoonotic awareness.

Differentiating Entamoeba histolytica, Entamoeba dispar and Entamoeba moshkovskii using nested polymerase chain reaction (PCR) in rural communities in Malaysia.

BACKGROUND: In this study, a total of 426 human faecal samples were examined for the presence of Entamoeba histolytica, Entamoeba dispar, Entamoeba moshkovskii infection via a combination of microscopic examination and nested polymerase chain reaction (PCR) targeting 16S ribosomal RNA of Entamoeba species. METHODS: Faecal sample were collected from 426 participants in five rural villages in Peninsular Malaysia. The faecal samples were processed by direct wet smear and formalin ethyl acetate concentration technique followed by iodine staining and examined via microscopy for the presence of Entamoeba species and other intestinal parasites. Microscopically positive samples for Entamoeba species cysts were further characterized using a Nested Polymerase Chain Reaction (Nested-PCR) targeting 16S-like ribosomal RNA gene. The data entry and analysis was carried out using the SPSS software (Statistical Package for the Social Sciences) program for Windows version 17 (SPSS, Chicago, IL, USA). RESULTS: Based on single faecal examination, overall prevalence of Entamoeba infection was 17.6% (75/426). Females (19.1%) were more commonly infected compared to males (15.9%). Comparison by age groups showed that adults (23.9%) had higher infection rates than children (15.3%). The PCR results showed that 52 out of 75 microscopy positive samples successfully generated species-specific amplicons. The infection with E. histolytica (75.0%; 39/52) was the most common, followed by E. dispar (30.8%; 18/52) and E. moshkovskii (5.8%; 3/52). Of these, 33 (63.5%) were shown to contain only E. histolytica, 10 (19.2%) contained E. dispar and 3 (5.8%) contained only E. moshkovskii. Mixed infection with E. histolytica and E. dispar was found in 6 (11.5%) samples. CONCLUSIONS: The present study essentially emphasized the benefit of molecular techniques in discriminating the pathogenic Entamoeba species from the non-pathogenic for accurate diagnosis and better management of amoebiasis. The presence of E. moshkovskii is of great public health concern as it was the first time it has been reported in Malaysia.

AIDS-defining illnesses: a comparison between before and after commencement of highly active antiretroviral therapy (HAART).

Attempts to address the significant impact of HAART on medical variables on the Malaysian HIV/AIDS population have yet to be evaluated. This study aims to analyze the proportions of AIDS-defining illnesses (ADIs) before and after HAART. A retrospective study was carried out on 128 new cases of HIV infected patients who first commenced HAART in 2004 at the national HIV reference center. Before commencement of HAART, 76 clinical episodes of ADIs were recorded in 52 patients. Most common being pulmonary Mycobacterium tuberculosis (28.9%), PCP (27.6%) and disseminated and extrapulmonary Mycobacterium tuberculosis (11.8%). During HAART, 8 clinical episodes of ADIs were documented in 7 patients with a median time of onset of 10 weeks after initiation of HAART (range, 4-36 weeks). The median CD4 count at the time of the commencement of HAART for these patients was 11 cells/mm(3). ADIs reported include PCP (2 episodes), disseminated and extrapulmonary Mycobacterium tuberculosis (2 episodes), extrapulmonary cryptococcosis (1 episode), esophageal candidiasis (1 episode), recurrent pneumonia (1 episode) and disseminated or extrapulmonary histoplasmosis (1 episode). Three (37.5%) of these occurred despite a reduction of viral load by at least 2 log(10) and an increased in the CD4 cell count. In conclusion, ADIs can still present after the initiation of successful HAART especially in those with CD4 counts below 100 cells/mm(3). In Malaysia, ADIs are the major causes of HIV/AIDS associated morbidity and mortality, thus increased awareness on the management of these illnesses is warranted especially in the months following HAART.